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Climate adaptation by crop migration.
Many studies have estimated the adverse effects of climate change on crop yields, however, this literature almost universally assumes a constant geographic distribution of crops in the future. Movement of growing areas to limit exposure to adverse climate conditions has been discussed as a theoretical adaptive response but has not previously been quantified or demonstrated at a global scale. Here, we assess how changes in rainfed crop area have already mediated growing season temperature trends for rainfed maize, wheat, rice, and soybean using spatially-explicit climate and crop area data from 1973 to 2012. Our results suggest that the most damaging impacts of warming on rainfed maize, wheat, and rice have been substantially moderated by the migration of these crops over time and the expansion of irrigation. However, continued migration may incur substantial environmental costs and will depend on socio-economic and political factors in addition to land suitability and climate
Determination of the critical current density in the d-wave superconductor YBCO under applied magnetic fields by nodal tunneling
We have studied nodal tunneling into YBa2Cu3O7-x (YBCO) films under magnetic
fields. The films' orientation was such that the CuO2 planes were perpendicular
to the surface with the a and b axis at 450 form the normal. The magnetic field
was applied parallel to the surface and perpendicular to the CuO2 planes. The
Zero Bias Conductance Peak (ZBCP) characteristic of nodal tunneling splits
under the effect of surface currents produced by the applied fields. Measuring
this splitting under different field conditions, zero field cooled and field
cooled, reveals that these currents have different origins. By comparing the
field cooled ZBCP splitting to that taken in decreasing fields we deduce a
value of the Bean critical current superfluid velocity, and calculate a Bean
critical current density of up to 3*10^7 A/cm2 at low temperatures. This
tunneling method for the determination of critical currents under magnetic
fields has serious advantages over the conventional one, as it avoids having to
make high current contacts to the sample.Comment: 8 pages, 2 figure
Factorial Design Experiment to Analyze the Response of a Luminescent Photoelastic Coating
Observations of Pauli Paramagnetic Effects on the Flux Line Lattice in CeCoIn5
From small-angle neutron scattering studies of the flux line lattice (FLL) in
CeCoIn5, with magnetic field applied parallel to the crystal c-axis, we obtain
the field- and temperature-dependence of the FLL form factor, which is a
measure of the spatial variation of the field in the mixed state. We extend our
earlier work [A.D. Bianchi et al. 2008 Science 319, 177] to temperatures up to
1250 mK. Over the entire temperature range, paramagnetism in the flux line
cores results in an increase of the form factor with field. Near H_c2 the form
factor decreases again, and our results indicate that this fall-off extends
outside the proposed FFLO region. Instead, we attribute the decrease to a
paramagnetic suppression of Cooper pairing. At higher temperatures, a gradual
crossover towards more conventional mixed state behavior is observed.Comment: Submitted to New Journal of Physics, 13 pages, 4 figure
Endoscopic Evidence That Randall's Plaque is Associated with Surface Erosion of the Renal Papilla
OBJECTIVE:
This study was conducted to assess the reliability and precision of an endoscopic grading scale to identify renal papillary abnormalities across a spectrum of equipment, locations, graders, and patients.
MATERIALS AND METHODS:
Intra- and interobserver reliability of the papillary grading system was assessed using weighted kappa scoring among 4 graders reviewing a single renal papilla from 50 separate patients on 2 occasions. Grading was then applied to a cohort of patients undergoing endoscopic stone removal procedures at two centers. Patient factors were compared with papillary scores on the level of the papilla, kidney, and patient.
RESULTS:
Graders achieved substantial (kappa >0.6) intra- and inter-rater reliability in scored domains of ductal plugging, surface pitting, and loss of contour. Agreement for Randall's Plaque (RP) was moderate. Papillary scoring was then performed for 76 patients (89 kidneys, 533 papillae). A significant association was discovered between pitting and RP that held both within and across institutions. A general linear model was then created to further assess this association and it was found that RP score was a highly significant independent correlate of pitting score (Fâ=â7.1; pâ<â0.001). Mean pitting scores increased smoothly and progressively with increasing RP scores. Sums of the scored domains were then calculated as a reflection of gross papillary abnormality. When analyzed in this way, a history of stone recurrence and shockwave lithotripsy were strongly predictive of higher sums.
CONCLUSIONS:
Renal papillary pathology can be reliably assessed between different providers using a newly described endoscopic grading scale. Application of this scale to stone-forming patients suggests that the degree of RP appreciated in the papilla is strongly associated with the presence of pitting. It also suggests that patients with a history of recurrent stones and lithotripsy have greater burdens of gross papillary disease
Financing Direct Democracy: Revisiting the Research on Campaign Spending and Citizen Initiatives
The conventional view in the direct democracy literature is that spending against a measure is more effective than spending in favor of a measure, but the empirical results underlying this conclusion have been questioned by recent research. We argue that the conventional finding is driven by the endogenous nature of campaign spending: initiative proponents spend more when their ballot measure is likely to fail. We address this endogeneity by using an instrumental variables approach to analyze a comprehensive dataset of ballot propositions in California from 1976 to 2004. We find that both support and opposition spending on citizen initiatives have strong, statistically significant, and countervailing effects. We confirm this finding by looking at time series data from early polling on a subset of these measures. Both analyses show that spending in favor of citizen initiatives substantially increases their chances of passage, just as opposition spending decreases this likelihood
Four individually identified paired dopamine neurons signal reward in larval Drosophila
Dopaminergic neurons serve multiple functions, including reinforcement processing during associative learning [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12]. It is thus warranted to understand which dopaminergic neurons mediate which function. We study larval Drosophila, in which only approximately 120 of a total of 10,000 neurons are dopaminergic, as judged by the expression of tyrosine hydroxylase (TH), the rate- limiting enzyme of dopamine biosynthesis [ 5 and 13]. Dopaminergic neurons mediating reinforcement in insect olfactory learning target the mushroom bodies, a higher-order âcorticalâ brain region [ 1, 2, 3, 4, 5, 11, 12, 14 and 15]. We discover four previously undescribed paired neurons, the primary protocerebral anterior medial (pPAM) neurons. These neurons are TH positive and subdivide the medial lobe of the mushroom body into four distinct subunits. These pPAM neurons are acutely necessary for odor-sugar reward learning and require intact TH function in this process. However, they are dispensable for aversive learning and innate behavior toward the odors and sugars employed. Optogenetical activation of pPAM neurons is sufficient as a reward. Thus, the pPAM neurons convey a likely dopaminergic reward signal. In contrast, DL1 cluster neurons convey a corresponding punishment signal [5], suggesting a cellular division of labor to convey dopaminergic reward and punishment signals. On the level of individually identified neurons, this uncovers an organizational principle shared with adult Drosophila and mammals [ 1, 2, 3, 4, 7, 9 and 10] (but see [6]). The numerical simplicity and connectomic tractability of the larval nervous system [ 16, 17, 18 and 19] now offers a prospect for studying circuit principles of dopamine function at unprecedented resolution
Bioengineered small extracellular vesicles deliver multiple SARSâCoVâ2 antigenic fragments and drive a broad immunological response
The COVIDâ19 pandemic highlighted the clear risk that zoonotic viruses pose to global health and economies. The scientific community responded by developing several efficacious vaccines which were expedited by the global need for vaccines. The emergence of SARSâCoVâ2 breakthrough infections highlights the need for additional vaccine modalities to provide stronger, longâlived protective immunity. Here we report the design and preclinical testing of small extracellular vesicles (sEVs) as a multiâsubunit vaccine. Cell lines were engineered to produce sEVs containing either the SARSâCoVâ2 Spike receptorâbinding domain, or an antigenic region from SARSâCoVâ2 Nucleocapsid, or both in combination, and we tested their ability to evoke immune responses in vitro and in vivo. B cells incubated with bioengineered sEVs were potent activators of antigenâspecific T cell clones. Mice immunised with sEVs containing both sRBD and Nucleocapsid antigens generated sRBDâspecific IgGs, nucleocapsidâspecific IgGs, which neutralised SARSâCoVâ2 infection. sEVâbased vaccines allow multiple antigens to be delivered simultaneously resulting in potent, broad immunity, and provide a quick, cheap, and reliable method to test vaccine candidates
Pathways for recent Cerrado soybean expansion : extending the soy moratorium and implementing integrated crop livestock systems with soybeans.
The Brazilian Soy Moratorium has effectively reduced forest conversion for soybeans in Amazonia.
This has come at the expense of the region?s pasturelands, which have increasingly ceded space for
compliant soy expansion. The question of extending the policy to the Cerrado, where recent soy
expansion has come at the cost of ecologically valuable vegetation, plugs into a wider discussion on
how to reconcile competing commodities on finite amounts of cleared area. Innovative management
strategies that allow different land uses to coexist are urgently needed. Integrated crop-livestock
systems with soybeans(ICLS)rotates beef and soy on the same area, and shows promise as a means to
improve production, farmer benefit, and environmental impacts. Here we reconstruct historical land
use maps to estimate Cerrado Soy Moratorium outcomes with benchmark years in 2008 and 2014, we
then estimate additional production afforded by ICLS implementation between 2008 and 2014. We
find that if a 2008 Cerrado Soy Moratorium were in place, 0.7 Mha of 2014 Cerrado soy area would
currently be in violation of the policy. Roughly 96% of this acreage is found in Matopiba (82%) and
Mato Grosso (14%)states, suggesting that adoption may have slowed recent production in these
rapidly transforming soy centers, in contrast to central and southwestern Cerrado where there is more
concentrated eligible expansion area. Changing the benchmark to 2014 could have added 0.7 Mha of
eligible expansion area, though over 80% of these additions would be in states with the most 2008
eligible area (Distrito Federal, Mato Grosso, Maranh?o, Minas Gerais, Mato Grosso do Sul).
Meanwhile, ICLS adoption could have added between 4.0 and 32 Mha of new soy land to the study
area without additional clearing between 2008 and 2014, though this would depend on rigorous
accompanying land zoning policy to guide implementation. The roughly 5 Mha of Cerrado soybean
expansion that actually occurred between 2008 and 2014 could have been accommodated on 2008
suitable pasture area given an ICLS rotation frequency of every 6 years or less. Conservation estimates
presented here represent the upper limit of what is possible, as our scenario modeling does not account
for variables such as leakage, laundering, or rebound effects
Does direct democracy hurt immigrant minorities?: evidence from naturalization decisions in Switzerland
Do minorities fare worse under direct democracy than under representative democracy? We provide new evidence by studying naturalization requests of immigrants in Switzerland that were typically decided with referendums in each municipality. Using panel data from about 1,400 municipalities for the 1991â2009 period, we exploit Federal Court rulings that forced municipalities to transfer the decisions to their elected municipality councils. We find that naturalization rates surged by about 60% once politicians rather than citizens began deciding on naturalization applications. Whereas voters in referendums face no cost of arbitrarily rejecting qualified applicants based on discriminatory preferences, politicians in the council are constrained to formally justify rejections and may be held accountable by judicial review. Consistent with this mechanism, the increase in naturalization rates caused by switching from direct to representative democracy is much stronger for more marginalized immigrant groups and in areas where voters are more xenophobic or where judicial review is more salient
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