Breast cancer is the second leading cause of cancer death among women and represents 14% of death in women around the world. The standard diagnosis method for breast tumor is mammography, which is often related with false-negative results leading to therapeutic delays and contributing indirectly to the development of metastasis. Therefore, the development of new tools that can detect breast cancer is an urgent need to reduce mortality in women. Here, we have developed Gd2O3:Eu3+ nanoparticles functionalized with folic acid (FA), for breast cancer detection. Gd2O3:Eu3+ nanoparticles were synthesized by sucrose assisted combustion synthesis and functionalized with FA using EDC-NHS coupling. The FA-conjugated Gd2O3:Eu3+ nanoparticles exhibit strong red emission at 613 nm with a quantum yield of ~ 35%. In vitro cytotoxicity studies demonstrated that the nanoparticles had a negligible cytotoxic effect on normal 293T and T-47D breast cancer cells. Cellular uptake analysis showed significantly higher internalization of FA-conjugated RE nanoparticles into T-47D cells (Folr hi ) compared to MDA-MB-231 breast cancer cells (Folr lo ). In vivo confocal and CT imaging studies indicated that FA-conjugated Gd2O3:Eu3+ nanoparticles accumulated more efficiently in T-47D tumor xenograft compared to the MDA-MB-231 tumor. Moreover, we found that FA-conjugated Gd2O3:Eu3+ nanoparticles were well tolerated at high doses (300 mg/kg) in CD1 mice after an intravenous injection. Thus, FA-conjugated Gd2O3:Eu3+ nanoparticles have great potential to detect breast cancer. Our findings provide significant evidence that could permit the future clinical application of FA-conjugated Gd2O3:Eu3+ nanoparticles alone or in combination with the current detection methods to increase its sensitivity and precision.

In topographically complex terrains, downslope movement of soil organic carbon (OC) can influence local carbon balance. The primary purpose of the present analysis is to compare the magnitude of OC displacement by erosion with ecosystem metabolism in such a complex terrain. Does erosion matter in this ecosystem carbon balance? We have used the Revised Universal Soil Loss Equation (RUSLE) erosion model to estimate lateral fluxes of OC in a watershed in northwestern Mexico. The watershed (4900 km²) has an average slope of 10° ± 9° (mean ± SD); 45% is >10°, and 3% is >30°. Land cover is primarily shrublands (69%) and agricultural lands (22%). Estimated bulk soil erosion averages 1350 Mg·km⁻²·yr⁻¹. We estimate that there is insignificant erosion on slopes <2° and that 20% of the area can be considered depositional. Estimated OC erosion rates are 10 Mg·km⁻²·yr⁻¹ for areas steeper than 2°. Over the entire area, erosion is ∼50% higher on shrublands than on agricultural lands, but within slope classes, erosion rates are more rapid on agricultural areas. For the whole system, estimated OC erosion is ∼2% of net primary production (NPP), increasing in high‐slope areas to ∼3% of NPP. Deposition of eroded OC in low‐slope areas is ∼10% of low‐slope NPP. Soil OC movement from erosional slopes to alluvial fans alters the mosaic of OC metabolism and storage across the landscape.

In this work, we report new chemical and isotopic data (³He/⁴He, δ¹³C_CO2, δ¹³C_CH4, and δD_CH4) from poorly or previously unstudied hydrothermal and magmatic gases that are emitted along the eastern coast of the Baja California Peninsula (BCP). High ³He/⁴He values (up to ~7 Ra) characterize the magmatic gases, while lower ratios (≤1.6 Ra) characterize hydrothermal springs. We infer that the mantle beneath the BCP could be Mid‐ocean‐ridge basalt (MORB)‐likes, as in the rift within the Gulf of California, or it may reflect contamination from C‐rich sediment during paleo‐subduction of the Farallon plate. During their ascent, through the crust, mantle/magmatic gases mix with CO₂‐ and ⁴He‐rich fluids, thus forming CO₂‐rich hydrothermal gases. These hydrothermal gases undergo partial dissolution of CO₂ in shallow waters under different temperature and pH conditions, which further modifies their composition. Thermogenic and possibly abiogenic sources of methane are present only in magmatic gases from the BCP. Secondary methane oxidation (microbial/inorganic) processes are proposed for some hydrothermal gases, which are extremely enriched in heavy isotopes. Finally, we argue that the hydrothermal gases that are emitted from the BCP have variable percentages of mantle contribution, indicating the presence of lithospheric faults enhancing the rise of mantle fluids also in areas where volcanism is absent.

The soil and water assessment tool (SWAT) model was applied for the first time in Cuba to assess the potential impacts of climate change on water availability in the Cauto River basin. The model was calibrated (and validated) for the 2001–2006 (2007–2010) period at a monthly timescale in two subbasins La Fuente and Las Coloradas, representative of middle and upper sections of the Cauto basin; the calibrated models showed good performance. The output available for the regional climate Model RegCM4.3 was used to force the calibrated SWAT models to simulate a baseline (1970–2000) period and near-future (2015–2039) hydrologic regimes under the representative concentration pathway (RCP) 8.5 emission scenario. The future projections suggest regional increases of 1.5 °C in mean annual temperature and a 38% decrease in mean annual precipitation in the subbasins. These changes translate to possible reductions in the annual streamflow of up to 61% with respect to the baseline period, whereas the aquifer recharge in the basin is expected to decrease up to 58%, with a consequent reduction of groundwater flow, especially during the boreal summer wet season. These projection scenarios should be of interest to water resources managers in tropical regions.

This paper used Landsat-5 Thematic Mapper (TM) data from 2007 to 2011 to examine seasonal changes in the normalized difference vegetation index (NDVI) in north-facing and south-facing slopes of a small (approximately 1900 ha.) west-draining hydrographic basin in the Guadalupe Valley in northwest Mexico. The analysis was done for the wet and dry seasons of this mid-latitude (32°N) basin with a rugged geomorphology covered by mostly native vegetation (chaparral) with minor anthropogenic disturbance. We used ten Landsat-5 TM satellite images that were preprocessed to correct atmospheric effects, to further estimate radiance and reflectance before the NDVI computation was performed. A LiDAR derived digital terrain model was used to calculate the terrain slope and aspect to further select and classify north and south facing slopes. With the slopes classified, zonal statistics of the NDVI were computed estimating mean and standard deviation for both slope orientations. We found higher NDVI values in the north-facing than in the south-facing slopes, regardless of the season (wet and dry), and also higher vegetation index values during the wet season compared to the dry season. For the period analyzed, we distinguished the signal of extreme dry year during 2007.