Monitoring spatiotemporal variation of groundwater level and salinity under land use change using integrated field measurements, GIS, geostatistical, and remote-sensing approach: case study of the Feija aquifer, Middle Draa watershed, Moroccan Sahara.

The cultivation of watermelons has been a fast growing agriculture industry in the arid, desert regions of Morocco, relying on groundwater pumping and transformation of rangelands to farms due to growing demand for the fruit in national and international markets. This study aims to measure the impact of watermelon expansion on groundwater resources in the Feija Basin, which is one of the largest watermelon cultivation areas in Southern Morocco. Field measurements, statistics, Kriging interpolation, and regression methods were used to measure the temporal variations in the groundwater level (GL) and salinity between 2013 and 2018 to determine the correlation between different parameters. Remote sensing data was also used to monitor the watermelon cultivation expansion. Results show a rapid expansion of agricultural areas from just 185.11 ha in 2007 to 2560.1 ha in 2018. The groundwater level declined rapidly by about 10 m below ground level during the 5 years of the study period. Additionally, the decline was accompanied by a significant increase in electrical conductivity (salinity) values over the same time interval from 1077.55 to 1211.9 µS/cm. As a consequence of the continuous overexploitation and unsustainable management, a lot of wells have run dry and there have been drinking water shortages in the city of Zagora, the closest city nearby. Results can help target efforts to improve the implementation of conservation strategies to ensure the sustainability of water use and food production in this region of Morocco.

Somatic Mosaicism of a PDGFRB Activating Variant in Aneurysms of the Intracranial, Coronary, Aortic, and Radial Artery Vascular Beds.

Background Activating variants in platelet-derived growth factor receptor beta (PDGFRB), including a variant we have previously described (p.Tyr562Cys [g.149505130T>C [GRCh37/hg19]; c.1685A>G]), are associated with development of multiorgan pathology, including aneurysm formation. To investigate the association between the allele fraction genotype and histopathologic phenotype, we performed an expanded evaluation of post-mortem normal and aneurysmal tissue specimens from the previously published index patient. Methods and Results Following death due to diffuse subarachnoid hemorrhage in a patient with mosaic expression of the above PDGFRB variant, specimens from the intracranial, coronary, radial and aortic arteries were harvested. DNA was extracted and alternate allele fractions (AAF) of PDGFRB were determined using digital droplet PCR. Radiographic and histopathologic findings, together with genotype expression of PDGFRB were then correlated in aneurysmal tissue and compared to non-aneurysmal tissue. The PDGFRB variant was identified in the vertebral artery, basilar artery, and P1 segment aneurysms (AAF: 28.7%, 16.4%, and 17.8%, respectively). It was also identified in the coronary and radial artery aneurysms (AAF: 22.3% and 20.6%, respectively). In phenotypically normal intracranial and coronary artery tissues, the PDGFRB variant was not present. The PDGFRB variant was absent from lymphocyte DNA and normal tissue, confirming it to be a non-germline somatic variant. Primary cell cultures from a radial artery aneurysm localized the PDGFRB variant to CD31-, non-endothelial cells. Conclusions Constitutive expression of PDGFRB within the arterial wall is associated with the development of human fusiform aneurysms. The role of targeted therapy with tyrosine kinase inhibitors in fusiform aneurysms with PDGFRB mutations should be further studied.

Racial, ethnic, and gender diversity of applicants and matriculants to neurological surgery residency programs.

OBJECTIVE: The aim of this study was to identify trends in the demographic constitution of applicants and matriculants to neurological surgery based on race, ethnicity, and gender. METHODS: The authors conducted a cross-sectional study using compiled demographic data obtained from the Association of American Medical Colleges. Trends analyzed included proportional changes in race, ethnicity, and gender of applicants and matriculants to neurosurgical residency programs from academic years 2010-2011 to 2018-2019. RESULTS: A total of 5100 applicants and 2104 matriculants to neurosurgical residency programs were analyzed. No significant change in the percentage of overall women applicants (+0.3%, 95% CI -0.7% to 1.3%; p = 0.77) or in the percentage of women matriculants (+0.3%, 95% CI -2.2% to 2.9%; p = 0.71) was observed. For applicants, no change over time was observed in the percentages of American Indian or Alaska Native (AI/AN) men (0.0%, 95% CI -0.3% to 0.3%; p = 0.65); Asian men (-0.1%, 95% CI -1.2% to 1.1%; p = 0.97); Black or African American men (-0.2%, 95% CI -0.7% to 0.4%; p = 0.91); Hispanic, Latino, or of Spanish Origin men (+0.4%, 95% CI -0.8% to 1.7%; p = 0.26); White men (+0.5%, 95% CI -2.1% to 3.0%; p = 0.27); Asian women (+0.1,% 95% CI -0.9% to 1.1%; p = 0.73); Black or African American women (0.0%, 95% CI -0.6% to 0.5%; p = 0.30); Hispanic, Latino, or of Spanish Origin women (0.0%, 95% CI -0.4% to 0.4%; p = 0.71); and White women (+0.3%, 95% CI -1.1% to 1.7%; p = 0.34). For matriculants, no change over time was observed in the percentages of AI/AN men (0.0%, 95% CI -0.6% to 0.6%; p = 0.56); Asian men (0.0%, 95% CI -2.7% to 2.7%; p = 0.45); Black or African American men (-0.3%, 95% CI -1.4% to 0.8%; p = 0.52); Hispanic, Latino, or of Spanish Origin men (+0.6%, 95% CI -0.8 to 2.0%; p = 0.12); White men (-1.0%, 95% CI -5.3% to 3.3%; p = 0.92); Asian women (+0.1%, 95% CI -1.3% to 1.5%; p = 0.85); Black or African American women (0.0%, 95% CI -0.6% to 0.7%; p = 0.38); Hispanic, Latino, or of Spanish Origin women (-0.1%, 95% CI -0.7% to 0.5%; p = 0.46); and White women (+0.3%, 95% CI -2.4% to 3.0%; p = 0.70). CONCLUSIONS: Despite efforts to diversify the demographic constitution of incoming neurosurgical trainees, few significant advances have been made in recent years. This study suggests that improved strategies for recruitment and cultivating early interest in neurological surgery are required to further increase the diversification of future cohorts of neurosurgical trainees.