Identification and impact of excess soil potassium on crop and livestock nutrition

Several soils have been identified in the Intermountain West which contain excessive amounts of extractable potassium (K). A "normal" ammonium acetate extractable potassium level may be from 200 to 500 parts per million (ppm), while the high potassium soils contain 1,000 to over 7,000 ppm. Initial observation of crops grown on these soils continually showed poor crop yield, general chlorosis and failure to respond to fertilizer additions. While not widely reported in the literature, these soils have been identified at sites in Idaho, Montana, Oregon, Utah and Wyoming. Their discovery suggests a need to further explore the distribution and origin of high extractable K soils. We may also be able to define steps to improve crop and livestock productivity on the sites. This paper presents what we know about excess-K soils and outlines current efforts to determine their origin, chemistry and impacts on crops and livestock

Interwell coupling effect in Si/SiGe quantum wells grown by ultra high vacuum chemical vapor deposition

Si/Si0.66Ge0.34coupled quantum well (CQW) structures with different barrier thickness of 40, 4 and 2 nm were grown on Si substrates using an ultra high vacuum chemical vapor deposition (UHV-CVD) system. The samples were characterized using high resolution x-ray diffraction (HRXRD), cross-sectional transmission electron microscopy (XTEM) and photoluminescence (PL) spectroscopy. Blue shift in PL peak energy due to interwell coupling was observed in the CQWs following increase in the Si barrier thickness. The Si/SiGe heterostructure growth process and theoretical band structure model was validated by comparing the energy of the no-phonon peak calculated by the 6 + 2-bandk·pmethod with experimental PL data. Close agreement between theoretical calculations and experimental data was obtained

Genetic Sharing with Cardiovascular Disease Risk Factors and Diabetes Reveals Novel Bone Mineral Density Loci.

Bone Mineral Density (BMD) is a highly heritable trait, but genome-wide association studies have identified few genetic risk factors. Epidemiological studies suggest associations between BMD and several traits and diseases, but the nature of the suggestive comorbidity is still unknown. We used a novel genetic pleiotropy-informed conditional False Discovery Rate (FDR) method to identify single nucleotide polymorphisms (SNPs) associated with BMD by leveraging cardiovascular disease (CVD) associated disorders and metabolic traits. By conditioning on SNPs associated with the CVD-related phenotypes, type 1 diabetes, type 2 diabetes, systolic blood pressure, diastolic blood pressure, high density lipoprotein, low density lipoprotein, triglycerides and waist hip ratio, we identified 65 novel independent BMD loci (26 with femoral neck BMD and 47 with lumbar spine BMD) at conditional FDR < 0.01. Many of the loci were confirmed in genetic expression studies. Genes validated at the mRNA levels were characteristic for the osteoblast/osteocyte lineage, Wnt signaling pathway and bone metabolism. The results provide new insight into genetic mechanisms of variability in BMD, and a better understanding of the genetic underpinnings of clinical comorbidity

Identification and impact of excess soil potassium on crop and livestock nutrition

Several soils have been identified in the Intermountain West which contain excessive amounts of extractable potassium (K). A "normal" ammonium acetate extractable potassium level may be from 200 to 500 parts per million (ppm), while the high potassium soils contain 1,000 to over 7,000 ppm. Initial observation of crops grown on these soils continually showed poor crop yield, general chlorosis and failure to respond to fertilizer additions. While not widely reported in the literature, these soils have been identified at sites in Idaho, Montana, Oregon, Utah and Wyoming. Their discovery suggests a need to further explore the distribution and origin of high extractable K soils. We may also be able to define steps to improve crop and livestock productivity on the sites. This paper presents what we know about excess-K soils and outlines current efforts to determine their origin, chemistry and impacts on crops and livestock