Lessons from upstream soil conservation measures to mitigate soil erosion and its impact on upstream and downstream users of the Nile River

A study was conducted to evaluate the effects of soil bunds stabilized with vetiver grass (V. zizanioides) and tree lucerne (C. palmensis) on selected soil physical and chemical properties, bund height, inter-terrace slope and barley (Hordeum vulgare L.) yield in Absela site, Banja Shikudad District, Awi administrative Zone of the Amhara National Regional State (ANRS) located in the Blue Nile Basin. The experiment had five treatments that included non-conserved land (control), a 9-year old soil bund stabilized with tree lucerne, a 9-year old soil bund stabilized with vetiver grass, a 9-year old sole soil bund, and a 6-year old soil bund stabilized with tree lucerne. Data were analyzed using one-way analysis of variance (ANOVA) and mean values for the treatments were separated using the Duncan Multiple Range Test. Results of the experiment indicated that organic carbon (OC), total nitrogen (N), bulk density, infiltration rate, bund height, and inter-terrace slope are significantly (p?0.05) affected by soil conservation measures. The non-conserved fields had significantly lower OC, total N, and infiltration rate; whereas higher bulk density as compared to the conserved fields with different conservation measures. However, no significant differences in bulk density were observed among the conservation methods. The field treated with 9-year old soil bund stabilized with tree lucerne or sole soil bund had significantly higher OC content than all other treatments. Fields having 6-year old soil bunds had lower OC and total N when compared to fields having 9-year old soil bunds irrespective of their method of stabilization. Fields with soil bunds stabilized with vetiver grass had the highest bund height and the lowest inter-terrace slope than fields with the remaining conservation measures. Barley grain and straw yields were significantly (P<0.05) greater in both the soil accumulation and loss zones of the conserved fields than the non-conserved (control) ones. In the accumulation zone, fields with the 9-year old soil bund stabilized with tree lucerne and those with the 9-year old sole soil bund gave higher grain yields (1878.5 kg ha-1 and 1712.5 kg ha-1, respectively) than fields having 9-year old soil bund stabilized with vetiver grass (1187 kg ha-1) and 6-year old soil bund stabilized with tree lucerne (1284.25 kg ha-1). When we compare the accumulation and the loss zones, the average grain yield obtained from the accumulation zones (averaged over all the Lessons from Upstream Soil Conservation Measures to Mitigate Soil Erosion and its Impact on Upstream and Downstream Users of the Nile River.Length: pp.170-183ErosionLand degradationSoil conservationBundsWater conservationSoil properties

The local translation of KNa in dendritic projections of auditory neurons and the roles of KNa in the transition from hidden to overt hearing loss

Local and privileged expression of dendritic proteins allows segregation of distinct functions in a single neuron but may represent one of the underlying mechanisms for early and insidious presentation of sensory neuropathy. Tangible characteristics of early hearing loss (HL) are defined in correlation with nascent hidden hearing loss (HHL) in humans and animal models. Despite the plethora of causes of HL, only two prevailing mechanisms for HHL have been identified, and in both cases, common structural deficits are implicated in inner hair cell synapses, and demyelination of the auditory nerve (AN). We uncovered that N

Single-Cell RNA-seq Reveals Profound Alterations in Mechanosensitive Dorsal Root Ganglion Neurons with Vitamin E Deficiency.

Ninety percent of Americans consume less than the estimated average requirements of dietary vitamin E (vitE). Severe vitE deficiency due to genetic mutations in the tocopherol transfer protein (TTPA) in humans results in ataxia with vitE deficiency (AVED), with proprioceptive deficits and somatosensory degeneration arising from dorsal root ganglia neurons (DRGNs). Single-cell RNA-sequencing of DRGNs was performed in Ttpa-/- mice, an established model of AVED. In stark contrast to expected changes in proprioceptive neurons, Ttpa-/- DRGNs showed marked upregulation of voltage-gated Ca2+ and K+ channels in mechanosensitive, tyrosine-hydroxylase positive (TH+) DRGNs. The ensuing significant conductance changes resulted in reduced excitability in mechanosensitive Ttpa-/- DRGNs. A highly supplemented vitE diet (600 mg dl-α-tocopheryl acetate/kg diet) prevented the cellular and molecular alterations and improved mechanosensation. VitE deficiency profoundly alters the molecular signature and functional properties of mechanosensitive TH+ DRGN, representing an intriguing shift of the prevailing paradigm from proprioception to mechanical sensation

Transparent ferromagnetic and semiconducting behavior in Fe-Dy-Tb based amorphous oxide films

We report a class of amorphous thin film material comprising of transition (Fe) and Lanthanide metals (Dy and Tb) that show unique combination of functional properties. Films were deposited with different atomic weight ratio (R) of Fe to Lanthanide (Dy + Tb) using electron beam co-evaporation at room temperature. The films were found to be amorphous, with grazing incidence x-ray diffraction and x-ray photoelectron spectroscopy studies indicating that the films were largely oxidized with a majority of the metal being in higher oxidation states. Films with R = 0.6 were semiconducting with visible light transmission due to a direct optical band-gap (2.49 eV), had low resistivity and sheet resistance (7.15 × 10−4 Ω-cm and ~200 Ω/sq respectively), and showed room temperature ferromagnetism. A metal to semiconductor transition with composition (for R \u3c 11.9) also correlated well with the absence of any metallic Fe0oxidation state in the R = 0.6 case as well as a significantly higher fraction of oxidized Dy. The combination of amorphous microstructure and room temperature electronic and magnetic properties could lead to the use of the material in multiple applications, including as a transparent conductor, active material in thin film transistors for display devices, and in spin-dependent electronics

Use of rainfall indices to analyze the effects of phosphate rocks on millet in the Sahel

Two critical factors that explain low crop productivity in the Sahelian agro-ecozone are inadequate moisture and poor soils, particularly phosphorus (P) deficiency. The purpose of this long-term study was to explore the use of both local phosphate rock (PR) and inorganic P on yields and risk of millet returns under the uncertain rainfall regimes in the Sahel. Using the Standardized Precipitation Index (SPI) and Percent Confidence Limits (PCL) of the mean rainfall, the 10-year experimental period was grouped into rainfall classes. Results showed that the inorganic P fertilizers, that is, single superphosphate and triple superphosphate (SSP+N and TSP) gave the highest average yields. Also, millet yield increased with increasing P rates. However, typical farmers in the Sahel barely use P rates above 20 kg ha-1 in view of the high cost of imported fertilizers. A low application rate of the local PR, 10 kg P ha-1, increased millet yield between 44 and 67%. Stability analysis using yields from 15 farmers’ fields indicated that the traditional method of growing millet was the least stable (s.e. = 225) and had the lowest yield (314 kg ha-1). Generally, millet responded to P better when the preseason (May-June) were wet than dry, except where the non-acidulated PR (PRA) was applied every year (R2=0.99, P < 0.01) for both dry and wet preseasons. Risk analysis showed that acidulated PR regardless of rates gave the highest millet returns over variable cost of P fertilizer. The study recommends the promotion PR in order to guarantee stable yields and income for small farmers in the Sahel

Trend and stability analyses of millet yields treated with fertilizer and crop residues in the Sahel

Pearl millet (Penisetum glaucum (L.) R.Br.) is a major food crop grown on impoverished sandy soils in the Sahel. A 9-year long-term study was undertaken in the Sahel to test the hypothesis that integrated use of millet crop residues retained on farm fields after harvest and mineral fertilizers results in greater and more sustainable yields and conserve soil fertility better than either the use of residue or fertilizer alone. The four treatments compared were: (1) control (crop residue removed and no fertilizer applied), (2) crop residue alone, (3) 30 kg N+13 kg P ha-1 (fertilizer) alone and (4) crop residue+fertilizer. Use of crop residue+fertilizer increased grain yield fourfold over the control; use of fertilizer doubled millet yield relative to the control and crop residues resulted in 1.2 times more yield than the control. Crop residues significantly improved nutrient-use efficiency of the applied fertilizer. Sustainability yield index (SYI), a measure of an upward trend in yield over time, was greatest in crop residue+fertilizer plots as are soil organic carbon, available P and pH. Stability analysis indicated that crop residue+fertilizer treatment gave in greater yields and returns over fertilizer cost in the various seasons than either crop residue or fertilizer

Cooperativity of Kv7.4 channels confers ultrafast electromechanical sensitivity and emergent properties in cochlear outer hair cells.

The mammalian cochlea relies on active electromotility of outer hair cells (OHCs) to resolve sound frequencies. OHCs use ionic channels and somatic electromotility to achieve the process. It is unclear, though, how the kinetics of voltage-gated ionic channels operate to overcome extrinsic viscous drag on OHCs at high frequency. Here, we report ultrafast electromechanical gating of clustered Kv7.4 in OHCs. Increases in kinetics and sensitivity resulting from cooperativity among clustered-Kv7.4 were revealed, using optogenetics strategies. Upon clustering, the half-activation voltage shifted negative, and the speed of activation increased relative to solitary channels. Clustering also rendered Kv7.4 channels mechanically sensitive, confirmed in consolidated Kv7.4 channels at the base of OHCs. Kv7.4 clusters provide OHCs with ultrafast electromechanical channel gating, varying in magnitude and speed along the cochlea axis. Ultrafast Kv7.4 gating provides OHCs with a feedback mechanism that enables the cochlea to overcome viscous drag and resolve sounds at auditory frequencies

Standardized precipitation index and nitrogen rate effects on crop yields and risk distribution in

Abstract Crop performance in rainfed cropping systems generally is dependent on rainfall amount and distribution. The objective of this study was to analyze the long-term consequences of rainfall expressed as a standardized precipitation index (SPI) and fertilizer nitrogen (N) on yields and risk probabilities of maize in the udic-ustic moisture regimes in the Great Plains in Nebraska. The SPI is a precipitation index for classifying drought stress conditions. The study was conducted on a Kennebec silt loam (Cumulic Hapludoll) over an 11-year period, 1986-1996, using monoculture maize (Zea mays L.) and maize in rotation with soybean (Glycine max.(L.) Merr.) in combination with N fertilizer levels between 0 and 160 kg ha −1 . Maize yields in monoculture ranged from 4.8 to 5.7 Mg ha −1 , and from 6.4 to 6.8 Mg ha −1 in rotation. The differences in yields between monoculture and rotation were larger at low N rates and decreased as N fertilizer increased above 40 kg ha −1 . Current year&apos;s maize yields either exhibited a weak or no response to N fertilizer in years when the preceding preseason (October-April) and the previous growing season (May-August) were dry (negative SPI value). Regression of yield as the dependent variable and the 12-month April SPI as the independent variable explained up to 64% of yield variability in a curvilinear relationship. Optimum SPI values were in the range of −1.0 to 1.0, substantiating the adaptability and performance of crops under mild stress as proposed by other scientists. Prediction of subsequent yields using past SPI data was relatively better in rotations (R 2 =41-50%) than in monoculture (R 2 =15-40%). Risk, calculated as the lower confidence limit of maize returns over variable cost of fertilizer, was less in rotations than in monoculture, and in both cropping systems returns were maximized with the application of N fertilizer at 40 kg ha −1 . Used with other criteria, the SPI can be a practical guide to choice of crops, N levels, and management decisions to conserve water in rainfed systems

Simulated weather variables effects on millet fertilized with phosphate rock in the Sahel

The Sudano–Sahelian agroecological zone is characterized by low and variable rainfall regimes and P deficiency. The present study complements previous research efforts and the objective was (i) to use the Newhall Simulation Model (NSM) to characterize three ICRISAT research sites, and (ii) to use output of NSM to develop an empirical model to guide efficient use of rainfall and fertilizers. The results show that length of the periods that rainfall exceeded evapotranspiration was larger in Bengou than in Gobery and Sadoré. Total positive moisture balance during the three growing seasons was 85.7 mm at Bengou and 19.7 mm at Sadoré. The model explained 52% of the variability in millet yields based on curvilinear response to P fertilizer, standardized May–June (Rmj) rainfall, and the number of wet days in the year (BW3). Yields appear more sensitive to BW3 than to Rmj. Their respective elasticity coefficients (E c ) were 0.62 and 0.09. Assessment of the model using R2=0.76 and the D-index = 0.85 showed reasonable agreement between model estimation and actual field yields. The study demonstrates the application of simulation models as a cost-effective means in terms of time and funds to agronomic researc

Altered outer hair cell mitochondrial and subsurface cisternae connectomics are candidate mechanisms for hearing loss in mice

Organelle crosstalk is vital for cellular functions. The propinquity of mitochondria, ER, and plasma membrane promote regulation of multiple functions, which include intracellular C