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Data-driven irrigation planning can optimize crop yield and reduce adverse impacts on surface and ground water quality. We evaluated an irrigation scheduling strategy based on soil matric potentials recorded by wireless Watermark (WM) sensors installed in sandy loam and clay loam soils and soil-water characteristic curve data. Five wireless WM nodes (IRROmesh) were installed at each location, where each node consisted of three WM sensors that were installed at 15, 30, and 60 cm depths in the crop rows. Soil moisture contents, at field capacity and permanent wilting points, were determined from soil-water characteristic curves and were approximately 23% and 11% for a sandy loam, and 35% and 17% for a clay loam, respectively. The field capacity level which occurs shortly after an irrigation event was considered the upper point of soil moisture content, and the lower point was the maximum soil water depletion level at 50% of plant available water capacity in the root zone, depending on crop type, root depth, growth stage and soil type. The lower thresholds of soil moisture content to trigger an irrigation event were 17% and 26% in the sandy loam and clay loam soils, respectively. The corresponding soil water potential readings from the WM sensors to initiate irrigation events were approximately 60 kPa and 105 kPa for sandy loam, and clay loam soils, respectively. Watermark sensors can be successfully used for irrigation scheduling by simply setting two levels of moisture content using soil-water characteristic curve data. Further, the wireless system can help farmers and irrigators monitor real-time moisture content in the soil root zone of their crops and determine irrigation scheduling remotely without time consuming, manual data logging and frequent visits to the field.

Protein kinase C δ (PKCδ) regulates apoptosis in the mammary gland, however, the functional contribution of PKCδ to the development or progression of breast cancer has yet to be determined. Meta-analysis of ErbB2-positive breast cancers shows increased PKCδ expression, and a negative correlation between PKCδ expression and prognosis. Here, we present in-vivo evidence that PKCδ is essential for the development of mammary gland tumors in a ErbB2-overexpressing transgenic mouse model, and in-vitro evidence that PKCδ is required for proliferative signaling downstream of the ErbB2 receptor. Mouse mammary tumor virus (MMTV)-ErbB2 mice lacking PKCδ (δKO) have increased tumor latency compared with MMTV-ErbB2 wild-type (δWT) mice, and the tumors show a dramatic decrease in Ki-67 staining. To explore the relationship between PKCδ and ErbB2-driven proliferation more directly, we used MCF-10A cells engineered to express a synthetic ligand-inducible form of the ErbB2 receptor. Depletion of PKCδ with short hairpin RNA inhibited ligand-induced growth in both two-dimensional (2D) (plastic) and three-dimensional (3D) (Matrigel) culture, and correlated with decreased phosphorylation of the ErbB2 receptor and reduced activation of Src and MAPK/ERK pathways. Similarly, in human breast cancer cell lines in which ErbB2 is overexpressed, depletion of PKCδ suppresses proliferation, Src and ERK activation. PKCδ appears to drive proliferation through the formation of an active ErbB2/PKCδ/Src signaling complex, as depletion of PKCδ disrupts association of Src with the ErbB2 receptor. Taken together, our studies present the first evidence that PKCδ is a critical regulator of ErbB2-mediated tumorigenesis, and suggest further investigation of PKCδ as a target in ErbB2-positive breast cancer.

Compost derived from landscape debris was incorporated into seven different soils in the Dallas, Texas area at variable rates. Treatment levels for each of the 3.34 m 2 quadrats were compost depths of approximately 0.0, 2.5, 5.0 and 7.5 cm. Composted plots were evaluated for two years to quantify differences in infiltration rate, moisture content, coefficient of linear extensibility (COLE), pH and salinity relative to control plots. Substantial differences in soil properties between sites barred comparison between sites. However, significant site-specific differences between control and treatments were observed. Infiltration rate was more strongly affected by soil texture, soil mineralogy, and climatic effects than by the addition of compost. Compost incorporation may provide a significant reduction in COLE values, but not necessarily to levels below the \"very high\" shrink/swell class. Soil water content significantly increased with elevated levels of compost in the Austin, Eddy, and Brackett soils. Incorporated landscape compost does provide quantifiable benefits to soil physical properties on certain soil series in the Dallas area.

Excessive manure phosphorus (P) application increases risk of P loss from fields. This study assessed total runoff P (TPR), bioavailable P (BAP), and dissolved reactive P (DRP) concentrations and loads in surface runoff after liquid swine (Sus scrofa domesticus) manure application with or without incorporation into soil and different timing of rainfall. Four replicated manure P treatments were applied in 2002 and in 2003 to two Iowa soils testing low in P managed with corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotations. Total P applied each time was 0 to 80 kg P ha-1 at one site and 0 to 108 kg P ha-1 at the other. Simulated rainfall was applied within 24 h of P application or after 10 to 16 d and 5 to 6 mo. Nonincorporated manure P increased DRP, BAP, and TPR concentrations and loads linearly or exponentially for 24-h and 10- to 16-d runoff events. On average for the 24-h events, DRP, BAP, and TPR concentrations were 5.4, 4.7, and 2.2 times higher, respectively, for nonincorporated manure than for incorporated manure; P loads were 3.8, 7.7, and 3.6 times higher; and DRP and BAP concentrations were 54% of TPR for nonincorporated manure and 22 to 25% for incorporated manure. A 10- to 16-d rainfall delay resulted in DRP, BAP, and TPR concentrations that were 3.1, 2.7, and 1.1 times lower, respectively, than for 24-h events across all nonincorporated P rates, sites, and years, whereas runoff P loads were 3.8, 3.6, and 1.6 times lower, respectively. A 5- to 6-mo simulated rainfall delay reduced runoff P to levels similar to control plots. Incorporating swine manure when the probability of immediate rainfall is high reduces the risk of P loss in surface runoff; however, this benefit sharply decreases with time.

Satellite telemetry is an increasingly utilized technology in wildlife research, and current devices can track individual animal movements at unprecedented spatial and temporal resolutions. However, as we enter the golden age of satellite telemetry, we need an in-Depth understanding of the main technological, species-specific and environmental factors that determine the success and failure of satellite tracking devices across species and habitats. Here, we assess the relative influence of such factors on the ability of satellite telemetry units to provide the expected amount and quality of data by analyzing data from over 3,000 devices deployed on 62 terrestrial species in 167 projects worldwide. We evaluate the success rate in obtaining GPS fixes as well as in transferring these fixes to the user and we evaluate failure rates. Average fix success and data transfer rates were high and were generally better predicted by species and unit characteristics, while environmental characteristics influenced the variability of performance. However, 48% of the unit deployments ended prematurely, half of them due to technical failure. Nonetheless, this study shows that the performance of satellite telemetry applications has shown improvements over time, and based on our findings, we provide further recommendations for both users and manufacturers.

Satellite telemetry is an increasingly utilized technology in wildlife research, and current devices can track individual animal movements at unprecedented spatial and temporal resolutions. However, as we enter the golden age of satellite telemetry, we need an in-Depth understanding of the main technological, species-specific and environmental factors that determine the success and failure of satellite tracking devices across species and habitats. Here, we assess the relative influence of such factors on the ability of satellite telemetry units to provide the expected amount and quality of data by analyzing data from over 3,000 devices deployed on 62 terrestrial species in 167 projects worldwide. We evaluate the success rate in obtaining GPS fixes as well as in transferring these fixes to the user and we evaluate failure rates. Average fix success and data transfer rates were high and were generally better predicted by species and unit characteristics, while environmental characteristics influenced the variability of performance. However, 48% of the unit deployments ended prematurely, half of them due to technical failure. Nonetheless, this study shows that the performance of satellite telemetry applications has shown improvements over time, and based on our findings, we provide further recommendations for both users and manufacturers.

Total soil P (TP), soil-test P (STP), and the degree of soil P saturation are affected by long-term P application but relationships between these measurements need to be established for grain production cropping systems to improve P management guidelines. This research studied these relationships from samples collected from 11 long-term (4-23 yr) Iowa P trials. Mean soil clay content and pH (0- to 15-cm depth) ranged from 171 to 375 g kg(-1) and 6.1 to 6.8, respectively, and maximum cumulative P application was 192 to 1098 kg P ha(-1). Soil was analyzed for Bray-P1 (BP), Mehlich-3 P (M3P), Olsen P (OP), TP, P sorption index (PSI), and P saturation by STP/PSI and Mehlich-3 extractable P, Al, and Fe (M3sat) indices. Soil-test P increased as P applied increased and declined when P was not applied. Total P increased linearly with increasing BP, M3P, and OP (r = 0.52-0.55), and increases were 1.8, 1.7, and 3.5 mg TP kg(-1) per mg STP kg(-1) for BP, M3P, and OP, respectively. Usually STP was linearly correlated to M3sat and STP/PSI (r = 0.80-0.94), and M3sat was linearly correlated to STP/PSI (r = 0.86-0.92). Results indicate that STP can approximately estimate long-term effects of P application on TP, and soil P saturation for conditions similar to those in this study, but TP estimates are improved by grouping similar soil series. Further research for a wider range of soils and STP would be useful to better describe relationships between these measurements.

Excessively high soil P can increase P loss with surface runoff. This study used indoor rainfall simulations to characterize soil and runoff P relationships for five Midwest soils (Argiudoll, Calciaquaoll, Hapludalf, and two Hapludolls). Topsoil (15-cm depth, 241-289 g clay kg(-1) and pH 6.0-8.0) was incubated with five NH4H2PO4 rates (0-600 mg P kg(-1)) for 30 d. Total soil P (TPS) and soil-test P (STP) measured with Bray-P1 (BP), Mehlich-3 (M3P), Olsen (OP), Fe-oxide-impregnated paper (FeP), and water (WP) tests were 370 to 1360, 3 to 530, 10 to 675, 4 to 640, 7 to 507, and 2 to 568 mg P kg(-1), respectively. Degree of soil P saturation (DPS) was estimated by indices based on P sorption index (PSI) and STP (DPS(STP)) and P, Fe, and Al extracted by ammonium oxalate (DPS(ox)) or Mehlich-3 (DPS(M3)). Soil was packed to 1.1 g cm(-3) bulk density in triplicate boxes set at 4% slope. Surface runoff was collected during 75 min of 6.5 cm h(-1) rain. Runoff bioavailable P (BAP) and dissolved reactive P (DRP) increased linearly with increased P rate, STP, DPS(ox), and DPS(M3) but curvilinearly with DPS(STP). Correlations between DRP or BAP and soil tests or saturation indices across soils were greatest (r greater than or equal to 0.95) for FeP, OP, and WP and poorest for BP and TPS (r = 0.83-0.88). Excluding the calcareous soil (Calciaquoll) significantly improved correlations only for BP. Differences in relationships between runoff P and the soil tests were small or nonexistent among the noncalcareous soils. Routine soil P tests can estimate relationships between runoff P concentration and P application or soil P, although estimates would be improved by separate calibrations for calcareous and noncalcareous soils.

Calcretes (petrocalcic horizons) are widespread indurated accumulations of carbonate in arid and semiarid regions of the world. Many studies have detailed the formation of these calcretes; however, little direct attention has been given to their degradation. The primary objective of this study was to evaluate the continuity of calcrete on the Llano Estacado as a step toward understanding processes of calcrete degradation across the region. The Llano Estacado is a tableland spanning eastern New Mexico and West Texas with a well-developed calcrete, known as the \"caprock,\" exposed as an escarpment around most of its perimeter. We excavated several deep pits along a transect between the caprock on the eastern margin of the Llano Estacado and a similar outcrop on a playa slope. We documented degradation features in the calcrete and compared the extent of degradation with a calcrete in a more arid region (Diablo Plateau). Our findings show a lack of continuity of the calcrete on the Llano Estacado even in a relatively short transect (220 m) between the two outcrops. Individual calcrete fragments showed evidence of partial dissolution. These observations were confirmed in road cuts and pits excavated for road material across the area. Geomorphic position and surface slope control water movement across the landscape and apparently explain both the variation in the presence of degradational features and the distribution of calcrete fragments in the transect. Observations from the more arid Diablo Plateau suggest that calcrete degradation is widespread. The degradation of calcrete on the Llano Estacado makes the caprock unreliable in some areas as a stratigraphic marker in distinguishing the Ogallala and Blackwater Draw Formations.