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Due to the advance of mobile technology, use of mobile devices such as smartphones has been growing rapidly in the U.S. and worldwide. Many health related mobile apps have been developed for care professionals and patients as well. However, studies indicate that there is a gap between science and commercially developed mobile apps. In addition to this, there is no framework to guide devlopment of a mobile app to overcome many challenges and obstacles. Through the development of a pain management mobile app for cancer patients, a framework was developed. A proposed framework was based on the technology acceptance model, ensuring usefulness and ease of use for end users. The first two steps in the framework enforce accurate knowledge translation and communication to build a science based mobile app. Iterative decisions points between steps enhance accomplishment of each step. [ABSTRACT FROM AUTHOR]

Objective: To compare the performance of one-view digital breast tomosynthesis (DBT) and two-view full-field digital mammography (FFDM) in the detection and characterization of breast lesions in a selective diagnostic population. Methods: A total of 598 breasts of 319 diagnostic patients were prospectively enrolled. Participants underwent bilateral one-view, mediolateral oblique (MLO) DBT and two-view, craniocaudal and MLO FFDM. The sensitivity and specificity of these methods and their classification into correct Breast Imaging-Reporting and Data System (BI-RADS) categories were compared. These methods were also compared in patients subgrouped by mammographic parenchymal density. Receiver operating characteristic (ROC) curve analysis was performed using the probability of cancer scores. Results: DBT had higher overall sensitivity than FFDM (88.7% vs 80.7%, p - 0.001). Subgroup analyses showed that DBT had significantly higher sensitivity in assessing dense breasts and invasive cancers than FFDM. The BI-RADS category assessment was significantly better for DBT than for FFDM. The differences between the two modalities in specificity (94.1% and 93.2% for FFDM and DBT) were not significant (p = 0.664). The area under the ROC curves using the probability of cancer scores were 0.93 [95% confidence interval (Ci), 0.91-0.95] for FFDM and 0.96 (95% Cl, 0.94-0.97) for DBT (p = 0.005). ROC curve analysis indicated that most of the increased performance of DBT was due to dense breasts. Conclusion: A beneficial effect on the detection and characterization of breast lesions was found for one-view DBT compared with two-view FFDM in a selective diagnostic population. Improvements were especially enhanced in females with dense breasts. These results need to be examined in studies using large-scale consecutive sampling of a diagnostic population. Advances in knowledge: In this study, using selective diagnostic study cases, one-view DBT offered improved reader performance compared with two-view FFDM for detection and characterization of breast cancers. [ABSTRACT FROM AUTHOR]

Primary breast melanoma is extremely rare, and as such, there are no established radiologic findings in the literature. This report describes a case of primary malignant melanoma with mammography, ultrasonography, and magnetic resonance imaging findings. Our case study demonstrates a well-circumscribed heterogeneous rim-enhancing mass, with an internal cystic or necrotic portion seen using three modalities. Thus, although rare, this condition should be included in the differential diagnosis of a well-demarcated heterogeneous breast mass, and further pathological confirmation is needed. [ABSTRACT FROM AUTHOR]

Purpose: The chemistry of annual tree growth rings is affected by precipitation pH, and tree rings store information on environmental conditions at the time of ring formation. The purpose of this study was to evaluate the potential use of tree ring chemistry data in estimating historical precipitation pH using the relationship between precipitation pH and tree ring chemistry. Materials and methods: Red pine ( Pinus densiflora) stem disks were collected from a forest in southern Korea and analyzed for C isotope ratio (C/C, expressed as δC), N concentration, N isotope ratio (N/N, expressed as δN), and molar Ca/Al in annual growth rings. Correlation analysis was conducted for the relationship between tree ring chemistry and precipitation pH between 1992 and 2005 for which such data were available. A regression equation between precipitation pH and tree ring chemistry was then developed using stepwise multiple regression analysis. Results and discussion: We found that between 1992 and 2005, δN (−0.4‰ to −2.7‰) and Ca/Al (11.6 to 7.3) decreased in the growth rings (all significant at α = 0.05) with precipitation pH decreased from 5.7 to 5.0, while the amount of NO emission increased from 12.7 to 22.1 thousand tons between 1999 and 2005 in the study area. The decreased δN and Ca/Al in the tree rings associated with the decreasing precipitation pH seemed to reflect increased N deposition originated from NO emission that is known to be depleted in N relative to the soil mineral N and reduction in Ca availability due to soil acidification. The regression model indicated that mean annual precipitation pH values before the late 1990s at the study site fluctuated between 5.5 and 6.8; thereafter, it showed a decreasing pattern below 5.4 (the lowest measured and estimated pHs were 5.2 and 5.0, respectively) in the mid-2000s with increasing NO emission. Conclusions: The significant correlation of precipitation pH with δN and Ca/Al in tree rings suggested that it may be possible to use tree ring chemistry to estimate historical precipitation pH. However, δC and N concentration of tree rings were not useful as indicators of acid precipitation in this study, as δC is an integrator of many environmental factors that affect gas exchange and inter-ring movement of N towards the outermost ring may mask time-related information regarding N availability. Further research is needed to validate the model in regions where long-term precipitation pH records are available. [ABSTRACT FROM AUTHOR]

Effects of elevated CO concentration ([CO]) and air temperature (T) on accumulation and intra-plant partitioning of dry matter (DM) and nitrogen in paddy rice were investigated by performing a pot experiment in six natural sunlit temperature gradient chambers (TGCs) with or without CO fumigation. Rice ( Oryza sativa L.) plants were grown in TGCs for a whole season under two levels of [CO] (ambient, 380 ppm; elevated, 622 ppm) and two daily T regimes (ambient, 25.2°C; elevated, 27.3°C) in split-plot design with triplication. The effects of elevated [CO] and T on DM were most dramatic for grain and shoot with a significant ( P < 0.05) interaction between [CO] and T. Overall, total grain DM increased with elevated [CO] by 69.6% in ambient T but decreased with elevated T by 33.8% in ambient [CO] due to warming-induced floral sterility. Meanwhile, shoot DM significantly increased with elevated T by 20.8% in ambient [CO] and by 46.6% in elevated [CO]. Although no [CO] × T interaction was detected, the greatest total DM was achieved by co-elevation of [CO] and T (by 42.8% relative to the ambient conditions) via enhanced shoot and root DM accumulation, but not grain. This was attributed largely both to increase in tiller number and to accumulation of photosynthate in the shoot and root due to inhibition of photosynthate allocation to grain caused by warming-induced floral sterility. Distribution of N (both soil N and fertilizer N) among rice parts in responding to climatic variables entirely followed the pattern of DM. Our findings demonstrate that the projected warming is likely to induce a significant reduction in grain yield of rice by inhibiting DM (i.e., photosynthates) allocation to grain, though this may partially be mitigated by elevated [CO]. [ABSTRACT FROM AUTHOR]

Purpose: To more efficiently utilize composts as N sources while minimizing the environmental impact, it is necessary to understand the effects of compost type on N mobility in compost-amended soil with different characteristics. The objectives of this study are to investigate the effects of livestock manure composts on N leaching from soils and to identify the principal physicochemical variables of the composts that affect N leaching. Materials and methods: A combination leaching-incubation experiment using seven livestock manure composts and three soils (Inceptisol, Ultisol, and Andisol) with different characteristics was conducted for 19 weeks. Leachates were collected periodically and analyzed for various forms of N (NH, NO, organic N, and total N). The effects of compost type on N leaching were assessed by analysis of variance and correlation between N leaching amounts and compost variables (pH, total C, total N, C/N, and various forms of extractable N). Results and discussion: Initial flush of N leaching at the first leaching event conducted after 1-week incubation was observed probably due to mineralization of readily decomposable N pool; the amount of N leached at 1-week incubation accounted for more than 50% of cumulative amount of N leached through 19-week incubation. Among the various compost variables tested, only total N concentration of compost was significantly ( P < 0.05) correlated with total N and mineral N (NH + NO) leached across all three soils, indicating that total N concentration of composts is the common factor affecting N leaching from the compost-amended soils. Comparing amongst the three soils, the cumulative amount of total N leached increased in the order of Andisol (34.5 to 103.4 mg N) > Ultisol (33.9 to 64.7 mg N) > Inceptisol (12.8 to 31.7 mg N) being affected by soil N availability. Conclusions: The significant effects of compost and soil types suggested that not only soils but also composts characteristics needs to be considered when establishing the compost application guidelines. Particularly when compost characteristics are considered, total N rather than the mineral N concentration of composts can be used to predict the N leaching potential in composts-amended soils. [ABSTRACT FROM AUTHOR]

When synthetic fertilizer is co-applied with composted manure (compost), the high urease activity of compost may stimulate urea hydrolysis, thus increasing NH3 volatilization when urea is co-applied as a synthetic fertilizer. In this study, the interactive effects of compost type (low vs. high urease activity, referred to as CL and CH, respectively) and synthetic fertilizer form (urea vs. ammonium sulfate) were assessed in a 60-day greenhouse study. The compost was applied as a basal fertilization only at the initiation of the experiment, and the fertilizers (15N labeled or not) were split into basal and additional fertilization. During the 10 days after the basal fertilization, co-application of CL with urea did not increase NH3 volatilization as compared with urea alone treatment. However, co-application of CH with urea resulted in a significant increase in NH3 volatilization by more than 3-fold, not only from applied fertilizer-15N but also from compost and/or soil over the other two (urea alone and urea with CL) treatments. Meanwhile, when ammonium sulfate was co-applied with CH, NH3 volatilization from fertilizer became 3-fold lower than that when urea was co-applied. During the second 10 days after the application of urea as an additional fertilizer, the amount of NH3 volatilization from CH-treated soil did not differ from that observed with CL, and this is probably attributable to a reduction in urease activity in soils over time. These results indicate that not only the combination of compost and synthetic fertilizer, but also the time difference between the application of compost and synthetic fertilizer, are crucial to reducing NH3 volatilization. [ABSTRACT FROM AUTHOR]

A laboratory incubation was conducted to evaluate nitrous oxide (N2O) production during nitrification and the effect of a nitrification inhibitor on N2O production from different profiles in a Japanese orchard Andosol. Soils were collected from five profiles: A1, A2, Bw1, Bw2, and BC. The soils were treated with ammonium sulfate at the rate of 200 mg N kg-1 with or without dicyandiamide (DCD) and incubated under aerobic conditions for 32 days. The net nitrification rate without DCD during the first 8 days was greater in the surface soils than in the subsurface soils. Accordingly, the surface soils showed a greater cumulative N2O production than the subsurface soils. Application of DCD significantly reduced the nitrification rate and thus N2O production from any depths of soils by 33.8 to 62.9%. Our study showed that substantial N2O was produced from the subsurface soil, although the amount was less than from the surface soils. [ABSTRACT FROM AUTHOR]

The lowering of the water table resulting from peatland drainage may dramatically alter C and N cycling in peatland ecosystems, which contain one-third of the total terrestrial C. In this study, tree annual ring width and C (δ13C) and N (δ15N) isotope ratios in soil and plant tissues (tree foliage, growth rings, and understory foliage) in a black spruce-tamarack (Picea mariana-Larix laricina) mixed-wood forest were examined to study the effects of drainage on tree growth and C and N dynamics in a minerotrophic peatland in west-central Alberta, Canada. Drainage increased the δ15N of soil NH4+ from a range of +0.6‰ to +2.9‰ to a range of +4.6‰ to +7.0‰ most likely through increased nitrification following enhanced mineralization. Plant uptake of 15N-enriched NH4+ in the drained treatment resulted in higher plant δ15N (+0.8‰ to +1.8‰ in the drained plots and -3.9‰ to -5.4‰ in the undrained plots), and deposition of litterfall N enriched with 15N increased the δ15N of total soil N in the surface layer in the drained (+2.9‰) as compared with that in the undrained plots (+0.6‰). The effect of drainage on foliar δ13C was species-specific, i.e., only tamarack showed a considerably less negative foliar δ13C in the drained (-28.1‰) than in the undrained plots (-29.1‰), indicating improved water use efficiency (WUE) by drainage. Tree ring area increments were significantly increased following drainage, and δ13C and δ15N in tree growth rings of both species showed responses to drainage retrospectively. Tree-ring δ13C data suggested that drainage improved WUE of both species, with a greater and more prolonged response in tamarack than in black spruce. Our results indicate that drainage caused the studied minerotrophic peatland to become a more open ecosystem in terms of C and N cycling and loss. The effects of forested peatland drainage or drying on C and N balances deserve further research in order to better understand their roles in future global change. [ABSTRACT FROM AUTHOR]

Nitrogen (N) concentrations and stable N isotope abundances (δ15N) of common reed (Phragmites australis) planted in a constructed wetland were measured periodically between July 2001 and May 2002 to examine their seasonal variations in relation to N uptake and N translocation within common reed. Nitrogen concentrations in P. australis shoots were higher in the growing stage (7.5 to 24.8 g N kg-1)than in the senescence stage (4.2 to 6.8 g N kg-1), indicating N translocation from shoots to rhizomes. Meanwhile, the corresponding δ15N values were higher in the senescence stage (+12.2 to +22.4‰) than in the growing stage (+5.1 to +11.3‰). Coupled with the negative correlation (R² 0.24, P < 0.05, n 18) between N concentrations and δ15N values of shoots in the senescence stage, our results suggested that shoot N became enriched in δ15N due to N isotopic fractionation (with an isotopic fractionation factor, αs/p' of 1.012) during N translocation to rhizomes. However, the positive correlation between N concentrations and δ15N values in the growing stage (R² 0.19, P < 0.001, n 54) suggested that P. australis relies on N re-translocated from rhizome in the early growing stage and on mineral N in the sediment during the active growing stage. Therefore, seasonal δ15N variations provide N-isotopic evidence of N translocation within and N uptake from external N sources by common reed. [ABSTRACT FROM AUTHOR]

Natural abundances of carbon-13 and nitrogen-15 were analyzed in 3-year bands of annual rings of three red pine ( Pinus densiflora Sieb. et Zucc.) trees in eastern Korea to elucidate their variations in relation to changing environmental conditions, particularly air pollution. Tree ring width had a trend to decrease with time ( r = −0.79, P < 0.001); however, tree-ring indices did not show any consistent pattern of change over time. Tree ring indices were correlated neither with the respective precipitation nor temperature. The δ13C (range: −25.7 to −24.4ä) of tree rings became less negative as tree ring indices increase ( r = 0.43, P < 0.05), suggesting that radial growth of trees might have been affected by environmental factors such as nutrient deficiency and acid rain that affect carboxylation efficiency. Increasing N concentration (range: 0.40 to 0.68 g N kg−1) with decreasing δ15N (range: +4.2 to −0.6ä) of tree rings ( r = −0.84, P < 0.01) during the period (since 1980s) of increasing NO x emission in Korea was consistent with the hypothesis that increasing deposition of N depleted in 15N may lead to 15N depletion in tree tissues. However, quantitative information on inter-ring translocation of N which may cause N isotopic fractionation is necessary to use the δ15N signal as a reliable indicator of air pollution. [ABSTRACT FROM AUTHOR]

Many experiments conducted under controlled environmental conditions suggest that deciduous tree species are adapted to NO3– rather than NH4+ uptake. To test this under field conditions, we studied soil retention, tree uptake, and tree resorption of 15N derived from either 15NH4NO3 or NH415NO3 applied to trembling aspen (Populus tremuloides Michx.) and hybrid aspen (Populus tremula L. × P. tremuloides) at planting. Overall, the hybrid had greater dry-matter yield and took up more total N than the trembling aspen over two growing seasons after fertilization. The recovery of 15N per tree was also higher for the hybrid aspen than for the trembling aspen. Trembling aspen showed higher resorption efficiency of foliage N before abscission than hybrid aspen; however, the total amount of N retranslocated before leaf senescence was the reverse because of higher foliar dry-matter yield of hybrid aspen. The higher recovery of 15NH4+ than 15NO3– by trees seemed to be governed by higher N retention potential of NH4+ than NO3– in the soil. These results suggest that fertilization strategies need to be made based on both N acquisition capability of species and site-related factors, such as soil pH and immobilization–mineralization potential. [ABSTRACT FROM AUTHOR]

Interactive effects of a combined application of urea and compost on the fates of urea-N and net mineralization of compost-N in three soils with different contents of organic-C and inorganic-N were examined through an aerobic 6-week incubation study. Soils were each subjected to four treatments of urea and compost applied at rates of 0 and 0 mg N kg -1 (control), 115 and 0 mg N kg -1, 0 and 115 mg N kg -1, and 70 and 45 mg N kg -1, respectively. The interactive effects of a combined application of compost and urea on their N transformations varied depending on the contents of indigenous inorganic-N and organic-C in soils. Urea hydrolysis was increased by compost blending only in soils with a relatively low organic-C content. Compost blending increased N immobilization, thus decreasing nitrification of urea-derived N in soils with high organic-C and inorganic-N contents, whereas the reverse was observed in soils with low nutrient contents. Urea blending, by providing inorganic-N, consistently increased net mineralization of compost-N irrespective of soil characteristics, although the increase was much smaller in soil with high indigenous inorganic-N. From the results, it could be concluded that a combined application of chemical fertilizer would improve the compost use efficiency by increasing mineralization of compost-N particularly in soil with a low inorganic-N content. This study also suggests that compost blending would increase immobilization of urea-N in soils with high C and N contents, whereas it would increase nitrification of fertilizer-N in soils with low nutrients contents, thus resulting in increased NO 3 - leaching. [ABSTRACT FROM AUTHOR]

Diagnostic tests for organic production of crops would be useful. In this study, the difference in natural 15N abundances (δ15N) of soils and plants between fertilizer-applied upland (FU) and compost-applied upland (CU) fields was investigated to study using δ15N as a marker of organic produce. Twenty samples each of soils and plants were collected from each field in early summer after applying fertilizer or compost. The δ15N of fertilizers and composts was −1.6±1.5‰ (n=8) and 17.4±1.2‰ (n=10), respectively. The δ15N of total soil-N was significantly (P<0.05) higher in CU fields (8.8±2.0‰) than in FU fields (5.9±0.7‰) due to long-term continuous application of 15N-enriched compost, as indicated by a positive correlation (r=0.62) between N content and δ15N of total soil-N. The NO3− pool of CU soils (11.6±4.5‰) was also significantly (P<0.05) enriched in 15N compared to FU soils (4.7±1.1‰), while the 15N contents of NH4+ pool were not different between both soils. Compost application resulted in 15N enrichment of plants; the δ15N values were 14.6±3.3‰ for CU and 4.1±1.7‰ for FU fields. These results showed that long-term application of compost resulted in a significant 15N-enrichment of soils and plants relative to fertilizer. Therefore, this study suggested that δ15N could serve as promising indicators of organic fertilizers application when used with other independent evidence. However, further studies under many conditions should be conducted to prepare reliable δ15N guidelines for organic produce, since the δ15N of inorganic soil-N and plant-N are influenced by various factors such as soil type, plant species, the rate of N application, and processes such as mineralization, nitrification, and denitrifcation. [Copyright &y& Elsevier]

This study was conducted to examine whether the applications of N-inputs (compost and fertilizer) having different N isotopic compositions (δ15N) produce isotopically different inorganic-N and to investigate the effect of soil moisture regimes on the temporal variations in the δ15N of inorganic-N in soils. To do so, the temporal variations in the concentrations and the δ15N of NH4+ and NO3− in soils treated with two levels (0 and 150 mg N kg−1) of ammonium sulfate (δ15N=−2.3‰) and compost (+13.9‰) during a 10-week incubation were compared by changing soil moisture regime after 6 weeks either from saturated to unsaturated conditions or vice versa. Another incubation study using 15N-labeled ammonium sulfate (3.05 15N atom%) was conducted to estimate the rates of nitrification and denitrification with a numerical model FLUAZ. The δ15N values of NH4+ and NO3− were greatly affected by the availability of substrate for each of the nitrification and denitrification processes and the soil moisture status that affects the relative predominance between the two processes. Under saturated conditions for 6 weeks, the δ15N of NH4+ in soils treated with fertilizer progressively increased from +2.9‰ at 0.5 week to +18.9‰ at 6 weeks due to nitrification. During the same period, NO3− concentrations were consistently low and the corresponding δ15N increased from +16.3 to +39.2‰ through denitrification. Under subsequent water-unsaturated conditions, the NO3− concentrations increased through nitrification, which resulted in the decrease in the δ15N of NO3−. In soils, which were unsaturated for the first 6-weeks incubation, the δ15N of NH4+ increased sharply at 0.5 week due to fast nitrification. On the other hand, the δ15N of NO3− showed the lowest value at 0.5 week due to incomplete nitrification, but after a subsequence increase, they remained stable while nitrification and denitrification were negligible between 1 and 6 weeks. Changing to saturated conditions after the initial 6-weeks incubation, however, increased the δ15N of NO3− progressively with a concurrent decrease in NO3− concentration through denitrification. The differences in δ15N of NO−3 between compost and fertilizer treatments were consistent throughout the incubation period. The δ15N of NO3− increased with the addition of compost (range: +13.0 to +35.4‰), but decreased with the addition of fertilizer (−10.8 to +11.4‰), thus resulting in intermediate values in soils receiving both fertilizer and compost (−3.5 to +20.3‰). Therefore, such differences in δ15N of NO3− observed in this study suggest a possibility that the δ15N of upland-grown plants receiving compost would be higher than those treated with fertilizer because NO3− is the most abundant N for plant uptake in upland soils. [Copyright &y& Elsevier]

Studies the effect of combined application of composted pig manure and urea containing 15N, an isotope of nitrogen, on the availability of urea for corn with the help of an experiment. Technique used to measure urea-nitrogen uptake efficiency of corn; Possibility of an increase in corn uptake of nitrogen in soil or nitrogen in compost; Reason for low uptake efficiency of urea-nitrogen by corn.