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Background Currently, the BREAST-Q can effectively measure patient's satisfaction on the quality of life from the patient's perspective in relation to different type of breast reconstruction. However, evaluation of patient satisfaction and cosmetic outcomes in breast reconstruction may have potential to led bias. Methods To maximize the benefits of using BREAST-Q to evaluate clinical outcome, we performed comparative study focused on the correlation between postoperative BREAST-Q and cosmetic outcomes assessed by medical professionals. For the current analysis, we used three postoperative BREAST-Q scales (satisfaction with breast, psychosocial well-being, and sexual well-being). The Ten-Point Scale by Visser et al was applied to provide reproducible grading of the postoperative cosmetic outcomes of the breast. The system includes six subscales that measured overall aesthetic outcome, volume, shape, symmetry, scarring, and nipple-areolar complex. The photographic assessments were made by five medical professionals who were shown photographs on a computer screen in a random order. Obtained data were stored in Excel and evaluated by Spearman's correlations using SPSS Statistics. Results We enrolled 92 women in this study, 10 did not respond to all scales of postoperative BREAST-Q, the remaining 82 women had undergone breast reconstruction. The correlation between BREAST-Q score and aesthetic score measured by Ten-Point Scale for the three BREAST-Q scales all show positive values in Spearman's correlation coefficient. Conclusion A significant correlation without any bias observed was found between the patient's satisfaction measured by BREAST-Q after breast reconstruction and the medical expert's aesthetic evaluation. [ABSTRACT FROM AUTHOR]

Application of fine-textured and Ca-rich fly ash may be helpful in enhancing soil carbon content via protecting soil organic C (SOC) by organo-mineral complexation and via reducing CO2 emission by carbonation (e.g. formation of CaCO3). However, very limited information is available on the effects of fly ash application on gases loss of C and soil C content. In this study, to estimate the potential use of fly ash as a soil amendment for SOC enhancement purposes, the effects of fly ash application (0, 5, and 10 w/w %) on microbial biomass C (MBC), CH4 and CO2 emissions, and on soil C content were investigated. A 60-days incubation experiment was conducted with an acidic soil in the presence of organic input (pig manure compost, PMC; hairy vetch, HV) with contrasting substrate quality under changing water regime from water-logged to unsaturated via a transition period. Fly ash application did not affect MBC under water-unsaturated conditions, but reduced (P < 0.01) microbial growth under water-logged conditions, probably due to the increased solubility of a certain toxic element such as arsenic under the anaerobic conditions. Across the 60 days of incubation, the CO2 emission was reduced by fly ash regardless of organic input by 20.5-41.3%; meanwhile, a decline of CH4 emission by fly ash application was significant (P < 0.05) only in the HV treatment. Overall, fly ash application slowed down gases C loss and increased soil C content, probably due to the retardation of CH4 and CO2 emission as well as the addition of C contained in the fly ash. Biochemical (inhibition of microbial activity), chemical (formation of CaCO3 via carbonation), and physical (restriction of gas diffusion) mechanisms were suggested for the fly ash effects. [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 effects of the liquid pig manure (LM) used in organic farming on the natural abundance of 15N and 13C signatures in plant tissues have not been studied. We hypothesized that application of LM will (1) increase δ15N of plant tissues due to the high δ15N of N in LM as compared with soil N or inorganic fertilizer N, and (2) increase δ13C of plant tissues as a result of high salt concentration in LM that decreases stomatal conductance of plants. To test these hypotheses, variations in the δ15N and δ13C of Chinese cabbage ( Brassica campestris L.) and chrysanthemum ( Chrysanthemum morifolium Ramatuelle) with two different LMs (with δ15N of +15.6 and +18.2‰) applied at two rates (323 and 646 kg N ha-1 for cabbage and 150 and 300 kg N ha-1 for chrysanthemum), or urea (δ15N = -2.7‰) applied at the lower rate above for the respective species, in addition to the control (no N input) were investigated through a 60-day pot experiment. Application of LM significantly increased plant tissue δ15N (range +9.4 to +14.9‰) over the urea (+3.2 to +3.3‰) or control (+6.8 to 7.7‰) treatments regardless of plant species, strongly reflecting the δ15N of the N source. Plant tissue δ13C were not affected by the treatments for cabbage (range −30.8 to −30.2‰) or chrysanthemum (−27.3 to −26.8‰). However, cabbage dry matter production decreased while its δ13C increased with increasing rate of LM application or increasing soil salinity ( P < 0.05), suggesting that salinity stress caused by high rate of LM application likely decreased stomatal conductance and limited growth of cabbage. Our study expanded the use of the δ15N technique in N source (organic vs. synthetic fertilizer) identification and suggested that plant tissue δ13C maybe a sensitive indicator of plant response to salinity stress caused by high LM application rates. [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]

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]

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]

Background: Despite the excellent contribution of contrast-enhanced breast magnetic resonance imaging (MRI), there are variable false-negative cases on MRI. Purpose: To evaluate the false-negative findings of breast cancer on previous MRI. Material and Methods: Between 2012 and 2016, we collected 132 patients who underwent surgery for a second primary cancer and had both current and previous MRI at an interval of <3 years. We included 45 patients; we excluded 38 patients who could not find a second cancer in the previous MRI and 49 patients who had a second cancer near to the original cancer and within within the same quadrant. Compared with current MRI, we retrospectively assessed the second primary cancer on previous MRI according to BI-RADS and analyzed the reasons of misinterpretation. Results: Analysis of previous MRI revealed 26 (57.8%) masses (mean size 7.7±2.25 mm), 12 (26.7%) non-mass enhancements (mean size 14.7±4.76 mm), and 7 (15.5%) foci. At first reading, 24 (53.3%) were missed, 17 (37.8%) were assessed as BI-RADS category 2 or 3, and 4 (8.9%) were assessed as category 4. On current MRI, 39 (86.7%) lesions showed an increase in size and 22 (48.9%) showed a change in kinetics to wash-out pattern. Conclusion: On previous MRI, missed or misinterpreted cancers show variable findings of mass and non-mass enhancements with any types of kinetics. Careful application of BI-RADS is necessary as well as an appropriate biopsy. Any lesion that increases in size and changes in kinetics should not be underestimated. [ABSTRACT FROM AUTHOR]

Purpose: Our study investigated whether any sonographic findings could be useful for differentiating between small triple-negative breast cancer (TNBC) and fibroadenoma. Methods: This retrospective study was approved by our Institutional Review Board, which waived the requirement for patient consent. From January 2009 to December 2010, the sonographic features of 181 pathologically proven TNBC tumors and 172 fibroadenomas measuring less than or equal to 2 cm in the longest dimension were reviewed and analyzed according to the fifth edition of the Breast Imaging Reporting and Data System (BI-RADS) lexicon. Mean tumor roundness was also measured using in-house software. Results: The median longest lesion dimension was 16 mm (range, 13 to 18 mm) in TNBCs and 13 mm (range, 10 to 16 mm) in fibroadenomas. In comparison to fibroadenomas, small TNBC tumors presented with a higher incidence of irregular shapes (66.9%), noncircumscribed margins (91.7%), hypoechoic echotexture (59.1%), posterior acoustic enhancement (65.2%), and associated features (24.4%). Most TNBCs were classified as BI-RADS category 4 (65.2%) or 5 (28.2%). The mean tumor roundness of small TNBCs was greater than that of fibroadenomas (60%±12% vs. 53%±13%). Multivariate analysis showed that older patient age, irregular shape, nonparallel orientation, posterior acoustic enhancement, associated features, a BI-RADS final assessment category of 4 or 5, and greater tumor roundness were significant independent factors indicative of TNBCs. Conclusion: TNBC tumors tend to demonstrate more suspicious sonographic features and greater tumor roundness than fibroadenomas. These features may have the potential to help differentiate between small TNBCs and fibroadenomas. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of our study was to investigate the morphology and distribution of calcifications initially interpreted as benign or probably benign, but proven to be malignant by subsequent stereotactic biopsy, and to identify the reason for misinterpretation or underestimation at the initial diagnosis. Materials and Methods: Out of 567 women who underwent stereotactic biopsy for calcifications at our hospital between January 2012 and December 2014, 167 women were diagnosed with malignancy. Forty-six of these 167 women had previous mammography assessed as benign or probably benign which was changed to suspicious malignancy on follow-up mammography. Of these 46 women, three women with biopsy-proven benign calcifications at the site of subsequent cancer were excluded, and 43 patients were finally included. The calcifications (morphology, distribution, extent, associated findings) in the previous and follow-up mammography examinations were analyzed according to the Breast Imaging Reporting and Data System (BI-RADS) lexicon and assessment category. We classified the patients into two groups: 1) group A patients who were still retrospectively re-categorized as less than or equal to BI-RADS 3 and 2) group B patients who were re-categorized as equal to or higher than BI-RADS 4a and whose results should have prompted previous diagnostic assessment. Results: In the follow-up mammography examinations, change in calcification morphology (n = 27, 63%) was the most frequent cause of assessment change. The most frequent previous mammographic findings of malignant calcification were amorphous morphology (n = 26, 60%) and grouped distribution (n = 36, 84%). The most frequent calcification findings at reassessment were amorphous morphology (n = 4, 9%), fine pleomorphic calcification (n = 30, 70%), grouped distribution (n = 23, 53%), and segmental calcification (n = 12, 28%). There were 33 (77%) patients in group A, and 10 patients (23%) in group B. Conclusion: Amorphous morphology and grouped distribution were the most frequent mammographic findings of calcifications that were misinterpreted or underestimated by the initial radiologist and confirmed as malignancy at follow-up. [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]

Purpose: To assess the imaging and clinicopathologic outcomes of recurrent and second breast cancer after breast-conserving surgery for invasive ductal carcinomas detected on follow-up mammography and breast ultrasound (US). Materials and Methods: Seventy-six women with an ipsilateral breast tumor recurrence (IBTR) or regional lymph node recurrence and/or contralateral breast cancer (RLNR & CBC) after breast-conserving surgery were included in this study. The mammography and US images were analyzed and the clinicopathologic parameters were compared between the groups. Results: Thirty had an IBTR, and 46 had a RLNR & CBC. The IBTR group’s mammography and US images frequently revealed calcification and masses on the breast, respectively. The most frequent site of RLNR detected during follow-up mammography and breast US was the axilla. In univariate analysis, the tumors in the IBTR group were predominantly estrogen receptor (ER)-negative, HER-2 overexpression, and p53-positive. ER and HER-2 were shown by the multivariate analysis to be independent parameters associated for both types of recurrences. Conclusion: A mass or calcification is frequently present in IBTR and the axillary lymph node is the most frequent site of RLNR. ER and HER-2 status are major independent factors associated with recurrent and second breast cancer. [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 purpose of this study is to evaluate the use of second-look ultrasonography (US) for investigating additional suspicious lesions detected on preoperative staging magnetic resonance imaging (MRI) for breast cancer. Methods: Between September 2008 and August 2010, 1,970 breast MRIs were performed at our medical institution for the evaluation of breast cancer before surgery. Second-look US was recommended for 135 patients with 149 suspicious lesions, following the MRI interpretation, and 108 patients with 121 lesions were included in this study. The detection rate on second-look US, according to the lesion type, diameter, and histopathological outcome, was analyzed. Results: Of the 121 lesions considered in this study, 97 (80.2%) were diagnosed on MRI as masses and 24 (19.8%) as non-mass-like lesions; 105 lesions (86.8%) were correlated and 16 (13.2%) were not correlated with the findings of second-look US. Of the 105 correlated lesions, 29 (27.6%) were proven to be malignant and 76 (72.4%) were benign. Although a greater number of large malignant lesions were correlated on second-look US than small benign lesions, there was no statistkally significant difference according to lesion diameter or type, as seen on MRI or pathology. Conclusion: We have concluded that second-look US is a useful diagnostic tool for lesions incidentally detected on breast MRI, as in this study, it could identify 86.8% of the MRI-detected breast lesions. [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]

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]