The main aim of this paper was to calibrate and evaluate the DeNitrification-DeComposition (DNDC) model for estimating N2O emissions and crop productivity for a summer maize-winter wheat double ...cropping system with different N fertilizer rates in Hebei, China. The model’s performance was assessed before and after calibration and model sensitivity was investigated. The calibrated and validated DNDC performed effectively in estimating cumulative N2O emissions (coefficient of determination (1:1 relationship; r2) = 0.91; relative deviation (RD) = −13 to 16%) and grain yields for both crops (r2 = 0.91; RD = −21 to 7%) from all fertilized treatments, but poorly estimated daily N2O patterns. Observed and simulated results showed that optimal N fertilizer treatment decreased cumulative N2O flux, compared to conventional N fertilizer, without a significant impact on grain yields of the summer maize-winter wheat double cropping system. The high sensitivity of the DNDC model to rainfall, soil organic carbon and temperature resulted in significant overestimation of N2O peaks during the warm wet season. The model also satisfactorily estimated daily patterns/average soil temperature (o C; 0–5 cm depth) (r2 = 0.88 to 0.89; root mean square error (RMSE) = 4 °C; normalized RMSE (nRMSE) = 25% and index of agreement (d) = 0.89–0.97) but under-predicted water filled pore space (WFPS; %; 0–20 cm depth) (r2 = 0.3 to 0.4) and soil ammonium and nitrate (exchangeable NH4+ & NO3−; kg N ha−1; r2 = 0.97). With reference to the control treatment (no N fertilizer), DNDC was weak in simulating both N2O emissions and crop productivity. To be further improved for use under pedo-climatic conditions of the summer maize-winter wheat double cropping system we suggest future studies to identify and resolve the existing problems with the DNDC, especially with the control treatment.
Crop sequence of the maize and wheat crops in the summer maize-winter wheat double cropping system. Display omitted
•Calibrated DNDC effectively estimated cumulative N2O flux and grain yields.•High sensitivity of DNDC to input parameters resulted in overestimation of N2O peaks.•DNDC was weak in simulating control treatment.•DNDC satisfactorily estimated soil temperature but under-predicted WFPS and soil N.•Optimal N fertilizer decreased N2O flux without a significant impact on grain yields.
The calibrated DNDC model effectively estimated cumulative N2O emissions, grain yields and soil temperature but underestimated WFPS and soil N, in a winter wheat-summer maize double cropping system.
Global warming is a challenge to animal health, because of increased heat stress, with subsequent induction of immunosuppression and increased susceptibility to disease. Toll-like receptors (TLR) are ...pattern recognition receptors that act as sentinels of pathogen invasion and tissue damage. Ligation of TLRs results in a signaling cascade and production of inflammatory cytokines, which eradicate pathogens and maintain the health of the host. We hypothesized that the TLR signaling pathway plays a role in immunosuppression in heat-stressed pigs. We explored the changes in the expression of TLR2, TLR4 and the concentration of acute inflammatory cytokines, such as IL-2, IL-8, IL-12 and IFN-γ in Bama miniature pigs subjected to 21 consecutive days of heat stress, both in vitro and in vivo models. The results showed that heat stress induced the upregulation of cortisol in the plasma of pigs (P<0.05); TLR4 mRNA was elevated, but IL-2 was reduced in peripheral blood mononuclear cells (PBMC, P<0.05). The white blood cell count and the percentage of granulocytes (eosinophilic+basophilic) decreased significantly in heat-stressed pigs (P<0.05). In the in vitro model (PBMC heat shocked for 1 h followed by a 9 h recovery period), TLR2 and TLR4 mRNA expression also increased, as did the concentration of IL-12 in supernatants. However, IFN-γ was significantly reduced in PBMC culture supernatants (P<0.05). We concluded that a consecutive heat stress period elevated the expression of TLR2 and TLR4 in PBMC and increased the plasma levels of inflammatory cytokines. These data indicate that TLR activation and dysregulation of cytokine expression in response to prolonged heat stress may be associated with immunosuppression and increased susceptibility to antigenic challenge in Bama miniature pigs.
The effects of nitrogen and straw management on global warming potential (GWP) and greenhouse gas intensity (GHGI) in a winter wheat–summer maize double-cropping system on the North China Plain were ...investigated. We measured nitrous oxide (N2O) emissions and studied net GWP (NGWP) and GHGI by calculating the net exchange of CO2 equivalent (CO2-eq) from greenhouse gas emissions, agricultural inputs and management practices, as well as changes in soil organic carbon (SOC), based on a long-term field experiment established in 2006. The field experiment includes six treatments with three fertilizer N levels (zero N (control), optimum and conventional N) and straw removal (i.e. N0, Nopt and Ncon) or return (i.e. SN0, SNopt and SNcon). Optimum N management (Nopt, SNopt) saved roughly half of the fertilizer N compared to conventional agricultural practice (Ncon, SNcon), with no significant effect on grain yields. Annual mean N2O emissions reached 3.90 kg N2O-N ha−1 in Ncon and SNcon, and N2O emissions were reduced by 46.9% by optimizing N management of Nopt and SNopt. Straw return increased annual mean N2O emissions by 27.9%. Annual SOC sequestration was 0.40–1.44 Mg C ha−1 yr−1 in plots with N application and/or straw return. Compared to the conventional N treatments the optimum N treatments reduced NGWP by 51%, comprising 25% from decreasing N2O emissions and 75% from reducing N fertilizer application rates. Straw return treatments reduced NGWP by 30% compared to no straw return because the GWP from increments of SOC offset the GWP from higher emissions of N2O, N fertilizer and fuel after straw return. The GHGI trends from the different nitrogen and straw management practices were similar to the NGWP. In conclusion, optimum N and straw return significantly reduced NGWP and GHGI and concomitantly achieved relatively high grain yields in this important winter wheat–summer maize double-cropping system.
Valproic acid is an anticonvulsant, which is also widely used for treating psychiatric disorders. Some clinical trials have demonstrated benefits of valproic acid augmentation therapy in ...schizophrenia. Interindividual variability in valproic acid dose and serum concentration may reflect functional consequences of genetic polymorphisms in genes encoding drug-metabolizing enzymes. The aim of this study was to determine the relationship between serum concentrations of valproic acid and single nucleotide polymorphisms of the cytochrome P450 (CYP) 2C19 gene in patients with schizophrenia. All patients had been receiving fixed dose of valproic acid for at least 2 weeks. The daily doses were 0.5-1.5 g. No other drugs except olanzapine were coadministered. Serum concentrations of valproic acid were measured using the ultra-high performance liquid chromatography method with mass-spectrometric detection. The CYP2C19 (CYP2C19*2 G681A rs4244285 and CYP2C19*3 G636A rs4986893) genotypes were identified by real-time PCR analyses. The mean concentration/dose ratios of valproic acid were significantly higher in patients with CYP2C19 *1/*2 genotype (P < 0.01) or CYP2C19 *2/*3 genotype (P < 0.01) than in those with CYP2C12 *1/*1 genotype. The mean concentration/dose ratios of valproic acid were significantly higher in patients with 1 (P < 0.01) or 2 (P < 0.01) mutated alleles for CYP2C19 than in those without mutated alleles. And the post hoc analysis revealed that the result has acceptable statistical (power (1 - β) = 0.8486 at type I level of 0.05) to support the observed significant associations for CYP2C19 SNPs and serum C/D ratios of valproic acid. The findings of this study suggest that the genetic polymorphisms of CYP2C19 significantly affect the steady-state serum concentrations of valproic acid in Chinese Han population. The determination of the CYP2C19 genotypes may be useful for dosing adjustment in schizophrenia patients on valproic acid therapy.
Objective
To update the oncological results and identify recurrent risk factors in young patients with early stage cervical cancers following abdominal radical trachelectomy (ART).
Design
...Retrospective study.
Setting
A university‐based cancer hospital.
Population
Three hundred and thirty‐three patients.
Methods
We conducted a retrospective analysis from a prospectively maintained database of patients undergoing ART from April 2004 to December 2017.
Main outcome measures
Survival rate, clinicopathological factors related to recurrences.
Results
Two hundred and seventy‐one patients had squamous carcinomas (SCC), 51 had pure adenocarcinomas (AC), and 11 had adenosquamous carcinomas (AS). One hundred thirty‐two women (39.6%) had tumours ≥2 cm. With a median follow up of 56 months (range, 6–169), 11 patients (3.3%) had recurrence, and five patients (1.5%) died. The cumulative 5‐year recurrence‐free survival and overall survival rates were 96.3 and 98.6%, respectively. The recurrence rate in women with tumours ≥2 cm was comparable to that in patients with tumours <2 cm (5.3 versus 2.0%, respectively, P = NS). However, the recurrence rate was significantly higher in patients with AS histology than those with AC and SCC histology (18.2, 3.9, and 2.6%, respectively, P < 0.05). All of the recurrent patients with AS histology had tumours ≥2 cm. Multivariate analysis showed that the only independent risk factor for recurrence was histology type.
Conclusions
This updated series showed a favourable survival rate following ART. These results further supported that ART was a safe option for well‐selected patients with stage IB1 cervical cancers ≥2 cm. However, if patients with tumours ≥2 cm have AS histology, they should be advised with great caution when contemplating ART.
Tweetable
Abdominal radical trachelectomy could be a safe, fertility‐sparing option for strictly selected patients with stage IA1–IB1 cervical cancers ≤4 cm.
Tweetable
Abdominal radical trachelectomy could be a safe, fertility‐sparing option for strictly selected patients with stage IA1–IB1 cervical cancers ≤4 cm.
In this work, we establish a goal-oriented space–time finite element method for a class of dissipative heterogeneous materials. Those materials are modeled on both micro- and macroscale, with a scale ...transition of volume averaging type satisfying the Hill–Mandel condition. A nonuniform transformation field analysis is performed on the microscopic inelastic strain fields for a model reduction. Reduced variables are deduced from a space–time decomposition of those inelastic strain fields. Closed-form constitutive relations are derived from some dissipative considerations, thus resulting into a reduced order homogenization problem. The resulting model error is sufficiently small for the considered class of materials, thus leaving the discretization error of the finite element method as a main error source. For ease of error estimate, we rewrite the reduced order problem in a multifield formulation. Based on duality techniques, a backward-in-time dual problem is derived from a Lagrange method, rendering error representations of a user-defined quantity of interest. Combining a patch recovery technique, a computable error estimator is developed to quantify both spatial and temporal discretization errors. By means of a localization technique, local error estimators are used to drive a greedy adaptive refinement algorithm in space and time. The effectiveness of the resulting algorithm is confirmed by several numerical examples w.r.t. a prototype model.
•A novel adaptive space–time finite element method for heterogeneous dissipative materials.•A multifield formulation for a class of reduced order twoscale plasticity problems that is convenient for an error estimation.•Goal-oriented error estimation for adaptive control of spatial and temporal discretization errors in combination with the nonuniform transformation field analysis.
The annual nitrogen (N) budget and groundwater nitrate-N concentrations were studied in the field in three major intensive cropping systems in Shandong province, north China. In the greenhouse ...vegetable systems the annual N inputs from fertilizers, manures and irrigation water were 1358, 1881 and 402
kg
N
ha
−1 on average, representing 2.5, 37.5 and 83.8 times the corresponding values in wheat (
Triticum aestivum L.)–maize (
Zea mays L.) rotations and 2.1, 10.4 and 68.2 times the values in apple (
Malus pumila Mill.) orchards. The N surplus values were 349, 3327 and 746
kg
N
ha
−1, with residual soil nitrate-N after harvest amounting to 221–275, 1173 and 613
kg
N
ha
−1 in the top 90
cm of the soil profile and 213–242, 1032 and 976
kg
N
ha
−1 at 90–180
cm depth in wheat–maize, greenhouse vegetable and orchard systems, respectively. Nitrate leaching was evident in all three cropping systems and the groundwater in shallow wells (<15
m depth) was heavily contaminated in the greenhouse vegetable production area, where total N inputs were much higher than crop requirements and the excessive fertilizer N inputs were only about 40% of total N inputs.
Intensive greenhouse vegetable production systems may pose a greater nitrogen pollution threat than apple orchards or cereal rotations to soil and water quality in north China.
The aim of this article was to quantify socioeconomic inequalities in dental caries experience among Australian children and to identify factors that explain area-level socioeconomic inequalities in ...children’s dental caries. We used data from the National Child Oral Health Survey conducted in Australia between 2012 and 2014 (n = 24,664). Absolute and relative indices of socioeconomic inequalities in the dental caries experience in primary and permanent dentition (decayed, missing, and filled surfaces dmfs and DMFS, respectively) were estimated. In the first stage, we conducted multilevel negative binomial regressions to test the association between area-level Index of Relative Socioeconomic Advantage and Disadvantage (IRSAD) and dental caries experience (dmfs for 5- to 8-y-olds and DMFS for 9- to 14-y-olds) after adjustment for water fluoridation status, sociodemographics, oral health behaviors, pattern of dental visits, and sugar consumption. In the second stage, we performed Blinder-Oaxaca and Neumark decomposition analyses to identify factors that explain most of the area-level socioeconomic inequalities in dental caries. Children had a mean dmfs of 3.14 and a mean DMFS of 0.98 surfaces. Children living in the most disadvantaged and intermediately disadvantaged areas had 1.96 (95% confidence interval, 1.69–2.27) and 1.45 (1.26–1.68) times higher mean dmfs and 1.53 (1.36–1.72) and 1.43 (1.27–1.60) times higher mean DMFS than those living in the most advantaged areas, respectively. Water fluoridation status (33.6%), sugar consumption (22.1%), parental educational level (14.2%), and dental visit patterns (12.7%) were the main factors explaining area-level socioeconomic inequalities in dental caries in permanent dentition. Among all the factors considered, the factors that contributed most in explaining inequalities in primary dental caries were dental visits (30.3%), sugar consumption (20.7%), household income (20.0%), and water fluoridation status (15.9%). The inverse area-level socioeconomic inequality in dental caries was mainly explained by modifiable risk factors, such as lack of fluoridated water, high sugar consumption, and an unfavorable pattern of dental visits.
The aim of this study was to determine the skeletal stability of Le Fort I maxillary advancement following the surgery-first approach, by three-dimensional (3D) assessment of cone beam computed ...tomography (CBCT) scans and digital dental models. CBCT scans of 25 class III patients obtained 1 week preoperatively (T0) and 1 week (T1) and 6 months (T2) postoperatively were superimposed to measure surgical movements (T0–T1) and skeletal relapse (T1–T2). The distorted dentition of the CBCT scans at T1 was replaced with 3D images of the dental models to assess the postoperative occlusion. Surgical movements of the maxilla (mean ± standard deviation values) were 6.79 ± 2.30 mm advancement, 1.28 ± 1.09 mm vertically, and 0.71 ± 0.79 mm mediolaterally. Horizontal rotation (yaw) was 1.56° ± 1.21°, vertical rotation (pitch) 1.86° ± 1.88°, and tilting (roll) 1.63° ± 1.54°. At T2, the posterior relapse was 0.72 ± 0.43 mm (P = 0.001) and relapse in pitch was 1.56° ± 1.42° (P = 0.007). There was no correlation between the size of the surgical movements and the amount of relapse. A weak correlation was noted between the number of teeth in occlusal contact immediately following surgery and relapse of maxillary roll (r = − 0.434, P = 0.030). The stability of maxillary advancement with the surgery-first approach was satisfactory and was not correlated with the quality of the immediate postoperative occlusion.
A new magnetorheological elastomer isolator in shear–compression mixed mode is designed in this article. Two pieces of magnetorheological elastomer fabricated with different dimensions are utilized ...in the isolator. One magnetorheological elastomer operates on shear mode, and the other operates on compression mode. Next, a finite element method magnetic package is used to analyze the designed magnetic circuit system, and a test system is established to obtain the frequency response of magnetorheological elastomer isolator with mixed mode. It is found that the natural frequency of magnetorheological elastomer isolator changes greatly with variable current applied, and the amplitude of vibration is attenuated widely. Compared with the natural frequency of 0 A, the increment of natural frequency is up to 103% with applied current reaches to 1.5 A. Finally, the dynamic model of isolator system is established, and the stiffness and damping coefficients of magnetorheological elastomer isolator are identified by the experimental method. Meanwhile, the variable range for stiffness and damping of magnetorheological elastomer isolator with mixed mode is greater than that of single mode, which has been proved in theory and experiments.
PDF
