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Global and Regional Surface nitrogen Balances in.intensive Agricultural Production Systems for the Period 1970-2030

Pedosphere 2005年第2期15卷 137-155页

作者： A. F. BOUwMAn G.Van DRECHT K. w. Van der HOEK netherlands Environmental Assessment Agency Netherlands Environmental Assessment AgencyLaboratory for Environmental Monitoring National Institute for Public Health and the EnvironmentP .O. Box 13720 BA Bilthoven (The Netherlands)National Institute for Public Health and the EnvironmentP .O. Box 13720 BA Bilthoven (The Netherlands)National Institute for Public Health and the EnvironmentP. O. Box 13720 BA Bilthoven (The Netherlands)

Global nitrogen (n) budgets for intensive agricultural systems were compiled for a 0.5 by 0.5 degree resolution. These budgets include n.inputs (n fertilizer, animal manure, biological n fixation and atmospheric n deposition) and outputs (n removal from the field in harvested crops and grass and grass consumption by grazing animals, ammonia volatilization,denitrification and leaching). Data for the historical years 1970 and 1995 and a projection for 2030 were used to study changes in the recovery of n and the different loss terms for intensive agricultural systems. The results indicate that the overall system n recovery and fertilizer use efficiency slowly increased in the industrialized countries between 1970 and 1995, the values for developing countries have decreased in the same period. For the coming three decades our results indicate a rapid increase in both the industrialized and developing countries. High values of ＞ 80% for fertilizer use efficiency may be related to surface n balance deficits, implying a depletion of soil n and loss of soil fertility. The projected intensification.in most developing countries will cause a gradual shift from deficits to surpluses in the coming *** projected fast growth of crop and livestock production, and intensification and associated increase in fertilizer inputs will cause a major increase in the surface n balance surplus in the coming three decades. This implies increasing losses of n compounds to air (ammonia, nitrous oxide and nitric oxide), and groundwater and surface water (nitrate).

关键词： animal manure fertilizer intensive agriculture nitrogen surface balance

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Efficient DnA-assisted synthesis of trans-membrane gold nanowires

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Microsystems & nanoen.ineering 2018年第1期4卷 490-497页

作者： Maoxiang Guo Iván Hernández-neuta narayanan Madaboosi Mats nilsson wouter van der wijngaart Department of Micro and nanosystems KTH Royal Institute of TechnologyOsquldas väg 10Stockholm 10044Sweden Science for Life Laboratory Department of Biochemistry and BiophysicsStockholm UniversityTomtebodavägen 23 ASolna SE-17165Sweden

whereas electric circuits and surface-based(bio)chemical sensors are mostly constructed in-plane due to ease of manufacturing,3D microscale and nanoscale structures allow denser integration of electronic components and improved mass transport of the analyte to(bio)chemical sensor *** work reports the first out-of-plane metallic nanowire formation based on stretching of DnA through a porous *** use rolling circle amplification(RCA)to generate long single-stranded DnA concatemers with one end anchored to the *** DnA strands are stretched through the pores in the membrane during liquid removal by forced *** the liquid–air interface movement across the membrane occurs in every pore,DnA stretching across the membrane is highly *** stretched DnA molecules are transformed into trans-membrane gold nanowires through gold nanoparticle hybridization and gold enhancement chemistry.A 50 fM oligonucleotide concentration,a value two orders of magnitude lower than previously reported for flat surface-based nanowire formation,was sufficient for nanowire *** observed nanowires in up to 2.7% of the membrane pores,leading to an across-membrane electrical conductivity reduction from open circuit to nal-to-noise ratio and can also be extended for use as a biosensor due to the high specificity and scope for multiplexing offered by RCA.

关键词： DnA stretching DnA detection gold nanowires nanowire synthesis membrane

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Current surgical treatment of diverticular disease in the netherlands

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world Journal of Gastroenterology 2010年第14期16卷 1742-1746页

作者： Annelien n Morks Bastiaan R Klarenbeek Elvira R Flikweert Donald L van der Peet Thomas M Karsten Eric H Eddes Miguel A Cuesta Peter w de Graaf Department of Surgery Reinier de Graaf Gasthuis PO Box 5011 2600 GA Delft The Netherlands Department of Surgery VU University Medical Center PO Box 7057 1007 MB Amsterdam The Netherlands Department of Surgery Deventer Ziekenhuis PO Box 5001 7400 GC Deventer The Netherlands

AIM: To evaluate the development of diagnostic tools, indications for surgery and treatment modalities concerning diverticular disease (DD) in the netherlands. METHODS: Data were collected from 100 patients who underwent surgery for DD in three Dutch hospitals. All hospitals used the same standardized data base. The collected data included patient demographics, patient history, type of surgery and complications. Patients were divided into two groups, one undergoing elective surgery (elective group) and the other undergoing acute surgery (acute group). RESULTS: Two hundred and ninety-nine patients were admitted between 2000 and 2007. One hundred and seventy-eight patients underwent acute surgery and 121 patients received elective operations. The median age of the 121 patients was 69 years (range: 28-94 years), significantly higher in acute patients (P = 0.010). Laparoscopic resection was performed in 31% of elective patients. In the acute setting, 61% underwent a Hartmann procedure. The overall morbidity and mortality were 51% and 10%, and 60% and 16% in the acute group, which were significantly higher than.in the elective group (36% and 1%). Only 35% of the temporary ostomies were restored. COnCLUSIOn: This study gives a picture of current surgical practice for DD in the netherlands. new developments are implemented in daily practice, resulting in acceptable morbidity and mortality rates.

关键词： Diverticulitis Surgery Diverticular disease

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Artificial intelligence for characterization of diminutive colorectal polyps:A feasibility study comparing two computer-aided diagnosis systems

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Artificial Intelligence in Gastrointestinal Endoscopy 2024年第1期5卷 11-22页

作者： Quirine Eunice wennie van der Zander Ramon M Schreuder Ayla Thijssen Carolus H J Kusters nikoo Dehghani Thom Scheeve Bjorn winkens Mirjam C M van der Ende-van Loon Peter H n de with Fons van der Sommen Ad A M Masclee Erik J Schoon Department of Gastroenterology and Hepatology Maastricht University Medical CenterMaastricht 6202 AZNetherlands GROw School for Oncology and ReproductionMaastricht UniversityMaastricht 6200 MDNetherlands Division of Gastroenterology and Hepatology Catharina Hospital EindhovenEindhoven 5602 ZANetherlands Department of Electrical En.ineering Eindhoven University of TechnologyEindhoven 5600 MBNetherlands Department of Methodology and Statistics Maastricht UniversityPostbus 6166200 MD MaastrichtNetherlands School for Public Health and Primary Care Maastricht UniversityMaastricht 6200 MDNetherlands

BACKGROUnD Artificial intelligence(AI)has potential in the optical diagnosis of colorectal *** To evaluate the feasibility of the real-time use of the computer-aided diagnosis system(CADx)AI for ColoRectal Polyps(AI4CRP)for the optical diagnosis of diminutive colorectal polyps and to compare the performance with CAD EYE^(TM)(Fujifilm,Tokyo,Japan).CADx influence on the optical diagnosis of an expert endoscopist was also *** AI4CRP was developed in-house and CAD EYE was proprietary software provided by *** CADxsystems exploit convolutional neural *** polyps were characterized as benign or premalignant and histopathology was used as gold ***4CRP provided an objective assessment of its characterization by presen.ing a calibrated confidence characterization value(range 0.0-1.0).A predefined cut-off value of 0.6 was set with valuesndicating benign and values≥0.6 indicating premalignant colorectal *** confidence characterizations were defined as values 40%around the cut-off value of 0.6(nd>0.76).Self-critical AI4CRP’s diagnostic performances excluded low confidence *** AI4CRP use was feasible and performed on 30 patients with 51 colorectal ***-critical AI4CRP,excluding 14 low confidence characterizations[27.5%(14/51)],had a diagnostic accuracy of 89.2%,sensitivity of 89.7%,and specificity of 87.5%,which was higher compared to *** EYE had a 83.7%diagnostic accuracy,74.2%sensitivity,and 100.0%*** performances of the endoscopist alone(before AI)increased nonsignificantly after reviewing the CADx characterizations of both AI4CRP and CAD EYE(AI-assisted endoscopist).Diagnostic performances of the AI-assisted endoscopist were higher compared to both CADx-systems,except for specificity for which CAD EYE performed *** Real-time use of AI4CRP was *** confidence values provided by a CADx is novel and self-critical AI4CRP sho

关键词： Artificial intelligence Colorectal polyp characterization Computer aided diagnosis Diminutive colorectal polyps Optical diagnosis Self-critical artificial intelligence

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Landslide Loss and Damage in Sindhupalchok District, nepal:Comparing Income Groups with Implications for Compensation and Relief

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International Journal of Disaster Risk Science 2018年第2期9卷 157-166页

作者： Kees van der Geest United nations University Institute for Environment and Human Security

The 2014 Jure landslide in Sindhupalchok District, nepal, caused significant loss and damage to ecosystems and livelihoods in the area. In the direct aftermath of the landslide, several disaster loss assessments were conducted, with the aim of coun.ing casualties,injured people, and damaged houses and *** useful and necessary in their own right, such rapid assessments do not reveal the true extent and significance of the losses and damages that people in disaster areas face, including their monetary value. we address this gap, based on a comprehensive household survey(n = 234), as well as other, qualitative research tools. Our results highlight the importance of differentiating between loss and damage in absolute monetary terms as opposed to losses relative to annual income. we find a stark contrast between the high absolute losses incurred by nonpoor households, and the high relative losses—up to 14 times their annual income—experienced by poor *** results have important implications for policy that addresses loss and damage, not only of landslides but also of other disasters. Loss and damage assessments need to take the livelihood characteristics of affected households into account to identify and support those most in need of compensation and relief.

关键词： Compensation and relief Impact assessment Landslides Loss and damage analysis nepal

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Laguerre calculus and Paneitz operator on the Heisenberg group

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Science China Mathematics 2009年第12期52卷 2549-2569页

作者： CHAnG der-Chen Department of Mathematics Georgetown University

Laguerre calculus is a powerful tool for harmonic analysis on the Heisenberg group. Many sub-elliptic partial differential operators can be inverted by Laguerre calculus. In this article, we use Laguerre calculus to find explicit kernels of the fundamental solution for the Paneitz operator and its heat equation. The Paneitz operator which plays an important role in CR geometry can be written as follows: $$ {\mathcal{P}_\alpha} = {\mathcal{L}_\alpha} \bar {\mathcal{L}_\alpha} = \fracn n\left[ {\sum\limits_{j = 1}^n {\left( {Z_j \bar Z_j + \bar Z_j Z_j } \right)} } \right]^2 + \alpha ^2 T^2 $$ Here “Z j ” j=1 n is an orthonormal basis for the subbundle T (1,0) of the complex tangent bundle T ?(H n ) and T is the “missing direction”. The operator $ \mathcal{L}_\alpha $ is the sub-Laplacian on the Heisenberg group which is sub-elliptic if α does not belong to an exceptional set Λ α . we also construct projection operators and relative fundamental solution for the operator $ \mathcal{L}_\alpha $ while α ∈ Λ α .

关键词： Paneitz operator Heisenberg group Laguerre calculus fundamental solution heat kernel spectrum 35H20 53C44

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Laguerre expansion on the Heisenberg group and Fourier-Bessel transform on C^n Dedicated to Professor Sheng GOnG on the occasion of his 75th birthday

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Science China Mathematics 2006年第11期49卷 1722-1739页

作者： CHAnG der-Chen GRIEnER Peter Department of Mathematics Georgetown University Washington DC 20057USA Department of Mathematics University of Toronto TorontoON M5S 3G3Canada

Given a principal value convolution on the Heisenberg group Hn = Cn × R, we study the relation between its Laguerre expansion and the Fourier-Bessel expansion of its limit on Cn. we also calculate the Dirichlet kerne... 详细信息

关键词： Heisenberg group, Fourier transform, Laguerre expansion, Bessel functions,Poisson sum, Dirichlet kernel.

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A note on Hermite and Subelliptic Operators

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Acta Mathematica Sinica,English Series 2005年第4期21卷 803-818页

作者： der Chen CHAnG Jing Zhi TIE Department of Mathematics Georgetown University Washington DC 20057-1233. USA Department of Mathematics University of Georgia Athens GA 30602-7403 USA

In this note, we compute the fundamental solution for the Hermite operator with singularity at an arbitrary point y∈R^n. we also apply this result to obtain the fundamental solutions for the Grushin operator in R^2 a... 详细信息

关键词： Hermite operator Heisenberg group Sub-Laplacian Gruhsin operator Heat kernel Laguerre function

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Fourier transform of anisotropic mixed-norm Hardy spaces

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Frontiers of Mathematics in China 2021年第1期16卷 119-139页

作者： Long HUAnG der-Chen CHAnG Dachun YAnG Laboratory of Mathematics and Complex Systems(Ministry of Education of China) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875China Department of Mathematics and Statistics Georgetown UniversityWashingtonDC 20057USA Graduate Institute of Business Adminstration College of ManagementFu Jen Catholic UniversityNew Teipei City 242China

Let a:=(a1,…,an)∈[1,∞)n,p:=(p1,…,pn)∈(0,1]n,Hpa(R^(n))be the anisotropic mixed-norm Hardy space associated with adefined via the radial maximal function,and let f belong to the Hardy space Hpa(R^(n)).In this article,we show that the Fourier transform fcoincides with a con.inuous function g onℝn.in the sense of tempered distributions and,moreover,this con.inuous function g,multiplied by a step function associated with a,can be pointwisely controlled by a constant multiple of the Hardy space norm of *** proofs are achieved via the known atomic characterization of Hpa(R^(n))and the establishment of two uniform estimates on anisotropic mixed-norm *** applications,we also conclude a higher order convergence of the con.inuous function gat the ***,a variant of the Hardy-Littlewood inequality in the anisotropic mixed-norm Hardy space setting is also *** these results are a natural generalization of the well-known correspon.ing conclusions of the classical Hardy spaces Hp(R^(n))with p∈0,1],and are even new for isotropic mixed-norm Hardy spaces on∈n.

关键词： Anisotropic(mixed-norm)Hardy space Fourier transform Hardy-Littlewood inequality

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Validation of the TOPAS Monte-Carlo Code of the Off-Field Dose of a 6 MV Synergy Linac

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Journal of Biosciences and Medicines 2024年第7期12卷 38-54页

作者： Kodjo Joel Fabrice n’Guessan Ibrahima Sakho Bogbé D. L. H. Gogon Department of Physics and Chemistry Faculty of Sciences and Technology Iba Der Thiam University of This This Senegal International Cancer Center of Dakar Dakar Senegal Department of Physics Faculty of Sciences and Technology Flix Houphouet Boigny University of Abidjan Abidjan Cte dIvoire

The risk of radiation.induced second cancer and the late tissue loss due to Off-field doses in radiotherapy remain a serious concern. Monte Carlo (MC) simulation is currently one of the most accurate methods for calculating these doses. MC simulation model based on the Particle Simulation Tool (TOPAS) has been developed to simulate the off-field dose of an Elekta Synergy linear accelerator (Linac) emitting 6 MV photons. Measurements were taken.in a water phantom using an ionization chamber to validate this model. The Percentage Depth Dose (PDD) at the depth of 0.0, 5.0, 10.0 and 15.0 cm from the beam axis for a 10 × 10 cm2 field size was measured and simulated. Off-field dose profiles at the depth of 1.5 (dmax), 5.0 and 10.0 cm for field sizes of 5 × 5, 10 × 10, 15 × 15, and 20 × 20 cm2 respectively were measured and simulated. Comparison of measured and simulated off-field dose values showed a good agreement. The average gamma passing rate of the PDDs and profiles curves for off-field doses were 87.5% and 98.11% respectively. The local dose difference based on the PDD curve between the measured and simulated was less than 6.0 % for all locations. For all field size considered in this study, the average difference between profile curves for off-field dose measured and simulated was 9.1%. PDDs and Profiles curves for off-field dose simulation uncertainties were less than 2.0% and 1.0% respectively. TOPAS-MC simulation model developed is a good representation of our 6 MV Linac Elekta Synergy for assessing off-field dose, which would be the primary cause of some secondary cancers.

关键词： Radiotherapy Off-Field Dose Secondary Cancer TOPAS-MC Simulation Dosimetry

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