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Mapping aboveground biomass and its prediction uncertainty using LiDAR and field data, accounting for tree-level allometric and LiDAR model errors

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Forest Ecosystems 2020年第3期7卷 562-578页

作者： Svetlana Saarela AndréWästlund Emma Holmström Alex Appiah Mensah Sören Holm mats nilsson Jonas Fridman Göran Ståhl Faculty of Forest Sciences Swedish University of Agricultural SciencesSLU Skogsmarksgränd 17UmeåSE-90183Sweden

Background: The increasing availability of remotely sensed data has recently challenged the traditional way of performing forest inventories, and induced an interest in model-based inference. Like traditional design-based inference, model-based inference allows for regional estimates of totals and means, but in addition for wall-to-wall mapping of forest characteristics. Recently Light Detection and Ranging(LiDAR)-based maps of forest attributes have been developed in many countries and been well received by users due to their accurate spatial representation of forest resources. However, the correspondence between such mapping and model-based inference is seldom appreciated. In this study we applied hierarchical model-based inference to produce aboveground biomass maps as well as maps of the corresponding prediction uncertainties with the same spatial resolution. Further, an estimator of mean biomass at regional level, and its uncertainty, was developed to demonstrate how mapping and regional level assessment can be combined within the framework of model-based ***: Through a new version of hierarchical model-based estimation, allowing models to be nonlinear, we accounted for uncertainties in both the individual tree-level biomass models and the models linking plot level biomass predictions with LiDAR metrics. In a 5005 km2 large study area in south-central Sweden the predicted aboveground biomass at the level of 18 m×18 m map units was found to range between 9 and 447 Mg·ha^-1. The corresponding root mean square errors ranged between 10 and 162 Mg·ha^-1. For the entire study region, the mean aboveground biomass was 55 Mg·ha^-1 and the corresponding relative root mean square error 8%. At this level 75%of the mean square error was due to the uncertainty associated with tree-level ***: Through the proposed method it is possible to link mapping and estimation within the framework of model-based inference. Uncertainties in both tree-level bio

关键词： Aboveground biomass assessment Forest mapping Gauss-Newton Regression Hierarchical Model-Based inference LiDAR maps National Forest Inventory Uncertainty estimation Uncertainty map

Lifestyle, Biological Risk Markers, Morbidity and Mortality in a Cohort of Men 33 - 42 Years Old at Baseline, after 24-Year Follow-Up of a Primary Health Care Intervention

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Open Journal of Preventive Medicine 2015年第3期5卷 92-102页

作者： Lars-Goran Persson Hans Lingfors mats nilsson Sigvard Molstad Health Care Centre of Habo and Unit for Research and Development in Primary Health Care FuturumJonkopingSweden Futurum County Council of Jonkoping JonkopingSweden Department of Clinical Sciences General PracticeLund UniversityMalmoSweden

Objective: To study changes in lifestyle and biological risk markers in a 24-year follow-up study, and occurrences of cardiovascular diseases (CVD), cancer and total mortality from official registers. Design: A 24-year follow-up survey and register study of a cohort of men 33 - 42 years old, examined with a health profile at baseline. With the health profile based on lifestyle, biological risk markers, self-rated mental stress and mental health, the men were separated in different risk groups. Setting: Primary health care center of Habo in Sweden. Subjects: All 757 men, 33 - 42 years old, and living in the community of Habo in Sweden in 1985. Main Outcome Measures: Lifestyle, biological risk markers, morbidity from CVD and cancer, and total mortality. Results: Smoking and physical activity decreased during follow-up time while alcohol consumption increased. Biological risk markers, except diastolic blood pressure, deteriorated significantly with age. Based on three- lifestyle groups, 16 % of the men had a more favorable lifestyle and 19% had a less favorable life-style at follow-up compared with baseline. The men, who had been classified as high-risk, based on the health profile at baseline, had a significantly higher incidence of CVD and cancer in the register study compared to men in a low-risk group. The baseline non-participant group had a significantly higher incidence of CVD and a higher mortality compared to the low-risk group. Conclusion: A health profile with a combination of lifestyle factors and biological risk markers can already at the age of 33 - 42 years predict incidence of CVD and cancer on group level among men after 24 years.

关键词： Lifestyle Primary Health Care Health Dialogue Primary Prevention

Correction to:Efficient DNA-assisted synthesis of trans-membrane gold nanowires

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Microsystems & Nanoengineering 2018年第1期4卷 298-299页

Figure 2 and the descriptive text in the Section“SEM characterization of synthesized nanowires”of the previously published version of this Article were *** authors would like to replace Fig.2 and section“SEM charac... 详细信息

关键词： nanowires Figure replace

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瑞典泥炭开采区的CH_4和CO_2通量

AMBIO－人类环境杂志 2000年第8期29卷 499-503,517页

作者： Ingvar Sundh mats nilsson Catharina Mikkel Gunnar Granberg Bo Svensson 陶波王绍强瑞典农业科学大学微生物学系的助理教授瑞典农业科学大学获得林业生态学博士学位森林生态学博士学位土壤学博士学位微生物学博士学位

排水和泥炭开采可能引起泥炭地CH_4和CO_2等温室气体向大气中的排放量发生相当大的变化。在本研究中,我们采用密闭箱方法(closed chamber)测量了瑞典6个正在开采的泥炭地的CH_4和CO_2通量。结果显示,在沟渠测得的CH_4通量要比矿区条地(s... 详细信息

排水和泥炭开采可能引起泥炭地CH_4和CO_2等温室气体向大气中的排放量发生相当大的变化。在本研究中,我们采用密闭箱方法(closed chamber)测量了瑞典6个正在开采的泥炭地的CH_4和CO_2通量。结果显示,在沟渠测得的CH_4通量要比矿区条地(strips)高得多,例如,大部分泥炭地的CH_4排放量来自于沟渠。在生长季期间,这些泥炭地的CH_4排放总量(0.41～4.5g/m^2·a)与处于原始状态的泥炭地的情况相似。通过清除沟渠植被,可以使其CH_4的排放量保持较低水平。与CH_4的情况相似,在大多数泥炭地,矿区条地和沟渠都向大气中排放CO_2。在生长季节的排放量(0.23～1.0kg CO_2/m^2·a)主要是由矿区条地造成的。与采矿期间总的泥炭产量相比较而言,这些CO_2排放速率意味着:平均来说,泥炭地约6%的碳流失是由沼泽中微生物分解造成的。

关键词：瑞典泥炭开采区甲烷二氧化碳通量温室气体

运用卫星数据和来自国家森林清查的野外数据进行全国森林变量估计

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AMBIO－人类环境杂志 2003年第8期32卷 539-545页

作者： Heather Reese mats nilsson Tina Granqvist Pahlén Olle Hagner Steve Joyce Ulf Tingelf Mikael Egberth Hkan Olsson 王胜美国威斯康星-麦迪逊大学瑞典于默奥瑞典农业科学大学哥特兰岛地区林业局瑞典于默奥SLU遥感实验室加拿大沃特卢大学

瑞典约有55%的土地面积被森林所覆盖。目前,瑞典的森林覆盖没有统一的和地理学上明晰的描述。现存的独立性数据源是Landsat TM和SPOT HRV卫星数据、地图蒙片(map mask)和森林清查样地。它们在一起,使森林变量(如材积和林分年龄)的计算... 详细信息

瑞典约有55%的土地面积被森林所覆盖。目前,瑞典的森林覆盖没有统一的和地理学上明晰的描述。现存的独立性数据源是Landsat TM和SPOT HRV卫星数据、地图蒙片(map mask)和森林清查样地。它们在一起,使森林变量(如材积和林分年龄)的计算机估计成为可能。这些估计的精确度在像素水平上是低的,但在林分水平上较高。在规划木材资源应如何加以利用或出于监测目的时,这类基于栅格的森林数据对政府来说是有帮助的。本文描述了以有效成本建立森林变量估计全国数据库的生成流程。我们在林分水平上评价了瑞典西南部某地森林变量估计的精确度。结果表明,总材积估计的整体均方根误差为33%,年龄估计的整体均方根误差为23%。

关键词：森林林分覆盖样地材积清查土地面积中国国家瑞典

Catquest-9SF functioning over a decade–a study from the Swedish National Cataract Register

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Eye and Vision 2020年第1期7卷 553-562页

作者： mats Lundström Maria Kugelberg Per Montan Ingela nilsson Madeleine Zetterberg Konrad Pesudovs Anders Behndig Department of Clinical Sciences/Ophthalmology Faculty of MedicineLund UniversityTrossögatan 437137 KarlskronaLundSweden Department of Clinical Neuroscience Division of Ophthalmology and VisionKarolinska InstitutetStockholmSweden St Erik Eye Hospital StockholmSweden Capio Medocular LundSweden Department of Clinical Neuroscience Institute of Neuroscience and PhysiologySahlgrenska Academy at the University of GothenburgGothenburgSweden University of New South Wales AdelaideSAAustralia Department of Clinical Sciences/Ophthalmology UmeåUniversityUmeåSweden

Background:The Swedish National Cataract Register(NCR)collects data on cataract surgery outcomes during March,including patient-reported outcomes using the Catquest-9SF questionnaire for over 11 *** studies from NCR have shown that the preoperative visual acuity has improved over *** main purpose of this study was to evaluate the Catquest-9SF Rasch scoring performance in this changing environment.A second purpose was to describe clinical data over the same period for those who completed the ***:The performance of the Catquest-9SF was analysed by a separate Rasch analysis for each year,resulting in a preoperative and postoperative score for each participating patient in the annual *** clinical data and questionnaire scoring were analysed for each year in the period 2008-2018 ***:Data were available for 42,023 eyes for 11 annual cohorts(2008-2018).The psychometric properties of the questionnaire were stable during the study *** separation(precision)for the whole period was 2.58 and varied between 2.45 and *** person reliability was 0.87 and varied between 0.86 and *** targeting of question difficulty to person ability became less accurate over time meaning that the item activities became easier to carry out without *** average targeting for the whole period was−2.06 and changed from−1.92 in 2008 to−2.31 in *** person score improved both before surgery and after surgery,indicating that patients are undergoing surgery at a more able level and getting better *** average improvement by surgery decreased from 3.41 logits in 2008 to 3.21 logits in 2018(p=0.003).Over time,patient age decreased from 75 to 74 years(p<0.001)and the proportion of women decreased from 63.9 to 57.9%(p<0.001).The mean preoperative visual acuity in both the operated eye and the better eye improved over time(0.47 to 0.40 logMAR,p<0.001 and 0.22 to 0.19 logMAR,p<0.001,respectively),as did the mean post

关键词： Cataract extraction Outcomes Questionnaire Patient-reported outcomes Rasch analysis

predictors for failure of stent treatment for benign esophageal perforations- a single center 10-year experience

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World Journal of Gastroenterology 2014年第30期20卷 10613-10619页

作者： Saga Persson Peter Elbe Ioannis Rouvelas mats Lindblad Koshi Kumagai Lars Lundell Magnus nilsson Jon A Tsai Division of Surgery Karolinska Institutet and GastroCentrumDepartment of Clinical SciencesIntervention and TechnologyKarolinska University Hospital Huddinge141 86 StockholmSweden

AIM: To investigate possible predictors for failed self-expandable metallic stent (SEMS) therapy in consecutive patients with benign esophageal perforation-rupture (EPR).

关键词： Esophageal perforation Stents Esophagectomy Morbidity Mortality Mediastinitis

Extent of lymphadenectomy has no impact on postoperative complications after gastric cancer surgery in Sweden

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Chinese Journal of Cancer Research 2017年第4期29卷 313-322页

作者： chih-han kung huan song weimin ye magnus nilsson jan johansson ioannis rouvelas tomoyuki irino lars lundell jon a tsai mats lindblad Department of Surgery Skane University Hospital and Lund University Faculty of Medicine Department of Clinical Sciences 221 00 Lund Sweden

Objective： Curative gastric cancer surgery entails removal of the primary tumor with adequate margins including regional lymph nodes. European randomized controlled trials with recruitment in the 1990＇s reported increased morbidity and mortality for D2 compared to D 1. Here, we examined the extent of lymphadenectomy during gastric cancer surgery and the associated risk for postoperative complications and mortality using the strengths of a population-based study. Methods： A prospective nationwide study conducted within the National Register of Esophageal and Gastric Cancer. All patients in Sweden from 2006 to 2013 who underwent gastric cancer resections with curative intent were included. Patients were categorized into DO, D I, or D I ＋/D2, and analyzed regarding postoperative morbidity and mortality using multivariable logistic regression. Results： In total, 349 （31.7%） patients had a DO, 494 （44.9%） DI, and 258 （23.4%） DI＋/D2 lymphadenectomy. The 30-d postoperative complication rates were 25.5%, 25.1% and 32.2 % （DO, D I and D1 ＋/D2, respectively）, and 90-d mortality rates were 8.3%, 4.3 % and 5.8%. After adjustment for confounders, in mukivariable analysis, there were no significant differences in risk for postoperative complications between the lymphadenectomy groups. For 90-d mortality, there was a lower risk for D1 vs. DO. Conclusions： The majority of gastric cancer resections in Sweden have included only a limited lymphadenectomy （DO and DI）. More extensive lymphadenectomy （DI＋/D2） seemed to have no impact on postoperative morbidity or mortality.

关键词： Gastric cancer lymphadenectomy national database mortality complications

Consequences of Insufficient Selectivity in Quantitative and Qualitative Chemical Analysis

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Journal of Analytical Sciences, Methods and Instrumentation 2023年第2期13卷 13-25页

作者： mats Larsson Göran nilsson Department of Physics Alba Nova University Center Stockholm University Stockholm Sweden

A problem in chemical analysis in connection with measurements of a substance normally occurring in a sample, or identification of a substance which should not exist in a sample, is insufficient selectivity. In this article, we analyze this problem and propose remedies. We use a real doping case to illustrate how chemical noise causes a serious selectivity problem, probably causing a false positive outcome.

关键词： Chemical Analysis Quantitative and Qualitative Selectivity Chemical Measurement Procedures Measurement Errors Chemical Noise