Identifying crown areas in an undulating area planted with eucalyptus using unmanned aerial vehicle near-infrared imagery

In this letter, we propose an identification method of tree crown areas for imagery captured by a near-infrared camera on board an unmanned aerial vehicle platform over an undulating Eucalyptus planting area in Guangdong Province, China. The method extracts crown areas by applying mathematical morphology, unsupervised segmentation based on J-value segmentation, local spatial statistics, and Iterative Self-Organizing Data Analysis Technique Algorithm. Two morphology filters and four segmentation scales were compared between densely and sparsely planted plots as well as sunlit and shaded plots. The opening operation by the window size of 9×9 pixel and segmentation by the seed area sized 65×65 pixel achieved the best performance with overall accuracy of 91%, 93%, 89% and 91% in densely sunlit, sparsely sunlit, densely shaded and sparsely shaded plots.     

城市急救用血无人机配送系统的建设与初步应用

目的:探讨城市无人机血液配送系统建设的可行性和效果,为急救用血的配送提供新途径。方法:研究于2019年4月至2021年1月在杭州完成,主要参与单位为浙江大学医学院附属第二医院、浙江省血液中心和杭州迅蚁网络科技有限公司。首先构建城市急救用血无人机配送系统,研制无人机专用血液储存箱。利用无人机系统从浙江省血液中心运送血制品到浙大二院滨江院区,获取以下指标：(1)无人机送血的飞行时间;(2)血制品在运输过程中的实时温度;（3）利用百度地图软件测出道路交通的送血时间,并与无人机飞行时间进行比较。结果:城市无人机血液配送系统由智能物流无人机、低温血液储存箱、无人物流枢纽站、云端运行控制平台等部分组成。浙江省血液中心到浙大二院滨江院区的无人机航线距离（2.36±0.06）km,地面距离5.8 km,从2019年4月12日到2021年1月29日共飞行27架/次,飞行时间为（6.37±0.35）min,小于人工取血来回双程所需道路行驶时间（17.00±1.94）min。在一天的不同时间点,无人机送血可以节省15.98-4.28 min,平均节省（10.62±1.87）min。结论:城市无人机血液配送系统具有速度快、不受地面交通状况影响等优点,并能保证运输过程中血制品的安全,值得进一步的探索。     

城市急救用血无人机配送系统的建设与初步应用

目的:探讨城市无人机血液配送系统建设的可行性和效果,为急救用血的配送提供新途径。方法:研究于2019年4月至2021年1月在杭州完成,主要参与单位为浙江大学医学院附属第二医院、浙江省血液中心和杭州迅蚁网络科技有限公司。首先构建城市急救用血无人机配送系统,研制无人机专用血液储存箱。利用无人机系统从浙江省血液中心运送血制品到浙大二院滨江院区,获取以下指标：(1)无人机送血的飞行时间;(2)血制品在运输过程中的实时温度;（3）利用百度地图软件测出道路交通的送血时间,并与无人机飞行时间进行比较。结果:城市无人机血液配送系统由智能物流无人机、低温血液储存箱、无人物流枢纽站、云端运行控制平台等部分组成。浙江省血液中心到浙大二院滨江院区的无人机航线距离（2.36±0.06）km,地面距离5.8 km,从2019年4月12日到2021年1月29日共飞行27架/次,飞行时间为（6.37±0.35）min,小于人工取血来回双程所需道路行驶时间（17.00±1.94）min。在一天的不同时间点,无人机送血可以节省15.98-4.28 min,平均节省（10.62±1.87）min。结论:城市无人机血液配送系统具有速度快、不受地面交通状况影响等优点,并能保证运输过程中血制品的安全,值得进一步的探索。     

城市急救用血无人机配送系统的建设与初步应用

目的:探讨城市无人机血液配送系统建设的可行性和效果,为急救用血的配送提供新途径。方法:研究于2019年4月至2021年1月在杭州完成,主要参与单位为浙江大学医学院附属第二医院、浙江省血液中心和杭州迅蚁网络科技有限公司。首先构建城市急救用血无人机配送系统,研制无人机专用血液储存箱。利用无人机系统从浙江省血液中心运送血制品到浙大二院滨江院区,获取以下指标：(1)无人机送血的飞行时间;(2)血制品在运输过程中的实时温度;（3）利用百度地图软件测出道路交通的送血时间,并与无人机飞行时间进行比较。结果:城市无人机血液配送系统由智能物流无人机、低温血液储存箱、无人物流枢纽站、云端运行控制平台等部分组成。浙江省血液中心到浙大二院滨江院区的无人机航线距离（2.36±0.06）km,地面距离5.8 km,从2019年4月12日到2021年1月29日共飞行27架/次,飞行时间为（6.37±0.35）min,小于人工取血来回双程所需道路行驶时间（17.00±1.94）min。在一天的不同时间点,无人机送血可以节省15.98-4.28 min,平均节省（10.62±1.87）min。结论:城市无人机血液配送系统具有速度快、不受地面交通状况影响等优点,并能保证运输过程中血制品的安全,值得进一步的探索。     

Feasibility of using consumer-grade unmanned aerial vehicles to estimate leaf area index in Mangrove forest

As unmanned aerial vehicles (UAVs) become more popular, many studies investigate vegetation based on commercial UAV data. Although compared to satellite data, commercial UAV data can have flexible revisit frequencies, the possibility of using an even cheaper data source, consumer UAVs (red, green, and blue (RGB) only), to study vegetation remains unknown. The purpose of most frequent uses of consumer UAVs is recreation. This paper tests the feasibility of using consumer UAVs for mangrove research and proposed a method for mapping leaf area index (LAI) of mangrove. A commercial UAV image is also used for comparison. RGB-based vegetation indices like Excess Green Vegetation Index (ExG), Negative Excess Red Vegetation Index (NegExR), Green Leaf Index (GLI) and Normalized Green-red Difference Index (NGRDI) were used to build regression models against field measured LAI. The results showed that it was feasible to use consumer UAV data for mapping mangrove forest LAI, and the NegExR achieved the highest coefficient of determination (R²) in predicting LAI among all the indices. This paper showed that researchers who are neither familiar with aerial photogrammetry nor have access to commercial UAV data could perform high spatial resolution vegetation studies at a low cost.     

Detection of crevasses by geomorphometric treatment of data from unmanned aerial surveys

For Antarctic research, one of the important support tasks is a monitoring of sledge routes and other visited areas for detection of open crevasses and revealing of hidden, snow-covered ones. We study the possibility of revealing hidden crevasses with geomorphometric treatment of high-resolution, glacier digital elevation models (DEMs) produced from imagery captured by unmanned aerial systems (UASs). The study was conducted in East Antarctica, at a sledge route from the Progress to Vostok Stations. The survey performed with Geoscan 201 Geodesy UAS, resulted in a set of aerial images with a resolution of 6 cm. From these images, we produced glacier DEMs for a typical area with snow-covered crevasses. The glacier DEMs with the resolutions of 25 cm, 50 cm, and 1 m were treated by geomorphometric methods. We derived models of 16 morphometric variables including horizontal and vertical curvatures. For the 1-m gridded DEM, mapping of some variables allowed us to reveal one of the crevasses. The approach is functional, at least, for revealing crevasses with a width of 1.5 m and wider, covered by the snow layer with a thickness of up to 1.2 m.     

Registration of unmanned aircraft systems remote sensing imagery with severe outliers

We present an unmanned aircraft systems (UAS) image registration method to address the inherent severe outliers caused by low image overlap ratios and non-rigid distortions. The method comprises three components to maintain an accurate alignment on overlapping areas while taking advantage of outliers to approximate the non-overlapping areas. First, a penalty matrix is designed to be as the prior from the view of intensity and geometrical discrepancies. Second, a structure constraint is used to directly align the local structures of inliers, and simultaneously pull outliers coherently to reasonable locations. Third, a renewal scheme is designed to organically combine above to form a uniform feature point set registration process, and therein the dynamic SIFT threshold and outlier weight updating are implemented. Experiments on feature matching and image registration are performed using 150 pairs of UAS images and our method outperforms seven well-known methods in most cases.     

The accuracy of aerial triangulation products automatically generated from hyper-spatial resolution digital aerial photography

In recent years, unmanned airborne systems (UAS) have emerged as an important platform for collecting hyper-spatial resolution airborne remote sensing data. Using this hyper-spatial resolution imagery as input, modern aerial triangulation (AT) techniques, also known as structure-from-motion or SfM, can rapidly produce orthophotos and digital surface models (DSMs) at fine scales. Such data hold great promise for a number of applications, including routine and post-disaster assessment of transportation infrastructure, which provided the impetus for this research. Using hyper-spatial resolution (0.002 m) natural colour digital aerial photography acquired from a low-altitude UAS as input images, this research systematically investigated the horizontal and vertical accuracy of the AT generated orthophotos and DSMs, respectively. Hyper-spatial resolution aerial data were collected for a total of 28 study sites and, for each study site, coordinate information of 16 ground control points (GCPs) was collected using a survey grade real-time kinematic (RTK) Global Navigation Satellite System. Among the 16 GCPs for each site, 10 were used to calibrate the AT process while the remaining six GCPs were reserved to evaluate the horizontal and vertical accuracy of the orthophotos and DSMs. An average horizontal root mean squared error (RMSE) of 0.004 m and a vertical RMSE of 0.007 m across all sites indicate great promise for AT processed hyper-spatial resolution airborne remote sensing data to play a significant role in transportation infrastructure monitoring, particularly when considering the horizontal and vertical accuracy of the surveyed GCPs (0.004 and 0.006 m, respectively).     

Effects of proprioception training with exercise imagery on balance ability of stroke patients

[Purpose] The purpose of the present study was to examine and compare the effects of proprioceptive training accompanied by motor imagery training and general proprioceptive training on the balance of stroke patients. [Subjects and Methods] Thirty-six stroke patients were randomly assigned to either an experimental group of 18 patients or a control group of 18 patients. The experimental group was given motor imagery training for 5 minutes and proprioceptive training for 25 minutes, while the control group was given proprioceptive training for 30 minutes. Each session and training program was implemented 5 times a week for 8 weeks. The Korean version of the Berg Balance Scale (K-BBS), Timed Up and Go test (TUG), weight bearing ratio (AFA-50, Alfoots, Republic of Korea), and joint position sense error (Dualer IQ Inclinometer, JTECH Medical, USA) were measured. [Results] Both groups showed improvements in K-BBS, TUG, weight bearing ratio, and joint position sense error. The measures of the experimental group showed greater improvement than the control group. [Conclusion] Motor imagery training, which is not subject to time restrictions, is not very risky and can be used as an effective treatment method for improving the balance ability of stroke patients.Key words: Motor imagery, Proprioception, Stroke     

Exposure index in digital radiography: initial results of awareness and knowledge from Nigerian digital radiography practices

IntroductionExposure Index (EI) is incorporated into Digital Radiography (DR) systems to indicate incorrect exposure to enable matching exposure to the desired speed class of operation. However, knowledge of the utilization of EI by radiographers in a low-income country has not been investigated.MethodsA pre-tested questionnaire designed using Google forms, with open and close-ended questions was shared online with radiographers working with DR systems in public and private health facilities in some cities located in southern Nigeria. The 32-item questionnaire had two parts: Part A focused on socio-demographic characteristics and Part B focused on the respondents' awareness and knowledge of EI in DR systems. A 5-point Likert scale with 5 test items was used to assess the respondents' knowledge of EI. Statistical analyses were conducted using the Statistical Package for Social Sciences (SPSS) version 21.0. The probability value of p < 0.05 was considered statistically significant.ResultsAbout 8.3% of the respondents had good knowledge of EI in DR systems in spite of the awareness level of 24.7%. The absence of the EI concept in DR curriculum for undergraduates, the lack of EI software in DR systems, and equipment training by the vendor engineers were reasons for the low level of knowledge of EI in DR systems.ConclusionThere is low awareness and knowledge of EI by radiographers in this study, which suggests the need to maximize the benefits of EI concepts by ensuring its integration into clinical radiography practice and curriculum for undergraduates program, to improve knowledge, awareness, and practice in DR.     

Quantification of urinary oxalate with oxalate oxidase from beet stems

We describe an automated (ABA-100) enzymic method for determination of urinary oxalate by use of oxalate oxidase (EC 1.2.3.4) isolated from beet stems. The H2O2 produced by the oxidation of oxalate by oxalate oxidase is measured by coupling with oxidation and conjugation of 3-methyl-3-benzothiazolinone hydrazone with N,N-dimethylaniline with catalysis by horseradish peroxidase. The resulting indamine dye is measured spectrophotometrically by the difference in absorption at 500 and 600 nm. Interfering substances are removed by oxidation with acidic ferric chloride and by cation-exchange chromatography. The assay is sensitive to 5 mg of urinary oxalate per liter, the standard curve is linear to 70 mg/L, and the procedure requires less than 3 h for completion. The within-run CV was less than 1.6%, the between-day CV less than 5.6%. The oxalate oxidase method results in a mean and reference interval for oxalate excretion that are comparable with those by isotope dilution, gas-chromatographic, colorimetric, and other enzymic procedures.     

Quantification of hexanal as an index of lipid oxidation in human milk and association with antioxidant components

Hexanal, a secondary product of lipid oxidation, was identified as the major volatile aldehyde generated from lipid peroxidation in human milk. Hexanal was quantified in human milk using solid phase microextraction-gas chromatography/flame ionization detection that required correction for recovery based on the fat content of human milk. Alpha-tocopherol was the only tocopherol isomer in human milk found to be significantly correlated with hexanal (R = −0.374, p<0.05) and the total antioxidant capacity of human milk (ORAC_Fl (R = 0.408, p<0.01)). Ascorbic acid content was negatively correlated (R = −0.403, p<0.05) with hexanal, but not to ORAC_Fl in human milk. The effect of Holder pasteurization on oxidative status of human milk was determined using multiple parameters that included, hexanal level and malondialdehyde as markers of lipid oxidation, vitamins C and E content and antioxidant capacity (e.g. ORAC_Fl). Pasteurization did not affect the oxidative status of milk as measured by hexanal level, ORAC_Fl and malondialdehyde content. We conclude that hexanal is a sensitive and useful chemical indicator for assessing peroxidation reactions in human milk and that alpha tocopherol and ascorbic acid are two key antioxidant components in milk that contribute to protection against oxidation of milk lipids.     

Peripheral,visceral and body nitrogen balance of catabolic patients,without and with parenteral nutrition

The effect of major trauma and sepsis on skeletal muscle, central tissue and whole body nitrogen (N) metabolism was investigated in 5 patients before and during TPN (30 kcal, 0.30 g N kg^-1 day^-1). Fasting 3-methylhistidine (MEH) urinary excretion was elevated (407.9±67.6 mol m^-2 day^-1), muscle and body N balances (NB) were markedly negative (-28.2±4.6 g m^-2 day^-1 and-15.7±3.1 g m^-2 day^-1), while central tissue NB was positive (13.0±2.4 g m^-2 day^-1). TPN effected a reduction in MEH excretion (261.8±27.5 mmol m^-2 day^-1-p<0.05) and decreased the release of almost all amino acids from muscle tissue, some of them acting as catabolic markers. Muscle (-7.2±1.2 g m^-2 day^-1-p<0.01) as well as body NB (-4.8±1.4 g m^-2 day^-1-p<0.01) improved, whilst central tissue NB worsened, even though still positive (3.1±1.6 g m^-2 day^-1-p<0.05). Gathering fasting and TPN data MEH excretion was significantly related to both body (r=0.89) and muscle (r=0.73) NB, that were highly related to each other (r=0.93), being muscle always worse than body NB. In conclusion, the anticatabolic activity of TPN is confirmed, although our setting did not achieve muscle NB, it was consistently improved and seems to be the major determinant of body NB, in contrast central NB and central N utilization (46.4%±5.4 vs 15.8%±8.4-p<0.05) worsened.     

Quantification of flow volume with a new digital three-dimensional color Doppler flow approach: an in vitro study.

OBJECTIVE: The quantification of flow stroke volume is important for evaluation of patients with cardiac dysfunction and cardiovascular disease. Three-dimensional digital color Doppler flow imaging allows the acquisition of flow data in an orientation approximately parallel to flow and analysis of the Doppler flow velocities perpendicular to flow (cross-sectional flow calculation). This in vitro study assessed the applicability of this method for quantifying cardiac output in a funnel-shaped tube model similar to mitral inflow or the left ventricular outflow tract. METHODS: A new digital three-dimensional color Doppler method was used to acquire Doppler flow information. Raw scan line data with digital velocity assignments were obtained on a conventional Doppler color flow imaging system with a 180 degrees rotating multiplanar transesophageal probe connected to a computer workstation. Nine stroke volumes (20-60 mL) with flow rates ranging from 1.5 to 5.28 L/min in a funnel-shaped pulsatile laminar flow model were studied. Three-dimensional flow rates were compared with standard-of-reference measurements of flow obtained from timed collection in a graduated cylinder and with an ultrasonic flow meter. RESULTS: Within the funnel tube, the flow volumes that were calculated from the first, second, and third depths and the average of all 3 depths correlated well with the actual flow rate (r = 0.97-0.99). Results from the middle and second levels and from the average of all 3 depths provided the closest fit to the actual flow rates (r = 0.99; y = 0.96x + 0.14; and r = 0.98; y = 1.14x - 0.43, respectively). CONCLUSIONS: Although a work in progress, this digital three-dimensional color Doppler flow measurement method is feasible, accurate, and simple, and it may offer in vivo evaluation of blood volume flow given a favorable orientation between the valve orifice and the scanning device.     

Thymol derivatives with antibacterial and cytotoxic activity from the aerial parts of Ageratina adenophora

Three new thymol derivatives, 7-formyl-9-isobutyryloxy-8-hydroxythymol (1), 7,9-di-isobutyryloxy-8,10-dehydrothymol (2) and 2α-methoxyl-3β-methyl-6-methylol-2,3-dihydrobenzofuran (3), along with five known ones (4–8), were isolated from the aerial parts of the invasive plant Ageratina adenophora. Their structures were elucidated by extensive spectroscopic analysis and they were all isolated from the aerial part of A. adenophora for the first time. These compounds, except 8, selectively showed in vitro antimicrobial activity against three Gram-(+) and two Gram-(−) bacterial strains. In particular, compounds 1 and 5 showed notable in vitro antimicrobial activity against all five bacterial strains with IC₅₀ values ranging from 3.9 to 15.6 μg mL⁻¹, as compared to reference compound kanamycin sulfate with a MIC value 1.9–3.9 μg mL⁻¹. Compounds 1 and 5 were further revealed to show in vitro cytotoxic activity against three tested human tumor (MCF-7, NCI-H460 and HeLa) cell lines, with IC₅₀ values ranging from 7.45 to 28.63 μM. Compounds 7 and 8 selectively showed slight but detectable in vitro cytotoxicity toward MCF-7 and NCI-H460 cell lines, with IC₅₀ values 44.65–83.19 μM. No cytotoxic effects were detected in the bioassay of the other four thymol derivatives. The present results provide new data to support that the aerial parts of A. adenophora are a rich source of bioactive chemicals valuable in medicinal applications.

Eight thymol derivatives including three new ones (1–3) were obtained from the aerial parts of Ageratina adenophora, with most of them, in particular 1 and 5, showing notable in vitro antimicrobial and cytotoxic activity.     

平衡功能训练在椎-基底动脉供血不足性眩晕治疗中的运用

目的探讨椎-基底动脉供血不足性眩晕的治疗方法。方法81例以“头昏”、“眩晕”为初始或主要表现的椎-基底动脉供血不足患者随机分为两组,试验组41例,对照组40例,两组患者人院时均作Hallpike试验,试验组患者在常规治疗同时配合平衡功能训练,对照组患者仅给予常规治疗。结果81例患者Hallpike试验阳性46例（阳性率为56．8％）;试验组显效率（36．6％）明显高于对照组（17．5％）,试验组无效率（14．6％）明显低于对照组（35．0％）。结论当椎-基底动脉供血不足的患者存在周围性平衡功能障碍时,平衡功能训练疗效显著。     

运动想象足背屈联合辅助站立平衡训练对脑卒中偏瘫早期病人下肢运动功能康复的影响

[目的]探讨运动想象足背屈联合辅助站立平衡训练对脑卒中偏瘫早期病人下肢运动功能康复的作用。[方法]选择脑卒中偏瘫早期病人60例,按入院顺序编号分为常规训练组和联合训练组,常规训练组给予常规康复治疗,联合训练组在常规康复治疗基础上增加运动想象足背屈和辅助站立平衡训练,连续训练6周;治疗前后分别采用简化Fugl-Meyer评分(FMA)下肢运动功能、足背屈肌群的徒手肌力检查评级(MMT)、Tinetti步态评估量表(TGA)和Berg平衡量表对病人下肢运动和平衡功能进行评定。[结果]治疗6周后联合训练组病人FMA下肢运动功能积分、TGA评分、Berg平衡量表评分均高于治疗前和常规训练组(P0.01)。[结论]采用运动想象足背屈联合早期辅助站立平衡训练可促进患侧下肢站立平衡和步行能力。