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A comparison of animal color measurements using a commercially available digital color sensor and photograph analysis

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Current Zoology 2020年第6期66卷 601-606页

作者： Alex D.Potash daniel U.Greene Gabrielle A.Foursa Verity l.Mathis l.Mike Conner Robert A.McCleery Department of Wildlife Ecology and Conservation University of Florida Institute of Food and Agricultural ScienceGainesvilleFL 32611USA Weyerhaeuser Company Environmental Research SouthColumbusMS 39701USA Department of Biology University of FloridaGainesvilleFL 32611USA Florida Museum of Natural History University of FloridaGainesvilleFL 32611USA The Jones Center at Ichauway NewtonGA 39870USA

An animal's pelage,feather,or skin color can serve a variety of functions,so it is important to have multiple standardized methods for measuring *** of the most common and reliable methods for measuring animal coloration is the use of standardized digital photographs of *** tech no logy in the form of a commercially available handheld digital color sensor could provide an alter native to photography-based animal color *** determine whether a digital color sensor could be used to measure animal coloration,we tested the ability of a digital color sensor to measure coloration of mammalian,avian,and lepidopteran museums *** compared results from the sensor to measurements taken using traditional photography *** study yielded significant differences between photography-based and digital color sensor measurements of brightness(light to dark)and colors along the green to red *** was no difference between photographs and the digital color sensor measurements for colors along the blue to yellow *** average difference in recorded color(AE)by the 2 methods was above the threshold at which humans can perceive a *** were sign讦icant correlations between the sensor and photographs for all measurements indicating that the sensor is an effective animal coloration measuring ***,the sensor's small aperture and narrow light spectrum range designed for human-vision limit its value for ecological *** discuss the conditions in which a digital color sensor can be an effective tool for measuring animal coloration in both laboratory settings and in the field.

关键词： animal coloration color measurement comparative method digital photography museum specimens Nix color sensor

A limit equilibrium fracture zone model to investigate seismicity in coal mines

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International Journal of Mining Science and Technology 2018年第5期28卷 745-753页

作者： daniel Malan John Napier Department of Mining Engineering Faculty of Engineering Built Environment and IT University of Pretoria

This paper explores possible synergies between techniques used to minimise seismicity in deep South African gold mines and their applicability to control coal bumps. The paper gives a summary of the techniques used in the deep gold mines and a critical appraisal if these are useful in coal mines. The techniques typically include control of mining rate, preconditioning, optimisation of extraction sequences and centralised blasting. Of particular interest to the coal bump problem is an experimental limit equilibrium fracture zone model implemented in a displacement discontinuity code. This was recently developed for the gold mines to enable the interactive analysis of complex tabular mine layout extraction sequences. The model specifically accommodates energy dissipation computations in the developing fracture zone near the edges of these excavations. This allows the released energy to be used as a surrogate measure of ongoing seismic activity and addresses a number of the weaknesses in the traditional usage of this quantity as a criterion for the design of seismically active layouts. This paper investigates the application of the model to a hypothetical coal longwall layout and the specific problem of coal bumps.

关键词： Coal bumps limit equilibrium model Mining rate Seismicity

light-driven high-precision cell adhesion kinetics

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light(Science & Applications) 2022年第10期11卷 2256-2257页

作者： Zhiyuan Zhang daniel Ahmed Acoustic Robotics Systems laboratory Institute of Robotics and Intelligent SystemsDepartment of Mechanical and Process EngineeringETH ZurichS?umerstrasse 4CH-8803 ZurichSwitzerland

Existing single-cell adhesion kinetics methods are performed under conditions highly unlike the physiological cell adhesion ***,researchers have developed a new optical technique for high-precision measurement of cell... 详细信息

关键词： conditions. kinetics formed

Catalytic dechlorination and detoxification of 1-(2-chlorophenyl) ethanol by Pd/Fe

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第5期11卷 356-362页

作者： G. daniel SHENG College of Biological and Environmental Engineering Zhejiang University of Technology

1-(2-chlorophenyl) ethanol (CPE) is of health and environmental concern due to its toxicity and its use as an inter-mediate in pharmaceutical manufacturing. The current work deals with the catalytic reductive dechlorination and detoxification of CPE by Pd/Fe bimetal. CPE was effectively dechlorinated to 1-phenyl ethanol (PE) accompanied by the equivalent release of chloride. The extent of CPE dechlorination increased with temperature,Fe dosage and Pd loading. A decrease in solution pH increased CPE dechlorination,resulting presumably from an increase in hydrogen production. Under the specific conditions of 20 g/l Pd/Fe,0.10% Pd (w/w) and initial pH 5-6,the CPE dechlorination was completed within 145 min. The dechlorination fol-lowed a pseudo-first-order kinetics with an activation energy of 56.7 kJ/mol. The results of toxicity testing showed that CPE was very toxic to Chlorella,whereas PE showed little toxicity. The toxicity of the reaction solution declined gradually and the pro-moting effects on Chlorella intensified consequently with the dechlorination process. Thus,the reductive dechlorination of CPE to PE by Pd/Fe was a detoxification process. It may be used to effectively reduce the toxicological effects of CPE-contaminated wastewater,thereby enhancing the performance of subsequent biological processes in wastewater treatment.

关键词： 1-(2-chlorophenyl) ethanol (CPE) Pd/Fe Catalytic reductive dechlorination Detoxification 1-phenyl ethanol (PE)

Three-dimensional light structure of an upland Quercus stand post-tornado disturbance

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Journal of Forestry Research 2020年第1期31卷 141-153页

作者： Kevin G.Willson lauren E.Cox Justin l.Hart daniel C.Dey Department of Geography University of AlabamaTuscaloosaAL 35487USA Department of Environmental Science Policyand ManagementUniversity of CaliforniaBerkeleyCA 94720USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

light is the most common limiting factor in forest plant communities,influencing species composition,stand structure,and stand productivity in closed canopy *** vertical light structure is relatively simple under a closed canopy because most light is captured by overstory ***,wind disturbance events create canopy openings from local to landscape scales that increase understory light intensity and vertical light structural *** studied the effects of an EF-1 tornado on horizontal and vertical(***-dimensional)light structure within a Quercus stand to determine how light structure changed with increasing disturbance *** used a two-tiered method to collect photosynthetic photon flux density at 4.67 m and 1.37 m above the forest floor to construct three-dimensional light structure across a canopy disturbance severity gradient to see if light intensity varied with increasing tornado *** indicate that increased canopy disturbance closer to the tornado track increased light penetration and light structure heterogeneity at lower forest *** light intensity correlated with increased sapling density that was more randomly distributed across the plot and had shifted light capture higher in the stand *** penetration through the overstory was most strongly correlated with decreased stem density in the two most important tree species(based on relative dominance and relative density)in the stand,Quercus alba l.(r=-0.31)and Ostrya virginiana(Mill.)***(r=-0.27,plight penetration was most affected by these two *** managers are increasingly interested in patterning silvicultural entries on natural disturbances,they must understand residual stand and light structures that occur after natural disturbance *** providing spatial light data that quantifies light structure post-disturbance,managers can use these results to improve planning required for long-term man

关键词： Photosynthetic photon flux density Midstory Blowdown Heterogeneity

In the shadow of the laser phantom needle cross:dynamic air-plasma aperture sheds light on terahertz microscopy

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light(Science & Applications) 2022年第6期11卷 1032-1033页

作者： daniel Headland Withawat Withayachumnankul Optoelectronics and laser Technology Group Department of Electronics TechnologyUniversidad CarlosⅢde Madrid28911 MadridSpain Terahertz Engineering laboratory School of Electrical and Electronic EngineeringThe University of AdelaideAdelaideSA 5005Australia

Two plasma filaments crossing above the target create a subwavelength window for terahertz microscopy that excludes any subwavelength probe in vicinity.

关键词： laser needle dynamic

Disturbance history,species diversity,and structural complexity of a temperate deciduous forest

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Journal of Forestry Research 2020年第2期31卷 397-414页

作者： Jonathan D.Goode Carson R.Barefoot Justin l.Hart daniel C.Dey Department of Geography University of AlabamaTuscaloosaAL 35487USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Stand structural complexity enhancement is an increasingly popular management objective,especially on public *** stand structures are hypothesized to support a relatively high degree of native forest diversity and be more resistant and resilient to *** structures are characterized by the presence of deadwood and heterogeneity of tree-size classes and tree *** little is known about how discrete disturbance events affect structural complexity and compositional diversity in Quercus-dominated stands at fine spatial scales(***).We established 200.05 ha fixed-radius plots on the Sipsey Wilderness of William *** National Forest in northern Alabama to quantify woody plant species composition and *** were mapped on each plot to quantify overstory structural complexity and compositional *** extracted two cores from all canopy Quercus spp.C 5 cm diameter at breast height to quantify age,recruitment pulses,and reconstruct canopy disturbance *** species diversity in the sampled area was 1.75 for trees,2.08 for saplings,and 1.69 for *** alba had the greatest basal area,and Ostrya virginiana had the highest *** stand exhibited a reverse J-shaped distribution with a q-factor of *** oldest Quercus dated to 1795,and the largest recruitment pulse occurred in the *** mean return interval for intermediateseverity disturbance was 38 *** we documented no relationships between disturbance frequency and compositional diversity at the neighborhood scale(0.05 ha),less frequent disturbance was associated with higher structural complexity(r^2=0.258,p=0.026)at the neighborhood *** suggest that localized disturbance increases species diversity and structural complexity,but these processes are manifest at the stand level and not at the neighborhood *** conclude that the spatial variability(***,shape,orientation,microsite conditions)is likel

关键词： Canopy gap Quercus(oak) Stand development Succession

Spatial-temporal modeling of initial COVID-19 diffusion: The cases of the Chinese Mainland and Conterminous United States

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Geo-Spatial Information Science 2021年第3期24卷 340-362页

作者： daniel Griffith Bin li Department of Geography&Environmental Studies Central Michigan UniversityMount PleasantMichiganUnited States School of Economic Political and Policy SciencesThe University of Texas at DallasRichardsonTexasUnited States

COVID-19 outbreaks in China in late December 2019,then in the United States(US)in early *** the initial wave of diffusion,the virus respectively took 14 and 33 days to spread across the provinces/states in the Chinese mainland and the coterminous US,during which there are 43%and 70%zero entries in the space-time series for China and US respectively,indicating a zero-inflated count process.A logistic growth curve as a function of the number of days since the first case appeared in each of these countries accurately portrays the national aggregate per capita rates of infection for *** paper presents two space-time model specifications,one based upon the generalized linear mixed model,and the other upon Moran eigenvector space-time filtering,to describe the spread of COVID-19 in the initial 19 and 58 days across the Chinese mainland and the coterminous US,*** from these case studies show both models shed new light on the role of spatial structures in COVID-19 diffusion,models that can forecast new cases in subsequent days.A principal finding is that describing the spatiotemporal diffusion of COVID-19 benefits from including a hierarchical structural component to supplement the commonly employed contagion component.

关键词： COVID-19 contagion diffusion hierarchical diffusion moran eigenvector spatial-time filtering random effects

A pentaploid-based linkage map of the ancestral octoploid strawberry Fragaria virginiana reveals instances of sporadic hyper-recombination

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Horticulture Research 2020年第1期7卷 1796-1810页

作者： Thomas M.Davis Yilong Yang lise l.Mahoney daniel C.Frailey Department of Agriculture Nutritionand Food SystemsUniversity of New HampshireDurhamNH 03824USA

The first high-resolution genetic linkage map of the ancestral octoploid(2n=8x=56)strawberry species,Fragaria virginiana,was constructed using segregation data obtained from a pentaploid progeny *** novel mapping population of size 178 was generated by crossing highly heterozygous *** hybrid“lB48”as a paternal parent with diploid(2n=2x=14)Fragaria vesca“Hawaii 4”.The lB48 linkage map comprises 6055 markers genotyped on the Axiom®IStraw90 strawberry SNP *** map consists of 28 linkage groups(lGs)organized into seven homoeology groups of four lGs each,and excludes a small 29th lG of undefined *** member of each homoeology group was assignable to an“A”subgenome associated with ancestral diploid Fragaria vesca,while no other subgenomes were *** an intriguing discrepancy within homoeology group VI,synteny comparisons with the previously published Fragaria×ananassa DA×MO linkage map revealed substantial *** initial map construction,examination of crossover distributions revealed that six of the total 5162(=29 chromosomes/individual×178 individuals)chromosomes making up the data set exhibited abnormally high crossover counts,ranging from 15 to 48 crossovers per chromosome,as compared with the overall mean of 0.66 crossovers per *** of these six hyper-recombinant(HypR)chromosomes occurred in a different lG and in a different *** calculated upon exclusion of the six HypR chromosomes,the canonical(i.e.,broadly representative)lB48 map had 1851 loci distributed over a total map length of 1873 cM,while their inclusion increased the number of loci by 130,and the overall map length by 91 *** of these hyper-recombinant chromosomes points to the existence of a sporadically acting mechanism that,if identified and manipulable,could be usefully harnessed for multiple purposes by geneticists and breeders.

关键词： Fragaria straw linkage