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1.
Capsule Habitat associations of breeding birds in a complex coastal environment are clear, interpretable and mostly consistent between years.

Aims To match archive territory mapping data with historical aerial photographs and develop data handling and analytical techniques for the study of bird–habitat relationships.

Methods Bird registrations were digitized from archive British Trust for Ornithology Common Birds Census maps and habitat characteristics from contemporaneous aerial photographs. The resulting maps were overlaid and ranks of habitat preference for 15 species calculated using compositional analysis. Similarity analysis identified species with consistent habitat profiles across years. Cluster analysis identified groups of species with similar patterns of habitat use.

Results A total of 5400 registrations of 15 species in 14 habitats were analysed. Of these, 13 species showed stable patterns of habitat association across survey years. Clear differences and similarities in habitat preferences among the species were identified. The results may be used to inform conservation and management programmes in this and similar environments.

Conclusions Extensive archives of bird survey data can be used to study bird–habitat relationships and to measure the effects of natural and anthropogenic environmental change if contemporaneous aerial photographs can be sourced.  相似文献   

2.
3.
Purpose

Organizational life cycle assessment (O-LCA) is an emerging method to analyze the inputs, outputs, and environmental impacts of an organization throughout its value chain. To facilitate the method’s application, the Guidance on Organizational Life Cycle Assessment was published within the UNEP/SETAC Life Cycle Initiative and applied by 12 “road-testing” organizations. In this paper, different aspects of the road testers’ studies are displayed and analyzed according to the feedback of the road testers.

Methods

An anonymous survey about the method application was conducted among the road testers. The analysis assessed, among others: (i) which goals the organizations initially pursued and their achievement; (ii) how previous experience with environmental tools contributed to the study design; (iii) which methodological options were chosen (like the scope of the study, data collection approaches, impact assessment methods and tools, and data sources); and (iv) which methodological challenges were faced.

Results and discussion

The survey showed that analytical goals were of priority for most road testers and obtained a higher achievement level than managerial and societal goals for which either long-term measures or the inclusion of stakeholders are needed. Previous experience with product- or organization-related tools considering the whole life cycle proves useful due to available data and/or organizational models. The categorization of organizational activities, data collection, data quality assessment, and interpretation proved being the most challenging methodological elements. In addition, three cross-cutting issues of method application were identified: aligning the O-LCA study to previous environmental activities, designing the study, and availability of personnel and software resources.

Conclusions

The road-testing organizations verified the applicability and usefulness of the O-LCA Guidance and significantly widened the pool of case studies available. On the other hand, additional guidance for methodological challenges particular of the organizational level, the availability of software tools able to support O-LCA application, region-specific LCI databases, and a broadly recognized data quality assessment scheme would facilitate conducting O-LCA case studies.

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4.
Purpose

Winter road maintenance in the Nordic climate is demanding due to challenging weather conditions, high precipitation, and icy conditions. As a leading country in the transition to low-emission transport, Norway must work to reduce their emissions while providing a safe level of service through winter maintenance operations. This article investigates the environmental impacts of winter road maintenance (WRM) in Norway both today and under a climate change scenario predicted for 2050.

Methods

Life cycle assessment (LCA) is used to evaluate the environmental impact of the functional unit “average winter road maintenance in Norway on national and county roads per km.lane.” The ReCiPe (hierarchy) method was used to identify and categorize emissions related to WRM to show how different factors affect the system and to reveal hidden emissions hotspots. Real-time data from WRM vehicles were used to determine how fuel consumption is affected by gradient and weather. Producers and operators provided other relevant information on WRM vehicles. Official reports supplied information on deicer quantities used and the total distance driven by WRM vehicles in Norway.

Results and discussion

The quantity of deicer used is the main source of emissions contributing toward all impact categories. The effect of deicer is likely to be even higher in certain impact categories. The environmental impact of the deicer after application is not included. The representation of WRM in existing emissions data is limited despite the considerable amount of deicer applied and the long distances that WRM vehicles travel. The results document how energy use throughout the system is another important source of emissions. Various parameters, such as road gradient, vehicle properties, driver behavior, and weather, affect the fuel consumption of WRM vehicles, with weather being the most important of these.

Conclusions

Significant potential for emissions reductions from WRM was found, and WRM operations should be included in cold-climate road LCA studies. The environmental impacts of deicer application are especially high compared to the mechanical clearing of roads and contribute strongly to impact categories such as terrestrial, freshwater, and human toxicity and to the formation of particulate matter.

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5.
Capsule Counts with precision comparable to those of an expert observer can be achieved automatically.

Aims To develop an open-source freeware program that automatically extracts and counts the number of birds in aerial images of dense aggregations.

Methods Software was developed and validated using aerial photographs of Greater Flamingo colonies from France, Turkey and Mauritania. We used a stochastic approach based on object processes. The objects representing flamingos were defined as ellipses, and the software detected these and produced a count. Details of the procedure are provided in electronic supplementary material. The energy is extracted by a birth-and-death algorithm, leading to the total number of birds.

Results This procedure gave counts with precision comparable to manual counts of the aerial photographs by an expert (<5% difference). The procedure does not need any supervision of the extraction by an operator, thus reducing the processing time required to get the estimate of bird numbers in the image from?>4 h to 20 min on average.

Conclusion This open-source freeware should be useful for ornithologists and wildlife managers.  相似文献   

6.
Purpose

Carbon emission from roads is an important contributor of a nation’s greenhouse gas emission that causes climate change. However, the existing life cycle assessment (LCA) analysis of road carbon emissions focus on project-level, ignoring regional differences. Significant challenges remain in developing regional road’s carbon emission mitigation strategies. This study estimates the quantity of carbon emissions from roads in China and calculated the regional equity of road carbon emissions.

Methods

An improved LCA approach, which considered the regional difference of raw materials’ carbon emissions, carbon emissions caused by traffic jam and road category, was applied to calculate the quantity of carbon emissions of roads. Sensitive analysis was conducted to find the key influential factors. Gini coefficient was used to calculate the equity degree of carbon emissions by roads based on the LCA results. The decomposition model of Gini coefficient is applied to analyze the causes of carbon emission differences.

Results

The total national carbon emissions by roads in 2019 increased by 2.2 times compared to 2009. Carbon emission from roads in the operation phase increased from 62% in 2009 to 83% in 2019. The functional unit for expressway in this study ranging from 1646 to 1794 t CO2e/km in 31 provinces. An estimated uncertainty of plus or minus 4% of the traffic flow allocation between expressway and other roads makes an increase of 38% or a decrease of 15% of the life cycle emission. The overall Gini coefficient of carbon emissions from roads in China is under the warning line of 0.4. Outer inequity between regions contributes 88.83% of the whole inequity and the most developed three regions contribute 66.23%.

Conclusions

Large quantity of road construction in the past in China makes the burden of carbon emission transfer from the construction phase to the operation phase. Regional differences of raw materials’ carbon emissions, traffic jam, and road hierarchy are important factors influencing the LCA-based estimation of road carbon emission. To improve the national equity degree of road carbon emission, quota allocation of road carbon emission rights between regions and cross-regional carbon emission reduction policies would help.

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7.

Word responses have been used to dedde whether pictures of expressive faces or postures portray truthful expressions. Previous investigators have assumed words are used only as symbols of “meaning”. They did not appreciate the use of words as symbols of “sorting”. If one viewer calls two photographs “angry” and another viewer calls the same two photographs “happy,” the viewers may disagree in their “meanings” but they agree in their ‘sortings” both agree each photograph portrays the same expression. Sorting groups reveal how the visual system processes photographic images.  相似文献   

8.
Abstract

Male and female students were asked to select from groups of photographs projected on slides the individual preferred as a mate in a long‐term husband‐wife relationship. The students were later shown some of the same photographs several times to familiarize them with these individuals. The students were subsequently shown the same groups of photographs from which they initially indicated mating preferences and were again asked to indicate their preferences. When familiarization immediately preceded the final preference selections, both male and female students switched preferences and chose individuals with whom they had been familiarized approximately twice as often as they switched preferences and chose individuals with whom they had not been familiarized. When familiarization preceded the final preference selection by seven days, the frequency of switching and choosing the familiar type did not increase. These results and the possible evolutionary basis for the results are discussed.  相似文献   

9.
Purpose

The environmental impacts of electricity generation are a critical issue towards sustainability and thus an important research topic in several countries. The life cycle assessment methodology has been widely employed to assess electricity generation. However, there are still gaps in research to be explored within this theme. Therefore, this paper aims to conduct a systematic theoretical analysis of the state of the art of the scientific research on LCA of electricity generation systems in the world.

Methods

A critical review of 47 studies was conducted. The study is comprehensive in the analysis of the main aspects of the identified high impact studies as follows: authors, countries, universities, keywords, journals, number of citations, life cycle impact assessment methods, impact categories, software tools, and databases. The Methodi Ordinatio was applied to rank the studies in terms of impact factor and number of citations, pointing out high impact research.

Results and discussion

Wind and solar powers have two of the smallest impact indices in their generation in terms of global warming, compared to other sources. The ecoinvent database was the most used among the studies analyzed, providing data for potential environmental impacts. The most frequently used impact category in the assessments was climate change. The studies are not equally distributed but most of them are concentrated in European countries. In some countries, clean sources seem promising due to their capacity to generate electricity in places with high wind incidence and high capacity for sunlight capture.

Conclusions

The conclusions of this article summarize the characteristics of existing literature and provide suggestions for future work. The results of the study can also be used to promote development actions and foment changes in energy matrices in a global context. The main studies in this area point that in the future, the main sources for electricity generation will be renewable ones, since life cycle assessment of electricity generation systems has been seeking to generate knowledge to support informed decision-making.

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10.
《Journal of bryology》2013,35(1):56-68
Abstract

A new species of Pseudocrossidium R.S.Williams, P. exiguum M.J.Cano &; J.A.Jiménez, is described from South America (Argentina, Brazil and Peru). The species is distinguished morphologically by its lingulate to oblong-ovate leaves, leaf marginal cells not or scarcely differentiated from inner, costa ending below apex or percurrent, and semicircular to elliptical in cross-section with two guide cells, scarcely differentiated perichaetial leaves and peristome of short and straight teeth. Drawings and light microscope photographs of the new species are provided. The principal distinctive characters that separate it from the nearest species of Pseudocrossidium and related genera are discussed.  相似文献   

11.
Abstract

This paper reviews 53 records of the Whimbrel (Numenius phaeopus) in Bulgaria (1912–1989) from published and unpublished sources. The phonology, distribution, ecology and behaviour of these migrants are described and discussed. Attention is drawn to “pale” Whimbrels which may belong to the rare subspecies albuaxillaris.  相似文献   

12.
《Plains anthropologist》2013,58(55):55-59
Abstract

The first controlled excavation of a Clovis site in Iowa revealed a concentration of complete and fragmentary Clovis Fluted projectile points. The site, in eastern Iowa, is interpreted as a projectile point cache destroyed by agricultural implements. Measurements and photographs are provided to facilitate the comparison of the collection with assemblages from other states.  相似文献   

13.
Book reviews     

Seeing anthropology Karl G. Heider, Seeing Anthropology: Cultural Anthropology through Film. Boston: Allyn &; Bacon, 1997. xx+347 pp., photographs, maps, glossary, bibliography; with two half‐inch NTSC videotapes totalling 3hrs., 11 mins. US $37.75 nett.

History and politics Faris, James C. Navajo and Photography: A Critical History of the Representation of an American People; xv, 392 pp., 263 illus., notes, appendix, bibliography, index. Albuquerque: University of New Mexico Press, 1996. $39.95 (hdbd.)

The Anthropology of Visual Communication Canevacci, Massimo, Antropologia della comunicazione visuale. Genova: Costa &; Nolan, 1995. 260 pp., photographs, bibliography. Lire 34,000, paper.  相似文献   

14.
ABSTRACT

Capsule: There was significant variation on the incidence of road traffic mortality across bird species, due to seasonal and weather effects but also due to differences between years.

Aims: To assess patterns of mortality due to traffic collision for six common bird species over a period of nine years in relation to seasonality and weather.

Methods: Road mortality surveys were performed on four road sections from 2005 to 2013 in southern Portugal. The analysis controlled for survey frequency, and carcass persistence and detectability.

Results: Overall, bird mortality decreased over time and was generally higher during spring and summer months. The lack of strong relationships between the weather variables and the observed mortality patterns suggests the existence of additional factors important in explaining the observed trends.

Conclusions: Our study provides evidence that bird mortality due to collision with vehicles may change between years and was highest during the breeding season. This could have population consequences, and highlights the need to further address large temporal scales in roadkill research.  相似文献   

15.
Capsule A long-term decline on this habitat is shown to be associated with the intensification of agricultural management, particularly the occurrence of field drainage.

Aims To assess long-term trends in the number of breeding Lapwing and determine the relationship between these trends and changes in agricultural management on an upland study area.

Methods Breeding Lapwing were counted along two road transects in nine years between 1980 and 2002, and on one extensive plot in 1980, 1990 and 2000. Counts along the road transects were made from a vehicle and the fields used for nesting were recorded. Changes in field management along the transects were monitored annually between 1980 and 1990, and habitat composition assessed in 1980, 1985, 1990 and 2000.

Results During the first 20 years of study the number of breeding Lapwing declined substantially on all three count areas and by 77% overall, with further declines on both transects in 2002. The area of unimproved grassland and arable on these transects also declined substantially due to conversion to improved grass. Fields that comprised either unimproved grassland or arable were most likely to hold nesting Lapwing, while the chance of a field losing its nesting Lapwing was positively associated with the occurrence of drainage. Drainage and conversion to improved grass were closely linked.

Conclusions Agricultural intensification is a probable cause of decline in the number of breeding Lapwing in upland areas. Such declines may have been widespread in upland areas following increased agricultural intensification in recent decades.  相似文献   

16.
Abstract

On the migration of the Grey Plover Pluvialis squatarola, in Bulgaria: 137 Bulgarian records (1891 – 1989) were compiled from published and unpublished sources and reviewed. Distribution, phenology, ecology and ethology are described and discussed in comparison with other countries of the Black Sea region.  相似文献   

17.
An  Shaokun  Ma  Liang  Wan  Lin 《BMC genomics》2019,20(2):77-92
Background

Time series single-cell RNA sequencing (scRNA-seq) data are emerging. However, the analysis of time series scRNA-seq data could be compromised by 1) distortion created by assorted sources of data collection and generation across time samples and 2) inheritance of cell-to-cell variations by stochastic dynamic patterns of gene expression. This calls for the development of an algorithm able to visualize time series scRNA-seq data in order to reveal latent structures and uncover dynamic transition processes.

Results

In this study, we propose an algorithm, termed time series elastic embedding (TSEE), by incorporating experimental temporal information into the elastic embedding (EE) method, in order to visualize time series scRNA-seq data. TSEE extends the EE algorithm by penalizing the proximal placement of latent points that correspond to data points otherwise separated by experimental time intervals. TSEE is herein used to visualize time series scRNA-seq datasets of embryonic developmental processed in human and zebrafish. We demonstrate that TSEE outperforms existing methods (e.g. PCA, tSNE and EE) in preserving local and global structures as well as enhancing the temporal resolution of samples. Meanwhile, TSEE reveals the dynamic oscillation patterns of gene expression waves during zebrafish embryogenesis.

Conclusions

TSEE can efficiently visualize time series scRNA-seq data by diluting the distortions of assorted sources of data variation across time stages and achieve the temporal resolution enhancement by preserving temporal order and structure. TSEE uncovers the subtle dynamic structures of gene expression patterns, facilitating further downstream dynamic modeling and analysis of gene expression processes. The computational framework of TSEE is generalizable by allowing the incorporation of other sources of information.

  相似文献   

18.
19.

A selection of pages is presented from an unpublished book layout of photographs made by John Collier Jr. and Mary E.T. Collier in Peru during the 1950s, with a brief introduction and afterword by Malcolm Collier.  相似文献   

20.
Purpose

Objective uncertainty quantification (UQ) of a product life-cycle assessment (LCA) is a critical step for decision-making. Environmental impacts can be measured directly or by using models. Underlying mathematical functions describe a model that approximate the environmental impacts during various LCA stages. In this study, three possible uncertainty sources of a mathematical model, i.e., input variability, model parameter (differentiate from input in this study), and model-form uncertainties, were investigated. A simple and easy to implement method is proposed to quantify each source.

Methods

Various data analytics methods were used to conduct a thorough model uncertainty analysis; (1) Interval analysis was used for input uncertainty quantification. A direct sampling using Monte Carlo (MC) simulation was used for interval analysis, and results were compared to that of indirect nonlinear optimization as an alternative approach. A machine learning surrogate model was developed to perform direct MC sampling as well as indirect nonlinear optimization. (2) A Bayesian inference was adopted to quantify parameter uncertainty. (3) A recently introduced model correction method based on orthogonal polynomial basis functions was used to evaluate the model-form uncertainty. The methods are applied to a pavement LCA to propagate uncertainties throughout an energy and global warming potential (GWP) estimation model; a case of a pavement section in Chicago metropolitan area was used.

Results and discussion

Results indicate that each uncertainty source contributes to the overall energy and GWP output of the LCA. Input uncertainty was shown to have significant impact on overall GWP output; for the example case study, GWP interval was around 50%. Parameter uncertainty results showed that an assumption of ±?10% uniform variation in the model parameter priors resulted in 28% variation in the GWP output. Model-form uncertainty had the lowest impact (less than 10% variation in the GWP). This is because the original energy model is relatively accurate in estimating the energy. However, sensitivity of the model-form uncertainty showed that even up to 180% variation in the results can be achieved due to lower original model accuracies.

Conclusions

Investigating each uncertainty source of the model indicated the importance of the accurate characterization, propagation, and quantification of uncertainty. The outcome of this study proposed independent and relatively easy to implement methods that provide robust grounds for objective model uncertainty analysis for LCA applications. Assumptions on inputs, parameter distributions, and model form need to be justified. Input uncertainty plays a key role in overall pavement LCA output. The proposed model correction method as well as interval analysis were relatively easy to implement. Research is still needed to develop a more generic and simplified MCMC simulation procedure that is fast to implement.

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