Quantifying driver cell phone use at signalized intersections using software-defined radio

Objective: This article outlines a data collection process that quantifies driver cell phone use using a software-defined radio (SDR) at a signalized intersection. Cell phone use while driving has been shown to be factor that increases the risk of a crash incident. Both operational and enforcement strategies can be applied at locations where high driver cell phone use is identified.

Methods: A baseline driver cell phone use observation was made at the intersection, where 9,699 vehicles were observed at the intersection of Carlton Road and State Route 31 (Pennington Road) in Ewing, New Jersey. An SDR cell phone detection device created as part of this study was then deployed at the same intersection to determine whether the SDR device could detect an active cell phone signal. The identification of vehicle cell phone activity using the SDR was conducted a sample of 4,000 vehicles. A visual observation, along with a motion detection camera, was made alongside the SDR to visually confirm cell phones use.

Results: Of the 4,000 vehicles sampled using the SDR cell phone detection device, 6.1% of the a.m. peak travel time and 7.6% of the p.m. peak travel time had an active cellular device. A concurrent visual field verification of driver cell phone use showed that approximately 57% (a.m. peak) and 67% (p.m. peak) of the SDR-detected cell phones were visually confirmed to be associated with distracted cell phone use.

Conclusions: Once characterized, the frequency of driver cell phone use can be used to justify changes to signal timing protocols. These adjustments could include extending the signal’s “all-red time” or holding “yellow time” longer in order to properly clear the intersection. These data can also be used to identify locations that may require more enforcement measures to dissuade driver cell phone use. Furthermore, the impact of anti–cell phone campaigns or new laws can be quantified by measuring before and after cell phone use in the near term rather than waiting for crash studies at intersections to be completed and analyzed.     

Total mercury, organic mercury and selenium in liver and kidney of a South American coastal dolphin

Selenium and total and organic mercury were determined in the liver and kidney of franciscana dolphin (Pontoporia blainvillei) incidentally caught in fishing nets along two Brazilian coastal areas (southeast and south). Regional differences in the concentrations of these contaminants were observed in P. blainvillei. Liver showed the highest organic and total mercury. In general, samples of individuals collected at the southern of Brazil had the highest concentrations of selenium and total and organic mercury. No significant gender differences were observed. Growth stage influenced the accumulation of these contaminants in both organs, and hepatic concentrations increased with the body length, according to the sampling area. Molar mercury and selenium concentrations in liver were significantly correlated, with a Se:Hg ratio close to 4. The among-site differences we found may be related to differences in preferred prey, bioavailability in the marine environment, environmental conditions, or these individuals may belong to distinct populations.     

用分布式混合试验系统模拟结构的倒塌行为

采用分布式混合试验系统模拟四层钢结构框架在强震下的倒塌行为。变形集中的首层作为试验对象,而上部结构作为数值子结构。各子结构通过协调器满足界面上的平衡和协调条件,并被协调器的输入输出接口封装起来。采用柔性的试验方案,可以在当前有限控制精度的限制下,灵活地处理边界条件。试验结果与日本E-D efense振动台足尺试验结果进行了对比,得到了类似的倒塌机制,证明混合试验有能力进行结构倒塌模拟,而误差主要来自于模型简化。     

Monitoring, fault detection and operation prediction of MSW incinerators using multivariate statistical methods

This work proposes the application of two multivariate statistical methods, principal component analysis (PCA) and partial least square (PLS), to a continuous process of a municipal solid waste (MSW) moving grate-type incinerator for process control - monitoring, fault detection and diagnosis - through the extraction of information from historical data. PCA model is built for process monitoring capable of detecting abnormal situations and the original 16-variable process dimension is reduced to eight, the first 4 being able to capture together 86% of the total process variation. PLS model is constructed to predict the generated superheated steam flow rate allowing for control of its set points. The model retained six of the original 13 variables, explaining together 90% of the input variation and almost 98% of the output variation. The proposed methodology is demonstrated by applying those multivariate statistical methods to process data continuously measured in an actual incinerator. Both models exhibited very good performance in fault detection and isolation. In predicting the generated superheated steam flow rate for its set point control the PLS model performed very well with low prediction errors (RMSE of 3.1 and 4.1).     

Feeding the world sustainably: knowledge governance and sustainable agriculture in the Argentine Pampas

This article discusses the role of knowledge governance arrangements in the mainstreaming of sustainable practices, in particular, in the creation, sharing and use of integrated and contextualized knowledge. That is, knowledge which accounts for the social, economic, institutional, and ecological dimensions of potentially sustainable practices, and which considers the need to adapt generic practices to the sustainability requirements of specific places. An actor-centered approach is proposed for the study of the historical evolution of knowledge governance arrangements in order to understand their role in the adoption of sustainable practices. The approach is applied to explain the rapid adoption of no-till agriculture in the Argentine Pampas. A radical knowledge governance transformation occurring in this region during the 1990s led to increasing knowledge exchange and pushing sustainability practices to the top of key actors’ agendas. This embracing of no-till agriculture illustrates the crucial role played by farmers’ associations as boundary organizations: linking farmers with actors specialized in the generation of scientific knowledge and technology. This case reveals that sustainability transitions can be fostered through knowledge governance arenas characterized by: (a) promoting public–private collaboration through boundary organizations, (b) assigning private actors a leading role in the adoption of sustainability practices at the production unit scale, (c) fostering the public sector competence in regional and socio-ecological research, and (d) addressing the heterogeneous needs of knowledge users. However, the case also shows that the success of no-till agriculture in the Pampas is pushing the agriculturization of surrounding areas where this practice is largely unsustainable. This finding suggests that present knowledge governance arrangements fail to contextualize practices that are potentially sustainable.     

Determination of estrogenic activity in the river Chienti (Marche Region, Italy) by using in vivo and in vitro bioassays

Environmental estrogen-like compounds (i.e. xenoestrogens) are a variety of pollutants, ranging from synthetic to natural occurring molecules, that are found in surface and waste waters over a wide range of concentrations. In aquatic environment, the overall estrogenic activity is often due to the presence of a mixture of chemicals and their degraded products which can induce synergistic effects. Current strategies for monitoring estrogen-like chemicals are based on the use of a battery of in vivo and in vitro ecotoxicological tests. In this regard, the aim of the present work was to carry out a bio-monitoring study for testing estrogenicity of the Chienti river (Marche Region, Italy) by using both an E-screen and a vitellogenin (Vtg) induction assay in juvenile goldfish. Three sites were used for analysis, localized at the mouth (sampling point 1), in the middle (sampling point 2) and at the origin (sampling point 3) of Chienti river. For most of the water samples (i.e. samples collected at sampling points 2 and 3), clear estrogenic activity was detected in the E-screen assay suggesting different proliferation activities in function of the collecting site. In contrast, the Vtg ELISA demonstrated that water samples collected from each sampling point were estrogenic. Overall, we showed for the first time that the estrogenic activities in water samples from the Chienti river were significant in both in vivo and in vitro; we also observed a different sensitivity between bioassays.     

An indicator tool for assessing local vulnerability to climate change in the Mexican agricultural sector

To propose specific adaptation strategies in the agricultural sector based on vulnerability to climate variability and climate change at the local level, we built a vulnerability index using an indicator tool at a fine spatial scale. This index was applied as a case study in the municipality of Guasave, Sinaloa, Mexico, at the basic census area (BCA) level. We used a total of 37 variables organized into three groups with equal weighting: exposure (13), sensitivity (13), and adaptive capacity (11). From the 20 rural BCAs located in the study area, eight were categorized as having very low vulnerability; five had low vulnerability; two had medium vulnerability because of the lack of basic services (sewers, water, and electricity) and a high rural population density; three had high vulnerability due to a high frequency of days with temperatures below 5 °C and the lack of basic services; and two had very high vulnerability, characterized by a high percentage of production units (PUs) with losses due to climate factors, a high rural population density, and a high frequency of days with temperatures below 5 °C. Approximately 50 % of the municipal rural population lives in BCAs vulnerable to climate change. This methodology allowed us to identify the most susceptible agricultural areas at the local level and the variables that require more attention so that we can propose adaptation strategies and minimize vulnerability due to climate change.     

Seabird mortality induced by land‐based artificial lights

Artificial lights at night cause high mortality of seabirds, one of the most endangered groups of birds globally. Fledglings of burrow‐nesting seabirds, and to a lesser extent adults, are attracted to and then grounded (i.e., forced to land) by lights when they fly at night. We reviewed the current state of knowledge of seabird attraction to light to identify information gaps and propose measures to address the problem. Although species in families such as Alcidae and Anatidae can be grounded by artificial light, the most affected seabirds are petrels and shearwaters (Procellariiformes). At least 56 species of Procellariiformes, more than one‐third of them (24) threatened, are subject to grounding by lights. Seabirds grounded by lights have been found worldwide, mainly on oceanic islands but also at some continental locations. Petrel breeding grounds confined to formerly uninhabited islands are particularly at risk from light pollution due to tourism and urban sprawl. Where it is impractical to ban external lights, rescue programs of grounded birds offer the most immediate and employed mitigation to reduce the rate of light‐induced mortality and save thousands of birds every year. These programs also provide useful information for seabird management. However, these data are typically fragmentary, biased, and uncertain and can lead to inaccurate impact estimates and poor understanding of the phenomenon of seabird attraction to lights. We believe the most urgently needed actions to mitigate and understand light‐induced mortality of seabirds are estimation of mortality and effects on populations; determination of threshold light levels and safe distances from light sources; documentation of the fate of rescued birds; improvement of rescue campaigns, particularly in terms of increasing recovery rates and level of care; and research on seabird‐friendly lights to reduce attraction.     

Occurrence of <Emphasis Type="Italic">Pepper Mild Mottle Virus</Emphasis> (PMMoV) in Groundwater from a Karst Aquifer System in the Yucatan Peninsula,Mexico

The Yucatan Peninsula of Mexico hosts a karst aquifer system that is the only source of freshwater for the area; however, it is vulnerable to human-mediated contamination. Pepper mild mottle virus (PMMoV) is one of the most abundant RNA viruses associated with human feces, making it a viable indicator for tracking fecal pollution in aquatic environments, including groundwater. In this study, groundwater samples collected from a karst aquifer from fresh and brackish water locations were analyzed for fecal indicator bacteria, somatic and male F+ specific coliphages, and PMMoV during the rainy and dry seasons. Total coliform bacteria were detected at all sites, whereas Escherichia coli were found at relatively low levels <40 MPN/100 ml. The highest average concentrations of somatic and male F+ specific coliphages were 920 and 330 plaque forming units per 100 ml, respectively, detected in freshwater during the rainy season. PMMoV RNA was detected in 85% of the samples with gene sequences sharing 99–100% of nucleotide identity with PMMoV sequences available in GenBank. Quantification of PMMoV genome copies (GC) by quantitative real-time PCR indicated concentrations ranging from 1.7 × 10¹ to 1.0 × 10⁴ GC/L, with the highest number of GC detected during the rainy season. No significant correlation was observed between PMMoV occurrence by season or water type (p > 0.05). Physicochemical and indicator bacteria were not correlated with PMMoV concentrations. The abundance and prevalence of PMMoV in the karst aquifer may reflect its environmental persistence and its potential as a fecal indicator in this karst aquifer system.