A Simulation Study on the Efficacy of Advanced Belt Restraints to Mitigate the Effects of Obesity for Rear-Seat Occupant Protection in Frontal Crashes

Objective: Recent field data analyses have shown that the safety advantages of rear seats relative to the front seats have decreased in newer vehicles. Separately, the risks of certain injuries have been found to be higher for obese occupants. The objective of this study is to investigate the effects of advanced belt features on the protection of rear-seat occupants with a range of body mass index (BMI) in frontal crashes.

Methods: Whole-body finite element human models with 4 BMI levels (25, 30, 35, and 40 kg/m²) developed previously were used in this study. A total of 52 frontal crash simulations were conducted, including 4 simulations with a standard rear-seat, 3-point belt and 48 simulations with advanced belt features. The parameters varied in the simulations included BMI, load limit, anchor pretensioner, and lap belt routing relative to the pelvis. The injury measurements analyzed in this study included head and hip excursions, normalized chest deflection, and torso angle (defined as the angle between the hip–shoulder line and the vertical direction). Analyses of covariance were used to test the significance (P <.05) of the results.

Results: Higher BMI was associated with greater head and hip excursions and larger normalized chest deflection. Higher belt routing increased the hip excursion and torso angle, which indicates a higher submarining risk, whereas the anchor pretensioner reduced hip excursion and torso angle. Lower load limits decreased the normalized chest deflection but increased the head excursion. Normalized chest deflection had a positive correlation with maximum torso angle. Occupants with higher BMI have to use higher load limits to reach head excursions similar to those in lower BMI occupants.

Discussion and Conclusion: The simulation results suggest that optimizing load limiter and adding pretensioner(s) can reduce injury risks associated with obesity, but conflicting effects on head and chest injuries were observed. This study demonstrated the feasibility and importance of using human models to investigate protection for occupants with various BMI levels. A seat belt system capable of adapting to occupant size and body shape will improve protection for obese occupants in rear seats.     

A Spatially Explicit Model for Mapping Headwater Streams

Headwater streams are the primary sources of water in a drainage network and serve as a critical hydrologic link between the surrounding landscape and larger, downstream surface waters. Many states, including North Carolina, regulate activity in and near headwater streams for the protection of water quality and aquatic resources. A fundamental tool for regulatory management is an accurate representation of streams on a map. Limited resources preclude field mapping every headwater stream and its origin across a large region. It is more practical to develop a model for headwater streams based on a sample of field data that can then be extrapolated to a larger area of interest. The North Carolina Division of Water Quality has developed a cost‐effective method for modeling and mapping the location, length, and flow classification (intermittent and perennial) of headwater streams. We used a multiple logistic regression approach that combined field data and terrain derivatives for watersheds located in the Triassic Basins ecoregion. Field data were collected using a standard methodology for identifying headwater streams and origins. Terrain derivatives were generated from digital elevation models interpolated from bare‐earth Light Detection and Range data. Model accuracies greater than 80% were achieved in classifying stream presence and absence, stream length and perennial stream length, but were not as consistent in predicting intermittent stream length.     

A conceptual model of the social–ecological system of nature-based solutions in urban environments

This article provides a perspective on nature-based solutions. First, the argument is developed that nature-based solutions integrate social and ecological systems. Then, theoretical considerations relating to relational values, multifunctionality, transdisciplinarity, and polycentric governance are briefly outlined. Finally, a conceptual model of the social–ecological system of nature-based solutions is synthesised and presented. This conceptual model comprehensively defines the social and ecological external and internal systems that make up nature-based solutions, and identifies theoretical considerations that need to be addressed at different stages of their planning and implementation The model bridges the normative gaps of existing nature-based solution frameworks and could be used for consistent, comprehensive, and transferable comparisons internationally. The theoretical considerations addressed in this article inform practitioners, policymakers, and researchers about the essential components of nature-based solutions. The conceptual model can facilitate the identification of social and ecological interconnections within nature-based solutions and the range of stakeholders and disciplines involved.     

Mitigation of atrazine, S-metolachlor, and diazinon using common emergent aquatic vegetation

By the year 2050, the population of the United States is expected to reach over 418 million,while the global population will reach 9.6 billion. To provide safe food and fiber, agriculture must balance pesticide usage against impacts on natural resources. Challenges arise when storms cause runoff to be transported to aquatic receiving systems. Vegetated systems such as drainage ditches and constructed wetlands have been proposed as management practices to alleviate pesticide runoff. Twelve experimental mesocosms(1.3 × 0.71 × 0.61 m) were filled with sediment and planted with a monoculture of one of three wetland plant species(Typha latifolia, Leersia oryzoides, and Sparganium americanum).Three mesocosms remained unvegetated to serve as controls. All mesocosms were amended with 9.2 ± 0.8 μg/L, 12 ± 0.4 μg/L, and 3.1 ± 0.2 μg/L of atrazine, metolachlor, and diazinon, respectively, over a 4 hr hydraulic retention time to simulate storm runoff.Following the 4 hr amendment, non-amended water was flushed through mesocosms for an additional 4 hr. Outflow water samples were taken hourly from pre-amendment through8 hr, and again at 12, 24, 48, 72, and 168 hr post-amendment. L. oryzoides and T. latifolia had mean atrazine, metolachlor, and diazinon retentions from 51%–55% for the first 4 hr of the experiment. Aside from S. americanum and atrazine(25% retention), unvegetated controls had the lowest pesticide retention(17%–28%) of all compared mesocosms. While native aquatic vegetation shows promise for mitigation of pesticide runoff, further studies increasing the hydraulic retention time for improved efficiency should be examined.     

Socioeconomic indicators and the survival of the tropical rainforest of cross river state of Nigeria

An internal household survey of socioeconomic indicators in the Cross River State forest communities showed that basic infrastructural facilities such as clean water supply, adequate waste disposal system, good roads and electricity are grossly inadequate. There is a total absence of modern family planning practices in the communities, and population is projected to increase by 44.8% between 2000 and 2015 and 85.4% between 2000 and 2025. The study revealed that about 65% of the population of the rainforest communities consists of subsistence farmers and power chain operators, and besides the 19% of the Cross River State Tropical High Forestry (THF) already reported to have been lost to agriculture and plantation between 1972 and 1991, about 9% was lost between 1991 and 2000. An additional 25% of the THF will be lost by 2025, leaving only 470600 hectares (4706 km²). With 84.1% of community members having an annual income less than $300, the survival potential of the Cross River State rainforest in the next fifty years is very low, unless an effective forest management programme is encouraged by government in partnership with all stakeholders.     

Eco‐Value,Sustainability, and Shareholder Value: Driving Environmental Performance to the Bottom Line

Contrary to popular assumptions, superior eco‐efficiency is associated with superior financial performance throughout a range of industries. In fact, environmental leaders typically outperform laggards by a substantial margin. © 2001 John Wiley & Sons, Inc.     

A case for 2-body material removal in prime LED sapphire substrate lapping and polishing

An alternative, and potentially better, means to process prime LED sapphire wafers is proposed. A brief history of material removal mechanisms suggests that brittle materials can be abraded in a ductile regime and that this can be a superior mode of removal. Advantages in material removal rate, surface finish and subsurface damage for a 2-body ductile removal of sapphire are shown relative to 3-body material removal. A major difficulty with this approach may be getting the LED manufacturing industry to understand that the appearance of the sapphire surface is quite different, unfamiliar yet predictable. Finally, some potential alternative process approaches are discussed that utilize 2-body material removal.