Transport and fate of dissolved organic carbon in the Lake Pontchartrain esutary,Louisiana, U.S.A.

Cycling dynamics of dissolved organic carbon (DOC) were examinedin Lake Pontchartrain estuary, Louisiana, in relation to changesin freshwater inputs. DOC concentrations ranged from 5.3 to 8.5mg C L-1 reaching their highest during high river inflow.The percentage of DOC represented by HMW DOC (or colloidal material)was greatest (ca. 11%) at stations where freshwaterdischarge from rivers and surrounding wetlands was most significant.Moreover, the lignin-phenol content of this material (ranged from 0.09 to 0.33 and from 0.11 to 0.39)confirmed that a significant fraction of colloidal organic carbon wasderived from terrestrial sources. Riverine and benthic fluxes representedthe dominant sources of DOC to the estuary. On an annual basis, riverineand benthic DOC concentrations were estimated to be 2.8 ×10 10 g C yr-1 and 8.8 × 10 10 g C yr-1, respectively, while the totalDOC pool in the estuary was 3.8 × 10 10 gC. Annual average concentrations of dissolved inorganic carbon (DIC)(1298 M) and pCO2 (5774 atm)were comparable to those found in other freshwater systems that reachedCO2 saturation levels. Net losses of DOC in the LakePontchartrain estuary appeared to be primarily controlled by heterotrophicconsumption (conversion of CO2) – whichmay have been amplified by the long residence time (approximately 120days) of DOC in this system.     

The Rise of Partisanship and Super-Cooperators in the U.S. House of Representatives

It is widely reported that partisanship in the United States Congress is at an historic high. Given that individuals are persuaded to follow party lines while having the opportunity and incentives to collaborate with members of the opposite party, our goal is to measure the extent to which legislators tend to form ideological relationships with members of the opposite party. We quantify the level of cooperation, or lack thereof, between Democrat and Republican Party members in the U.S. House of Representatives from 1949–2012. We define a network of over 5 million pairs of representatives, and compare the mutual agreement rates on legislative decisions between two distinct types of pairs: those from the same party and those formed of members from different parties. We find that despite short-term fluctuations, partisanship or non-cooperation in the U.S. Congress has been increasing exponentially for over 60 years with no sign of abating or reversing. Yet, a group of representatives continue to cooperate across party lines despite growing partisanship.     

Water and Food Consumption Patterns of U.S. Adults from 1999 to 2001

Objective: High water consumption has been proposed as an aid to weight control and as a means of reducing the energy density of the diet. This study examines the relationship between water consumption and other drinking and eating patterns. Research Methods and Procedures: The National Health and Nutrition Examination Survey 1999 to 2001, with responses from 4755 individuals ≥18 years of age, provides the data for this cross‐sectional analysis. A cluster analysis was performed using z‐scores of specific food and beverage consumption to examine patterns. A multinomial logit analysis was used to examine sociodemographic characteristics of each dietary pattern and to examine the effects of water consumption on the likelihood of consuming a non–dairy caloric beverage. All results were weighted to be nationally representative and controlled for design effects. Results: Within the sample, 87% consumed water, with an average daily consumption of 51.9 oz (1.53 liters) per consumer. Water consumers drank fewer soft/fruit drinks and consumed 194 fewer calories per day. Water consumers (potentially a self‐selected sample) consumed more fruits, vegetables, and low‐ and medium‐fat dairy products. Four distinct unhealthy dietary patterns were found that included little or no water consumption. Older and more educated persons used healthier food patterns. Mexican dietary patterns were much healthier than dietary patterns of blacks. Discussion: Water consumption potentially is a dietary component to be promoted, but much more must be understood about its role in a healthy diet. Because high water consumption is linked with healthier eating patterns—patterns more likely to be followed by higher‐educated, older adults—the target of water promotion and healthy diet options should focus on younger and less educated adults.     

Benthic microbial respiration in Appalachian Mountain, Piedmont, and Coastal Plains streams of the eastern U.S.A.

1. Benthic microbial respiration was measured in 214 streams in the Appalachian Mountain, Piedmont, and Coastal Plains regions of the eastern United States in summer 1997 and 1998. 2. Respiration was measured as both O₂ consumption in sealed microcosms and as dehydrogenase activity (DHA) of the sediments contained within the microcosms. 3. Benthic microbial respiration in streams of the eastern U.S., as O₂ consumption, was 0.37 ± 0.03 mg O₂ m^–2 day^–1. Respiration as DHA averaged 1.21 ± 0.08 mg O₂ m^–2 day^–1 4. No significant differences in O₂ consumption or DHA were found among geographical provinces or stream size classes, nor among catchment basins for O₂ consumption, but DHA was significantly higher in the other Atlantic (non‐Chesapeake Bay) catchment basins. 5. Canonical correlation analyses generated two environmental axes. The stronger canonical axis (W₁) represented a chemical disturbance gradient that was negatively correlated with signatures of anthropogenic impacts (ANC, Cl^–, pH, SO₄²), and positively correlated with riparian canopy cover and stream water dissolved organic carbon concentration (DOC). A weaker canonical axis (W₂) was postively correlated with pH, riparian zone agriculture, and stream depth, and negatively correlated with DOC and elevation of the stream. Oxygen consumption was significantly correlated with W₂ whereas DHA was significantly correlated with W₁. 6. The strengths of the correlations of DHA with environmental variables, particularly those that are proven indicators of catchment disturbances and with the canonical axis, suggest that DHA is a more responsive measure of benthic microbial activity than is O₂ consumption.     

Resource Use and Waste Generation by the Tourism Industry on the Big Island of Hawaii

A survey of the tourism industry on the island of Hawaii (the Big Island) in the state of Hawaii in the United States was conducted to collect baseline information on major resources (energy, food, and water consumption) and waste generation from five tourism sectors: accommodations, food and beverages (restaurants), golf courses, tourism services (tours), and rental cars. The questionnaire was developed and 50 establishments from the target sectors participated in this survey. Resource consumption and waste generation were calculated by the number of establishments, employees, and visitors. Using these factors and island‐wide statistics (the number of establishments, job counts, and visitors), this study estimated the current status of island‐wide water, food, and energy consumption and waste generation by these five sectors of the tourism industry. The estimate shows that the tourism sectors surveyed for this study account for 21.7% of the island's total energy consumption, 44.7% of the island‐wide water consumption, and 10.7% of the island‐wide waste generation. Using a per guest emission factor (such as per employee, guest room, and seat) provided in this study, the owners and managers of tourism establishments can calculate a baseline for each resource input and output. This is essential information to improve the industry's efficiency and result in economic savings.     

RESIDENCE PATTERNS OF BOTTLENOSE DOLPHINS (TURSIOPS TRUNCATUS) IN THE STONO RIVER ESTUARY, CHARLESTON COUNTY, SOUTH CAROLINA, U.S.A.

Residence patterns of inshore bottlenose dolphins ( Tursiops truncatus ) in the Stono River estuary, Charleston County, South Carolina were investigated as part of a larger effort to better understand stock structure of these dolphins along the east coast of the United States. Eighty-seven small-boat surveys for bottlenose dolphins were conducted from October 1994 through January 1996. Dolphins were sighted during all surveys. Approximately 304 h were spent surveying the study area; 64% ( n = 196 h) of this time was spent observing and videotaping dolphins. A catalog, containing 112 individually identified dolphins was compiled. Thirty-two percent ( n = 36) of identified dolphins were sighted once, while 28% ( n = 31) were sighted five or more times. Nineteen percent ( n = 21) of identified dolphins were determined to be year-round residents; eight percent ( n = 9) seasonal residents. The majority (64%, n = 72) of identified dolphins were sighted in the study area during a single season or in two consecutive seasons and were classified as transients. This study documents the northernmost known site of a resident bottlenose dolphin community on the east coast of the United States, suggesting a complex bottlenose dolphin stock structure.     

Historical U.S. Residential Coal Use and Female Lung Cancer Mortality

Recent ecological and case-control studies have indicated elevated lung cancer mortality (LCM) associated with bituminous “smoky” coal (BC) use in China, but no similar study has been conducted using U.S. populations. Early-to-mid 20^th century U.S. county-level consumption of BC for home heating was examined in relation to age-specific LCM, focusing on mortality in white women aged 40+ vs. 60+ years (among whom ～11% vs. ～5% ever smoked, respectively) during 1950 to 1954. To limit potential confounding due to variations in housing characteristics associated with counties where most vs. few homes used coal for heating, this study focused on domestic BC consumption only in 640 counties in which >75% of homes used coal for heating in 1940. County-level data on domestic net tons of BC consumed per capita for the year 1918 were used to estimate lifetime residential exposure to BC smoke, and analyses focused on a 539-county subset for which estimated BC use remained fairly constant between 1918 and 1940. Significantly positive ecological associations were found between BC use and LCM risk in U.S. white women dying in 1950 to 1954 at age 40+ or 60+ y, after adjusting for age and combinations of 20 socio-demographic/geoclimatic variates. The apparent associations suggest that lifetime exposure to residential BC-combustion smoke may have increased LCM risk by about 25% to 50% among relatively highly exposed U.S. women. While these results must viewed in the context of the inherent limitations of any ecological study design, their consistency with results from studies on Chinese women suggests that some risk reduction might be achieved by increased (or universal) application of inexpensive measures to reduce or eliminate any indoor coal smoke in U.S. homes.     

Evidence of predatory control of yellow perch (Perca flavescens) recruitment in Lake Erie, U.S.A.

Predation can be a major factor in recruitment success of yellow perch ( Perca flavescens Mitchitl). Trawl catches of age-0 yellow perch in western Lake Erie declined from 870·3 per trawling h in June to 3·3 per trawling h in late July 1988. Coincident with the decline in relative abundance of age-0 yellow perch we found large numbers of age-0 yellow perch in the stomachs of small walleyes ( Stizostedion vitreum Mitchill). From this evidence we hypothesized that predation by walleyes may have caused the demise of the 1988 year-class of yellow perch. We used a population and bioenergetics modelling approach to estimate the impact of walleye predation on the abundance of age-0 yellow perch. Modelling showed that 6·8 × 10⁹ age-0 yellow perch that had attained 18 mm total length ( t.l. ), were eaten by small (age-2 and younger) walleye from June through July 1988. We estimated that walleye ate 28·4–89·7% of the yellow perch reaching 18 mm t.l. during 1988. The majority of this predation (77% of total) was by the abundant age-2 cohort of walleyes. We concluded that, even in a large system such as Lake Erie, predation can play a major role in structuring year-class strength of yellow perch and, thus, management of percid fisheries should be conducted on a fish-community basis.     

Tributyltin in U.S. Market-Bought Seafood and Assessment of Human Health Risks

This study assessed potential human health risks posed by tributyltin in seafood purchased from U.S. seafood markets. In 1989 and 1990, samples of fish, bivalve molluscs and crustacea were purchased at local markets along the Atlantic, Gulf and Pacific coasts of the United States and along the Great Lakes (Lake Michigan). Samples were then analyzed for tributyltin, and the concentrations observed used to evaluate potential human health risks from consumption of market-bought seafood on the basis of available mammalian toxicology data. The assessment indicated health effects were unlikely from exposure to tributyltin in market-bought seafood during 1989 to 1990, shortly after peak tributyltin usage in antifoulant bottom paints on vessels in the United States.     

The Use and Perception of Electronic Cigarettes and Snus among the U.S. Population

Background

E-cigarettes have generated controversy in the tobacco control field similar to that of Swedish snus, which came to the U.S. market six years earlier. Some argue that e-cigarettes have great potential to help smokers quit regular cigarettes while others contend they should be banned for lack of safety and efficacy data. This study examined population data from the U.S.

Methods

A U.S. population survey with a national probability sample (N=10,041) was conducted (February 24 to March 8, 2012, before any major paid advertisement of e-cigarettes appeared on television). Survey respondents were asked if they had heard about e-cigarettes, where they had heard about them, whether they had used e-cigarettes or snus, how often they used them, and why they used them. Responses were weighted to represent the entire U.S. population.

Findings

A high proportion, 75.4%, reported having heard about e-cigarettes. Television ranked as the number one source of information, followed by “in-person conversation” and “Internet.” About 8.1% had tried e-cigarettes, and 1.4% were current users. These rates were twice those of snus (4.3% and 0.8%, respectively). Among current smokers, 32.2% had tried e-cigarettes, and 6.3% were current users. Over 80% of current e-cigarette users were non-daily users. Women were significantly more likely to have tried e-cigarettes than men. Those who had tried e-cigarettes were more likely than those who tried snus to report their products being safer than regular cigarettes (49.9% vs. 10.8%). Almost half (49.5%) of current smokers were susceptible to using e-cigarettes in the future.

Conclusions

That e-cigarettes have surpassed snus in adoption rate, even before any promotion by major tobacco companies, suggests that the former have tapped into smokers’ intuitive preference for potentially harm-reducing products, probably due to the product design. E-cigarette use is likely to increase in the next few years.     

Resource utilization by bull char and cutthroat trout in a mountain stream in Montana,U.S.A.

Resource utilization of sympatric populations of bull char,Salvelinus confluentus, and west-slope cutthroat trout,Oncorhynchus clarki lewisi, were studied by underwater observations of foraging behaviour and microhabitat use, and dietary analysis in a mountain stream of the Flathead River Basin, northwest Montana, U.S.A. Nearly 70% of bull char were categorized as benthic foragers, which moved constantly and captured prey primarily from the streambed, while all cutthroat trout were drift foragers, which held relatively fixed focal points in the midwater layers of pools during foraging. The composition of stomach contents was markedly different between the two species. Bull char fed primarily on baetid mayflies captured from the benthos or drift, whereas cutthroat trout ate primarily terrestrial invertebrates. The species also used different microhabitats. Bull char held positions close to the streambed and rarely strayed far from overhead cover, whereas cutthroat trout held focal points farther above the bed and far from overhead cover. Dietary segregation between these two salmonids appeared to result not only from differences in foraging tactics but also in the foraging microhabitats. Resource partitioning is considered to be one of important mechanisms allowing coexistence of these two stream salmonids.     

Dynamics of Material and Energy Use in U.S. Pulp and Paper Manufacturing

This article presents a dynamic computer model of US. pulp and paper production to facilitate organization of diverse industry data and to investigate the industry's likely material and energy use in the future. A set of probable scenarios of growth in paper and paperboard production, wastepaper utilization rates, and diffusion of technologies within the industry is used to assess the realm of material and energy use profiles for the period 1988-2020.
Several conclusions emerge from this study. First, stabilizing or reducing total energy consumption in pulp and paper production, in combination with moderate production growth, quires that future annual increases in energy efficiency must be almost twice as high as the efficiency improvements achieved for the period 1972-1992. Second, to maintain or increase the industry's use of biomass fuels depends on one or a combination of different approaches, such as rapid dissemination of energy-saving technology or reduction in the rate of growth of wastepaper utilization. Third, increased wastepaper utilization rates lead to a significant replacement of pulpwood by recycled fiber. Yet toyal pulpwood consumption continues to increase to satisr) the requirements of increased paper and paperboard produdion, even under the assumption that the wastepaper utilization rate passes 50% and wastepaper utilization triples by the year 2020     

Size and age estimates at sexual maturity for the little skate Leucoraja erinacea from the western Gulf of Maine,U.S.A.

Size and age estimates at sexual maturity were determined for 162 male and 273 female little skates Leucoraja erinacea collected from the western Gulf of Maine. Maturity ogives suggest that 50% maturity in females occurs at age 9·5 years and 480 mm total length (L_T), whereas 50% maturity in males occurs at a slightly younger age of 7·7 years and smaller size of 460 mm L_T. Age estimates were made from 389 L. erinacea ranging in size from 93 to 570 mm L_T. The index of average per cent error and age‐bias plots indicated that the ageing methods were precise and non‐biased. Additionally, annual periodicity of band formation was validated with oxytetracycline in eight individuals (three males and five females) ranging in age from 3 to 12 years. In conclusion, results from this study indicate that L. erinacea exhibits characteristics that make other elasmobranch populations highly susceptible to overexploitation.     

Comparison of U.S. and Japanese Consumers’ Perceptions of Remanufactured Auto Parts

This study compares U.S. and Japanese consumers’ perceptions of remanufactured auto parts. Remanufactured parts have a long history and enjoy continuing success in the U.S. domestic aftermarket. In contrast, although Japan's domestic aftermarket is growing, it remains comparatively underdeveloped. This research examines whether customers’ perceptions of remanufactured products explain their lower acceptance in Japan. Our Internet survey of 440 U.S. and 300 Japanese respondents examined their knowledge of remanufactured auto parts, perceptions of their benefits and risks, and price consciousness. The results reveal that Japanese consumers know less about remanufactured products, perceiving them as entailing lower benefits and greater risk, especially concerning quality, and are less price conscious. Drawing on its results, this study suggests measures to promote markets for remanufactured auto parts in Japan and in economies in which such markets are in an early stage of development.     

Race,self-interest and privilege amongst students at elite U.S. and U.K. universities

Warikoo’s The Diversity Bargain describes the findings of research which explores how students at elite universities in the U.S. and the U.K. conceptualize race in relation to the admissions process and their experiences on campus. This is an important study, which reveals differences in the degree of comfort and caution displayed by white students in their framing of race. There are three areas worthy of further exploration: the subjective positioning of the author herself as she engages and responds to the research findings; the advantages of affording a richer theoretical framework to the analysis and, finally, the similarities between Warikoo’s notion of a diversity bargain and Derrick Bell’s concept of interest convergence. These are explored in turn.     

Stream Restoration in the Upper Midwest, U.S.A.

Restoration activities intended to improve the condition of streams and rivers are widespread throughout the Upper Midwest, U.S.A. As with other regions, however, little information exists regarding types of activities and their effectiveness. We developed a database of 1,345 stream restoration projects implemented from the years 1970 to 2004 for the states of Michigan, Ohio, and Wisconsin in order to analyze regional trends in goals, presence of monitoring, spatial distribution, size, and cost of river restoration projects. We found that data on individual projects were fragmented across multiple federal, state, and county agencies, as well as nonprofit groups and consulting firms. The most common restoration goals reported for this region were in‐stream habitat improvement, bank stabilization, water‐quality management, and dam removal. The former two were most common in Michigan and Wisconsin, where salmonid fisheries enhancement appeared to be an important concern, whereas water‐quality management was most frequent in Ohio. The most common restoration activities were the use of sand traps and riprap, and other common activities were related to the improvement of fish habitat. The median cost was $12,957 for projects with cost data, and total expenditures since 1990 were estimated at $444 million. Over time, the cost of individual projects has increased, whereas the median size has decreased, suggesting that restoration resources are being spent on smaller, more localized, and more expensive projects. Only 11% of data records indicated that monitoring was performed, and more expensive projects were more likely to be monitored. Standardization of monitoring and record keeping and dissemination of findings are urgently needed to ensure that dollars are well spent and restoration effectiveness is maximized.     

Sedentary Behavior,Physical Activity,and the Metabolic Syndrome among U.S. Adults

Objective: We examined the associations among physical activity, sedentary behavior, and metabolic syndrome in a representative sample of U.S. adults. Research Methods and Procedures: A total of 1626 men and women ≥20 years old from National Health and Nutrition Examination Survey 1999 to 2000 who attended the morning examination were evaluated. The metabolic syndrome was defined by using the definition from the National Cholesterol Education Program. Results: In unadjusted analysis, participants who did not engage in any moderate or vigorous physical activity during leisure time had almost twice the odds of having metabolic syndrome [odds ratio (OR), 1.90; 95% confidence interval (CI), 1.22 to 2.97] as those who reportedly engaged in ≥150 min/wk of such activity. Adjustment for age, sex, race or ethnicity, educational status, smoking status, and alcohol use attenuated the OR (OR, 1.46; 95% CI, 0.87 to 2.45). Compared with participants who watched television or videos or used a computer <1 h/d outside of work, the adjusted ORs for having metabolic syndrome were 1.41 (95% CI 0.80 to 2.51) for 1 h/d, 1.37 (95% CI 0.85 to 2.20) for 2 h/d, 1.70 (95% CI 0.92 to 3.14) for 3 h/d, and 2.10 (95% CI 1.27 to 3.47) for ≥4 h/d. Additional adjustment for physical activity or sedentary behavior minimally affected the ORs. Discussion: Sedentary behavior is an important potential determinant of the prevalence of the syndrome. Efforts to lessen the amount of time that U.S. adults spend watching television or videos or using a computer, especially if coupled to increases in physical activity, could result in substantial decreases in the prevalence of metabolic syndrome.     

High income men have high value as long-term mates in the U.S.: personal income and the probability of marriage,divorce, and childbearing in the U.S.

Using data from the first Census data set that includes complete measures of male biological fertility for a large-scale probability sample of the U.S. population (the 2014 wave of the Study of Income and Program Participation-N = 55,281), this study shows that high income men are more likely to marry, are less likely to divorce, if divorced are more likely to remarry, and are less likely to be childless than low income men. Men who remarry marry relatively younger women than other men, on average, although this does not vary by personal income. For men who divorce who have children, high income is not associated with an increased probability of having children with new partners. Income is not associated with the probability of marriage for women and is positively associated with the probability of divorce. High income women are less likely to remarry after divorce and more likely to be childless than low income women. For women who divorce who have children, high income is associated with a lower chance of having children with new partners, although the relationship is curvilinear. These results are behavioral evidence that women are more likely than men to prioritize earning capabilities in a long-term mate and suggest that high income men have high value as long-term mates in the U.S.