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PubMed2006

Evaluation of the economic and environmental impact of converting cropland to forest: a case study in Dunhua county, China.

The Sloping Land Conversion Program (also known as "Grain for Green" or the Upland Conversion Program) for converting cropland to forest is one of China's most ambitious environmental initiatives, and is one of the world's largest land-conservation programs with a budget of RMB 337 billion (over US$ 40 billion). Although environmental impacts have played a vital role in the general reasoning and argumentation for forest plantations, environmental impact analyses have often received less attention than economic analyses in the planning of plantation forestry projects. The overall goal of this paper is to evaluate the program's environmental impact considering the farmer's interests and the potential social benefits due to carbon sequestration in different scenarios based on household and field survey data in Dunhua County. Our findings are that: (1) in many cases, the program did not give adequate consideration to land productivity and environmental heterogeneity when selecting plots; (2) more than half of the reforestation plots were on flat cropland (slopes of less than 5 degrees ); (3) in five of the eight townships, net incomes on reforested land were substantially above or below previous crop incomes, raising questions about the efficiency of the allocation of compensation to farmers participating in the program; (4) the potential carbon co-benefit increased the NPV of the program by 5954-7009 RMB/ha. In conclusion, we recommend that more attention should be paid to the quality of reforestation programs rather than just their scale and note that consideration of potential carbon sequestration co-benefits enhances the benefits of cropland conversion programs.

Carbon↗

PubMedDate not supplied

Selection of relevant non-target herbivores for monitoring the environmental effects of Bt maize pollen.

Genes of Bacillus thuringiensis var. kurstaki (Berliner) that encode lepidopteran-specific toxins were engineered into maize for protection against the European Corn Borer, Ostrinia nubilalis (Hbn.). Recent data suggest that Lepidoptera may be negatively affected, if maize pollen contains high amounts of Bt toxin and is diposited on host plants near maize fields. Monitoring the environmental effects of commercial Bt maize fields requires effective use of limited financial and logistical resources. The aim of this study was to develop and apply tools for selecting relevant herbivore species for the field monitoring of environmental Bt toxin effects via pollen deposition. We first present a theoretical selection tree based on "risk index of Bt pollen for herbivores" (I(Btp)). Our index consists of five classes from zero (not relevant) to four (highly relevant) derived from data on potential temporal and spatial coincidence of pollen exposure (A), feeding mode (B), susceptibility to lepidopteran-specific Bt toxins (C) and hazard to rare and/or endangered species ("Red List") (D). We then screened the Macrolepidoptera database LEPIDAT to identify relevant species in Germany. Finally, we also applied the index to species found in a local biocoenotic field study (Bonn, Western Rhineland, Germany). Approximately 7% of the German Macrolepidoptera species mainly occur in farmland areas and were selected as being potentially affected by Bt pollen exposure. Of these species, 14% (= 1% of total) were found to be potentially exposed on a regional scale. The combination of I(Btp) and database screening enables us to pre-select species for monitoring purposes.

Animals↗

PubMed2000

Persistence of selected Spartina alterniflora rhizoplane diazotrophs exposed to natural and manipulated environmental variability.

Rhizoplane-rhizosphere nitrogen-fixing microorganisms (diazotrophs) are thought to provide a major source of biologically available nitrogen in salt marshes dominated by Spartina alterniflora. Compositional and functional stability has been demonstrated for this important functional group; however, the quantitative responses of specific diazotroph populations to environmental variability have not been assessed. Changes in the relative abundances of selected rhizoplane diazotrophs in response to long-term fertilization were monitored quantitatively by reverse sample genome probing. Fertilization stimulated Spartina, with plant height nearly tripling after 1 year. Fertilization also resulted in significant changes in interstitial porewater parameters. Diazotrophic activity (acetylene reduction assay) was sensitive to the fertilization treatments and was inhibited in some plots on several sampling dates. However, inhibition was never consistent across all of the replicates within a treatment and activity always recovered. The rhizoplane diazotrophs were quite responsive to environmental variability and to experimental treatments, but none were displaced by either environmental variability or experimental treatments. All strains were detected consistently throughout this study, and extensive spatial heterogeneity in the distribution patterns of these organisms was observed. The physiological traits that differentiate the diazotroph populations presumably support competitiveness and niche specialization, resulting in the observed resilience of the diazotroph populations in the rhizosphere.

Acetylene↗

PubMed2003

Prioritisation of veterinary medicines in the UK environment.

A wide range of veterinary medicines is used to treat animals in the UK. Whilst the environmental impact of selected substances (particulary the sheep dip chemicals, anthelmintics and fish farm chemicals) has been well studied, limited information is available in the public domain on the other groups of substances (e.g. antifungals, coccidiostats, antiprotozoals, hormones and growth promoters). There is therefore a need to identify other substances that may impact the environment in order to design national monitoring programmes, target experimental work and develop pollution prevention methodologies. In this study, a simple two-stage prioritisation scheme was developed and applied to veterinary medicines in use in the UK. In the first stage, those substances that have high potential to enter the environment in significant amounts were identified on the basis of amounts used in the UK, treatment type and metabolism. In stage 2, the hazard of the identified substances to terrestrial and aquatic organisms was assessed. Using the approach, a total of 56 substances or groups were assigned to a 'high priority' category. For eleven of these substances, sufficient data were available to characterise their risk, these were: oxytetracycline, chlortetracycline, tetracycline, sulphadiazine, amoxicillin, diazinon, tylosin, dihydrostreptomycin, apramycin, cypermethrin and sarafloxicin. For the remaining 45 substances, full datasets were not available and it is recommended that in the first instance, attempts are made to fill these data gaps.

Environmental Exposure↗

PubMed2003

NMR and molecular modeling in environmental chemistry: prediction of 13C chemical shifts in selected C10-chloroterpenes employing DFT/GIAO theory.

Accurate predictions of 13C NMR chemical shifts (standard error approximately 1.7 ppm) are achieved for a subset of chlorinated bornanes by empirical scaling of shifts from GIAO calculations with geometries obtained from HF/6-31G* calculations. The optimized molecular geometries were compared with X-ray structures for three of the toxaphene components most frequently detected in environmental samples (Parlar nos. 26, 50 and 62), and the concordance between the experimental and calculated values was found to be satisfactory. Taken overall, the results indicate that theoretical methods hold great promise for rationalizing 13C NMR chemical shifts in organohalogen compounds. However, it appeared that the DFT/GIAO shifts need to be empirically scaled to achieve good numerical agreement with experimental shifts in chlorinated bornanes. Obviously, there is a need to develop new computational methods to describe the large deshielding effects of chlorine atoms properly.

Camphanes↗

PubMed2001

Selection bias and confounding in case-crossover analyses of environmental time-series data.

The case-crossover study design is a popular analytic tool for estimating the effects of triggers of acute outcomes by environmental exposures. Although this approach controls for time-invariant confounders by design, it may allow for selection bias and confounding by time-varying factors. We conducted a simulation study of the sensitivity of the symmetric bidirectional case-crossover design to time-varying patterns in exposure and outcome. We identified the effects of selection bias and confounding on symmetric bidirectional case-crossover results and offer strategies to eliminate or reduce these biases. Selection bias results when exposure in the reference periods is not identically representative of exposure in the hazard periods, even when the distribution of exposure is stationary. This bias can be estimated and removed. Selection bias also occurs when the distribution of exposure is nonstationary, but the adjusted symmetric bidirectional case-crossover methodology substantially controls for this. Confounding results from a common temporal pattern in the exposure and the outcome time series, but can also be the result of patterns in exposure and outcome that, although asymptotically uncorrelated, are correlated at finite series lengths. All three biases are reduced by choosing shorter referent-spacing lengths. This effect is illustrated using data on air pollution and daily deaths in Chicago.

Air Pollution↗

PubMed1988

Critical control points for foods prepared in households whose members had either alleged typhoid fever or diarrhea.

Hazard analysis of food preparation practices were conducted in four households and eleven others were visited to survey both food preparation practices and environmental conditions. Households selected had members who were suffering from either diarrhea of unknown etiology or alleged typhoid fever. Hazard analyses and sanitary surveys included gathering data on time-temperature exposures of foods, collecting samples of food and drinking water, sampling sewage or drains, and obtaining stool specimens from persons with diarrhea and from family controls. Food samples were tested for aerobic mesophilic colony counts and common foodborne pathogens; specimens were tested for Salmonella, Shigella, Campylobacter and Yersinia. Campylobacter was isolated from two persons purported to have diarrhea, but neither Salmonella, Shigella nor Yersinia were recovered from alleged cases or controls. Salmonella agona was recovered from a latrine. Most foods were cooked to internal temperatures to or near to boiling. Those not promptly eaten were held at ambient room or outside temperatures until a subsequent meal, until a family member returned home, or until lunch time when taken to the fields. During these intervals, microorganisms multiplied and mesophilic aerobic organisms increased often reaching 10(8)/g or greater before consumption. None of these foods were reheated before eating. Bacillus cereus was isolated from 4 of 10 samples; one sample of 'moro' (beans and rice) exceeded 10(6)/g, two other samples exceeded 10(3)/g. Staphylococcus aureus was isolated from 7 of 14 samples, one exceeded 10(5)/g. Fecal coliforms were isolated from 8 of 14 food samples, five exceeded 10(5)/g. Neither Salmonella nor Shigella were isolated from any food, the community water supplies or from vessels of water within houses. Fecal coliform counts of water were less than 3/ml, except one sample from a clay vessel (9/ml). Risks associated with cooked foods which were not promptly eaten appeared to be greater than that associated with water.

Adolescent↗

PubMed1999

Determination of surfactants by capillary electrophoresis.

Capillary electrophoresis has been increasingly used during the past few years for the separation and determination of surfactants. These substances are applied in many household and industrial products such as laundry detergents, cosmetics and pharmaceuticals, often as homologous and isomeric mixtures. Product development and control as well as toxicological and environmental analyses require selective and sensitive analytical methods. This review presents capillary electrophoretic techniques to determine important representatives of cationic, anionic, and neutral surfactants. The application of different buffer additives such as organic solvents, cyclodextrins or micelles to enhance the resolution of complex mixtures is discussed. Besides direct and indirect UV and fluorescence detection, examples for conductivity and mass spectrometric detection are also given. Derivatization procedures to improve the detectability and implement charge in neutral analytes are described. The successful use of capillary electrophoresis for surfactant determinations has proven that it can serve as a routine technique in many real-world applications. Robust, validated methods for the quantitation of single compounds, such as alkylbenzene sulfonates, sodium dodecyl sulfate and benzalkonium salts, are now available. Characteristic peak patterns (fingerprint analysis) can be used for the identification of surfactants in multicomponent formulations (e.g. ethoxylates and phosphonates).

Anions↗

PubMed1987

Gastric carcinoma in patients younger than age 36 years.

The clinical and pathologic features of 18 patients with gastric carcinoma younger than age 36 years were studied. Of these patients, 36.8% were Hispanics of Mexican origin. Eighteen percent of the Mexican population with gastric carcinoma were younger than 36 years as compared to 2.8% of the overall population (P less than 0.05). Fifty percent of the gastric ulcers in the Mexican population were malignant as compared to 6% in the non-Mexican population (P less than 0.05). In addition, a subset of aggressive carcinomas were found. Patients presenting with symptoms of less than 6 months' duration had a survival of less than 6 months, compared to the less aggressive subset, in which patients had symptoms for greater than 6 months and survived longer than 6 months. Racial, environmental influences, or selection bias may account for the differences in gastric carcinoma in the Mexican and non-Mexican population. Factors contributing to a more aggressive form of carcinoma are unclear and require further study.

Adult↗

PubMed2000

Interactions of phosphatidylinositol 3-kinase Src homology 3 domain with its ligand peptide studied by absorption, circular dichroism, and UV resonance raman spectroscopies.

Absorption, circular dichroism (CD), and UV resonance Raman (UVRR) spectroscopies were applied to selectively examine the environmental and structural changes of Trp and Tyr residues in the phosphatidylinositol 3-kinase (PI3K) SH3 domain induced by ligand association. Comparison of the spectra of PI3K SH3 in the presence or absence of its ligand peptide RLP1 (RKLPPRPSK) indicated that RLP1 binding changed the environment of Trp55 of the SH3 to be more hydrophilic and its H bonding weaker and that of Tyr residues to be more hydrophobic. The D21N mutant (Asp21 --> Asn) of the SH3 yielded a UV CD distinct from that of the wild type, and its spectral changes induced by RLP1 binding were smaller and different from those of the wild type in absorption, CD, and UVRR spectra, suggesting that the mutation of conserved Asp21 affected the conformation of the ligand binding cleft and thus might lead to the decrease in the ligand affinity. These data provide direct evidence for the occurrence of environmental and structural changes of PI3K SH3 by the association of a ligand and the D21N mutation.

Absorption↗

PubMed1978

The familial component in longevity--a study of offspring of nonagenarians: III. Intrafamilial studies.

The effect of parental longevity on the length of survival of offspring has been examined according to selected demographic and environmental characteristics. The present study is based on 7,103 progeny, 20 years old or older. They were the sons and daughters of 1,766 men or women, 90 or more years old, who were alive in 1922-1930 at the time of ascertainment. The age at death of the other parent of the offspring is the basis of classification used in this analysis. A positive relationship was found between age at death of the non-proband parent and the age at death of the offspring. This relationship existed regardless of similarities or differences in the characteristics analyzed.

Adult↗

PubMed2004

Olfactory fossa of Tremacebus harringtoni (platyrrhini, early Miocene, Sacanana, Argentina): implications for activity pattern.

CT imaging was undertaken on the skull of approximately 20-Myr-old Miocene Tremacebus harringtoni. Here we report our observations on the relative size of the olfactory fossa and its implications for the behavior of Tremacebus. The endocranial surface of Tremacebus is incomplete, making precise estimate of brain size and olfactory fossa size imprecise. However, olfactory fossa breadth and maximum endocranial breadth measured from CT images of one catarrhine species and eight platyrrhine species for which volumes of the olfactory bulb and brain are known show that the osteological proxies give a reasonably accurate indication of relative olfactory bulb size. Nocturnal Aotus has the largest relative olfactory fossa breadth and the largest olfactory bulb volume compared to brain volume among extant anthropoids. Tremacebus had a much smaller olfactory fossa breadth and, by inference, bulb volume--within the range of our sample of diurnal anthropoids. Variations in the relative size of the olfactory bulbs in platyrrhines appear to relate to the importance of olfaction in daily behaviors. Aotus has the largest olfactory bulbs among platyrrhines and relies more on olfactory cues when foraging than Cebus, Callicebus, or Saguinus. As in other examples of nocturnal versus diurnal primates, nocturnality may have been the environmental factor that selected for this difference in Aotus, although communication and other behaviors are also likely to select for olfactory variation in diurnal anthropoids. Considering the olfactory fossa size of Tremacebus, olfactory ability of this Miocene monkey was probably not as sensitive as in Aotus and counts against the hypothesis that Tremacebus was nocturnal. This finding accords well with previous observations that the orbits of Tremacebus are not as large as nocturnal Aotus.

Adaptation, Physiological↗

PubMed2004

Optimization of quadrupole ion storage mass spectrometric conditions for the analysis of selected polybrominated diphenyl ethers. Comparative approach with negative chemical ionization and electron impact mass spectrometry.

Gas chromatography coupled to quadrupole ion storage mass spectrometry (QISTMS) operating in the non-resonant mode is presented as an innovative approach for the analysis of selected polybrominated diphenyl ethers (PBDEs). Although reductions in complexity and time needed for optimization are achieved in comparison with the resonant option, precise adjustment of the mass spectrometric conditions is required. Differences in isolation and fragmentation patterns of target species with degree of bromination were observed. The reliability of the method was confirmed by using standard solutions through the evaluation of certain quality parameters such as accuracy (92-108%), injection repeatability and reproducibility (coefficient of variation below 10% and 15%, respectively). Detection limits ranged from 62 to 621 fg, providing sensitivity similar to that of negative chemical ionisation (NCIMS) and greater than that of electron ionization mass spectrometry. The applicability of QISTMS method to real samples and matrix effects were evaluated through the analysis of some PBDE congeners in a sewage sludge sample from a Spanish waste-water treatment plant. Comparable results were obtained using QISTMS and NCIMS. According to these observations, QISTMS performed in the non-resonant mode may constitute a low-cost, rapid and reliable alternative to high-resolution devices for the analysis of selected PBDEs in environmental samples.

Environmental Health↗

PubMed2003

Familial influence on parkinsonism in a rural area of Turkey (Kizilcaboluk-Denizli): a community-based case-control study.

This population-based study on parkinsonism in a genetically isolated community from a rural area of Turkey aimed to provide a selective evaluation of environmental and heritable risk factors. An increased prevalence of parkinsonism (4.1%) was detected in the village of Kizilcaboluk for people 65 years of age and older. This study included 36 patients with parkinsonism living in Kizilcaboluk and three times that number of age- and sex-matched people serving as controls. A questionnaire including demographic data, family history, education, occupation, data on exposures to pesticides, smoking, alcohol intake, and head trauma was administered. We found a significant association of parkinsonism cases with a positive family history in first-degree relatives (odds ratio [OR], 7.48; 95% confidence interval [CI], 2.52-22.17; P < 0.0001) and with pesticide exposure (OR, 2.96; 95% CI, 1.31-6.69; P = 0.015) compared to the control subjects. The value of genetically isolated populations for the identification of genetic risk factors for common and complex disorders has gained much attention recently because the genetic make-up of these populations is likely to be less complex than that of the general population and our findings should prompt investigations to the nature of a familial aggregation of parkinsonism in this population.

Aged↗

PubMed1990

Self-care agency as a function of patient-environmental factors among nursing home residents.

The relationship between environmental and personal factors on self-appraised self-care agency of nursing home residents was examined. Data were collected from 83 nursing home residents in relation to self-care abilities, environmental constraints, and selected demographic factors. Race and previous occupation were related to self-care agency with residents who were black or previously self-employed evidencing higher scores. In addition, residents who viewed the home as overly restrictive or fostering dependence had lower perceptions of their self-care abilities. The results are discussed in terms of Orem's theory of self-care, social learning theory, and implications for restructuring care within nursing homes.

Aged↗

PubMed2002

Regulatory implications of using constructed wetlands to treat selenium-laden wastewater.

The practice of using constructed wetlands to treat selenium-laden wastewater is gaining popularity in the United States and elsewhere. However, proponents of treatment wetlands often overlook important ecological liabilities and regulatory implications when developing new methods and applications. Their research studies typically seek to answer a basic performance question--are treatment wetlands effective in improving water quality--rather than answering an implicit safety question-are they hazardous to wildlife. Nevertheless, wetland owners are responsible for both the operational performance of treatment wetlands and the health of animals that use them. This is true even if wetlands were not created with the intent of providing wildlife habitat; the owner is still legally responsible for toxic hazards. If poisoning of fish and wildlife occurs, the owner can be prosecuted under a variety of federal and state laws, for example, the Migratory Bird Treaty Act and the Endangered Species Act. In considering this type of treatment technology it is important to document the selenium content of the wastewater, understand how it cycles and accumulates in the environment, and evaluate the threat it may pose to fish and wildlife before deciding whether or not to proceed with construction. Many of the potential hazards may not be obvious to project planners, particularly if there is no expressed intention for the wetland to provide wildlife habitat. Ecological risk assessment provides an approach to characterizing proposed treatment wetlands with respect to wildlife use, selenium contamination, and possible biological impacts. Proper application of this approach can reveal potential problems and the associated liabilities, and form the basis for selection of an environmentally sound treatment option.

Animals↗

PubMed2001

Genes, environment, and exercise.

The definition of the term "environment" has broadened in the past 40 years to include knowledge generated from sequencing genes. Studies on animal responses to the environment have expanded to include selective lifestyle behaviors. Environmental lifestyle components interact with susceptibility genes to pass a threshold of biological significance such that a disease requires clinical treatment. Examples of environmental-gene interactions producing cystic fibrosis and asthma are described. The contributing role of physical inactivity to the epidemic of type 2 diabetes is presented with some of its underlying effectors. A lack of contractile activity by skeletal muscle is associated with less GLUT4 protein in the sarcolemma and a lower glucose uptake into the muscle. The pathways by which contractile activity signals an increase in glucose uptake differs from insulin signaling, but is remarkably similar to how hypoxia stimulates muscle to increase its glucose uptake.

Altitude↗

PubMed1990

Neurotransmitters and stress.

In this article definitions of stress and distress are proposed and the relationships between stress and activities of neurohormonal systems explored. The idea is developed that stress is a condition where expectations--whether genetically programmed, established by prior learning, or deduced from circumstances--do not match the current or anticipated perceptions of the internal or external environment, and this discrepancy between what is observed or sensed and what is expected or programmed elicits patterned, compensatory responses. Distress is viewed here as a form of stress characterized by specific behavioral and autonomic communicated signs, pituitary-adrenocortical and sympathoadrenomedullary activation, and a negative experience that motivates escape or avoidance. During stress, many body systems--including the sympathoadrenal, parasympathetic, and hormonal homeostatic systems--are activated or inhibited in primitively specific patterns regulated by physiological, biochemical, and psychological homeostats. Many of these patterns, which are at least partly inherited, can be understood teleologically on the basis of preservation of the internal environmental and natural selection in evolution.

Animals↗