pH and hydrogen ion deposition patterns in precipitation for the continental United States and Canada     

Joe Wisniewski  John D. Kinsman 《Water, air, and soil pollution》1988,38(1-2):1-17

Maps of both volume-weighted mean pH and mean H⁺ deposition in precipitation were developed for the continental United States and Canada using data from 12 precipitation chemistry monitoring networks. The maps were constructed using 1981–1982 laboratory pH data from approximately 130 monitoring sites. The area of greatest acidity (lowest pH/highest H⁺ deposition) is located in the northern Ohio Valley and southeastern Ontario, an area corresponding to high SO_x and NO_x emissions.  相似文献   

Acid rain deposition patterns in the continental United States     

Joe Wisniewski  Edwin L. Keitz 《Water, air, and soil pollution》1983,19(4):327-339

Acid rain has become a major environmental concern, the current extent of which is illustrated in this paper. Maps of both pH and H⁺ deposition in precipitation have been developed for the continental United States by analyzing laboratory pH data from nine precipitation chemistry networks and two single stations spread across the continental United States and southern Canada during the late 1970's. Average laboratory pH values were obtained or calculated for approximately 100 stations, and isopleths of weighted mean pH and mean annual H+ deposition in precipitation were drawn. Results of this analysis show that in spite of a wide variety of collection methods and sampling intervals, there is remarkable uniformity in the average pH among the various stations. The northeastern United States continues to exhibit the most acidic precipitation, with remaining portions of the eastern United States, states along the western coastline and a pocket in central Colorado also experiencing acid precipitation.  相似文献   

Ethyl carbamate levels in selected fermented foods and beverages     

B J Canas  D C Havery  L R Robinson  M P Sullivan  F L Joe  G W Diachenko 《Journal of the Association of Official Analytical Chemists》1989,72(6):873-876

Ethyl carbamate (EC), also known as urethane, is an animal carcinogen and a by-product of fermentation. Because EC has been found in distilled spirits and wines, a variety of fermented foods and beverages were analyzed to assess its occurrence in other products. Previously described methods using a gas chromatograph-thermal energy analyzer with a nitrogen converter were modified for each matrix and gave recoveries of greater than 80%, with a limit of detection in the 1-2 micrograms/kg (ppb) range. A total of 152 test samples were analyzed; EC levels ranged from none found to 3 ppb in 15 cheeses, 6 teas, 12 yogurts, and 8 ciders; from none found to 13 ppb in 30 breads and 69 malt beverages; and from none found to 84 ppb in 12 soy sauces. Gas chromatography/mass spectrometry/mass spectrometry was used to confirm EC identity and to quantitate EC in selected food extracts.  相似文献   

Future energy options,ethics and a case for conservation     

Joe E. Armstrong 《Water, air, and soil pollution》1977,7(2):187-194

Up to 1990 the U.S. must rely upon four major sources for additional energy to meet the expected continued growth in energy use; (1) expanded coal and the associated synthetics fuels derived from it, (2) expanded production of Continental shelf and Alaskan oil and gas, (3) nuclear, and (4) imported petroleum. After 1990 solar and oil shale could play increasingly important roles as additional sources. These major energy options will be compared at a national level in their broad environmental, economic, social, and political implementation impacts. In view of the disadvantages which all of these choices entail, the necessity to continue energy use growth into the indefinite future will be explored with special emphasis on major effects of economic soundness, employment, food supply, national defense, and the emerging social unrest which characterizes the 1970s in the U.S.A. An inevitable conclusion from the preceeding survey urges that a major energy conservation program would be a wise and prudent course for the U.S.A. to follow, with the stipulation that its gradual implementation over something like a 10 year time period is necessary.  相似文献   

Protein/energy ratios of current diets in developed and developing countries compared with a safe protein/energy ratio: implications for recommended protein and amino acid intakes     

Millward DJ  Jackson AA 《Public health nutrition》2004,7(3):387-405

Revised estimates of protein and amino acid requirements are under discussion by the Food and Agriculture Organization (FAO)/World Health Organizaion (WHO), and have been proposed in a recent report on Dietary Reference Intakes (DRIs) from the USA. The nature and magnitude of these requirements are not entirely resolved, and no consideration has been given to the potential influence of metabolic adaptation on dietary requirements. We have examined the implications of these new values, and of the conceptual metabolic framework in which they are used, for defining the nutritional adequacy of protein intakes in developed and developing countries. We have expressed proposed values for protein requirements in relation to energy requirements, predicted for physical activity levels of 1.5, 1.75 and 2.0 times basal metabolic rate, in order to generate reference ratios for protein energy/total energy (reference P/E ratio) as a function of age, body weight, gender and physical activity level. Proposed values for amino acid requirements have been used to adjust the available digestible P/E ratio of foods and diets for protein quality. Focusing on the diets of UK omnivores and vegetarians and on diets in India, the risk of protein deficiency is evaluated from a comparison of P/E ratios of metabolic requirements with protein-quality-adjusted P/E ratios of intakes. A qualitative and conservative estimate of risk of deficiency is made by comparing the adjusted P/E ratio of the intake with a reference P/E ratio calculated for age, body weight, gender and physical activity according to FAO/WHO/United Nations University. A semi-quantitative estimate of risk of deficiency has also been made by the cut point approach, calculated as the proportion of the intake distribution below the mean P/E ratio of the requirement. Values for the quality-adjusted P/E ratio of the diet range from 0.126 for the UK omnivore diet to 0.054 for a rice-based diet of adults in West Bengal, which is lysine-limited, falling to 0.050 for 1-year-old children. The reference P/E ratio for men and women increases with age, is higher for females than males, is higher for small compared with large adults at any age and decreases with physical activity. Thus if a particular diet is potentially limiting in protein, protein deficiency is most likely in large, elderly sedentary women followed by the adolescent female and least likely in moderately active young children, the opposite of what has usually been assumed. Within the currently accepted framework, the diets do not meet the protein needs of the entire population of the UK, have a significant risk of deficiency throughout India for all except extremely active small adults, and are grossly inadequate for all population groups, apart from physically active young children in West Bengal, regardless of body weight or level of food intake. The lysine limitation of the cereal-based Indian diets is dependent on the choice of lysine requirement values from the published range. We consider that the value selected is too high, because of uncertainties and inconsistencies in the approaches used. A more appropriate choice from the lower end of the range would remove the lysine limitation of cereal-based diets, and reduce some of the perceived risk of deficiency. However, diets remain limited by the amount of digestible protein for many population groups, especially in West Bengal. In the context of risk management, one option would be to accept the current values and the conceptual metabolic framework within which they have been derived. This would have major implications for the supplies of high-quality protein to the developing countries. An alternative option would be to re-evaluate the currently proposed values for the requirements for protein and amino acids. We conclude that the choice of values for the adult lysine requirement should be re-evaluated and that serious consideration should be given to the extent to which adaptive mechanisms might enable the metabolic requirement for protein to be met from current intakes. This will entail a better understanding of the relationships between dietary protein and health.  相似文献   

Natural sinks of CO2 conclusions,key findings and research recommendations from the palmas Del Mar Workshop     

Ariel E. Lugo  Joe Wisniewski 《Water, air, and soil pollution》1992,64(1-2):455-459

This paper documents the conclusion, key findings and research recommendations from the Natural Sinks of CO₂ Workshop held in Palmas Del Mar, Puerto Rico during 24–27 February 1992. Also presented are some preliminary estimates of actual and potential carbon sinks in terrestrial and aquatic ecosystems.  相似文献   

Analytical study of azadirachtin and 3-tigloylazadirachtol residues in foliage and phloem of hardwood tree species by liquid chromatography-electrospray mass spectrometry     

Grimalt S  Thompson DG  Coppens M  Chartrand DT  Shorney T  Meating J  Scarr T 《Journal of agricultural and food chemistry》2011,59(15):8070-8077

A rapid and sensitive LC-ESI-MS method has been developed and validated for the quantitation of azadirachtin and 3-tigloylazadirachtol in deciduous tree matrices. The method involves automated extraction and simultaneous cleanup using an accelerated solvent technique with the matrix dispersed in solid phase over a layer of primary-secondary amine silica. The limits of quantification were 0.02 mg/kg for all matrices with the exception of Norway maple foliage (0.05 mg/kg). Validation at three levels (0.02, 0.1, and 1 mg/kg), demonstrated satisfactory recoveries (71-103%) with relative standard deviation <20%. Two in-source fragment ions were used for confirmation at levels above 0.1 mg/kg. Over a period of several months, quality control analyses showed the technique to be robust and effective in tracking the fate of these natural botanical insecticides following systemic injection into various tree species for control of invasive insect pest species such as the emerald ash borer and Asian longhorned beetle.  相似文献   

Chemopreventive potential of 18beta-glycyrrhetinic acid: an active constituent of liquorice, in 7,12-dimethylbenz(a)anthracene induced hamster buccal pouch carcinogenesis     

Kowsalya R  Vishwanathan P  Manoharan S 《Pakistan journal of biological sciences: PJBS》2011,14(11):619-626

Chemoprevention, a useful and attractive approach in experimental oncology, helps to investigate the cancer preventive potential of natural products and synthetic entities. Present study evaluated the chemopreventive potential of glycyrrhetinic acid in 7,12-dimethylbenz(a)anthracene (DMBA) induced hamster buccal pouch carcinogenesis. Oral tumor was developed in the buccal pouch of golden Syrian hamsters by painting with DMBA three times a week for 14 weeks. The tumor incidence and the status of phase I and phase II detoxification enzymes were assessed in hamsters treated with DMBA alone and DMBA+glycyrrhetinic acid treated hamsters. One hundred percent tumor formations, which were histopathologically confirmed as well-differentiated squamous cell carcinoma, were observed in hamsters treated with DMBA alone. Also, the status of detoxification enzymes were markedly altered in the liver and buccal mucosa of hamsters treated with DMBA alone. Oral administration ofglycyrrhetinic acid at a dose of 45 mg kg(-1) body weight to hamsters treated with DMBA completely prevented the tumor formation as well as restored the status of detoxification enzymes. Present study thus demonstrated the chemopreventive potential of glycyrrhetinic acid in DMBA induced oral carcinogenesis.  相似文献   

Influence of dietary antioxidants and fatty acids on neutrophil mediated bacterial killing and gene expression in healthy Beagles     

Hall JA  Chinn RM  Vorachek WR  Gorman ME  Greitl JL  Joshi DK  Jewell DE 《Veterinary immunology and immunopathology》2011,139(2-4):217-228

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Distraction–Fusion for Caudal Cervical Spondylomyelopathy Using an Intervertebral Cage and Locking Plates in 14 Dogs     

Frank Steffen Dr Med Vet Diplomate ECVN  Katja Voss Dr Med Vet Diplomate ECVS  Joe P. Morgan Prof Dr Med Vet Diplomate ACVR 《Veterinary surgery : VS》2011,40(6):743-752

Objective: To evaluate clinical and radiographic outcome in dogs with caudal cervical spondylomyelopathy (CCSM) treated with an intervertebral fusion cage and locking plates. Study Design: Prospective clinical study. Animals: Large breed dogs (n=14) with CCSM. Methods: Dogs had single level cervical spine distraction/fusion performed using an intervertebral cage with a hollow center filled with cancellous autograft and 2 ventrally applied locking plates. Outcome was measured using neurologic scores and radiographic interpretation 6 weeks, 6 months, and 12 months postoperatively. Results: The surgical procedure was well tolerated in all dogs. Final outcome at 12 months was available in 9 dogs. Five dogs were judged excellent, 1 dog was good, 2 dogs were satisfactory, and 2 dogs were poor because of adjacent segment disease. Four dogs died for reasons unrelated to the procedure. Radiographically, implants remained stable over the entire follow‐up period. The disc space continued to fill with an immature pattern of new bone, which showed progressive increase in opacity and quantity. Subsidence of the cage (median 2 mm) was detected in 9 dogs at 6 weeks and remained unchanged in those that could be followed further. Conclusion: Distraction–fusion of single level CCSM in dogs with a combination of intervertebral cage and ventral locking plates is clinically effective and results in successful bony fusion.  相似文献