Impacts of Air Pollution Control Strategies in Kentucky

The purpose of this paper is to estimate the impacts of air pollution control strategies for one state, Kentucky, on its own economy. Effects of the Clean Air Act are estimated, but the emphasis is on scenarios for compliance with pending acid rain legislation. The most restrictive scenario involves a 478,000 ton per year reduction in SO₂. Based on elasticity and engineering estimates, we project shifts from high-sulfur Western Kentucky coal to low-sulfur Eastern Kentucky coal, higher electric utility rates and manufacturing costs, and lower manufacturing employment. Impacts are always less than 6 percent of 1985 levels.     

Metoclopramide Reversal of Decreased Gastrointestinal Myoelectric and Contractile Activity in a Model of Canine Postoperative Ileus

Postoperative ileus is characterized by decreased gastrointestinal myoelectric activity and motility. Metoclopramide was used to treat experimentally induced postoperative ileus in six dogs. Contractile activity was monitored by extraluminal strain gages on the pyloric antrum and proximal segment of the duodenum, and myoelectric activity was measured by recording bipolar electromyograms (EMGs) at the pyloric antrum, pyloric canal, proximal segment of the duodenum, proximal and distal parts of the jejunum, and ileum. Measurements were obtained from animals without ileus (baseline) and those with ileus that were either untreated or treated with metoclopramide. Adynamic ileus was induced by rubbing a 50 cm segment of jejunum with a dry sponge for 5 minutes and exposing the bowel to the air for 30 minutes. Treated dogs received metoclopramide (0.4 mg/kg 4 times daily [QID] intravenously [IV]), whereas untreated dogs received a saline placebo, starting 1 hour after celiotomy closure. Recordings were made for 26 hours after induction of ileus. The phases of the migrating myoelectric complex (MMC) were identified and motility index values were determined. During ileus, the MMC phase II duration was increased at the duodenum and phase III duration was decreased at the antrum, pylorus, duodenum, and proximal segment of the jejunum (p less than 0.05). Motility index values were decreased at the antrum and duodenum during ileus (p less than 0.05). Treatment with metoclopramide reversed the MMC phase III inhibition at the antrum and pylorus, and partially reversed the inhibition at the duodenum and jejunum (p less than 0.05). Motility index values were restored to preoperative baseline values with metoclopramide treatment (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

EFFECT OF 2,4-D AND PICLORAM ON TRANSLOCATION OF 14C-ASSIMILATES IN VITIS VINIEERA L.

Summary. High concentrations of 2,4-D and picloram interfered with the downward movement of ¹⁴c-assimilates infield-grown vines. The interference in translocation was appreciably greater with picloram than it was with 2,4-D, Although basipetal translocation was retarded, translocation within the treated shoots continued from the vegetative part to the clusters. Translocation of 2,4-D appeared to follow the same route as ¹⁴c-assimilatcs for the most part. Formative effects were absent on untreated grape shoots although the adjacent shoots treated with 2,4-D or picloram on the same cordons were killed; however, formative effects were evident on some of the stump sprouts which developed after the vines were harvested. The malformed leaves on the stump sprouts were twelve or more nodes from the base of the shoots, while ¹⁴c was in the more basal leaves.
Thompson Seedless (Sultanina) rootings treated with 20 000 ppm 2,4-D or picloram transported less ¹⁴C to the roots than did the controls. Treatment with either herbicide resulted in a marked increase in the labelling of the stems.
Effet du 2,4-D et du pichlorame sur la migration de métabolites marqués au ¹⁴C dans Vitis vinifera L.     

Seasonal changes in a deep‐water fish assemblage in response to monsoon‐generated upwelling events

The coastal shelf of the Gulf of Oman experiences periodic upwelling events during the summer months that are driven by the southwest monsoon. It is unclear what role these events play in the spatial and temporal distribution of the region’s fish assemblage. We carried out trials on two different video techniques to characterize the habitat and fish assemblage along the continental shelf margin near Muscat, Oman. Exploratory surveys with a drift stereo‐video revealed three main habitat types: Sand, Reef and Megabenthos. Three areas were chosen for additional sampling using stereo‐BRUVS (‘baited’ remote underwater‐video systems). On two separate occasions (November 2005 and March 2006) replicate stereo‐BRUVS were deployed in each area stratified by the main habitat types. For each teleost and elasmobranch species encountered on the video, an estimate of total body length and the relative abundance (MaxN_i) was made. The stereo‐BRUVS recorded a wide range of demersal and pelagic teleosts including species of conservation interest such as sharks, rays and groupers. The drift stereo‐video recorded significantly fewer species than the stereo‐BRUVS (N = 15 versus N = 43). Species diversity from the stereo‐BRUVS increased by 96% in March 2006 (N = 41) compared to November 2005 (N = 23), a pattern consistent at all three areas. The structure of the overall fish assemblage (using canonical analysis of principal coordinates analysis) was highly variable both in time and space. There was ample evidence of strong habitat associations, particularly with depth and seasonal shifts in abundance and diversity. We argue the upward migration of oxygen‐depleted water into the shallow depths during the late monsoon displaces the demersal fish community along this coast.     

Existence Value,Contingent Valuation,and Natural Resources Damages Assessment

ABSTRACT The purpose of this paper is to review recent developments in economics and public policy with regard to environmental resources. We describe the traditional concepts of externalities, public goods, efficient property rights, and the more recent concept of existence values for wilderness areas and other natural resources. A feature is the inclusiveness of modem economic theory. We trace the development of economic approaches to estimating values. We briefly review approaches based on observable market behavior and contingent market responses. Contingent valuation plays a vital role in estimation because it is the sole technique available for estimating the potentially important existence values. Benefit-cost analysis for regulatory decisions and natural resource damages assessment for implementation of Superfund legislation are discussed. We conclude that estimates of existence values based on contingent valuation can be useful especially when the alternative is greater reliance upon an imperfect political process.     

ABSORPTION AND TRANSLOCATION OF HERBICIDES BY THOMPSON SEEDLESS (SULTANINA) CRAPE, VITIS VINIFERA L.

Summary. Absorption and translocation of ¹⁴C-labelled herbicides applied in culture solutions lo the roots and in concentrated drops to mature leaves of 'Thompson Seedless' (Sultanina) cuttings were studied. Neither 2,4-D nor paraquat, and only traces of 2,4,5-T translocated from the roots to the shoot. Dicamba, amitrole, diuron, monuron, simazine and atrazine readily moved from the roots to the shoots. The substituted ureas and s -triazines were mobile only in the xylem or cell walls (apoplast), while dicamba and amitrole were mobile in the apoplast and symplast (living protoplasm). Both 2,4-D and 2,4,5-T moved almost entirely in the symplast. Paraquat moved only slightly in either apoplast or symplast. Stability of the herbicides in the plants varied, as judged by the detection of label in ethanol-insoluble products. Dicamba was considerably more stable than 2,4,5-T which, in turn, was more stable than 2,4-D. Diuron was more stable than either atrazine or simazine. Amitrole largely was converted into ethanol-insoluble products in 30 days. Paraquat was not extractable with ethanol.
Absorption et migration d'herbicides chez une vigne: Thompson Seedless (Sultanina), Vitis vinifera L.