Cranial Approach to the Humerus for Repair of Fractures in Horses and Cattle

A cranial approach to the humerus was developed for application of a compression plate for repair of comminuted humeral fractures in a weanling foal, a calf, a heifer, and a mature cow. An incision was made from the cranial portion of the greater tubercle of the humerus to the radius. The cranial aspect of the humerus was exposed by retraction of the brachiocephalicus muscle and blunt dissection between the biceps brachii and brachialis muscles. A second plate was applied laterally in the heifer and cow by retraction of the brachialis muscle and elevation of the extensor carpi radialis muscle. Successful fracture reduction, alignment, and stabilization were achieved in all four animals.     

Factors affecting digestibility and in-vivo energy content of cat foods

Apparent digestibility and digestible energy (DE) content of 43 canned and 28 packeted samples of commercial cat foods were determined using panels of six adult domestic cats. Metabolizable energy (ME) content was also measured with 22 of the canned and 14 of the packeted foods. Mean apparent crude protein (CP), acid ether extract (AEE) and nitrogen-free extract (NFE) digestibility percentages of all foods (N = 71) were 78, 77 and 69. Apparent AEE and CP digestibility percentages increased in a curvilinear manner with intake; logarithmic regression curves explained 50 and 24 per cent of the variation in AEE and CP digestibility by intake. The use of modified Atwater factors over-estimated ME content of canned and packeted foods by 21 and 27 per cent respectively, compared with in vitro values. Twenty-one single or mulitple regression equations were generated predicting in-vivo DE or ME content of foods from laboratory analyses. The use of such equations in the practical definition of energy content of cat foods is discussed.     

Efficacy of four corn (Zea mays L.) herbicides when applied with flat fan and air induction nozzles

Twelve field experiments were conducted over a 4 year (2002–2005) period to determine the influence of the herbicide dose, nozzle type, spray volume, and spray pressure on herbicide efficacy in field corn ( Zea mays L.). The control of Abutilon theophrasti (velvetleaf ), Ambrosia artemisiifolia (common ragweed), Chenopodium album (common lambsquarters), Amaranthus powellii (green pigweed), and Echinochloa crus-galli (barnyard grass) was improved with the use of full herbicide doses compared to half doses of bromoxynil, glufosinate, dicamba, and nicosulfuron. The yield was increased for bromoxynil, glufosinate, and nicosulfuron when the full herbicide dose was used. When applied at the manufacturer's recommended dose, flat fan nozzles, compared to air induction (AI) nozzles, provided better control of A. theophrasti , A. artemisiifolia , and C. album with bromoxynil, A. artemisiifolia and C. album with dicamba, and E. crus-galli with nicosulfuron. Bromoxynil, in relation to weed control, was the only herbicide that was affected by the water carrier volume. By increasing the spray pressure with an AI nozzle, there was an improvement in the control of A. theophrasti , A. artemisiifolia, and C. album with the application of bromoxynil and E. crus-galli with the application of nicosulfuron, with a yield increase with bromoxynil. Overall, this study concludes that the optimum nozzle type, water carrier volume, and spray pressure is herbicide- and weed species-specific.     

Isolation, culture and ultrastructure of a xylem-limited bacterium associated with Sumatra disease of cloves

A xylem-limited bacterium (XLB) previously shown to be associated with Sumatra disease of clove trees was consistently isolated from diseased but not from healthy trees. Isolation of the XLB was most successful using freshly expressed bacterial ooze obtained from root and branch tissues with low to moderate levels of xylem vessel invasion in trees at early stages of disease. XLB were commonly isolated from trees with the rapid form of disease but infrequently from those with slow decline. Bacterial colonies grew slowly on nutrient agar, reaching a maximum diameter of 1 mm in 5-7 days at 28^oC. Cells of the bacterium were 0.5-0.6 μm in width and 1.0-1.5 μm in length and did not possess flagella. The bacterial envelope was strongly rippled and Gram negative.     

Sumatra disease in cloves induced by a xylem-limited bacterium following mechanical inoculation

Suspensions of a Gram negative, non motile nutritionally fastidious bacterium, cultured from clove trees affected by Sumatra disease and inoculated by needle puncture into the xylem of seedling cloves and young trees, caused the death of over 60% of the plants withing 2 year. Bacteria, confined to zylem vesssels, occurred throughout the vascular systems of dying plants and were also still active in some of the plants which survived for 3 years after inoculation. Bactria resembling those used as inoculum were readily reisolated form dying plants but not from any water-treated controls. Symptoms in experimental plants and the appearance and distribution of vessels occluded by bacteria were indistinguishable from those resulting from natural infection. All clove types tested were susceptible, including progeny from trees which had survived past disease attack. Result suggest the importance of using vigorously growing plants and providing protection against full sunlight during incubation for the successful establishment of beacterial infection in juvenile clove plants follwing mechanical inoculation.     

The State‐by‐State Economic Impacts of the 2002 Shutdown of the Los Angeles–Long Beach Ports

In previous research, the economic impacts of temporary shutdowns of the Los Angeles–Long Beach harbors were simulated after a hypothetical terrorist attack, applying the National Interstate Economic Model to estimate state‐by‐state as well as interindustry impacts. However, the unpredictable characteristic of terrorist attacks might not be applicable to the case of a ports shutdown such as the one caused by the lockout of September–October 2002. Market participants can be expected to have contingency plans based on anticipations of a strike or shutdown. Can we identify any of these in terms of the use of alternate ports, in terms of alternate modes or even alternate time periods? The purpose of this study is to examine these questions. The approach is elaborated by testing for the possible effects of trade diversion to other West Coast ports, transportation modes, and intertemporal substitutions. We use data from WISERTrade describing commodity‐specific trade for the major West Coast ports before, during, and after the 11‐day shutdown of the fall of 2002. Shippers’ ability to divert trade is a key ingredient in the economy's ability to withstand attacks and disruptions. The work estimates the impacts on 47 industrial sectors across 50 states (and the District of Columbia).     

Effect of amitrole and 2,4-D applied preplant and pre-emergence in soybean (Glycine max)

There is limited information on the effect of amitrole and 2,4-D ester applied preplant and pre-emergence in soybean (G lycine max L.) in Ontario, Canada. Six field trials were conducted over a 2 year period (2004 to 2005) at three Ontario locations to evaluate the response of soybean to amitrole or 2,4-D ester applied at 14 days preplant (DPP), 7 DPP, 1 day after planting (DAP), and 7 DAP. The application of amitrole resulted in as much as 5.8, 3.9, 1.7, and 1% visible crop injury in soybean at 7, 14, 28, and 56 days after emergence (DAE), respectively. There was no visible injury in soybean with any amitrole treatment at 56 DAE, except for amitrole applied at 7 DAP, which caused 1% visible injury in soybean at 2310 g ha⁻¹. The application of the 2,4-D ester caused ≤8.3, 9.7, 4.6, and 1.3% visible injury in soybean at 7, 14, 28, and 56 DAE, respectively. The visible injury decreased over time. There was no visible injury in soybean with any of the 2,4-D ester treatments at 56 DAE, except for the 2,4-D ester treatment applied at 7 DAP, which caused 1% visible injury at 1155 g ha⁻¹ and 1.3% visible injury at 2310 g ha⁻¹. Soybean generally responded similarly to amitrole and 2,4-D ester when applied at 14 and 7 DPP; however, soybean was more tolerant to amitrole compared to 2,4-D ester when applied at 1 or 7 DAP. The application of amitrole and 2,4-D ester resulted in no biomass or yield reduction in soybean compared to the weed-free, untreated control at all doses and application timings evaluated. Soybean is tolerant to the preplant and pre-emergence application of amitrole or 2,4-D ester at the doses evaluated.     

Large‐scale coherence in New England lobster (Homarus americanus), settlement and associations with regional atmospheric conditions

Time series of American lobster (Homarus americanus) postlarval settlement from southern New England to Atlantic Canada exhibit many common features, and a cluster analysis indicates a block of regions extending from Massachusetts to Maine that have coherent interannual variations. The spatial scale of this block suggests that variability in settlement is related to large‐scale, rather than local, processes. We examined the association between settlement at six reference regions and monthly mean atmospheric conditions (temperature, geopotential height, westerly and southerly wind components, and wind curl) from the North American Regional Reanalysis. We first extracted the dominant modes of variability in monthly averaged geopotential height, temperature, and wind curl. The leading mode from September, which represents high geopotential height, warm temperatures, and negative wind curl throughout the study area, was strongly correlated with settlement at most of the regions. The third mode from August, which represents enhanced southwesterly winds, was correlated with settlement in Rhode Island. Correlations between local atmospheric conditions and lobster settlement confirm the principal component results. Settlement was correlated to varying degrees with geopotential height (positive), temperature (positive) and wind curl (negative) with lobster settlement at the northern sites, with temperature being a stronger indicator in the north and curl a stronger indicator in the south. Rhode Island settlement was strongly correlated with August westerly winds. The correlation between settlement and atmospheric conditions could improve our understanding of stock‐recruit relationships for lobster populations and provides one mechanism for how climate change could impact lobsters.     

Estimating total nitrogen deposition in agroecosystems in northern China during the wheat cropping season

Atmospheric nitrogen (N) deposition has been poorly documented in northern China, an intensive agricultural and industrial region with large emissions of NHx and NOy. To quantify N deposition, total airborne N deposition was determined at three agricultural sites using a manual integrated total nitrogen input (ITNI) system during growth of winter wheat (Triticum aestivum L.) and Italian ryegrass (Lolium multiflorum Lam.) from September 2005 to May 2006. Total estimated N deposition averaged 54.9 and 43.2 kg N/hm2 across the three sites when wheat was grown to flowering and maturing, respectively. The average value was 50.2 kg N/hm2 when ryegrass was the indicator plant. Both indicator species gave similar total airborne N input results. The intermediate level of N supplied resulted in the highest N deposition, and the ratio of N acquired from deposition to total N content of the whole system decreased with increasing N supply to the roots. The contribution of atmospheric N to the total N content of the wheat and ryegrass sand culture systems ranged from 10% to 24%.