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Increasing worldwide environmental awareness is encouraging scientific research into developing cheaper, more sustainable materials. Industrial hemp fiber is one of the strongest and stiffest available natural fibers [K. L. Pickering, M. Priest, T. Watts, G. Beckermann, and S. N. Alam, J. Adv. Mater. 37, 15 (2005)] and therefore has great potential in composite materials. Incorporated into a thermoplastic matrix, it gives a structural material that is cheap, lightweight, and recyclable. However, natural fibers are commonly incompatible with common molding thermoplastics such as polypropylene, which limits the performance of the composites produced. The main objective of the current work was to investigate the use of fungi to treat hemp fiber to create better bonding characteristics in natural fiber reinforced polypropylene composites. X-ray diffraction (XRD), ζ-potential, lignin testing, thermal analysis, and scanning electron microscopy (SEM) were used to characterize the effect of treatment on hemp fibers. A combined alkali and fungi treated fiber composite produced the highest tensile strength of 48.3 MPa, an increase of 32% compared to composites with untreated fiber.

Four sets of green, side-matched specimens of radiata pine (Pinus radiata D. Don) sapwood were incubated with individual isolates of Ophiostoma floccosum, O. pluriannulatum, O. ips, O. piceae, Leptographium procerum and Sphaeropsis sapinea for 8 or 16 weeks, along with non-inoculated control samples. Three decay fungi, Gloeophyllum trabeum, Phlebiopsis gigantea and Schizophyllum commune, were included in the tests to serve as references for weight and toughness loss. Overall toughness and dry weight were not significantly (p

The morphologic response of the pulmonary arteries and lungs in cats was studied after a five month heartworm infection produced by transplantation of four adult heartworms/cat. One group of seven heartworm infected cats was not treated, another group of seven cats was treated with 97.5 mg of aspirin given twice a week, and the third group of six cats was given aspirin at a sufficient dosage to block in vitro platelet aggregation throughout the study. A fourth group of eight noninfected cats served as controls. Five months after heartworm infection, the cats were euthanized and the lungs perfusion fixed for light microscopy and scanning electron microscopy of the pulmonary arterial surfaces. All cats in the three heartworm-infected groups had live heartworms and the typical pulmonary arterial changes of heartworm disease at necropsy. The arterial surfaces, as viewed with scanning electron microscopy, had villus proliferations that were more numerous and exuberant than similar infections in dogs. Mean percentage of arterial surface involvement with villus proliferation of the nontreated heartworm infected cats was 67.3%; the aspirin treated cats, 73.8%; and the adjusted aspirin treated cats, 75.9%. The villi were myointimal proliferations in the small and medium-sized arteries. The more elastic arteries had a predominance of fibromuscular proliferation. All heartworm infected cats had arterial muscular hypertrophy of the small arteries, in contrast to only three of eight of the nonheartworm infected cats. The caudal lobar arteries were frequently obstructed with either villus proliferation, thrombi, and/or dead heartworms. The muscular arteries had branches with marked dilation, a condition associated with pulmonary hypertension in man. However, only three cats, one in each group, had pulmonary hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

A case of intracranial schwannoma is described in a young horse. Clinical signs developed slowly and were suggestive of a lesion involving the left cerebrum. The filly exhibited a change in mentation, and circled to the left. Visual impairment and decreased facial sensation were noted on the right side. A solitary schwannoma which compressed the left cerebrum was found at necropsy.

SummaryYeast phase H. capsulatum induced acute, progressive, fatal histoplasmosis in all of 9 dogs when inoculated intratracheally, but no clinical disease in all of 7 receiving the same inoculum by stomach tube. Mycelial phase produced no clinical evidence of infection in 9 and 10 normal dogs receiving intragastric and intratracheal inoculations, respectively. Cortisone treated dogs? however, were susceptible to intratracheal but not intragastric mycelial phase inoculations. Dogs previously receiving mycelial phase were resistant to reinfection with the same phase even when given cortisone; they succumbed to challenge with intratracheal yeast phase in the absence of cortisone.

1 Box ED: Life cycles of two Isospora species in the canary, Serinus canarius Linnaeus. J Protozool41:57, 1977 2 Dubey JP: A review of Sarcocystis of domestic animals and of other coccidia of cats and dogs. J Am Vet Med Assoc 169:1061, 1976 3 Fowler ME: Doves, hornbills, toucans, and tinamous (Columbiformes, Coraciiformes, Piciformes, and Tinamiformes). In: Zoo and Wild Animal Medicine, ed. Fowler, Griner, Heuschle, Moms, and Sedgwick, p. 325. WB Saunders Co, Philadelphia, 1978 4 Frenkel J K Protozoan diseases of zoo and captive mammals and birds. In: The Comparative Pathology of Zoo Animals, ed. Montali and Migaki, p. 329. Smithsonian Institution, Washington, DC, 1980 5 Frenkel J K Toxoplasmosis: mechanisms of infection, laboratory diagnosis and management. Curr Top Pathol 54:28, 1971 6 Pendergraph GE: A serological study of toxoplasmosis in wild pigeons and their possible role in its dissemination. J Elisha Mitchell Sci SOC 88:208, 1972 7 Petrak M L Toxoplasma and toxoplasmosis. In: Diseases of Cage and Aviary Birds, 2nd ed., p. 552. Lea and Febiger, Philadelphia, 1982 8 Shadduck JA, Pakes SP: Protozoal and metazoal diseases. In: Pathology of Laboratory Animals, ed. Benirschke, Garner, and Jones, p. 16 13. Springer-Verlag, New York, 1978 9 Turner GVS: Some aspects of the pathogenesis and comparative pathology of toxoplasmosis. J S Afr Vet Assoc 49:3, 1978 10 Wallach JD, Boerer W J: Diseases of Exotic Animals, p. 83 1. WB Saunders Co, Philadelphia, 1983

Viral transformation affects certain developmental processes by blocking the differentiation of cells such as primitive muscle cells (myoblasts) or primitive red blood cells (erythroblasts). Embryonic quail myoblasts, transformed with a temperature-sensitive (ts) mutant of Rous sarcoma virus (RSV) are blocked in differentiation at the viral permissive temperature of 35 degrees C, but fuse to form myotubes at the nonpermissive temperature of 41 degrees C. We have shown that viral transformation of quail myoblasts also causes transcription of non-muscle-specific genes, ie, globins at 35 degrees C that are not observed in uninfected myoblasts or myotubes. Transformed myoblasts shifted to 41 degrees C for 5 days still contain these globin transcripts. Both alpha-like and beta-like globins are expressed.

Virgin female Sprague-Dawley rats (50 days of age) were administered a single intragastric 10-mg dose of 7,12-dimethylbenz(a)anthracene (DMBA). Twenty-one days later they were placed on diets containing either 20% corn oil (CO), 15% menhaden oil plus 5% corn oil (MO + CO), 20% CO plus 0.5% w/w of the irreversible ornithine decarboxylase inhibitor, D,L-2-difluoromethylornithine (CO + DFMO), 20% CO plus 0.004% w/w of the cyclooxygenase inhibitor indomethacin (CO + INDO), 20% CO + 0.004% INDO + 0.5% DFMO (CO + INDO + DFMO), or 15% MO + 5% CO + 0.5% DFMO (MO + CO + DFMO). The incidence of DMBA-induced mammary tumors was significantly reduced in rats fed diets containing DFMO but not in rats fed the diet containing indomethacin. Incidences of mammary tumors at 16 weeks post-DMBA were 86% in rats fed the CO diet, 83% in rats ingesting the diet containing CO + INDO, 28% in rats fed CO + DFMO, 32% in rats fed diet containing CO + INDO + DFMO, 59% in rats fed the MO + CO diet, and 24% in rats fed the MO + CO + DFMO diet. The average number of tumors and tumor burden per tumor-bearing rat were reduced and tumor latency was increased in all rats fed diets containing DFMO. Body weight gain, but not food intake, of rats fed the 20% fat + 0.5% DFMO diets was significantly less than in rats fed the 20% fat diets. Prostaglandin E and leukotriene (LTB4) syntheses, ODC activity and mammary tumorigenesis were significantly inhibited by feeding the diet containing menhaden oil or by adding 0.5% DFMO to any of the high fat diets. Feeding a 20% CO diet containing 0.004% INDO significantly reduced prostaglandin synthesis and ODC activity and increased LTB4 synthesis of mammary tumors but did not inhibit mammary tumorigenesis. This study suggests that the 5-lipoxygenase product LTB4 may be involved in mammary tumor production. Whereas a decrease in LTB4 appears to be associated with a decrease in tumorigenesis, an increase (as seen in the indomethacin group) was not associated with any change in the tumorigenic response.

The purpose of this paper is to present an overview description of the VECTOR-0 and VECTOR-1 models developed by Vector Research, Incorporated, for the Weapons Systems Evaluation Group (WSEG). The models are intended to describe the joint activities of NATO army units and air force tactical aircraft engaging advancing threat forces who are also supported by tactical aircraft. The models are for use in estimating net assessments and in generating data to make trade-offs among the various forces and systems involved in such an engagement.

Bovine respiratory anatomy and physiology were reviewed and considered in relationship to the pathogenesis of pulmonary disease. Factors which may predispose cattle to respiratory disease included a small physiological gaseous exchange capacity, greater basal ventilatory activity, and greater anatomical compartmentalization of the lung as compared with other mammals, a low level and atypical bioactivity of bovine lysozyme, and low numbers of macrophages within the alveolar lumen.

Experimentally induced and naturally acquired lungworm infections (Didelphostrongylus and Capillaria) were studied in opossums, Didelphis marsupialis. Each of 4 helminth-free opossums were experimentally infected with 250 3rd-stage Didelphostrongylus hayesi larvae. At 2 and 8.5 months after infection, 2 animals were necropsied. Hypertrophy of pulmonary smooth muscle characterized D hayesi infections, with lesions pronounced in the vicinity of helminths. There was mucous bronchitis characterized by peribronchial gland hyperplasia, lymphoid nodule formation, and exudation of mucus and eosinophils into bronchioles. Lung from 4 opossums harboring natural infections of D hayesi or Capillaria or both was examined. Concomitant infections produced multifocal, indurated lesions often resulting in generalized consolidation. Microscopic examination revealed pulmonic damage consisting of hypertrophy of smooth muscle, extensive peribronchiolar adenomatoid hyperplasia of alveolar epithelium, and diffuse areas of granulomatous interstitial pneumonia. Capillaria provoked well-defined granulomas, and frequently only eggs and cuticular debris were contained within the lesions. Loss of pouch young by 1 naturally infected feamle was associated with extensive verminous pneumonia.

One-day-old White Leghorn chicks were fed graded levels (0, 10, 50, 100 and 1,000 ppm) of pentachloronitrobenzene (PCNB; quintozene) up to 8 weeks. Each treatment group consisted of 90 randomly selected birds (2 replications of 45 birds each). Body weight gains were significantly lower at the 1,000-ppm treatment level. Histopathologic examination of brain, liver, pancreas, small intestine, gizzard, spleen, kidney, lung, and heart failed to reveal lesions in either control or treated groups. Bioaccumulation of PCNB or its metabolites (pentachloroaniline and pentachlorophenylmethylsulfide) in tissues only occurred in trace or very low concentrations. However, trace contaminating of PCNB, eg, hexachlorobenzene (HCB) and pentachlorobenzene (PCB) accumulated in tissues to a significant degree. Tetrachloronitrobenzene, another contaminant of PCNB, was found in only the adipose and cardiac tissues following the feeding of 1,000 ppm PCNB. Storage of PCNB, HCB, and PCB in adipose and other tissues was linearly related to the amount of PCNB in the ration.

Cattle given intraruminal administration of 4-ipomeanol, a furanoterpenoid originally obtained from sweet potatoes infected with Fusarium solani (F. javanicum), developed a respiratory syndrome clinically and histologically indistinguishable from atypical interstitial pneumonia. There were edema and emphysema in the lungs and mediastinum. The maximum nonlethal oral dose of 4-ipomeanol was estimated to be between 7.5 and 9 mg/kg of body weight.

A patient presenting with signs and symptoms of gastric outlet obstruction and acute oliguric renal failure underwent early endoscopic examination. A large gallstone was seen obstructing the duodenal cap. Bouveret's syndrome and the role of endoscopy in early diagnosis are discussed.

Recently weaned pigs were infected aerogenically with Haemophilus (Actinobacillus) pleuropneumoniae, serotype 5. At three, six, 12, and 18 hours and one, two, four and seven days after exposure to haemophili a pair of animals were killed and necropsied. Pulmonary oedema with multifocal petechial haemorrhages and a diffuse neutrophilic bronchiolitis and alveolitis were observed at three and six hours after infection. Focal areas of coagulative necrosis developed in areas of intense suppuration at 12 and 18 hours after infection. At one and two days after infection, necrotic areas were surrounded by dense bands of degenerating leucocytes and contained unidentifiable round and elongated cells characteristic of this disease. In subacute lesions a thick layer of granulation tissue formed around the outer margin of developing abscesses. Most of the round and elongated cells in alveolar exudates could not be identified by enzyme histochemistry or electron microscopic examination. Neutrophils in various stages of degeneration and deterioration provided strong evidence that some of the cells were of this type. These findings suggest that neutrophils may play an early and significant role in development of lesions.

The increase in tension of the gastroesophageal high pressure zone after fundoplication and hiatal hernia repair could represent either a mechanical effect or enhanced smooth muscle tone of the lower esophageal sphincter. Determination of the response of this high pressure zone to cholinergic stimulation, a protein meal and deglutition before and after Belsey Mark IV fundoplasty in seven patients with intractable reflux indicates the latter. Fundoplication resulted in a resting tension of the high pressure zone significantly greater than that found preoperatively but similar to that of controls. This normotensive postoperative high pressure zone had properties of a physiologic lower esophageal sphincter, that is, normal relaxation to deglutition, a response to a protein meal and a response to cholinergic stimulation with edrophonium. In response to edrophonium, evidence of a partial improvement in lower esophageal sphincter smooth muscle function was found postoperatively when compared with the response of controls and in patients preoperatively. The response to a protein meal postoperatively remained similar to that noted preoperatively, which was significantly less than the response of controls. Therefore, the increase in tension of the high pressure zone after fundoplication and hiatal hernia repair appears to result from improved function of the lower esophageal sphincteric smooth muscle.

The lung lesions produced by multiple short-term intratracheal instillations of saline solutions of sodium zirconium lactate (NaZL), zirconium-aluminum-glycine hydroxychloride complex (ZAG), and aluminum chlorhydrate (ACH) in hamsters were studied by light and electron microscopy. These solutions produced lesions beginning with exudative pneumonia followed by pneumonitis (interstitial pneumonia) and foreign body granulomas. Electron microscopic microprobe analysis demonstrated the metallic component of the instilled compounds in membrane-bound cytoplasmic inclusions of macrophages. The lesions produced by NaZL and ZAG were similar to those produced by ACH. These lesions were also similar to those in previous reports of aerosol exposure of animals to zirconium or aluminum, or to other unrelated compounds.

The pulmonary clearance rate of Serratia marcescens was determined in 17 calves exposed to an aerosol from a modified Hendersen apparatus. The mean bovine pulmonary clearance was 50.2 +/- 4.1% at postaerosolization hour (PAH) 1, 72.5 +/- 7.0% at 2 hours, 88.6 +/- 5.2% at 4 hours, 97.3 +/- 2.8% at 8 hours, and 99.9% at PAH 24 and 48. Regional pulmonary mean percent retention (MPR) of S marcescens in 10 calves was determined in dorsal or ventral and in cranial or caudal regions. Dorsal MPR was less than ventral MPR for PAH 1, 2, and 4, whereas cranial MPR was greater than caudal MPR for PAH 1, 2, 4, and 8. Difference in regional airway oxygen tensions was suggested as the most probable reason for differing regional MPR values.

Lung and alveolar macrophage studies were conducted following experimental immunostimulation of calves with Freund's complete adjuvant (FCA). Intravenous administration of FCA to calves 35 days before aerosol exposure to serratia marcescens resulted in a 53.1% reduction in the 2-hour pulmonary mean percent retention of the organism when compared to control calves. FCA treatment increased alveolar macrophage concentration (cells/g lung) by 30.9%. Lymphoid and granulomatous responses were increased in the lungs of treated calves.