Photodissociation channels for N2O near 130 nm studied by product imaging.

The photodissociation of N(2)O at wavelengths near 130 nm has been investigated by velocity-mapped product imaging. In all, five dissociation channels have been detected, leading to the following products: O((1)S)+N(2)(X (1)Sigma), N((2)D)+NO(X (2)Pi), N((2)P)+NO(X (2)Pi), O((3)P) + N(2)(A (3)Sigma(+) (u)), and O((3)P) + N(2)(B (3)Pi(g)). The most significant channel is to the products O((1)S) + N(2)(X(1)Sigma), with strong vibrational excitation in the N(2). The O((3)P) + N(2)(A,B):N((2)D,(2)P) + NO branching ratio is measured to be 1.4 +/- 0.5, while the N(2)(A) + O((3)P(J)):N(2)(B) + O((3)P(J)) branching ratio is determined to be 0.84+/-0.09. The spin-orbit distributions for the O((3)P(J)), N((2)P(J)), and N((2)D(J)) products were also determined. The angular distributions of the products are in qualitative agreement with excitation to the N(2)O(D (1)Sigma(+)) state, with participation as well by the (3)Pi(v) state.

Quantum yields for product formation in the 120-133 nm photodissociation of O2.

The photodissociation of O(2) in the region from 120-133 nm has been investigated using product imaging. The spectrum in this region is dominated by transitions from the ground state to the first three vibrational levels of the E (3)Sigma(u) (-) state. The O((1)D)+O((3)P) channel is the only product channel observed by product imaging for dissociation at either 124.4 nm or 120.4 nm. The O((1)D(2)) product is aligned in the molecular frame in such a way that its J vector is perpendicular to the relative velocity vector between the O((1)D) and the O((3)P). The variation in the anisotropy of dissociation is approximately predicted by considering transitions on individual lines and then taking into account the coherent excitation of overlapping resonances. At 132.7 nm, both the O((1)D)+O((3)P) and the O((3)P)+O((3)P) channels are observed with branching ratios of 0.40+/-0.08 and 0.60+/-0.09, respectively. At 130.2 nm, the quantum yield for production of O((1)D) is 0.76+/-0.28.

Ovarian torsion as a cause of colic in a neonatal foal.

A 1-week-old Morgan filly was evaluated because of acute signs of abdominal pain of 7 hours' duration. On admission, physical examination findings were unremarkable; however, radiography of the abdomen revealed slight distention of the small intestine. Signs of abdominal discomfort were detected during several hours of observation. Abnormalities were not evident during gastroscopic evaluation. Therefore, exploratory laparotomy was performed. The only abnormal finding was infarction of the left ovary secondary to a 720 degrees torsion of the mesovarium. The vascular pedicle was ligated and the ovary was removed. Recovery from anesthesia and surgery was satisfactory, and the foal was discharged from the hospital 5 days after surgery. Two years later, it appeared to be clinically normal. Review of the recent veterinary literature failed to find reports of ovarian torsion as a cause of signs of abdominal pain in horses. Ovarian torsion should be considered as a differential diagnosis in fillies with acute signs of abdominal pain, especially when laparotomy fails to reveal abnormalities associated with the gastrointestinal tract.

Laparoscopic cryptorchidectomy in standing horses.

OBJECTIVE: The purpose of this study was to determine the feasibility of using laparoscopy to remove cryptorchid testes from standing horses. STUDY DESIGN: Prospective clinical study. ANIMALS OR SAMPLE POPULATION: Eleven client-owned horses ranging in age from 4 months to 2 years. METHODS: Abdominal insufflation was initiated and maintained using a 20 F insufflation tube, attached via a stopcock, to the low pressure regulator on a standard carbon dioxide pressure tank. After trocar and laparoscope placement in the ipsilateral flank the testes were identified. Local anesthesia of the structures to be manipulated was administered through the instrument channel on the operative laparoscope, using a catheter with a needle attached. Testes were grasped with large laparoscopic forceps and exteriorized through the abdominal wall. Ligation and transection of the mesorchium was extracorporeal. The descended testes were removed using a standard standing technique. RESULTS: Complications were minor, including mild colic in one horse. The mean surgical time for standing laparoscopic cryptorchidectomy and castration of these colts was 58.9 +/- 24.3 minutes. CONCLUSIONS AND CLINICAL RELEVANCE: Standing laparoscopic cryptorchidectomy, using the instrumentation described, is a safe and practical technique in young horses.

Epidemiologic study of toxoplasmosis on a sheep ranch.

An epidemiologic study was done on a ranch in northern California on a flock of ewes that had a history of abortions, mummified fetuses, weak or stillborn lambs, and failure to conceive. Of 56 ewes tested, 33 (59%) had serum agglutinating antibodies against Toxoplasma gondii, with an unusually high proportion of high titers. Over a 2-year-period, reproductive problems were higher (39% to 42%) among the seropositive ewes than among the seronegative ewes (9% to 33%). Of 89 sera received from persons and 7 species of animals on the ranch, 44 (49%) were found to be seropositive to T gondii, including seropositive members of a family of 6. The rancher's wife and teenage daughter, both of whom were involved with lambing, had serum titers exceeding 4,096. Other members of the family not involved with lambing were seronegative by the indirect hemagglutination test. The 2 infected persons are known to have come in contact with placentas, birth fluids, fetuses, and colostrums from these infected ewes.

The ethnobotany of chamairo: Mussatia hyacinthina.

Recent fieldwork in the eastern lowlands of Bolivia and Peru has revealed a traditional use of coca (Erythroxylum coca Lam.) as a medicine and stimulant that is distinct from the well-documented customs of the Northwest Amazon and the Andean highlands. In Bolivia some nine indigenous tribes centered mainly in the Rio Beni drainage masticate entire sun-dried coca leaves, yet use as an alkaline additive the crude ash of the spathe or leafbase of the motacú palm (Scheelea princeps (Mart.) Karst.). To the quid they add a piece of the bark of the bignoniaceous liana chamairo (Mussatia sp.), which markedly sweetens the chew. In the montaña of Peru, the liana is also used and a new species is reported from the upper Apurimac river. The ethnobotany of chamairo throughout its range is examined and the need for pharmacological screening is emphasised.

The ethnomedicine of the Waorani of Amazonian Ecuador.

The Waorani Indians of eastern Ecuador are one of the least acculturated tribes in South America and hence provide a unique opportunity for studying the role of medicinal plants in an isolated Amazonian people. Biomedical studies conducted by a team from Stanford and Duke Universities have revealed a surprising dearth of endemic disease among recently contacted Waorani. An intensive ethnobotanical study in the spring of 1980 found a perspicacious knowledge of ethno-ecology among all adult Waorani, but discovered relatively few medicinal plants. Partial results of this survey and a discussion of Waorani disease concepts are presented. The implications in terms of the origin of plant medicines among indigenous peoples are discussed. Are the Waorani unique because of their isolation or do they represent a pattern of medicinal plant use closer to the aboriginal situation before the impact of Western disease? The conclusions challenge the orthodox view of the native and the origins of his prodigious knowledge of medicinal botany.

The ethnobiology of the Haitian zombi.

For many years students of Haitian society have suggested that there is an ethnopharmacological basis for the notorious zombies, the living dead of peasant folklore. The recent surfacing of three zombies, one of whom may represent the first potentially verifiable case, has focused scientific attention on the reported zombi drug. The formula of the poison was obtained at four widely separated localities in Haiti. The consistent ingredients include one or more species of puffer fish (Diodon hystrix, Diodon holacanthus or Sphoeroides testudineus) which contain tetrodotoxins, potent neurotoxins fully capable of pharmacologically inducing the zombi state. The ingredients, preparation and method of application are presented. The symptomology of tetrodotoxication as described in the biomedical literature is compared with the constellations of symptoms recorded from the zombies in Haiti. The cosmological rationale of zombies within the context of Voodoo theology is described. Preliminary laboratory tests are summarized.