Dynamical effects on the O(3P) + D2 reaction and its impact on the Λ-doublet population.

The O(3P) + D2 → OD(2Π) + D reaction presents the peculiarity of taking place on two different potential energy surfaces (PESs) of different symmetry, 3A' and 3A'', which become degenerate for collinear configurations where the saddle-point of the reaction is located. The degeneracy is broken for non-collinear approaches with the energy on the 3A' PES rising more abruptly with the bending angle, making the frequency of this mode higher on the 3A' state. Consequently, the 3A' PES should be less reactive than the 3A'' one. Nevertheless, quantum scattering calculations show that the cross section is higher on the 3A' PES for energies close to the classical reaction threshold and rotationless reactant. It is found that the differences between the reactivity on the two PESs are greater for low values of total angular momentum, where the centrifugal barrier is lower and contribute to the higher population of the Π(A') Λ-doublet states of OD at low collision energies. At high collision energies, the Π(A') Λ-doublet state is also preferentially populated. Analysis of the differential cross sections reveals that the preponderance for the Π(A') Λ-doublet at low energies comes from backward scattering, originating from the reaction on the 3A' PES, while at high energies, it proceeds from a different mechanism that leads to sideways scattering on the 3A'' PES and that populates the Π(A') manifold.

Quantum study of reaction O(3 P) + H2 (v, j) → OH + H: OH formation in strongly UV-irradiated gas.

The reaction between atomic oxygen and molecular hydrogen is an important one in astrochemistry as it regulates the abundance of the hydroxyl radical and serves to open the chemistry of oxygen in diverse astronomical environments. However, the existence of a high activation barrier in the reaction with ground state oxygen atoms limits its efficiency in cold gas. In this study we calculate the dependence of the reaction rate coefficient on the rotational and vibrational state of H2 and evaluate the impact on the abundance of OH in interstellar regions strongly irradiated by far-UV photons, where H2 can be efficiently pumped to excited vibrational states. We use a recently calculated potential energy surface and carry out time-independent quantum mechanical scattering calculations to compute rate coefficients for the reaction O(3 P) + H2 (v, j) → OH + H, with H2 in vibrational states v = 0-7 and rotational states j = 0-10. We find that the reaction becomes significantly faster with increasing vibrational quantum number of H2, although even for high vibrational states of H2 (v = 4-5) for which the reaction is barrierless, the rate coefficient does not strictly attain the collision limit and still maintains a positive dependence with temperature. We implemented the calculated state-specific rate coefficients in the Meudon PDR code to model the Orion Bar PDR and evaluate the impact on the abundance of the OH radical. We find the fractional abundance of OH is enhanced by up to one order of magnitude in regions of the cloud corresponding to A V = 1.3-2.3, compared to the use of a thermal rate coefficient for O + H2, although the impact on the column density of OH is modest, of about 60%. The calculated rate coefficients will be useful to model and interpret JWST observations of OH in strongly UV-illuminated environments.

Multi- and single-reference methods for the analysis of multi-state peroxidation of enolates.

In spite of being spin-forbidden, some enzymes are capable of catalyzing the incorporation of O2(Σg-3) to organic substrates without needing any cofactor. It has been established that the process followed by these enzymes starts with the deprotonation of the substrate forming an enolate. In a second stage, the peroxidation of the enolate formation occurs, a process in which the system changes its spin multiplicity from a triplet state to a singlet state. In this article, we study the addition of O2 to enolates using state-of-the-art multi-reference and single-reference methods. Our results confirm that intersystem crossing is promoted by stabilization of the singlet state along the reaction path. When multi-reference methods are used, large active spaces are required, and in this situation, semistochastic heat-bath configuration interaction emerges as a powerful method to study these multi-configurational systems and is in good agreement with PNO-LCCSD(T) when the system is well-represented by a single-configuration.

[Morphological changes in broilers produced by feeding antibiotics]. / Morfologichni promeni u broileri, poluchavali s khranata nutritivni antibiotitsi.

Morphologic studies were carried out on the liver, kidneys, and small intestine of broiler birds that had been given antibiotics with the feed (virginiamycin, 20.0 ppm, flavomycin, 4.8 ppm, and avotan, 10.0 ppm) in the course of 49 days, kept with a group of controls. The liver of the test birds showed protein and fatty dystrophy, and the kidneys--protein dystrophy. The small intestine showed thinning of the wall and increase in the villi intestinales length. The manifestation of the morphologic changes depended on the amount of the antibiotic taken in. Those of the birds that were offered flavomycin had well manifested lesions, while in birds that were given virginiamycin and avotan only the lesions were more slightly expressed.

[Demonstration of a reovirus in helicopter disease of broilers]. / Dokazvane na reovirus na "khelikoptera bolest" pri broileri.

A reovirus was isolated from 5-13-day-old broiler birds with signs of the so-called helicopter disease--one of the forms of the malabsorption syndrome. A number of organs were investigated (trachea, liver, spleen, bursa of Fabricius, proventricular stomach, and tendon sheath of musculus gastrocnemius). The virus was isolated from the proventricular stomach and the tendon sheath in cell cultures of chick embryo kidney as well as in 5-7-day-old chick embryos inoculated in the yolk sac. The remaining organs proved virologically negative. All organs, including the primarily positive ones, were shown to be virologically negative upon the inoculation of chick embryo fibroblast cultures and of chorioallantoic membranes of 10-11-day-old chick embryos. The isolate was identified as an avian reovirus, and was denoted with the initials R-85--on the grounds of its biologic and physico-chemical properties, of its morphology (negative-contrast electron microscopy), and of its morphogenesis (ultrathin electron-microscopic cross sections). Investigated were the histopathologic changes in chick embryos inoculated with the R-85 reovirus and the pathologic changes in the liver of spontaneously affected birds.

[Histogenesis of leukemic changes in cows]. / Khistogeneza na levkoznite izmeneniia pri kravite.

A histopathologic study was carried out on lymph nodes and viscera of 98 cows and 28 heifers that responded positively in serologic examinations for leukosis. The animals did not exhibit clinical and paraclinical symptoms, neither were there found any morphologic changes characteristic of leukosis. There existed activation and proliferation of the reticuloendothelial tissue in the sinuses of the lymph nodes. The same response was shown by the endothelium of the capillaries in visceral organs. There was also metaplasia that concerned mainly the connective tissue cells of the lymph node trabeculas as well as the adventitial cells of the vascular walls. It was considered that the infection could be manifested morphologically as a reticuloendotheliosis. By its clinical course and morphologic manifestation bovine leukosis resembles some other virus diseases that have been systematized as "delayed virus infections'.

[Histochemical changes in leukemia in cattle]. / Khistokhimichni promeni pri levkoza po govedata.

Histochemical investigations were carried out to demonstrate the activity of succinic dehydrogenase, diphosphopyridine-nucleotid-diaphorase, alkaline phosphatase, and acid phosphatase in the liver, kidneys, lymph nodes, and heart muscle of a total of 20 cows with positive serologic response for leukosis as well as in organs of 2 normal controls. It was found that the lymphoid cells of the leukotic proliferations and the activated endothelial and adventitial cells of the blood vessels had high alkaline phosphatase activity and negligibly expressed acid phosphatase activity. Dehydrogenase activity was low in the lymphoid-cell proliferations and in the activated cell of the vessels. The cell metabolism of the leukotic proliferations was like-wise disturbed. Histochemical methods of investigations could be used test-like in the diagnosis of bovine leukosis.

[Morphological changes in chickens receiving cadmium with the feed]. / Morfologichni promeni pri pileta, poluchavali kadmii s khranata.

An experiment was carried out with a total of 100 broiler chickens of the Plymouth Rock breed. From hatching up to the 56th day of age they were offered a maize-soybean ration that was balanced in terms of nutrients and exogenically supplemented with cadmium at various rates in the form of cadmium chloride. The birds were divided into five experimental groups. The first group was given the basic ration with 2.5 mg Cd per kg of feed. The second group was given the same ration with 5 mg Cd; the third group--the same feed with 10 mg Cd; and the fourth group--the same ration with 20 mg Cd. The morphologic studies revealed that the presence of Cd in the feed led to severe dystrophic and necrotic changes accompanied with hemorrhages in the kidneys, heart muscle, and liver. Besides, the birds of the second and third group showed thinning and prolongation of villi intestinales, and those of the fourth group--shortening and thickening of the villi in the small intestine. These changes were indicative of chronic toxic lesions.

[Single-cell bacterial protein in the mixed feeds for early weaned piglets]. / Ednokletuchen bakterialen protein v kombinirani furazhi za rano otbiti praseta.

An experiment was carried out with a total of 21 hybrid Camborough pigs divided into three groups--group I, controls; group II, with 4 per cent of single-cell protein in the feed; and group III, with 8 per cent of such protein in the feed. The rations were balanced in terms of the basic feedstuffs. The pigs were kept under observation up to the age of 90 days. Three animals were periodically killed each time for investigation. Studied was the content of the total thiamine in the liver and the incorporation of the labelled 35s-thiamine in the jejunum. A histologic examination was also carried out of the jejunal mucosa and the liver. It was established that the inclusion of single-cell bacterial protein into the ration produced a positive effect on the total thiamine content of the liver. The group that was offered 8 per cent of this protein source showed reduced level of 35s-thiamine incorporation in the jejunum. Histologically, there were shortening and thickening of the intestinal villi along with signs of protein dystrophy in the liver epithelial cells in the case of animals given single-cell bacterial protein with the feed.

[Cytological and cytochemical studies of cell cultures infected with the avirulent viral mutant MK 35 of the pseudorabies virus]. / Tsitologichni i tsitokhimichni prouchvaniia na kletuchni kulturi, zarazeni s avirulentniia virusen mutant MK 35 na Pseudorabies virus.

Cytological and cytochemical studies were carried out of cell cultures of chick embryo fibroblasts infected with the vaccinal mutant strain MK 35 (4.8 X 10(7) PFU) of the Pseudorabies virus. It was found that the first cytologic changes in the infected cultures presented definite focal character. In the first hours of infection several rounded cells were included only, while later on an increasing number of cells were involved, and the foci grew in size. The cytoplasma of the infected cells contained inclusions which were small, spherical, basophilic, and Foelgen positive; six hours later the cytoplasmatic inclusions became larger, oval, acidophilic, surrounded by a brighter area, and were Fölgen-negative. Parallel to the cytologic changes in the infected cell cultures there set in metabolic disturbances and changes in the enzymatic activity. The infected cells showed enhanced lactate dehydrogenase, diphosphopyridin-nucleotide diaphorase, thiamine pyrophosphatase, and alkaline phosphatase activity and suppressed succinate dehydrogenase and acid phosphatase activity. These studies were said to reveal new biologic properties of the vaccinal mutant virus.

[Effect of colostral antibodies on the development of immunity in piglets immunized with live vaccine]. / Vliianie a kolastrenite protivotela vurkhu na imuniteta pri praseta, vaksinirani s zhiva vaksina.

Pigs of sows treated with a live vaccine were in turn vaccinated with a live vaccine at different age. Part of them were challenged with a virus at 60 days of age, the remaining -- at 90 days. The pigs were kept under clinical observation, and were killed on the 10th day following challenge in order to be thoroughly investigated. It was found that the passive immunity (virus-neutralizing antibodies) in pigs of twice (live vaccine) treated sows persisted for 4 to 5 weeks after birth. It dropped steplike, however, the interference of the vaccinal virus speeded up the process -- the earlier the vaccination the faster the exhaustion of immunity. The passive immunity was found to neutralize the vaccinal virus and hamper the building of active immunity. The presence of eosinophile leukocytes in the lymph nodes, tonsils, and spleen of the vaccinated pigs spoke of an immune reaction.

[Comparative pathomorphological studies of piglets infected with different strains of the pseudorabies virus]. / Sravnitelni patomorfologichni prouchvaniia pri praseta, zarazeni s razlichni shtamove na psevdorabiesniia virus.

Studied were morphologically the central nervous system and the internal organs of a total of 40 experimentally infected pigs-10 infected with the virulent strain B (5.2 C 10(6) PFU), 10 infected with the slightly virulent strain K (4.8 X 10(6) PFU), and 20 infected with the vaccinal mutant strain MK 25 (2.4 X 10(6) PFU), along with 4 control pigs. Histologically, all treated animals showed changes in the central nervous system characteristic of nonsuppurative meningoencephalitis. The lesions were more strongly expressed in the pigs infected with the virulent strain. Those of the animals treated with the MK strain presented changes that were similar to the changes observed in the pigs of the remaining two groups. By intensity and size, however, they were more slightly manifested and tended toward rapid limitation and lower frequence and dimension. The animals infected with strain K mad also changes in the lungs - interstitial pneumonia of lymphohistiocytis type. Those injected with the MK 25 strain presented numerous macrophages in the tonsils and lung lymph nodes, which was referred to as the morphologic expression of immunogenesis. The morphologic differences observed in the course of Aujeszky's disease in the individual test groups of pigs were due to the varying virulence and tissue tropism of the pseudorabic virus strains used. Studies revealed that the strongly virulent strains were predominantly neurotropic, while the slightly virulent ones were to a lesser extent neurotropic but were shown to be strongly pneumotropic.

[Biological properties of the MK 35 mutant of Aujeszky's disease virus (Pseudorabies virus)]. / Biologichni svoistva na mutant MK 35 na virusa na bolestta na Aueski (pseudorabies virus).

Clinical, virological, and morphological studies were carried out with a total of 15 twenty-day-old pigs and 55 rabbits of 2.5 kg body weight. All were experimentally infected with a new mutant, MK 35 (3.5 x 10(7) plaque forming units) of the pseudorabies virus. The changes taking place in the test animals were followed up in their dynamics from the first to the thirtieth day after injecting the virus. No clinical signs speaking of the development of Aujeszky-s disease were noted, neither was the virus isolated from the tonsils, lungs, lymph nodes, and the central nervous system of the treated animals. Histologically, there was in the central nervous system a slightly expressed nonsuppurative meningoencephalitis which was most clearly manifested on the fourth day after the animals were infected. Later on the changes appeared to be more slightly visible, and on the 8-10th day they were no longer seen. At the 48th hour following the inoculation and up to the end of the experiment eosinophil leukocytes were present in the tonsils, lymph nodes, and spleen of all infected animals as well as within the parenchyma of the adrenal glands of the pigs only. The presence of eosinophil leukocytes in the enumerated organs of the test animals is referred to as the morphologic manifestation of immunogenesis--the result of an enhanced defense status of the host induced by the MK 35 mutant of the pseudorabic virus.

[Pathomorphological changes in colibacteriosis in pigs]. / Patomorfologichni izmeneniia na kolibakteriozata pri praceta.

A total of 46 suckling piglets spontaneously affected with colibacteriosis and 20 pigs aged from 1 to 10 days, experimentally infected with two strains of Escherichia coli (0149 and 0138) were investigated morphologically. Both in the animals with spontaneous infection and in those with experimentally induced disease there were severe morphologic lesions not only in the small intestines, but also in the other viscera and the brain. Catarrhal to hemorrhagic enteritis was observed in 56.5 per cent of the spontaneous cases and 57.1 per cent of the test animals. Parenchymal dystrophy with hemorrhages were seen in the liver in 89.1 per cent of the pigs of the first group and 57.1 per cent of those of the experimental group. Kidney lesions were noted in 65.2 per cent and 28.6 per cent, respectively. Spontaneously affected piglets showed bacterial thrombi in the lumen of some small blood vessels, and in the adrenals (23.9 per cent) and the thymus (13.00 per cent). In the brain there was meningoencephalitis in 54.3 per cent of the spontaneously affected animals and in 85.9 per cent of the experimentally infected ones. In the test animals infected with serotype 0149 there were more serious morphologic changes than in those infected with serotype 0138. It was demonstrated that occasionally pathogenic E. coli organisms had a broader spectrum of action in the body of host sucklings. So colibacteriosis is considered a severe generalised disease which runs its course in sucking pigs as septicaemia and toxaemia.

[Morphological and enzymatic changes in chicks treated with antibiotics]. / Morfologichni i enzimni izmeneniia pri pileta, tretirani s niakoi antibiotitsi.

The live, kidney and skeletal muscules of 54 chickens fed experimentally with bacitrazin, gallimycin, oleandomycin, tetracyclin, tylan, chlornitromycin, streptomycin and penicillin, and of 10 control birds were investigated pathomorphologically and histochemically (succinate--and lactate-dehdrogenase and esterase). Parenchymal dystrophy in the epithelial cells of the liver and kidney and areactive necrotic foci amid the parenchyma were assessed. Dystrophic and necrotic changes observed in the muscle fibres of treated birds. Reduced enzyme activity was proven. The studies indicate that the morphological and enzyme changes in the liver, kidney and skeletal muscules of chickens treated with bacitrazin, gallimycin, chlornitromycin and streptomycin are greater than these observed in birds fed with tylan, tetracyclin, olenadomycin and penicillin. It is proven that the morphological and enzyme changes established in healthy chickens fed with prophylactic antibiotic doses are due to the antibiotics applied.

[Comparative pathomorphological studies of turkeys and hens experimentally infected with Newcastle disease virus]. / Sravnitelni patomorfologichni prouchvaniia pri puiki i kokoshki, eksperimentalno zarazeni s niukiasulski virus.

Comparative pathomorphologic studies were carried out with 40 birds (29 turkeys and 11 hens) infected per os with 0.5 cc embryonal fluid 10(5) ELD 50 each with two Newcastle disease virus strains (Texas -- standard and 7/5 isolated from dead hens and typed as viscerotropic). It was found that the pathoanatomical picture is negative for all birds experimentally infected with the Texas strain. Haemorrhagic necrotic modification of the glandular stomach and intestine were found in birds infected with strain 7/5. The pathoanatomical finding is better expressed in hens compared with that for turkeys. The histologic modification in birds infected with strain Texas were manifested mostly by nonsuppurative encephalitis. Haemorrhagic-diphtheroid inflammation of the alimentary tract, haemorrhages in the viscera and unreactive necrotic foci in the spleen as well as poorly manifested inflammatory changes in the central nervous system were found in birds infected with strain 7/5. No pathoanatomical modifications for Newcastle disease were found in turkeys, analogous to hens, infected with velogenic neurotropic virus. The velogenic viscerotropic strain is less pathogenic for turkeys than for hens. It causes slighter haemorrhagic necrotic modification in turkeys viscera than in hens. Nonsuppurative encephalitis established histologically in both turkeys and hens infected with neurotropic and viscerotropic Newcastle disease virus is a constant finding and may be used as a diagnostic sign of the disease.

[Trial of vaccination against Aujeszky's disease]. / Izpitvane na skhemi za vaksinatsiia sreshtu bolestta na Aueski.

An experiment was carried out on pigs during which a passive immunity was created, similar to the colastral one, by injecting a specific for Aujeszky's disease gamma-globulin. After 48 hours the pigs were vaccinated with different quantities of living MK-25 vaccine and were checked for virus neutralizing antibodies against Aujeszky's disease. On the 90th and 180th days after the vaccination they were infected with a virulent virus (10(6) TCIU) and were checked clinically, serologically, virologically and pathomorphologically. It was proved that the pigs who had a passive immunity and were vaccinated with one dose of vaccine, did not build up a stable and active immunity after their vaccination, due to the neutralization of the vaccinal virus by passive immunity. The implementation of higher quantities of vaccine, however, overcame passive immunity and induced the build-up of active immunity after the vaccination.

[Vaccination in Aujeszky's disease on enzootic fattening farms]. / Vaksinatsiia sreshtu bolestta na Aueski v enzootichni ugoitelni stopanstva.

An experiment was carried out on 125 pigs, originating from immune mothers on an enzootic for A. D. swine-breeding farm. The pigs were vaccinated once and twice with living vaccine MK-25 at different moments after their weaning. On the 180th after the vaccination the pigs were infected with a virulent (10(6) TCID) pseudorabies virus. They were studied clinically, serologically, virologically and pathomorphologically. It was proved that the vaccination of pigs, born by immune mothers, did not bring about the formation of a solid active immunity due to the neutralization of the vaccinal virus by the colostral immunity. A later vaccination of the pigs after the exhaustion of colostral immunity, did not lead to an increased vaccination effect, since during that period met with the persistent virus on the enzootic farm. Re-vaccination, however, created resistance of pigs to infection and a limited persistence of virulent virus.

[Histological and ultrastructural changes in calves infected with bovine herpesvirus 2]. / Khistologichni i ultrastrukturni promeni pri teleta, infektsirani s bovid herpesvirus 2.

We studied the hide, neck knots, as well as the liver of calves infected intradermally with strain KOS-Haskovo of Bovid Herpes Virus 2. On the spot of the injection we found necrotic changes in the superficial strata of the epidermis, hydropic distrophy of St. spinosum and also eosinophil intranuclear inclusions in separate epithelial cells. Intranuclear acidophil inclusions were proved also in the macrophages of the lymph knots, whereas in the liver we found a reactive lithic micronecroses. The ontogenic cycle of development took place in the cytoplasm of the infected cell and during this process the nucleocapsid was formed in the nucleus, whereas the virion was formed in the cytoplasm with the membrane elements. It was proved that changes were due to the virus which has a wide range of alteration in the bodies of the calves.

[Plans for using vaccination in Aujeszky's disease]. / Skhemi za prilozhenie na vaksinatsiia pri bolestta n a Aueski.

A number of clinical, serological, virological and pathomorphological investigations were carried out on pigs bred on a swine-breeding farm, enzootic with regard to AD. One hundred and forty pigs, born by mothers vaccinated with ethanol-saponin vaccine, were inoculated with different quantities of living MK-25 vaccine against AD at the moment of their weaning, as well as on the 15th, 90th and 150th days after the vaccination, were nasally infected in doses 4 cm3 with a virulent/5 x 10(6) CCIU in 1 cm3/virus. No encephalitic clinical symptoms were observed but pathomorphologically was proved a non-suppurative meningoencephalitis with the 1 dose vaccinated pigs, provoked on the 15th day after the vaccination, with those pigs used for control and vaccinated with 1 dose on 90th day and with one control pig on the 180th day. We also proved the presence of lymphohistiocyte interstitial pneumonia as well as intranuclear inclusions in the macrophages of the tonsils. A virus was isolated from the tonsils and from the lungs. Serologically was proved an increase in the titre of antibodies with all test pigs. It was proved that the passively acquired (colostrum) immunity against AD which the pigs, born by vaccinated mothers, possess neutralized the vaccinal virus and prevented the acquisition of an active immunity after vaccination. Its inhibitory action could be overcome by vaccinating with increased quantities of vaccine.