[en] The production of τ pairs in γγ collisions is studied with the L3 detector at LEP. Data were collected at √s = 189 - 208 GeV for a total integrated luminosity of 608.1 pb^-1. An exclusive decay channel is considered, with τ^± → e^±v_τv_e and τ^-+ → ρ^-+v_τ, with ρ^-+ → π^-+π⁰. The cross section σ(e⁺e^- → e⁺e^-τ⁺τ^-) is compared to Ο(α⁴) QED calculations. The cross section of τ production is measured in γγ collisions for the first time at LEP 2. (author)

[en] The production of quarkonium states at high energy provides quite stringent test of our understanding of both short-distance and long-distance aspects of quantum chromodynamics. In this article we review the status of charmonium and bottomonium production at LEP. (orig.)

[en] Double tag events in two photon collisions are studied using the L3 detector at the LEP center of mass energies √s ≅ 189 - 202 GeV. The cross-section of γ^*γ^* collisions is measured at an average photon virtuality < Q²> =15 GeV². The results are in agreement with Monte Carlo predictions based on perturbative QCD, while the Quark Parton Model alone is insufficient to describe the data. The measurements are compared to the LO and the NLO BFKL calculations. (author)

[en] The first LEP result on the inclusive χ_c1 production in Z decays observed via the decay mode χ_c1 → J/ψ + γ, where J/ψ is reconstructed in its leptonic decay mode J/ψ → μ⁺μ^-. Assuming that there are no χ-c-0 and χ_c2 produced, the Branching ratio Br(Z → χ_c1 + X) has been determined and the branching ratio Br(b → J/ψ + X) has been updated. 2 figs., 12 refs

[en] Samples of 13 species of forest tree leaves growing in the semi-hilly arid zone of Punjab State in India were collected at 30 day intervals over 12 months, in order to assess their nutritional value for livestock. The ground samples were pooled for four seasons: dry hot, hot humid, fall, and winter. The data were arranged in a 13 x 4 factorial design for analysis. For tannin fractionation, leaves of 12 species containing more than 3.5% total phenols were selected and data were analysed within a 12 x 12 factorial design. The chemical composition, irrespective of the season, revealed that Leucaena had the highest crude protein (CP, 220 g/kg dry matter). Globulin was the major protein fraction in most of the leaves. The lowest concentration of neutral detergent fibre (NDF) was in Morus, Acacia and Grewea spp. Fibre and lignin content increased during the fall and winter. The leaves of Grewea, Morus, Leucaena, Carrisa and Acacia were rich in Ca, P and most of the trace elements. The total phenolics ranged between 38 (Toona) and 169 g/kg DM (Anogeisus). The leaves of Anogeisus had the highest concentration of hydrolysable tannins (16.9%) whereas those of Carrisa had highest condensed tannins (4.6%). The condensed tannins (>3%) were negatively correlated to the digestibility of dry matter (DM), NDF and CP. The digestion kinetic parameters for DM, NDF and CP revealed that leaves of Morus alba, Zizyphus and Ehretia were most degradable. The minimum rumen fill values also revealed that leaves of Grewea, Azadirachta, Morus, Ehretia and Leucaena had higher potential for voluntary DM intake, especially compared to leaves of Ougeinia, Zizyphus xylopyrus, Dodonea and Carrisa. During winter, most of the leaves had a low potentially degradable fraction, with a low rate of degradation. Screening leaves by the in vitro gas production technique suggested that leaves of Melia azedarach, Azadirachta indica, Morus alba and Leucaena leucocephala were potential feeds for ruminants. Nutritional value of Toona ciliata, Morus alba, Melia azedarach and Leucaena leucocephala was assessed in vivo in bucks. The excretion of purine derivatives, in the urine and, therefore, microbial protein synthesis, was greatest in bucks receiving Melia azedarach. The leaves of Melia azedarach, Morus alba and Leucaena leucocephala supplemented with a mineral mixture and common salt could be fed as a complete feed for small ruminants. It was concluded that the leaves of Morus, Ehretia, Grewea, Melia azedarach and Leucaena had great potential as livestock feed, while feeding of Ougeinia, Zizyphus and Dodonea leaves should be avoided. (author)

[en] A new first-level trigger for the L3 experiment at LEP (CERN) is presented. It uses the inner time expansion chamber of the detector, which is not until now used for triggering. The event selection presented here is based on identifying sectors containing genuine tracks originating from the interaction point. The system is capable of identifying both single tracks and hadronic jets in a sector. The sector identification used a neural network algorithm. The hardware for the event selection is built around the existing custom-made neural network digital modules. Events are classified in less than 100 ns and the final rate of accepted events is 1-3 Hz starting from a beam-crossing rate of 45 kHz. (orig.)

[en] This study was taken up to assess the impact of supplementing herbal feed additives [HFAs; fruit of Myristica fragrans (Jayphall), seeds of Anethum sowa (Suva), fruit of Apium graveolens (Ajmo), fruit of Cuminum cyminum (Jeera), bark of Cinnamonum zeylanicum (Dalchini), or whole plant of Eclipta alba (Bhangro)] containing essential oils as active component on the nutrient utilization and methane production using wheat straw–based total mixed ration (TMR) as a substrate by in vitro gas production technique. The essential oil content was the highest (P < 0.01) in M. fragrans followed by E. alba and A. sowa. In addition to essential oils, these HFAs also contained saponins, tannins, and antioxidants. The HFAs were supplemented at 1–3% of substrate dry matter (DM). The data were analyzed by 6 × 4 factorial design. Irrespective of level of HFA, the net gas production (NGP) and metabolizable energy (ME) availability was the highest (P < 0.01) in TMR supplemented with C. zeylanicum comparable with E. alba, but higher than TMR supplemented with other HFAs. Supplementation of TMR with different HFAs did not affect the digestibility of neutral detergent fiber (NDF) and true organic matter (TOM) and partitioning factor (PF). The total volatile fatty acids (VFAs), acetate, propionate (P < 0.01), and butyrate (P < 0.05) production was the highest in TMR supplemented with A. sowa, and the lowest was observed in TMR supplemented with C. cyminum. The isobutyrate and valerate production was also the highest (P < 0.01) in diet supplemented with A. sowa, but isovalerate production was the highest (P < 0.01) in diet supplemented with C. zeylanicum. The A:P ratio was the best in TMR supplemented with A. sowa. The efficiency of rumen fermentation was the highest, and efficiency of conversion of hexose to methane was the lowest in diet supplemented with A. sowa as compared to all other supplements. The in vitro methane production expressed as either percent of NGP, ml/100 mg DM of substrate/24 h, or as ml/100 mg of digestible OM/24 h was the lowest in TMR supplemented with A. sowa. The ammonia nitrogen production from TMR supplemented with M. fragrans and A. sowa was comparable, but significantly (P < 0.01) lower than TMR supplemented with other HFAs. Irrespective of the nature of HFA, the NGP and ME availability were significantly (P < 0.01) higher in TMR supplemented with HFAs at all levels as compared to un-supplemented TMR. As compared to control, the digestibility of NDF and that of TOM was depressed slightly in all the HFA-supplemented TMRs. The supplementation of HFAs at 2% of substrate DM improved (P < 0.01) the production of total VFAs, acetate, and propionate, and that of isovalerate in comparison to the un-supplemented TMR. The acetate to propionate ratio increased (P < 0.01) with the increase in the level of supplementation of HFAs containing essential oils. The methane and ammonia productions were depressed significantly when TMR was supplemented at 2% level of HFAs as compared to control TMR. It was concluded that supplementation of TMR with A. sowa at 2% of substrate was fermented better as indicated by the production of total and individual VFA, methane, and ammonia as compared to TMR supplemented with other HFA or un-supplemented TMR.

[en] Chaffed cauliflower leaves (CL), fruit waste (FJW), after juice extraction, or a mixture of CL and FJW in a 1 : 1 ratio were each ensiled, either alone or after mixing with either wheat straw, rice straw or berseem straw in 70 : 30 mixtures. The chemical composition of cauliflower leaves, fruit juice waste and the 1 : 1 combination of the two revealed that these wastes had a high crude protein (CP) content, and low neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents, indicating their potential as alternative feedstuffs for dairy cattle. The ensiling of the fruit and vegetable wastes resulted in a significant depression in the net gas production and digestibility of nutrients. The per cent decrease in net gas production, NDF and organic matter (OM) digestibility varied from 26.3 to 50.8%, 26.3 - 47.7% and 19.4 - 22.5%, respectively. The NDF, ADF, and cellulose contents were increased, when CL, FJW and CL-FJW were ensiled with straw (either of the straws), by 84, 77 and 71%; 51, 35 and 54% and 69, 48 and 37%, respectively in ensiled CL, FJW and CL-FJW. Maximum (P <0.05) net gas production and OM digestibility was observed in the ensiled FJW, irrespective of the source of added straw. The digestibility of NDF was observed to be highest in ensiled CL-FJW, irrespective of the straw combination. Amongst the straws, the ensiled wheat straw, irrespective of the combination of fruit and vegetable waste, resulted in maximum net gas production and digestibility of nutrients. (author)

[en] We have compared a new model used in GEANT4 for multiple scattering and the model based in the Moliere theory used in GEANT3 with the data collected in the L3 detector for the case of muons of momentum around 45 GeV. We have found some disagreement in the case of GEANT3 but a good matching to the data in the case of GEANT4. (orig.)

[en] The isotopic composition of our Solar System reflects the blending of materials derived from numerous past nucleosynthetic events, each characterized by a distinct isotopic signature. We show that the isotopic compositions of elements spanning a large mass range in the earliest formed solids in our Solar System, calcium–aluminum-rich inclusions (CAIs), are uniform, and yet distinct from the average Solar System composition. Relative to younger objects in the Solar System, CAIs contain positive r-process anomalies in isotopes A < 140 and negative r-process anomalies in isotopes A > 140. This fundamental difference in the isotopic character of CAIs around mass 140 necessitates (i) the existence of multiple sources for r-process nucleosynthesis and (ii) the injection of supernova material into a reservoir untapped by CAIs. A scenario of late supernova injection into the protoplanetary disk is consistent with formation of our Solar System in an active star-forming region of the galaxy.