371 research outputs found
Feeding in the adult of Hermetia illucens (Diptera Stratiomyidae): reality or fiction?
Hermetia illucens(L.) (Diptera Stratiomyidae) is a promising species as alternative protein source for animal feed, able to convert a wide range of organic materials. The knowledge on larval biology, development, nutritional needs, and nutritional composition is rich, while few information is available on adult traits. The aim of the present study was to investigate the influence of the adult nutrition on the survival, the longevity and the ovaries development of H. illucens. In detail, three food sources have been compared to starvation. Water, a sucrose solution and a protein solution were given to new emerged adults and data on longevity and ovary development were acquired. Trials were conducted on single specimen and on a cohort of adults. In all the trials, starved adults survived significantly shorter than all other thesis. When adults were maintained isolated, the survival was significantly influenced by the nourishment: longevity was longer when adults were feed with a sucrose solution, while the supply of a protein source provideda lifespan significantly higher than starvation but similar to water or to sucrose solution. In cages longevity was always shorter than in isolated adults for both males and females and the overall trend was similar to single individual trials with the exception of protein solution. Ovary development of females under different nourishment did not show differences.More studies are necessary to identify a correct nutritionconsideringthe integration of different chemical compounds to obtain optimal adult performancein terms of longevity and reproduction
Growth performance of the black soldier fly (Hermetia illucens) on by-products from brewing production
Hermetia illucens (Diptera: Stratiomyidae), also known as the black soldier fly, is considered an interesting candidate
as alternative source of protein for livestock. Larvae of this species are able to efficiently bio-convert organic waste
material into insect biomass. In addition, larvae can consume twice of their weight per day of waste, accumulating high
amounts of protein and fat. The choice of the correct rearing substrate is essential in order to contribute to the disposal
of waste or by-products obtained from the various stages of the industrial food production, that could hardly find other
utilization, and to maximize the production of black soldier fly prepupae. Moreover, it is important to identify a lowcost
diet with no competition with animal or human consumption. Among numerous by-products of vegetal origin,
in this study black soldier fly larvae were reared on the following substrates originating from the brewing production:
brewer\u2019s spent grain, trub, and a mix of the two by-products (50 and 50%). The influence of the rearing substrates of the
different life-history traits was observed. In particular, we considered the survivorship of the different developmental
stages, the larval final weight, the duration of the larval period and the emergence of adults. Larvae could complete their
development on the three substrates tested. Nevertheless, some differences were observed on the different parameters.
In particular, the mixture of the two by-products resulted in a faster growth of the larvae that took less days to reach
prepupal stage than the ones grown on the single by-product. The same trend was noticed on the final larval weight.
The mortality of the larvae was significantly higher on those grown on brewer\u2019s spent grain, while no differences were
noticed among the other substrates. This study showed the possibility to rear the black soldier fly on different byproducts
coming from the brewing production industry, that can therefore represent an interesting rearing substrate
for the insect. More research is needed to optimize the diet for a possible use in mass rearing system
Pre-operative radiochemotherapy with raltitrexed for resectable locally-advanced rectal cancer : a phase II study
Background: The aim of the study was to evaluate the response to and toxicity of pre-operative radiochemotherapy containing raltitrexed (Tomudex) for resectable rectal adenocarcinoma. Patients and Methods: From November 2000 to June 2002, 18 consecutive patients staged T3 N0/N+ were treated with pre-operative chemotherapy (3 mg/m 2 of raltitrexed on days 1, 19, 38) and concurrent radiotherapy (RT) (50.4 Gy) in 6 weeks, followed by radical surgery within 8 weeks. Results: The treatment compliance was high. No major acute toxicity was reported. Concerning late toxicity, genitourinary adverse effects were prevalent. A complete response was observed in one patient (6%), partial response in eight (47%), stable disease in seven (41%) and progression in one case. Three-year actuarial disease-free and overall survival rates were 37% and 87.5%, respectively. Conclusion: Raltitrexed did not increase the pathological response rate compared with the rates obtained with use of preoperative RT alone and reported in the literature. Acute morbidity was low and acceptable, while late toxicity was considerable, prevalently concerning sexual dysfunction and urinary complications
Existence and uniqueness of global solutions to fully nonlinear second order elliptic systems
We consider the problem of existence and uniqueness of strong a.e. solutions u:Rnâ¶RNu:Rnâ¶RN to the fully nonlinear PDE system
F(â
,D2u)=f, a.e. on Rn,(1)
F(â
,D2u)=f, a.e. on Rn,(1)
when fâL2(Rn)NfâL2(Rn)N and F is a CarathĂ©odory map. (1) has not been considered before. The case of bounded domains has been studied by several authors, firstly by Campanato and under Campanatoâs ellipticity condition on F. By introducing a new much weaker notion of ellipticity, we prove solvability of (1) in a tailored Sobolev âenergyâ space and a uniqueness estimate. The proof is based on the solvability of the linearised problem by Fourier transform methods, together with a âperturbation deviceâ which allows to use Campanatoâs near operators. We also discuss our hypothesis via counterexamples and give a stability theorem of strong global solutions for systems of the form (1)
Measurement of the B0-anti-B0-Oscillation Frequency with Inclusive Dilepton Events
The - oscillation frequency has been measured with a sample of
23 million \B\bar B pairs collected with the BABAR detector at the PEP-II
asymmetric B Factory at SLAC. In this sample, we select events in which both B
mesons decay semileptonically and use the charge of the leptons to identify the
flavor of each B meson. A simultaneous fit to the decay time difference
distributions for opposite- and same-sign dilepton events gives ps.Comment: 7 pages, 1 figure, submitted to Physical Review Letter
Production of Single W Bosons at \sqrt{s}=189 GeV and Measurement of WWgamma Gauge Couplings
Single W boson production in electron-positron collisions is studied with the
L3 detector at LEP. The data sample collected at a centre-of-mass energy of
\sqrt{s} = 188.7GeV corresponds to an integrated luminosity of 176.4pb^-1.
Events with a single energetic lepton or two acoplanar hadronic jets are
selected. Within phase-space cuts, the total cross-section is measured to be
0.53 +/- 0.12 +/- 0.03 pb, consistent with the Standard Model expectation.
Including our single W boson results obtained at lower \sqrt{s}, the WWgamma
gauge couplings kappa_gamma and lambda_gamma are determined to be kappa_gamma =
0.93 +/- 0.16 +/- 0.09 and lambda_gamma = -0.31 +0.68 -0.19 +/- 0.13
Search for an invisibly decaying Higgs boson in e^+e^- collisions at \sqrt{s} = 183 - 189 GeV
A search for a Higgs boson decaying into invisible particles is performed
using the data collected at LEP by the L3 experiment at centre-of-mass energies
of 183 GeV and 189 GeV. The integrated luminosities are respectively 55.3 pb^-1
and 176.4 pb^-1. The observed candidates are consistent with the expectations
from Standard Model processes. In the hypothesis that the production cross
section of this Higgs boson equals the Standard Model one and the branching
ratio into invisible particles is 100%, a lower mass limit of 89.2 GeV is set
at 95% confidence level
Search for Neutral Higgs Bosons of the Minimal Supersymmetric Standard Model in e+e- Interactions at \sqrt{s} = 189 GeV
A search for the lightest neutral scalar and neutral pseudoscalar Higgs
bosons in the Minimal Supersymmetric Standard Model is performed using 176.4
pb^-1 of integrated luminosity collected by L3 at a center-of-mass energy of
189 GeV. No signal is observed, and the data are consistent with the expected
Standard Model background. Lower limits on the masses of the lightest neutral
scalar and pseudoscalar Higgs bosons are given as a function of tan(beta).
Lower mass limits for tan(beta)>1 are set at the 95% confidence level to be m_h
> 77.1 GeV and m_A > 77.1 GeV
Measurement of the Lifetime of the Tau Lepton
The tau lepton lifetime is measured with the L3 detector at LEP using the
complete data taken at centre-of-mass energies around the Z pole resulting in
tau_tau = 293.2 +/- 2.0 (stat) +/- 1.5 (syst) fs. The comparison of this result
with the muon lifetime supports lepton universality of the weak charged current
at the level of six per mille. Assuming lepton universality, the value of the
strong coupling constant, alpha_s is found to be alpha_s(m_tau^2) = 0.319 +/-
0.015(exp.) +/- 0.014 (theory)
Search for Extra Dimensions in Boson and Fermion Pair Production in e+e- Interactions at LEP
Extra spatial dimensions are proposed by recent theories that postulate the
scale of gravity to be of the same order as the electroweak scale. A sizeable
interaction between gravitons and Standard Model particles is then predicted.
Effects of these new interactions in boson and fermion pair production are
searched for in the data sample collected at centre-of-mass energies above the
Z pole by the L3 detector at LEP. In addition, the direct production of a
graviton associated with a Z boson is investigated. No statistically
significant hints for the existence of these effects are found and lower limits
in excess of 1 TeV are derived on the scale of this new theory of gravity
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