The silverleaf whitefly Bemisia tabaci (Genn.) biotype B (Hemiptera: Aleyrodidae) is an economically important pest of tomatoes Solanum lycopersicum (L.), causing irregular ripening on fruits and ...transmitting several plant pathogenic geminiviruses. The management of this pest is commonly based on repetitive spraying with synthetic pesticides, causing serious environmental damages and increase of resistance by insect population. In the present study, essential oils from the leaves of Artemisia camphorata Vill., Ageratum conyzoides L., Foeniculum vulgare Mill., Lippia alba (Mill.) N. E. Br., Plectranthus neochilus Schltr., and Tagetes erecta L. were investigated for their possible repellent and oviposition-deterrent effects against B. tabaci biotype B on tomato. In a multi-choice assay, P. neochilus essential oil was the most active repellent and oviposition deterrent. Essential oils of A. conyzoides and T. erecta significantly deterred the female B. tabaci biotype B from laying eggs on treated tomato leaflets compared with the control. (E)-Caryophyllene (30.67 %) and the monoterpenes α-pinene (15.02 %) and α-thujene (11.70 %) were identified as the major constituents of the essential oil of P. neochilus. Our findings demonstrated the potential of essential oil of P. neochilus and other oils in the reduction of settlement and oviposition of B. tabaci biotype B on tomato.
The sweet potato whitefly,
Bemisia tabaci
Gennadius biotype B (Hemiptera: Aleyrodidae), causes high economic losses in vegetables, beans, soybeans, peanuts, cotton, and several ornamental plants. ...Repeated spray applications of synthetic pesticides has led
B. tabaci
to develop resistance to numerous conventional insecticides, besides polluting the environment. In this work, we investigated the bioactivity of the essential oil of
Pelargonium graveolens
L’Her (Geraniaceae) (PG-EO) and some related monoterpenes against the sweet potato whitefly
Bemisia tabaci
Gennadius biotype B (Homoptera: Aleyrodidae) in tomato. This oil significantly reduced the number of
B. tabaci
adults on tomato leaflets. The deterrence experiments showed similar results for PG-EO, geraniol, and citronellol; however, citronellol was more effective than PG-EO. In fumigation tests, the essential oil of
P. graveolens
caused 100 % mortality of adults of
B. tabaci
biotype B at concentrations from 0.5 μL L
−1
in air. The vapor toxicity of geraniol, linalool, and citronellol, the main chemical constituents of the essential oil of
P. graveolens
(PG-EO), was similar to that of PG-EO. These results suggest that PG-EO and its related monoterpenes are potentially applicable to develop effective natural product-based pest-management compounds.
Bemisia tabaci
(Gennadius) (Hemiptera: Aleyrodidae) Middle East Asia Minor 1 is one of the most important pests of the common bean, due to its potential of causing direct and indirect damage. This ...study aimed to evaluate 78 bean genotypes to verify the occurrence of resistance of antixenosis type against
B. tabaci
. Initially, multiple-choice trials were performed to evaluate the oviposition preference and nymphs’ establishment at 3 and 15 days after infestation. Subsequently, 21 bean genotypes were selected, and a no-choice test was conducted. Colorimetric analyses were performed to establish correlations between leaf color and insect establishment. In multiple-choice trial, the genotypes BRS Ametista, BRS Estilo, BRS Esplendor, SCS 204 Predileto, BRS Notável, IPR Eldorado, CHIB 06, IPR Quero-Quero, Iapar 81, CHIP 338, IPR Garça, Arcelina 4, SCS 202 Guará, IAC Esperança, H96102-1-1-1-52, CHIP 348, Carioca Comum, CHIP 300, IAC Carioca Eté, IAC Ybaté, and Tybatã were the least used for oviposition and nymph establishment, demonstrating antixenosis or antibiosis. In the no-choice trial, most genotypes were less attractive to whitefly, and the genotypes CHIB 06, IPR Garça, CHIP 300, and IAC Esperança had less oviposition. The most attractive genotypes presented high luminosity and more intense green and yellow colors, indicating positive correlation. Therefore, the genotypes BRS Ametista, SCS 204 Predileto, BRS Estilo, IPR Eldorado, SCS-202 Guará, Carioca Comum, Arcelina 4, CHIP 348, and IAC Esperança showed the highest resistance stability in the no-choice trial, and they are promising sources of antixenotic factors for use in breeding programs to obtain whitefly-resistant common bean lines.
A procedure is proposed for the determination of the vapor concentration of 2,4,6-trinitrotoluene (TNT) in air at a level of 10
–16
g/cm
3
in the control of objects for the presence of TNT. The ...procedure includes preconcentration of TNT vapors and gas chromatographic determination with a limit of TNT detection at a level of 0.08 ± 0.02 pg in a sample. The procedure was applied to the control objects in cells of typical automatic luggage locker with sampling through sampling air ducts. A measure of sample losses as the breakthrough of vapors through sampling air ducts and gas dynamic conditions for the reduction of vapor losses as the ratio of diffusion coefficient to the air duct flow rate were proposed. The time constant of the saturation of the sampling system with TNT vapors and the time constant of its cleaning were determined. It was shown that TNT vapors can be detected virtually satisfactorily near TNT-containing objects with sampling through long channels.
The silverleaf whitefly
Bemisia tabaci
(Genn.) biotype B (Hemiptera: Aleyrodidae) is one of the most severe tomato pests in the world. The damage caused by this insect may compromise up to 100% of ...crop production, and management of this pest has relied on spraying of synthetic insecticides. However, due to the environmental issues associated with this practice, alternative methods such as the use of botanical pesticides are now used as a strategy of integrated pest management (IPM). We evaluated the effects of essential oils of five plant species on
B. tabaci
biotype B in tomato and demonstrate that the essential oils (0.5%) of
Piper callosum
(PC-EO),
Adenocalymma alliaceum
(AA-EO),
Pelargonium graveolens
(PG-EO), and
Plectranthus neochilus
(PN-EO) inhibit the settlement and oviposition of
B. tabaci
biotype B adults in tomato plants. In fumigation tests,
A. alliaceum
(AA-EO) at 0.4 μL/L of air after 72 h and 0.1 μL/L of air after 6 h was the most effective against nymphs and adults of
B. tabaci
biotype B, respectively. The major chemical constituents of PC-EO were identified as being safrole (29.3%), α-pinene (19.2%), and β-pinene (14.3%), whereas diallyl trisulfide (66.9%) and diallyl disulfide (23.3%) were the major compounds identified in AA-EO. This is the first report on the reduction of oviposition by the use of
P. callosum
(PC-EO) and
A. alliaceum
(AA-EO). In addition, the fumigant effect of
A. alliaceum
(AA-EO) on nymphs and adults has also been reported here for the first time.
Bemisia tabaci
(Gennadius) biotype B (Hemiptera: Aleyrodidae) has developed resistance to numerous conventional insecticides, which has led us to investigate the toxicity of ten dihydrobenzofuran- ...(DBN) and benzofuran-type (BN) neolignans structurally related to conocarpan against second instar
B. tabaci
nymphs. At concentrations higher than 5 mg/L, most of the tested compounds killed 100% of
B. tabaci
biotype B nymphs 6 days after spraying. The contact toxicity of compounds
2
((±)-
trans
-dehydrodiferulate dimethyl ester),
3
((±)-4-
O
-methyl-
trans
-dehydrodiferulate dimethyl ester),
5
((±)-4-
O
-acetyl-
trans
-dehydrodiferulate dimethyl ester),
6
((±)-7′,8′-dihydro-
trans
-dehydrodicoumarate dimethyl ester),
8
((±)-4-
O
-methyl-7′,8′-dihydro-
trans
-dehydrodiferulate dimethyl ester), and
10
((±)-7′,8′-dihydro-7,8-dehydro-
trans
-dehydrodicoumarate dimethyl ester) was higher than the contact toxicity of pyriproxyfen at a concentration of 75 mg/L, which was used as positive control. Repellent (compounds
2
and
7
((±)-7′,8′-dihydro-
trans
-dehydrodiferulate dimethyl ester) and oviposition deterrent (compounds
2
,
3
, and
7
) effects were observed for adult whiteflies exposed to leaves sprayed with DBNs for 24 and 48 h, respectively. These results suggest that DBNs have potential application in the development of effective pest management compounds.
To determine predisposing factors of idiopathic allograft fibrosis among pediatric liver transplant recipients.
Protocol biopsies (PB) from stable liver transplant (LT) recipient children frequently ...exhibit idiopathic fibrosis. The relation between allograft inflammation, humoral immune response and fibrosis is uncertain. Also the role of HLA-DRB1 genotype has not been evaluated, though it's associated with fibrosis in autoimmune hepatitis.
This observational study, included 89 stable LT recipient transplanted between 2004–2012 with mean follow-up of 4.3years, 281 serial PBs (3.1 biopsy/child) and human leukocyte antigen (HLA) antibody data. PBs were taken 1–2, 2–3, 3–5, 5–7, and 7–10years post-LT, and evaluated for inflammation and fibrosis using liver allograft fibrosis score (LAFSc). The evolution of fibrosis, inflammation and related predisposing factors were analysed.
HLA-DRB1*03/04 allele and Class II DSA were significantly associated with portal fibrosis (p=0.03; p=0.03, respectively). Portal inflammation was predisposed by Class II DSA (p=0.02) and non-HLA antibody presence (p=0.01). Non-portal fibrosis wasn't predisposed by inflammation. Lobular inflammation was associated with non-HLA antibodies.
We conclusively demonstrated that allograft inflammation results in fibrosis and is associated with post-LT Class II DSA and non-HLA antibodies. The HLA-DRB1*03/04 allele caused genetic predisposition for fibrosis.
None.
•There is a link between genetic predisposition, alloimmune antibodies, allograft inflammation and fibrosis•Description of allograft natural history by assessing evolution of inflammation, fibrosis in different histological zones•Allograft inflammation results in allograft fibrosis and is associated with post-LT Class II DSA and non-HLA antibodies•The HLA-DRB1*03/04 allele causes genetic predisposition for fibrosis
Among pediatric liver transplant recipients, the graft longevity is expected to parallel the life expectancy of the recipient. A major impediment in this is progressive allograft fibrosis, the cause of which is not well understood. If this pathogenesis could be found, then interventions to arrest the progressive fibrosis could be explored. In our 89 patients for whom we did periodic surveillance liver biopsies, inflammation was found to precede the fibrosis and associated with presence of specific antibodies. Certain genetic predisposition for higher fibrogenesis was also found, thus establishing a link between genetic predisposition, alloimmune response, inflammation, and allograft fibrosis.
The NICA accelerator complex includes beam transfer lines and stations for applied research. The first commissioning of the Station of Chip Irradiation (SOCHI) was performed at the end of 2021with С
...4+
heavy ions extracted from the linear accelerator (HILAC) at an energy of 3.2 MeV/n. The new SOCHI beam transfer line is integrated in the existing HILAC-Booster beamline. The Irradiation Setup for Components of Radioelectronic Apparatus (ISCRA) with ion energy ranging from 150 to 500 MeV/n and the Setup for Investigation of Medical Biological Objects (SIMBO) with the ion energy ranging from 400 to1100 MeV/n are based on the beams extracted from Nuclotron. The equipment of ISCRA and SIMBO stations has been manufactured and is planned to mount in the end of 2022. The beamlines are being designed now. The technical parameters of the beamlines and stations and the results of the first run of the SOCHI station are presented in this study.
The common bean Phaseolus vulgaris L. (Fabaceae) is an important vegetable protein source and constitutes a significant part of the diet in many tropical countries. The Mexican bean weevil Zabrotes ...subfasciatus (Boheman) (Coleoptera: Bruchidae) is one of the main pests affecting stored beans: it causes extensive qualitative and quantitative grain loss. We investigated the bioactivity of the essential oils extracted from Chenopodium ambrosioides L. (CA-EO), Ocimum gratissimum L. (OG-EO), and Schinus terebinthifolius Raddi (ST-EO) against Z. subfasciatus. After 12-h treatment, CA-EO and OG-EO at 20.0 μL/L of air killed 100% Z. subfasciatus, whereas ST-EO at 100.0 μL/L of air afforded 100% Z. subfasciatus mortality after 24 h. CA-EO provided the lowest 24 h LD50 (0.8 μL/L of air) and displayed efficient repellent activity against Z. subfasciatus. Our results demonstrate that CA-EO is a potentially economical and environmentally friendly alternative to manage Z. subfasciatus in stored beans.
•All the tested essential oils kill 100% Zabrotes subfasciatus.•The C. ambrosioides essential oil has repellent activity against Z. subfasciatus.•The investigated essential oils could act as natural insecticides in stored grains.
Using the 1.32 Formula omitted statistics collected at the Formula omitted peak with the KEDR detector at the VEPP-4M Formula omittedcollider, we measured the branching fractions of Formula omitted ...meson decays to the final states 2( Formula omitted, Formula omitted, 2( Formula omitted and Formula omitted. The results obtained for the decays Formula omitted2( Formula omitted, Formula omitted contradict the measurements performed by other groups in the last century, but agree well with recent results of BABAR and BESIII collaborations.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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