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1.
Phys Rev Lett ; 133(13): 131801, 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39392959

ABSTRACT

We measure the complete set of angular coefficients J_{i} for exclusive B[over ¯]→D^{*}ℓν[over ¯]_{ℓ} decays (ℓ=e, µ). Our analysis uses the full 711 fb^{-1} Belle dataset with hadronic tag-side reconstruction. The results allow us to extract the form factors describing the B[over ¯]→D^{*} transition and the Cabibbo-Kobayashi-Maskawa matrix element |V_{cb}|. Using recent lattice QCD calculations for the hadronic form factors, we find |V_{cb}|=(40.7±0.7)×10^{-3} using the Boyd-Grinstein-Lebed parametrization, compatible with determinations from inclusive semileptonic decays. We search for lepton flavor universality violation as a function of the hadronic recoil parameter w and investigate the differences of the electron and muon angular distributions. We find no deviation from standard model expectations.

2.
Phys Rev Lett ; 133(7): 071802, 2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39213574

ABSTRACT

We report the results of the first search for B^{-} decays to the Ξ[over ¯]_{c}^{0}Λ[over ¯]_{c}^{-} final state using 711 fb^{-1} of data collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The results are interpreted in terms of both direct baryon-number-violating B^{-} decay and Ξ_{c}^{0}-Ξ[over ¯]_{c}^{0} oscillations which follow the standard model decay B^{-}→Ξ_{c}^{0}Λ[over ¯]_{c}^{-}. We observe no evidence for baryon number violation and set the 95% confidence-level upper limits on the ratio of baryon-number-violating and standard model branching fractions B(B^{-}→Ξ[over ¯]_{c}^{0}Λ[over ¯]_{c}^{-})/B(B^{-}→Ξ_{c}^{0}Λ[over ¯]_{c}^{-}) to be <2.7% and on the effective angular frequency of mixing ω in Ξ_{c}^{0}-Ξ[over ¯]_{c}^{0} oscillations to be <0.76 ps^{-1} (equivalent to τ_{mix}>1.3 ps).

3.
Phys Rev Lett ; 128(14): 142005, 2022 Apr 08.
Article in English | MEDLINE | ID: mdl-35476485

ABSTRACT

The measurement of two-particle angular correlation functions in high-multiplicity e^{+}e^{-} collisions at sqrt[s]=10.52 GeV is reported. In this study, the 89.5 fb^{-1} of hadronic e^{+}e^{-} annihilation data collected by the Belle detector at KEKB are used. Two-particle angular correlation functions are measured in the full relative azimuthal angle (Δϕ) and three units of pseudorapidity (Δη), defined by either the electron beam axis or the event-shape thrust axis, and are studied as a function of charged-particle multiplicity. The measurement in the thrust axis analysis, with mostly outgoing quark pairs determining the reference axis, is sensitive to the region of additional soft gluon emissions. No significant anisotropic collective behavior is observed with either coordinate analyses. Near-side jet correlations appear to be absent in the thrust axis analysis. The measurements are compared to predictions from various event generators and are expected to provide new constraints to the phenomenological models in the low-energy regime.

4.
Arch Virol ; 167(5): 1257-1268, 2022 May.
Article in English | MEDLINE | ID: mdl-35353206

ABSTRACT

OBJECTIVE: In this study, we investigated the occurrence of papillomavirus (PV) infection in non-human primates (NHPs) in northeastern Argentina. We also explored their evolutionary history and evaluated the co-speciation hypothesis in the context of primate evolution. METHODS: We obtained DNA samples from 57 individuals belonging to wild and captive populations of Alouatta caraya, Sapajus nigritus, and Sapajus cay. We assessed PV infection by PCR amplification with the CUT primer system and sequencing of 337 bp (112 amino acids) of the L1 gene. The viral sequences were analyzed by phylogenetic and Bayesian coalescence methods to estimate the time to the most common recent ancestor (tMRCA) using BEAST, v1.4.8 software. We evaluated viral/host tree congruence with TreeMap v3.0. RESULTS: We identified two novel putative PV sequences of the genus Gammapapillomavirus in Sapajus spp. and Alouatta caraya (SPV1 and AcPV1, respectively). The tMRCA of SPV1 was estimated to be 11,941,682 years before present (ybp), and that of AcPV1 was 46,638,071 ybp, both before the coalescence times of their hosts (6.4 million years ago [MYA] and 6.8 MYA, respectively). Based on the comparison of primate and viral phylogenies, we found that the PV tree was no more congruent with the host tree than a random tree would be (P > 0.05), thus allowing us to reject the model of virus-host coevolution. CONCLUSION: This study presents the first evidence of PV infection in platyrrhine species from Argentina, expands the range of described hosts for these viruses, and suggests new scenarios for their origin and dispersal.


Subject(s)
Alouatta , Sapajus , Viruses, Unclassified , Animals , Argentina/epidemiology , Bayes Theorem , Papillomaviridae/genetics , Phylogeny , Platyrrhini
5.
Phys Rev Lett ; 126(12): 122001, 2021 Mar 26.
Article in English | MEDLINE | ID: mdl-33834793

ABSTRACT

We report the first evidence for X(3872) production in two-photon interactions by tagging either the electron or the positron in the final state, exploring the highly virtual photon region. The search is performed in e^{+}e^{-}→e^{+}e^{-}J/ψπ^{+}π^{-}, using 825 fb^{-1} of data collected by the Belle detector operated at the KEKB e^{+}e^{-} collider. We observe three X(3872) candidates, where the expected background is 0.11±0.10 events, with a significance of 3.2σ. We obtain an estimated value for Γ[over ˜]_{γγ}B(X(3872)→J/ψπ^{+}π^{-}) assuming the Q^{2} dependence predicted by a cc[over ¯] meson model, where -Q^{2} is the invariant mass squared of the virtual photon. No X(3915)→J/ψπ^{+}π^{-} candidates are found.

6.
Phys Rev Lett ; 126(16): 161801, 2021 Apr 23.
Article in English | MEDLINE | ID: mdl-33961476

ABSTRACT

We present a measurement of R_{K^{*}}, the branching fraction ratio B(B→K^{*}µ^{+}µ^{-})/B(B→K^{*}e^{+}e^{-}), for both charged and neutral B mesons. The ratio for the charged case R_{K^{*+}} is the first measurement ever performed. In addition, we report absolute branching fractions for the individual modes in bins of the squared dilepton invariant mass q^{2}. The analysis is based on a data sample of 711 fb^{-1}, containing 772×10^{6} BB[over ¯] events, recorded at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The obtained results are consistent with standard model expectations.

7.
Phys Rev Lett ; 127(12): 121803, 2021 Sep 17.
Article in English | MEDLINE | ID: mdl-34597085

ABSTRACT

Using data samples of 89.5 and 711 fb^{-1} recorded at energies of sqrt[s]=10.52 and 10.58 GeV, respectively, with the Belle detector at the KEKB e^{+}e^{-} collider, we report measurements of branching fractions of semileptonic decays Ξ_{c}^{0}→Ξ^{-}ℓ^{+}ν_{ℓ} (ℓ=e or µ) and the CP-asymmetry parameter of Ξ_{c}^{0}→Ξ^{-}π^{+} decay. The branching fractions are measured to be B(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})=(1.31±0.04±0.07±0.38)% and B(Ξ_{c}^{0}→Ξ^{-}µ^{+}ν_{µ})=(1.27±0.06±0.10±0.37)%, and the decay parameter α_{Ξπ} is measured to be 0.63±0.03±0.01 with much improved precision compared with the current world average. The corresponding ratio B(Ξ_{c}^{0}→Ξ^{-}e^{+}ν_{e})/B(Ξ_{c}^{0}→Ξ^{-}µ^{+}ν_{µ}) is 1.03±0.05±0.07, which is consistent with the expectation of lepton flavor universality. The first measured asymmetry parameter A_{CP}=(α_{Ξ^{-}π^{+}}+α_{Ξ[over ¯]^{+}π^{-}})/(α_{Ξ^{-}π^{+}}-α_{Ξ[over ¯]^{+}π^{-}})=0.024±0.052±0.014 is found to be consistent with zero. The first and the second uncertainties above are statistical and systematic, respectively, while the third ones arise due to the uncertainty of the Ξ_{c}^{0}→Ξ^{-}π^{+} branching fraction.

8.
Phys Rev Lett ; 124(12): 122001, 2020 Mar 27.
Article in English | MEDLINE | ID: mdl-32281835

ABSTRACT

We report the first observation of the radiative decay of the ϒ(1S) into a charmonium state. The significance of the observed signal of ϒ(1S)→γχ_{c1} is 6.3 standard deviations including systematics. The branching fraction is calculated to be B[ϒ(1S)→γχ_{c1}]=[4.7_{-1.8}^{+2.4}(stat)_{-0.5}^{+0.4}(sys)×10^{-5}]. We also searched for ϒ(1S) radiative decays into χ_{c0,2} and η_{c}(1S,2S), and set upper limits on their branching fractions. These results are obtained from a 24.9 fb^{-1} data sample collected with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider at a center-of-mass energy equal to the ϒ(2S) mass using ϒ(1S) tagging by the ϒ(2S)→ϒ(1S)π^{+}π^{-} transitions.

9.
Crop Prot ; 1352020 Sep.
Article in English | MEDLINE | ID: mdl-32742052

ABSTRACT

Trade and transport of goods is widely accepted as a primary pathway for the introduction and dispersal of invasive species. However, understanding commodity flows remains a challenge owing to its complex nature, unavailability of quality data, and lack of systematic modeling methods. A robust network-based approach is proposed to model seasonal flow of agricultural produce and examine its role in pest spread. It is applied to study the spread of Tuta absoluta, a devastating pest of tomato in Nepal. Further, the long-term establishment potential of the pest and its economic impact on the country are assessed. Our analysis indicates that regional trade plays an important role in the spread of T. absoluta. The economic impact of this invasion could range from USD 17-25 million. The proposed approach is generic and particularly suited for data-poor scenarios.

10.
Phys Rev Lett ; 122(8): 082001, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30932568

ABSTRACT

We present the first measurements of absolute branching fractions of Ξ_{c}^{0} decays into Ξ^{-}π^{+}, ΛK^{-}π^{+}, and pK^{-}K^{-}π^{+} final states. The measurements are made using a dataset comprising (772±11)×10^{6} BB[over ¯] pairs collected at the ϒ(4S) resonance with the Belle detector at the KEKB e^{+}e^{-} collider. We first measure the absolute branching fraction for B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0} using a missing-mass technique; the result is B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})=(9.51±2.10±0.88)×10^{-4}. We subsequently measure the product branching fractions B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→Ξ^{-}π^{+}), B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→ΛK^{-}π^{+}), and B(B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0})B(Ξ_{c}^{0}→pK^{-}K^{-}π^{+}) with improved precision. Dividing these product branching fractions by the result for B^{-}→Λ[over ¯]_{c}^{-}Ξ_{c}^{0} yields the following branching fractions: B(Ξ_{c}^{0}→Ξ^{-}π^{+})=(1.80±0.50±0.14)%, B(Ξ_{c}^{0}→ΛK^{-}π^{+})=(1.17±0.37±0.09)%, and B(Ξ_{c}^{0}→pK^{-}K^{-}π^{+})=(0.58±0.23±0.05)%. For the above branching fractions, the first uncertainties are statistical and the second are systematic. Our result for B(Ξ_{c}^{0}→Ξ^{-}π^{+}) can be combined with Ξ_{c}^{0} branching fractions measured relative to Ξ_{c}^{0}→Ξ^{-}π^{+} to yield other absolute Ξ_{c}^{0} branching fractions.

11.
Phys Rev Lett ; 122(1): 011801, 2019 Jan 11.
Article in English | MEDLINE | ID: mdl-31012694

ABSTRACT

We report on the first Belle search for a light CP-odd Higgs boson, A^{0}, that decays into low mass dark matter, χ, in final states with a single photon and missing energy. We search for events produced via the dipion transition ϒ(2S)→ϒ(1S)π^{+}π^{-}, followed by the on-shell process ϒ(1S)→γA^{0} with A^{0}→χχ, or by the off-shell process ϒ(1S)→γχχ. Utilizing a data sample of 157.3×10^{6} ϒ(2S) decays, we find no evidence for a signal. We set limits on the branching fractions of such processes in the mass ranges M_{A^{0}}<8.97 GeV/c^{2} and M_{χ}<4.44 GeV/c^{2}. We then use the limits on the off-shell process to set competitive limits on WIMP-nucleon scattering in the WIMP mass range below 5 GeV/c^{2}.

12.
Mol Psychiatry ; 23(8): 1745-1755, 2018 08.
Article in English | MEDLINE | ID: mdl-28485408

ABSTRACT

Development of an efficacious, non-addicting analgesic has been challenging. Discovery of novel mechanisms underlying addiction may present a solution. Here we target the neurokinin system, which is involved in both pain and addiction. Morphine exerts its rewarding actions, at least in part, by inhibiting GABAergic input onto substance P (SP) neurons in the ventral tegmental area (VTA), subsequently increasing SP release onto dopaminergic neurons. Genome editing of the neurokinin 1 receptor (NK1R) in the VTA renders morphine non-rewarding. Complementing our genetic approach, we demonstrate utility of a bivalent pharmacophore with dual activity as a µ/δ opioid agonist and NK1R antagonist in inhibiting nociception in an animal model of acute pain while lacking any positive reinforcement. These data indicate that dual targeting of the dopaminergic reward circuitry and pain pathways with a multifunctional opioid agonist-NK1R antagonist may be an efficacious strategy in developing future analgesics that lack abuse potential.


Subject(s)
Neurokinin-1 Receptor Antagonists/pharmacology , Opioid-Related Disorders/prevention & control , Receptors, Neurokinin-1/metabolism , Acute Pain/drug therapy , Acute Pain/metabolism , Analgesics/pharmacology , Animals , CRISPR-Cas Systems , Disease Models, Animal , Dopamine/metabolism , Escherichia coli , Gene Knockdown Techniques , Male , Mice, Inbred ICR , Morphine/pharmacology , Nociceptive Pain/drug therapy , Nociceptive Pain/metabolism , Opioid-Related Disorders/genetics , Opioid-Related Disorders/metabolism , Rats, Sprague-Dawley , Receptors, Neurokinin-1/genetics , Receptors, Opioid, delta/agonists , Receptors, Opioid, delta/metabolism , Receptors, Opioid, mu/agonists , Receptors, Opioid, mu/metabolism , Reward , Substance P/metabolism , Ventral Tegmental Area/drug effects , Ventral Tegmental Area/metabolism
13.
Phys Rev Lett ; 121(6): 062001, 2018 Aug 10.
Article in English | MEDLINE | ID: mdl-30141661

ABSTRACT

We report the first observation of the hadronic transition ϒ(4S)→η^{'}ϒ(1S), using 496 fb^{-1} data collected at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We reconstruct the η^{'} meson through its decays to ρ^{0}γ and to π^{+}π^{-}η, with η→γγ. We measure B(ϒ(4S)→η^{'}ϒ(1S))=[3.43±0.88(stat)±0.21(syst)]×10^{-5}, with a significance of 5.7σ.

14.
J Hum Nutr Diet ; 31(4): 513-522, 2018 08.
Article in English | MEDLINE | ID: mdl-29468754

ABSTRACT

BACKGROUND: Micronutrient deficiency is a global health burden, especially among developing countries. The present cross-sectional study aimed to determine the prevalence of vitamin B12 deficiency in healthy Indian school-going adolescents, based on area of residence, sex and body mass index (BMI). Furthermore, the relationship of serum B12 concentration with dietary vitamin B12 intake and anthropometric indices was assessed among adolescents from rural and urban India. METHODS: A total of 2403 school-going adolescents (11-17 years) from National Capital Region and rural areas of Haryana, India were selected. Serum B12 concentrations were estimated using an electrochemiluminescence immunoassay. Dietary assessments were conducted on 65% of total participants (n = 1556) by two 24-h diet recalls. RESULTS: The prevalence of vitamin B12 deficiency in the total study population was 32.4% (rural: 43.9% versus urban: 30.1%, P < 0.001; male: 34.4% versus female: 31.0%, P < 0.05; normal weight: 28.1%, versus overweight: 39.8%, versus obese: 51.2%, P < 0.001). More than half (51.2%) of obese adolescents were vitamin B12 deficient. On multiple linear regression analysis, serum B12 in rural adolescents was associated with age (ß = -0.12, P < 0.05). Among urban adolescents, serum B12 was associated with BMI (ß = -0.08, P < 0.05) and adjusted dietary vitamin B12 intake (ß = 0.14, P < 0.001). Serum vitamin B12 levels were found to be lower in rural females (ß = -0.12, P = 0.030) and urban males (ß: 0.11, P < 0.001) compared to their respective contemporaries. CONCLUSIONS: Vitamin B12 deficiency was higher among rural school-going adolescents. Boys had a higher B12 deficiency than girls. Inverse associations of serum B12 with adiposity indices were observed. Serum B12 levels were positively associated with dietary vitamin B12 intake.


Subject(s)
Adolescent Health/statistics & numerical data , Rural Population , Urban Population , Vitamin B 12 Deficiency/epidemiology , Adolescent , Age Factors , Body Mass Index , Child , Female , Humans , India/epidemiology , Male , Obesity/epidemiology , Overweight/epidemiology , Sex Factors , Students , Vitamin B 12/blood
15.
Kathmandu Univ Med J (KUMJ) ; 15(59): 235-239, 2017.
Article in English | MEDLINE | ID: mdl-30353899

ABSTRACT

Background Flexible airway endoscopy is a highly valuable procedure for evaluating pediatric airway and pulmonary disorders. However, its use in our setup is limited. Objective The main objective of this study is to analyze indications for flexible airway endoscopy in our population, explore its diagnostic yield and highlight potential complications. Method Seventy flexible airway endoscopies performed in children at Nepal Medical College and Teaching Hospital from June, 2013 to May, 2015 were analyzed. Result Fifty six (80%) of airway endoscopy had a meaningful outcome. Diagnostic yield for individual indications ranged from 50 to 87.5%. Recurrent/persistent pneumonia was the most rewarding indication. Complications were minimal and easily reversible. Conclusion The overall diagnostic yield of flexible airway endoscopy in our study population was 80%. The procedure was safe with minimal complication. Hence, earlier intervention and utilization of bronchoscopy should be encouraged after a careful clinical consideration of patients who could potentially benefit from this procedure.


Subject(s)
Endoscopy/methods , Lung Diseases/diagnosis , Adolescent , Bronchoscopy/methods , Bronchoscopy/statistics & numerical data , Child , Child, Preschool , Early Diagnosis , Endoscopy/statistics & numerical data , Female , Humans , Infant , Male , Nepal , Retrospective Studies
16.
Acta Mater ; 97: 245-256, 2015 Sep 15.
Article in English | MEDLINE | ID: mdl-27099566

ABSTRACT

Currently, there is significant interest in magnetocaloric materials for solid state refrigeration. In this work, polycrystalline Heusler alloys belonging to the Ni2+xMn1-xGa family, with x between 0.08 and 0.24, were evaluated for the purpose of finding composition(s) with an enhanced magnetocaloric effect (MCE) close to room temperature. Differential scanning calorimetry (DSC) was successfully used to screen alloy composition for simultaneous magnetic and structural phase transformations; this coupling needed for a giant MCE. The alloy with x = 0.16 showed an excellent match of transformation temperatures and exhibited the highest magnetic entropy change, ΔSM, in the as-annealed state. Furthermore, the MCE increased by up to 84 % with a 2 Tesla (T) field change when the samples were thermally cycled through the martensite to austenite transformation temperature while held under a constant mechanical load. The highest ΔSM measured for our x = 0.16 alloy for a 2 T magnetic field change was -18 J/kg-K. Texture measurements suggest that preferential orientation of martensite variants contributed to the enhanced MCE in the stress-assisted thermally cycled state.

17.
Nat Commun ; 15(1): 9135, 2024 Oct 23.
Article in English | MEDLINE | ID: mdl-39443472

ABSTRACT

Energy absorption by matter is fundamental to natural and man-made processes. However, despite this ubiquity, developing materials capable of withstanding severe energy fluxes without degradation is a significant challenge in materials science and engineering. Despite recent advances in creating alloys resistant to energy fluxes, mitigating the damage caused by the absorption and transfer of mechanical energy remains a critical obstacle in both fundamental science and technological applications. This challenge is especially prominent when the mechanical energy is transferred to the material by shock loading. This study demonstrates a phenomenon in which microstructurally stabilized nanocrystalline Cu-Ta alloys can undergo reversal or nearly complete recovery of the dislocation structure after multiple shock-loading impacts, unlike any other known metallic material. The microstructure of these alloys can withstand repeated shock-wave interactions at pressures up to 12 GPa without any significant microstructural damage or deterioration, demonstrating an extraordinary capacity to be virtually immune to the detrimental effects of shock loading.

18.
Insect Mol Biol ; 22(3): 258-72, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23432026

ABSTRACT

Helicoverpa armigera (Lepidoptera: Noctuidae) and other polyphagous agricultural pests are extending their plant host range and emerging as serious agents in restraining crop productivity. Dynamic regulation, coupled with a diversity of digestive and detoxifying enzymes, play a crucial role in the adaptation of polyphagous insects. To investigate the functional intricacy of serine proteases in the development and polyphagy of H. armigera, we profiled the expression of eight trypsin-like and four chymotrypsin-like phylogenetically diverse mRNAs from different life stages of H. armigera reared on nutritionally distinct host plants. These analyses revealed diet- and stage-specific protease expression patterns. The trypsins expressed showed structural variations, which might result in differential substrate specificity and interaction with inhibitors. Protease profiles in the presence of inhibitors and their mass spectrometric analyses revealed insight into their differential activity. These findings emphasize the differential expression of serine proteases and their consequences for digestive physiology in promoting polyphagy in H. armigera.


Subject(s)
Chymotrypsin/metabolism , Insect Proteins/metabolism , Moths/enzymology , Trypsin/metabolism , Animals , Chromatography, Liquid , Chymotrypsin/genetics , Diet , Gastrointestinal Tract/enzymology , Gene Expression Regulation, Developmental , Insect Proteins/genetics , Larva/enzymology , Larva/growth & development , Mass Spectrometry , Moths/genetics , Moths/growth & development , Pupa/enzymology , Pupa/growth & development , Real-Time Polymerase Chain Reaction , Sequence Analysis, Protein , Trypsin/genetics
19.
J Insect Sci ; 12: 42, 2012.
Article in English | MEDLINE | ID: mdl-22954360

ABSTRACT

Developmental patterns and survival of the cotton bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), a polyphagous insect pest, have been studied with reference to the effect of diet on major gut digestive enzymes (amylases, proteases, and lipases). Significant correlations between nutritional quality of the diet and larval and pupal mass were observed when H. armigera larvae were fed on various host plants viz. legumes (chickpea and pigeonpea), vegetables (tomato and okra), flowers (rose and marigold), and cereals (sorghum and maize). Larvae fed on diets rich in proteins and/or carbohydrates (pigeonpea, chickpea, maize, and sorghum) showed higher larval mass and developed more rapidly than larvae fed on diets with low protein and carbohydrate content (rose, marigold, okra, and tomato). Low calorific value diets like rose and marigold resulted in higher mortality (25-35%) of H. armigera. Even with highly varying development efficiency and larval/pupal survival rates, H. armigera populations feeding on different diets completed their life cycles. Digestive enzymes of H. armigera displayed variable expression levels and were found to be regulated on the basis of macromolecular composition of the diet. Post-ingestive adaptations operating at the gut level, in the form of controlled release of digestive enzymes, might be a key factor contributing to the physiological plasticity in H. armigera.


Subject(s)
Insect Proteins/metabolism , Moths/growth & development , Moths/metabolism , Plants/chemistry , Amylases/metabolism , Animals , Carboxylic Ester Hydrolases/metabolism , Dietary Carbohydrates/metabolism , Dietary Proteins/metabolism , Larva/enzymology , Larva/growth & development , Larva/metabolism , Lipid Metabolism , Moths/enzymology , Nutritive Value , Peptide Hydrolases/metabolism , Pupa/enzymology , Pupa/growth & development , Pupa/metabolism
20.
Water Sci Technol ; 66(8): 1699-707, 2012.
Article in English | MEDLINE | ID: mdl-22907454

ABSTRACT

In this work, the biosorption of As(V) from aqueous solutions by living cells of Bacillus cereus has been reported. The batch biosorption experiments were conducted with respect to biosorbent dosage 0.5 to 15 g/L, pH 2 to 9, contact time 5 to 90 min, initial concentration 1 to 10 mg/L and temperature 10 to 40 °C. The maximum biosorption capacity of B. cereus for As(V) was found to be 30.04 at pH 7.0, at optimum conditions of contact time of 30 min, biomass dosage of 6 g/L, and temperature of 30 ± 2 °C. Biosorption data were fitted to linearly transformed Langmuir isotherms with R(2) (correlation coefficient) >0.99. Bacillus cereus cell surface was characterized using AFM and FTIR. The metal ions were desorbed from B. cereus using both 1 M HCl and 1 M HNO(3). The pseudo-second-order model was successfully applied to predict the rate constant of biosorption.


Subject(s)
Arsenic/metabolism , Bacillus cereus/metabolism , Biodegradation, Environmental , Water Pollutants, Chemical/metabolism , Solutions
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