222 research outputs found
Distribution of \u3cem\u3eCotesia rubecula\u3c/em\u3e (Hymenoptera: Braconidae) and Its Displacement of \u3cem\u3eCotesia glomerata\u3c/em\u3e in Eastern North America
A survey was conducted from May to Oct of 2011 of the parasitoid community of the imported cabbageworm, Pieris rapae (Lepidoptera: Pieridae), in cole crops in part of the eastern United States and southeastern Canada. The findings of our survey indicate that Cotesia rubecula (Hymenoptera: Braconidae) now occurs as far west as North Dakota and has become the dominant parasitoid of P. rapae in the northeastern and north central United States and adjacent parts of southeastern Canada, where it has displaced the previously common parasitoid Cotesia glomerata (Hymenoptera: Braconidae). Cotesia glomerata remains the dominant parasitoid in the mid-Atlantic states, from Virginia to North Carolina and westward to southern Illinois, below latitude N 38° 48′. This pattern suggests that the released populations of C. rubecula presently have a lower latitudinal limit south of which they are not adapted
STIX X-ray microflare observations during the Solar Orbiter commissioning phase
Context. The Spectrometer/Telescope for Imaging X-rays (STIX) is the hard X-ray instrument onboard Solar Orbiter designed to observe solar flares over a broad range of flare sizes. Aims. We report the first STIX observations of solar microflares recorded during the instrument commissioning phase in order to investigate the STIX performance at its detection limit. Methods. STIX uses hard X-ray imaging spectroscopy in the range between 4-150 keV to diagnose the hottest flare plasma and related nonthermal electrons. This first result paper focuses on the temporal and spectral evolution of STIX microflares occuring in the Active Region (AR) AR12765 in June 2020, and compares the STIX measurements with Earth-orbiting observatories such as the X-ray Sensor of the Geostationary Operational Environmental Satellite (GOES/XRS), the Atmospheric Imaging Assembly of the Solar Dynamics Observatory, and the X-ray Telescope of the Hinode mission. Results. For the observed microflares of the GOES A and B class, the STIX peak time at lowest energies is located in the impulsive phase of the flares, well before the GOES peak time. Such a behavior can either be explained by the higher sensitivity of STIX to higher temperatures compared to GOES, or due to the existence of a nonthermal component reaching down to low energies. The interpretation is inconclusive due to limited counting statistics for all but the largest flare in our sample. For this largest flare, the low-energy peak time is clearly due to thermal emission, and the nonthermal component seen at higher energies occurs even earlier. This suggests that the classic thermal explanation might also be favored for the majority of the smaller flares. In combination with EUV and soft X-ray observations, STIX corroborates earlier findings that an isothermal assumption is of limited validity. Future diagnostic efforts should focus on multi-wavelength studies to derive differential emission measure distributions over a wide range of temperatures to accurately describe the energetics of solar flares. Conclusions. Commissioning observations confirm that STIX is working as designed. As a rule of thumb, STIX detects flares as small as the GOES A class. For flares above the GOES B class, detailed spectral and imaging analyses can be performed
Withania somnifera Root Extract Enhances Chemotherapy through ‘Priming’
Withania somnifera extracts are known for their anti-cancerous, anti-inflammatory and antioxidative properties. One of their mechanisms of actions is to modulate mitochondrial function through increasing oxidative stress. Recently ‘priming’ has been suggested as a potential mechanism for enhancing cancer cell death. In this study we demonstrate that ‘priming’, in HT-29 colon cells, with W. somnifera root extract increased the potency of the chemotherapeutic agent cisplatin. We have also showed the W. somnifera root extract enhanced mitochondrial dysfunction and that the underlying mechanism of ‘priming’ was selectively through increased ROS. Moreover, we showed that this effect was not seen in non-cancerous cells
CART Peptide Is a Potential Endogenous Antioxidant and Preferentially Localized in Mitochondria
The multifunctional neuropeptide Cocaine and Amphetamine Regulated Transcript (CART) is secreted from hypothalamus, pituitary, adrenal gland and pancreas. It also can be found in circulatory system. This feature suggests a general role for CART in different cells. In the present study, we demonstrate that CART protects mitochondrial DNA (mtDNA), cellular proteins and lipids against the oxidative action of hydrogen peroxide, a widely used oxidant. Using cis-parinaric acid as a sensitive reporting probe for peroxidation in membranes, and a lipid-soluble azo initiator of peroxyl radicals, 2,2′-Azobis(2,4-dimethylvaleronitrile) we found that CART is an antioxidant. Furthermore, we found that CART localized to mitochondria in cultured cells and mouse brain neuronal cells. More importantly, pretreatment with CART by systemic injection protects against a mouse oxidative stress model, which mimics the main features of Parkinson's disease. Given the unique molecular structure and biological features of CART, we conclude that CART is an antioxidant peptide (or antioxidant hormone). We further propose that it may have strong therapeutic properties for human diseases in which oxidative stress is strongly involved such as Parkinson's disease
Extended Sentinel Monitoring of Helicoverpa zea Resistance to Cry and Vip3Aa Toxins in Bt Sweet Corn: Assessing Changes in Phenotypic and Allele Frequencies of Resistance
Transgenic corn and cotton that produce Cry and Vip3Aa toxins derived from Bacillus thuringiensis (Bt) are widely planted in the United States to control lepidopteran pests. The sustainability of these Bt crops is threatened because the corn earworm/bollworm, Helicoverpa zea (Boddie), is evolving a resistance to these toxins. Using Bt sweet corn as a sentinel plant to monitor the evolution of resistance, collaborators established 146 trials in twenty-five states and five Canadian provinces during 2020–2022. The study evaluated overall changes in the phenotypic frequency of resistance (the ratio of larval densities in Bt ears relative to densities in non-Bt ears) in H. zea populations and the range of resistance allele frequencies for Cry1Ab and Vip3Aa. The results revealed a widespread resistance to Cry1Ab, Cry2Ab2, and Cry1A.105 Cry toxins, with higher numbers of larvae surviving in Bt ears than in non-Bt ears at many trial locations. Depending on assumptions about the inheritance of resistance, allele frequencies for Cry1Ab ranged from 0.465 (dominant resistance) to 0.995 (recessive resistance). Although Vip3Aa provided high control efficacy against H. zea, the results show a notable increase in ear damage and a number of surviving older larvae, particularly at southern locations. Assuming recessive resistance, the estimated resistance allele frequencies for Vip3Aa ranged from 0.115 in the Gulf states to 0.032 at more northern locations. These findings indicate that better resistance management practices are urgently needed to sustain efficacy the of corn and cotton that produce Vip3Aa
High-Energy-Resolution Inelastic Electron and Proton Scattering and the Multiphonon Nature of Mixed-Symmetry 2 States in 94 Mo
High-energy-resolution inelastic electron scattering (at the S-DALINAC) and proton scattering (at iThemba LABS) experiments permit a thorough test of the nature of proposed one-and two-phonon symmetric and mixed-symmetric 2 states of the nucleus 94 Mo. The combined analysis reveals the onephonon content of the mixed-symmetry state and its isovector character suggested by microscopic nuclear model calculations. The purity of two-phonon 2 states is extracted. DOI: 10.1103/PhysRevLett.99.092503 PACS numbers: 21.10.Re, 25.30.Dh, 25.40.Ep, 27.60.+j Collective valence-shell excitations are a generic feature of strongly-coupled mesoscopic quantum systems. A prime example of a two-component system is the atomic nucleus formed by protons and neutrons. The microscopic structure of collective nuclear excitations with respect to their proton-neutron content is a central issue of nuclear structure physics with general implications for the physics of composite strongly-coupled quantum systems. Low-energy nuclear valence-shell excitations usually possess the lowest possible isospin quantum number T < jN ÿ Zj=2. Nevertheless, the symmetry character of their proton-neutron coupling can vary. This fact is evident in the framework Recently, one-and two-phonon MSSs were investigated in vibrational nuclei with proton and neutron numbers near closed shells, e.g., in the nuclide 94 Mo [5]. Comprehensive spectroscopic information on low-spin states has been achieved up to an excitation energy of about 4 MeV It is the purpose of this Letter to report a combined study of electron and proton scattering differential cross sections for J 2 one-and two-phonon FSSs and MSSs in 94 Mo. The selectivity of both reactions to one-phonon components in the excited state wave functions allows to extract for the first time the small one-phonon contributions to the two-phonon candidates. The proton-neutron symmetry character can be derived since electron scattering couples to the proton distributions, while proton scattering is dominated by the isoscalar central part of the effective proton-nucleus interaction. We thereby introduce a new approach establishing a multiphonon character of nuclear MSSs based on scattering data complementary to -ray spectroscopy. The (e; e 0 ) experiments were carried out at the highenergy-resolution magnetic spectromete
Internet of Things for Sustainable Mining
The sustainable mining Internet of Things deals with the applications of IoT technology to the coupled needs of sustainable recovery of metals and a healthy environment for a thriving planet. In this chapter, the IoT architecture and technology is presented to support development of a digital mining platform emphasizing the exploration of rock–fluid–environment interactions to develop extraction methods with maximum economic benefit, while maintaining and preserving both water quantity and quality, soil, and, ultimately, human health. New perspectives are provided for IoT applications in developing new mineral resources, improved management of tailings, monitoring and mitigating contamination from mining. Moreover, tools to assess the environmental and social impacts of mining including the demands on dwindling freshwater resources. The cutting-edge technologies that could be leveraged to develop the state-of-the-art sustainable mining IoT paradigm are also discussed
Flavonoids in prevention of diseases with respect to modulation of Ca-pump function
Flavonoids, natural phenolic compounds, are known as agents with strong antioxidant properties. In many diseases associated with oxidative/nitrosative stress and aging they provide multiple biological health benefits. Ca2+-ATPases belong to the main calcium regulating proteins involved in the balance of calcium homeostasis, which is impaired in oxidative/nitrosative stress and related diseases or aging. The mechanisms of Ca2+-ATPases dysfunction are discussed, focusing on cystein oxidation and tyrosine nitration. Flavonoids act not only as antioxidants but are also able to bind directly to Ca2+-ATPases, thus changing their conformation, which results in modulation of enzyme activity
Glucocortiocoid Treatment of MCMV Infected Newborn Mice Attenuates CNS Inflammation and Limits Deficits in Cerebellar Development
Infection of the developing fetus with human cytomegalovirus (HCMV) is a major cause of central nervous system disease in infants and children; however, mechanism(s) of disease associated with this intrauterine infection remain poorly understood. Utilizing a mouse model of HCMV infection of the developing CNS, we have shown that peripheral inoculation of newborn mice with murine CMV (MCMV) results in CNS infection and developmental abnormalities that recapitulate key features of the human infection. In this model, animals exhibit decreased granule neuron precursor cell (GNPC) proliferation and altered morphogenesis of the cerebellar cortex. Deficits in cerebellar cortical development are symmetric and global even though infection of the CNS results in a non-necrotizing encephalitis characterized by widely scattered foci of virus-infected cells with mononuclear cell infiltrates. These findings suggested that inflammation induced by MCMV infection could underlie deficits in CNS development. We investigated the contribution of host inflammatory responses to abnormal cerebellar development by modulating inflammatory responses in infected mice with glucocorticoids. Treatment of infected animals with glucocorticoids decreased activation of CNS mononuclear cells and expression of inflammatory cytokines (TNF-α, IFN-β and IFNγ) in the CNS while minimally impacting CNS virus replication. Glucocorticoid treatment also limited morphogenic abnormalities and normalized the expression of developmentally regulated genes within the cerebellum. Importantly, GNPC proliferation deficits were normalized in MCMV infected mice following glucocorticoid treatment. Our findings argue that host inflammatory responses to MCMV infection contribute to deficits in CNS development in MCMV infected mice and suggest that similar mechanisms of disease could be responsible for the abnormal CNS development in human infants infected in-utero with HCMV
Individual, social, and environmental factors affecting salivary and fecal cortisol levels in captive pied tamarins (Saguinus bicolor)
This is the peer reviewed version of the following article: Price, E., Coleman, R., Ahsmann, J., Glendewar, G., Hunt, J., Smith, T. & Wormell, D. (2019). Individual, social, and environmental factors affecting salivary and fecal cortisol levels in captive pied tamarins (Saguinus bicolor). American Journal of Primatology, 81(8), which has been published in final form at https://doi.org/10.1002/ajp.23033. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingPied tamarins (Saguinus bicolor) are endangered New World primates, and in captivity
appear to be very susceptible to stress. We measured cortisol in 214 saliva samples
from 36 tamarins and in 227 fecal samples from 27 tamarins, and investigated
the effects of age, sex, pregnancy, rearing history, social status, weight, group
composition, and enclosure type using generalized linear mixed models. There was no
effect of age on either fecal or salivary cortisol levels. Female pied tamarins in late
pregnancy had higher fecal cortisol levels than those in early pregnancy, or
nonpregnant females, but there was no effect of pregnancy on salivary cortisol.
Females had higher salivary cortisol levels than males, but there was no effect of
rearing history. However, for fecal cortisol, there was an interaction between sex and
rearing history. Hand‐reared tamarins overall had higher fecal cortisol levels, but
while male parent‐reared tamarins had higher levels than females who were parent‐
reared, the reverse was true for hand‐reared individuals. There was a trend towards
lower fecal cortisol levels in subordinate individuals, but no effect of status on
salivary cortisol. Fecal but not salivary cortisol levels declined with increasing weight.
We found little effect of group composition on cortisol levels in either saliva or feces,
suggesting that as long as tamarins are housed socially, the nature of the group is of
less importance. However, animals in off‐show enclosures had higher salivary and
fecal cortisol levels than individuals housed on‐show. We suggest that large on‐show
enclosures with permanent access to off‐exhibit areas may compensate for the
effects of visitor disturbance, and a larger number of tamarins of the same species
housed close together may explain the higher cortisol levels found in tamarins living
in off‐show accommodation, but further research is needed
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