802 research outputs found
Influence of Temperature and Concentration on the Self-Assembly of Nonionic CiEjSurfactants: A Light Scattering Study
Nonionic poly(ethylene oxide) alkyl ether (CiE) surfactants self-assemble into aggregates of various sizes and shapes above their critical micelle concentration (CMC). Knowledge on solution attributes such as CMC as well as aggregate characteristics is crucial to choose the appropriate surfactant for a given application, e.g., as a micellar solvent system. In this work, we used static and dynamic light scattering to measure the CMC, aggregation number (N), and hydrodynamic radius (R) of four different CE surfactants (CE, CE, CE, and CE). We examined the influence of temperature, concentration, and molecular structure on the self-assembly in the vicinity of the CMC. A minimum in the CMC vs temperature curve was identified for all surfactants investigated. Further, extending the hydrophilic and hydrophobic chain lengths leads to an increase and decrease of the CMC, respectively. The size of the aggregates strongly depends on temperature. N and R increase with increasing temperature for all surfactants investigated. Additionally, N and R both increase with increasing surfactant concentration. The data obtained in this work further improve the understanding of the influence of temperature and molecular structure on the self-assembly of CiE surfactants and will further foster their use in micellar solvent systems
Effect of DDGS manure on soil and plant: preliminary results of the greenhouse study
Non-Peer ReviewedThe use of dried distillers’ grains with solubles (DDGS) in feedlot cattle diets is increasing as the
bio-ethanol industry expands. Manure derived from dried distiller’s grain with solubles (DDGS)
fed cattle seem to have higher amounts of N and P than manure from regular grain fed cattle.
This study investigates how DDGS manure affects soil fertility and nutrient uptake by barley
grown in a controlled greenhouse environment. Both DDGS and regular manure were applied at
30, 60, 120 and 180 Mg ha-1 yr-1 to a sand soil. The results of the first 3 harvest cycles indicate
that both types of manure resulted in similar increase in plant total P content. However, soil TP
and available P concentrations in DDGS manure treatments were higher. Soil available in DDGS
treatments was twice as much of that in regular manure. Increase in soil TN and available N
contents was similar with both types of manure. Plant TN content did not seem to be influenced
by manure application. This study indicates that the main concern with the use of DDGS manure
is its high P solubility. However, no significant increase in soil available P was observed at a
manure rate of 30 Mg ha-1 yr-1
Determination of proper gamma radiation dose for creating variation in Indian garlic varieties
Garlic (Allium sativum L.) an important neutraceutical crop. It is used as traditional medicine to aid digestion, respiration, parasitic infestation and to treat leprosy and various other diseases. But biologically garlic is sterile in nature hence for creating variation; traditional breeding methods are not applicable. Further clonal propagation method leads garlic more prone for various seed and soil borne diseases including virus infection. And natural genetic variation in morphological as well as biochemical traits is limited in garlic. Considering this is in view, among various methods of creating variation, treating bulbs with radiation is simple and easy technique. Main activity of mutation breeding using gamma radiation is to determine optimum dose (LD-50). Hence in present experiment, two garlic varieties were subjected to gamma radiation treatments (0, 1, 5, 10, 25, 50, 75 and 100 gray). Aim of this experiment is to identify LD-50 dose and then generate variation in garlic like increase in bulb size, bulb shape, high neutraceutical compounds like allicin etc. In results, both treated varieties recorded 50 percent germination at dose 10 grays as LD-50. Further on basis of survival of plantlets and final matured plants count, optimum gamma radiation dose of 5 gray for Bhima Omkar and in between 5 to 10 gray for Bhima Purple is identified as LD-50 respectively. In case of Bhima Purple, there is further need to screen the population for exact dose value of LD-50. All other morphological traits in both varieties recorded decreasing trend with increase in radiation doses. However no significant alterations observed visually in any treatment. This optimized radiation dose will be helpful for subjecting other genotypes for getting mutants and generating diversity in garlic which may have high neutracutical compounds and would suitable for processing and export
Inductive-Inductive Definitions
This article presents a new extension of inductive definitions, namely inductive-inductive definitions
VLBI Probes of Jet Physics in Neutrino-Candidate Blazars
In recent years, evidence has accumulated that some high-energy cosmic
neutrinos can be associated with blazars. The strongest evidence for an
individual association was found in the case of the blazar TXS 0506+056 in
2017. In July 2019, another track-like neutrino event (IC190730A) was found
spatially coincident with the well-known bright flat-spectrum radio quasar PKS
1502+106. PKS 1502+106 was not found to be in a particularly elevated gamma-ray
state, but exhibited a remarkably bright radio outburst at the time of the
neutrino detection, similar to TXS 0506+056. We have performed a
multi-frequency VLBI study from 15 GHz up to 86 GHz on TXS 0506+056, PKS
1502+106 and one additional neutrino-candidate blazar (PKS 0215+015) to study
the radio structure of neutrino candidate blazars in response to their neutrino
association. We have obtained target of opportunity observations with the VLBA
for all three sources within 1 month from their associated neutrino
events and are performing multi-epoch studies of the jet kinematics at 15 GHz
as part of the MOJAVE program. Here, we present first results on TXS 0506+056
at 86 GHz and one additional 43 GHz image obtained 27 days after IC170922A,
closer in time to the neutrino event than previously published images. We also
give an overview about our recent work on PKS 1502+106 and PKS 0215+015.Comment: 8 pages, 1 figure, 1 table, Proceedings of 38th International Cosmic
Ray Conference (ICRC2023
Occupational exposure to N-nitrosamines and pesticides and risk of pancreatic cancer
Objectives Animal evidence shows that N-nitrosamines and similar xenobiotic compounds are pancreatic carcinogens. We aimed to determine whether occupational exposure to N-nitrosamines or to pesticides increases risk of pancreatic cancer development. Methods Participants (504 cases, 643 controls) in a population-based case-control study (The Queensland Pancreatic Cancer Study) provided data on demographic, medical and lifestyle factors and lifetime job histories. Specific questions were asked regarding work in rubber and leather industries, metalworking jobs and occupational or direct use of pesticides on animals or crops. An occupational hygienist reviewed this information (blind to case status) to assess likelihood of exposure to N-nitrosamines and pesticides, and estimated level and frequency of such exposures. Results No associations were found for risk of pancreatic cancer and occupational exposure to N-nitrosamines (OR=0.85, 95% CI 0.51 to 1.42) and no associations were seen with level or frequency of exposure. No associations were observed for ever exposure to pesticides in general (OR=0.90, 95% CI 0.61 to 1.33) or to any of the pesticide subgroups. Stratification by history of cigarette smoking did not change these results. Conclusions This comprehensive analysis of a large case-control study does not support an association between occupational exposure to N-nitrosamines or pesticide use and risk of pancreatic cancer
From binary to singular: the AGN PSO J334.2028+1.4075 under the high-resolution scope
PSO J334.2028+1.4075 (PSO J334) is a luminous quasar located at redshift
z=2.06. The source gained attention when periodic flux density variations were
discovered in its optical light curve. These variations were initially
interpreted as the variability due to the orbital motion of a supermassive
black hole binary (SMBHB) residing in a single circumbinary accretion disk.
However, subsequent multiwavelength observations provided evidence against the
binary hypothesis as no optical periodicity was found on extended time
baselines. On the other hand, detailed radio analysis with the Karl G. Jansky
Very Large Array (VLA) and the Very Long Baseline Array (VLBA) revealed a
lobe-dominated quasar at kpc scales, and possibly a precessing jet, which could
retain PSO J334 as a binary SMBH candidate. We aim to study both the large- and
small-scale radio structures in PSO J334 to provide additional evidence for or
against the binary scenario. We observed the source at 1.7 GHz with the
European Very Long Baseline Interferometry Network (EVN), and at 1.5 and 6.2
GHz with the VLA, at frequencies that complement the previous radio
interferometric study. Our images reveal a single component at parsec scales
slightly resolved in the southeast-northwest direction and a lobe-dominated
quasar at kiloparsec scales with a complex structure. The source morphology and
polarization in our VLA maps suggest that the jet is interacting with dense
clumps of the ambient medium. While we also observe a misalignment between the
inner jet and the outer lobes, we suggest that this is due to the restarted
nature of the radio jet activity and the possible presence of a warped
accretion disk rather than due to the perturbing effects of a companion SMBH.
Our analysis suggests that PSO J334 is most likely a jetted AGN with a single
SMBH, and there is no clear evidence of a binary SMBH system in its central
engine
Targeting the interaction of GABA receptors with CaMKII with an interfering peptide restores receptor expression after cerebral ischemia and inhibits progressive neuronal death in mouse brain cells and slices
Cerebral ischemia is the leading cause for long-term disability and mortality in adults due to massive neuronal death. Currently, there is no pharmacological treatment available to limit progressive neuronal death after stroke. A major mechanism causing ischemia-induced neuronal death is the excessive release of glutamate and the associated overexcitation of neurons (excitotoxicity). Normally, GABA receptors control neuronal excitability in the brain via prolonged inhibition. However, excitotoxic conditions rapidly downregulate GABA receptors via a CaMKII-mediated mechanism and thereby diminish adequate inhibition that could counteract neuronal overexcitation and neuronal death. To prevent the deleterious downregulation of GABA receptors, we developed a cell-penetrating synthetic peptide (R1-Pep) that inhibits the interaction of GABA receptors with CaMKII. Administration of this peptide to cultured cortical neurons exposed to excitotoxic conditions restored cell surface expression and function of GABA receptors. R1-Pep did not affect CaMKII expression or activity but prevented its T286 autophosphorylation that renders it autonomously and persistently active. Moreover, R1-Pep counteracted the aberrant downregulation of G protein-coupled inwardly rectifying K channels and the upregulation of N-type voltage-gated Ca channels, the main effectors of GABA receptors. The restoration of GABA receptors activated the Akt survival pathway and inhibited excitotoxic neuronal death with a wide time window in cultured neurons. Restoration of GABA receptors and neuroprotective activity of R1-Pep was verified by using brain slices prepared from mice after middle cerebral artery occlusion (MCAO). Treatment with R1-Pep restored normal GABA receptor expression and GABA receptor-mediated K channel currents. This reduced MCAO-induced neuronal excitability and inhibited neuronal death. These results support the hypothesis that restoration of GABA receptor expression under excitatory conditions provides neuroprotection and might be the basis for the development of a selective intervention to inhibit progressive neuronal death after ischemic stroke
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