In situ Impact of the Antagonistic Fungal Strain, Trichoderma gamsii T30 on the Plant Pathogenic Fungus, Rhizoctonia solani in Soil

Rhizoctonia solani is a soil-borne fungus causing a wide range of plants diseases. Trichoderma gamsii strain T30 has previously been reported as antagonistic against R. solani. Although there are a few studies about the influence of Trichoderma strains on the R. solani densityin a pathosystem in the presence of plant hosts, this report for the first time comprehensively describes in situ effects of a T. gamsii strain on the population density of R. solani in the soil microcosmic conditions. The population dynamics of R. solani were followed in the autoclaved and non-autoclaved soils in artificially prepared microcosms up to day 25 after co-inoculation with T. gamsii in the variable ratios (R1/T1; R1/T0.1; R1/T0.01 of R. solani/T. gamsii). The population density of R. solani was evaluated by qPCR. In the autoclaved soil, target DNA copies of R. solani increased in the control samples from 1 × 105 to 6.5 × 106. At R1/T0.01, the number of target DNA copies were not significantly changed until day 11; however, it decreased by around five times at day 25. At R1/T0.1 and R1/T1, the number of DNA copies was reduced to 2.1 × 106 and 7.6 × 105 at day 11, respectively and the reduction was as much as 17 times at day 25. In the non-autoclaved soil, the number of the fungal cells decreased at day 25 whether inoculated or not with Trichoderma indicating a general suppression by the soil microbiome. In brief, T. gamsii significantly inhibited the growth of R. solani in the soil in situ and there was a general suppressive effect of the natural microbiome.

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Unique heliophysics science opportunities along the Interstellar Probe journey up to 1000 AU from the Sun

10.5194/egusphere-egu21-10504 ◽

2021 ◽

Author(s):

Elena Provornikova ◽

Pontus C. Brandt ◽

Ralph L. McNutt, Jr. ◽

Robert DeMajistre ◽

Edmond C. Roelof ◽

...

Keyword(s):

Space Mission ◽

In Situ Measurements ◽

Unique Determination ◽

The Sun ◽

Global Shape ◽

Wide Range ◽

First Time ◽

Interstellar Probe ◽

Probe Mission

The Interstellar Probe is a space mission to discover physical interactions shaping globally the boundary of our Sun`s heliosphere and its dynamics and for the first time directly sample the properties of the local interstellar medium (LISM). Interstellar Probe will go through the boundary of the heliosphere to the LISM enabling for the first time to explore the boundary with a dedicated instrumentation, to take the image of the global heliosphere by looking back and explore in-situ the unknown LISM. The pragmatic concept study of such mission with a lifetime 50 years that can be implemented by 2030 was funded by NASA and has been led by the Johns Hopkins University Applied Physics Laboratory (APL). The study brought together a diverse community of more than 400 scientists and engineers spanning a wide range of science disciplines across the world.Compelling science questions for the Interstellar Probe mission have been with us for many decades. Recent discoveries from a number of space missions exploring the heliosphere raised new questions strengthening the science case. The very shape of the heliosphere, a manifestation of complex global interactions between the solar wind and the LISM, remains the biggest mystery. Interpretations of imaging the heliosphere in energetic neutral atoms (ENAs) in different energy ranges on IBEX and Cassini/INCA from inside show contradictory pictures. Global physics-based models also do not agree on the global shape. Interstellar Probe on outbound trajectory will image the heliosphere from outside for the first time and will provide a unique determination of the global shape.The LISM is a completely new area for exploration and discovery. We have a crude understanding of the LISM inferred from in-situ measurements inside the heliosphere of interstellar helium, pick-up-ions, ENAs, remote observations of solar backscattered Lyman-alpha emission and absorption line spectroscopy in the lines of sight of stars. We have no in-situ measurements of most LISM properties, e.g. ionization, plasma and neutral gas, magnetic field, composition, dust, and scales of possible inhomogeneities. Voyagers with limited capabilities have explored 30 AU beyond the heliosphere which appeared to be a region of significant heliospheric influence. The LISM properties are among the key unknowns to understand the Sun`s galactic neighborhood and how it shapes our heliosphere. Interstellar Probe will be the first NASA mission to discover the very nature of the LISM and shed light on whether the Sun enters a new region in the LISM in the near future.In this presentation we give an overview of heliophysics science for the Interstellar Probe mission focusing on the critical science questions of the three objectives for the mission. We will discuss in more details a need for direct measurements in the LISM uniquely enabled by the Interstellar Probe.

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Efficient Access to Aliphatic Esters by Photocatalyzed Alkoxycarbonylation of Alkenes

10.21203/rs.3.rs-329273/v1 ◽

2021 ◽

Author(s):

Jian-Qiang Chen ◽

Xiaodong Tu ◽

Qi Tang ◽

Ke Li ◽

Liang Xu ◽

...

Keyword(s):

Natural Product ◽

Oxalyl Chloride ◽

Biologically Active ◽

Formal Synthesis ◽

Efficient Access ◽

Wide Range ◽

New Strategy ◽

Aliphatic Esters ◽

First Time

Abstract Aliphatic esters are essential constituents of biologically active compounds and versatile chemical intermediates for the synthesis of drugs. However, their preparation from readily available olefins remains challenging. In this report, a new strategy to access aliphatic esters from olefins through a unique photocatalyzed alkoxycarbonylation reaction is described. Alkyloxalyl chlorides, generated in situ from the corresponding alcohols and oxalyl chloride, are engaged for the first time as alkoxycarbonyl radical fragments under photoredox catalysis. This transformation tolerates a broad scope of electron-rich and electron-deficient olefins and provides the corresponding β-chloro esters in good yields. Additionally, a formal β-selective alkene alkoxycarbonylation is developed. And, a variety of oxindole-3-acetates and furoindolines are prepared in good to excellent yields. A more concise formal synthesis of (±)-physovenine is accomplished as well. With these strategies, a wide range of natural-product-derived olefins and alkyloxalyl chlorides are also successfully employed.

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A Novel Injectable Chitosan Sponge Containing Brain Derived Neurotrophic Factor (BDNF) to Enhance Human Oligodendrocyte Progenitor Cells' (OPC) Differentiation

MRS Proceedings ◽

10.1557/opl.2014.71 ◽

2014 ◽

Vol 1621 ◽

pp. 127-132

Author(s):

Mina Mekhail ◽

Qiao-Ling Cui ◽

Guillermina Almazan ◽

Jack Antel ◽

Maryam Tabrizian

Keyword(s):

Progenitor Cells ◽

Spinal Cord Injuries ◽

Cell Types ◽

Therapeutic Modality ◽

Oligodendrocyte Progenitor Cells ◽

High Porosity ◽

Oligodendrocyte Progenitor ◽

Wide Range ◽

First Time

ABSTRACTWe developed a rapidly-gelling chitosan sponge crosslinked with Guanosine 5'-Diphosphate (GDP). GDP has not been previously explored as an anionic crosslinker, and it was used in this application since the nucleoside guanosine has been shown to improve remyelination in situ, and thus its presence in the sponge composition was hypothesized to induce Oligodendrocyte Progenitor Cells' (OPC) differentiation. In addition to the chemical composition tailored to target OPCs, the developed chitosan sponge possesses a wide range of desirable physicochemical properties such as: rapid gelation, high porosity with interconnected pores, moduli of elasticity resembling that of soft tissue and cytocompatibility with many cell types. Moreover, protein encapsulation into the sponges was possible with high encapsulation efficiencies (e.g. BMP-7 and NT-3). In this study, BDNF was encapsulated in the chitosan sponges with an encapsulation efficiency greater than 80% and a sustained release over a 16-day period was achieved. We demonstrate here for the first time, the attachment of human fetal OPCs to the sponges and their differentiation after 12 days of culture. Overall, this newly-introduced injectable sponge is a promising therapeutic modality that can be used to enhance remyelination post-spinal cord injuries.

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Azoacetylenes for the Synthesis of Arylazotriazole Photoswitches

10.26434/chemrxiv.14742945 ◽

2021 ◽

Author(s):

Patrick Pfaff ◽

Felix Anderl ◽

Moritz Fink ◽

Moritz Balkenhohl ◽

Erick Carreira

Keyword(s):

Natural Products ◽

Arachidonic Acid ◽

Modular Approach ◽

Complex Molecules ◽

Design And Synthesis ◽

Wide Range ◽

Potential Applications ◽

First Time ◽

Oriented Approach

We report a modular approach towards novel arylazotriazole photoswitches and their photophysical characterization. Addition of lithiated TIPS-acetylene to aryldiazonium tetrafluoroborate salts gives a wide range of azoacetylenes, constituting an underexplored class of stable intermediates. In situ desilylation transiently leads to terminal arylazoacetylenes that undergo copper-catalyzed cycloadditions (CuAAC) with a diverse collection of organoazides. These include complex molecules derived from natural products or drugs, such as colchicine, taxol, tamiflu, and arachidonic acid. The arylazotriazoles display near-quantitative photoisomerization and long thermal Z-half-lives. Using the method, we introduce for the first time the design and synthesis of a diacetylene platform that permits implementation of a consecutive and diversity-oriented approach linking two different conjugants to independently addressable acetylenes within a common photoswitchable azotriazole. This is showcased in the synthesis of several photoswitchable conjugates, with potential applications as photoPROTACs and photoswitchable biotin conjugates

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Azoacetylenes for the Synthesis of Arylazotriazole Photoswitches

10.26434/chemrxiv.14742945.v1 ◽

2021 ◽

Author(s):

Patrick Pfaff ◽

Felix Anderl ◽

Moritz Fink ◽

Moritz Balkenhohl ◽

Erick Carreira

Keyword(s):

Natural Products ◽

Arachidonic Acid ◽

Modular Approach ◽

Complex Molecules ◽

Design And Synthesis ◽

Wide Range ◽

Potential Applications ◽

First Time ◽

Oriented Approach

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Epi-fluorescence Microscopy of Single Molecule DNA Denaturation in situ

10.1101/368423 ◽

2018 ◽

Author(s):

Pulkit Sharma

Keyword(s):

Single Molecule ◽

In Situ Hybridisation ◽

Fluorescence In Situ Hybridisation ◽

Experimental Conditions ◽

Target Dna ◽

Short Probe ◽

Fibre Fish ◽

First Time

AbstractDNA can be denatured by two main methods which are: a) denaturation in solution (invitro) and b) denaturation on a slide surface (in-situ). Additionally, DNA can also be denatured in gels with urea. The method to be used depends on various factors such as the application, the source of the DNA, the length, and the techniques available to confirm the extent of denaturation. Verification of the extent of denaturation is important because of the following factors: 1) increases the chances of hybridization (especially for short probes), 2) prevents the loss of expensive probes (if the target site is not denatured then, the probes will not hybridize and will only cause a high a background), 3) a higher degree of denaturation allows for more probes to be used and therefore, more information can be derived after hybridization, and 4) essential to maximize due to extremely short probe length. It is important to ensure that DNA morphology is preserved after denaturation in order for the probes to hybridise and also for ensuring proper statistical analysis for high throughput applications. In this work, various experimental conditions for in situ denaturation of single molecule DNA is presented.Significance StatementThe significance of this work is that it emphasizes on the importance of denaturation of target genomic DNA in DNA fibre FISH (fluorescence in situ hybridisation) experiments. If the quality of the target DNA is poor after denaturation or the target DNA is not properly denatured, then it will be very difficult or impossible to hybridize the probe DNA during FISH experiments. This will affect the final results for DNA FISH. Additionally, it is the first time that single DNA combed molecules have been shown to be denatured in situ. Most of the past work has been on gels only. Thus the work is both unique and significant.

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Monitoring Dynamic Recrystallisation in Bioresorbable Alloy Mg-1Zn-0.2Ca by Means of an In Situ Acoustic Emission Technique

Materials ◽

10.3390/ma15010328 ◽

2022 ◽

Vol 15 (1) ◽

pp. 328

Author(s):

Dmitry Merson ◽

Mikhail Linderov ◽

Alexander Brilevsky ◽

Alexey Danyuk ◽

Alexei Vinogradov

Keyword(s):

Acoustic Emission ◽

In Situ Monitoring ◽

Tensile Behaviour ◽

Median Frequency ◽

Fine Grained ◽

Specific Behaviour ◽

Wide Range ◽

Dynamic Recrystallisation ◽

First Time

The tensile behaviour of the biocompatible alloy Mg-1Zn-0.2Ca (in wt.%) in the fine-grained state, obtained by severe plastic deformation via multiaxial isothermal forging, has been investigated in a wide range of temperatures (20 ÷ 300) °C and strain rates (5 × 10−4 ÷ 2 × 10−2) s−1 with the measurements of acoustic emission (AE). The dependences of mechanical properties, including the yield stress, ultimate strength, ductility, and the strain-hardening rate, on the test temperature and strain rate, were obtained and discussed. It is shown for the first time that an acoustic emission method is an effective tool for in situ monitoring of the dynamic recrystallisation (DRX) process. The specific behaviour of the acoustic emission spectral density reflected by its median frequency as a function of strain at various temperatures can serve as an indicator of the DRX process’s completeness.

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“Dehalococcoides” sp. Strain CBDB1 Extensively Dechlorinates the Commercial Polychlorinated Biphenyl Mixture Aroclor 1260

Applied and Environmental Microbiology ◽

10.1128/aem.00102-09 ◽

2009 ◽

Vol 75 (13) ◽

pp. 4516-4524 ◽

Cited By ~ 92

Author(s):

Lorenz Adrian ◽

Vlasta Dudková ◽

Katařina Demnerová ◽

Donna L. Bedard

Keyword(s):

New York ◽

Polychlorinated Biphenyl ◽

Hudson River ◽

Pcb Congeners ◽

Aroclor 1248 ◽

Wide Range ◽

High Resolution Gas Chromatography ◽

Pcb Dechlorination ◽

First Time

ABSTRACT “Dehalococcoides” sp. strain CBDB1 in pure culture dechlorinates a wide range of PCB congeners with three to eight chlorine substituents. Congener-specific high-resolution gas chromatography revealed that CBDB1 extensively dechlorinated both Aroclor 1248 and Aroclor 1260 after four months of incubation. For example, 16 congeners comprising 67.3% of the total PCBs in Aroclor 1260 were decreased by 64%. We confirmed the dechlorination of 43 different PCB congeners. The most prominent dechlorination products were 2,3′,5-chlorinated biphenyl (25-3-CB) and 24-3-CB from Aroclor 1248 and 235-25-CB, 25-25-CB, 24-25-CB, and 235-236-CB from Aroclor 1260. Strain CBDB1 removed flanked para chlorines from 3,4-, 2,4,5-, and 3,4,5-chlorophenyl rings, primarily para chlorines from 2,3,4,5-chlorophenyl rings, primarily meta chlorines from 2,3,4- and 2,3,4,6-chlorophenyl rings, and either meta or para chlorines from 2,3,4,5,6-chlorophenyl rings. The site of attack on the 2,3,4-chorophenyl ring was heavily influenced by the chlorine configuration on the opposite ring. This dechlorination pattern matches PCB Process H dechlorination, which was previously observed in situ both in the Acushnet Estuary (New Bedford, MA) and in parts of the Hudson River (New York). Accordingly, we propose that Dehalococcoides bacteria similar to CBDB1 are potential agents of Process H PCB dechlorination in the environment. This is the first time that a complex naturally occurring PCB dechlorination pattern has been reproduced in the laboratory using a single bacterial strain.

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In-situ electrical-resistivity measurements in the high-voltage electron microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100107484 ◽

1978 ◽

Vol 36 (1) ◽

pp. 68-69

Author(s):

W. E. King

Keyword(s):

Electrical Resistivity ◽

Electron Microscope ◽

High Voltage ◽

Resistivity Measurements ◽

Voltage Electron ◽

High Voltage Electron Microscope ◽

High Voltage Electron ◽

Wide Range ◽

Helium Gas

A side-entry type, helium-temperature specimen stage that has the capability of in-situ electrical-resistivity measurements has been designed and developed for use in the AEI-EM7 1200-kV electron microscope at Argonne National Laboratory. The electrical-resistivity measurements complement the high-voltage electron microscope (HVEM) to yield a unique opportunity to investigate defect production in metals by electron irradiation over a wide range of defect concentrations.A flow cryostat that uses helium gas as a coolant is employed to attain and maintain any specified temperature between 10 and 300 K. The helium gas coolant eliminates the vibrations that arise from boiling liquid helium and the temperature instabilities due to alternating heat-transfer mechanisms in the two-phase temperature regime (4.215 K). Figure 1 shows a schematic view of the liquid/gaseous helium transfer system. A liquid-gas mixture can be used for fast cooldown. The cold tip of the transfer tube is inserted coincident with the tilt axis of the specimen stage, and the end of the coolant flow tube is positioned without contact within the heat exchanger of the copper specimen block (Fig. 2).

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Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

10.26434/chemrxiv.7098695 ◽

2018 ◽

Author(s):

Elaine A. Kelly ◽

Judith E. Houston ◽

Rachel Evans

Keyword(s):

Real Time ◽

Absorption Spectroscopy ◽

Self Assembly ◽

Uv Light ◽

Wormlike Micelles ◽

Tetraethylene Glycol ◽

Light Illumination ◽

First Time ◽

Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such asdrug delivery and micellar catalysis. Currently, their behaviour in the equilibrium cis-and trans-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C8AzoOC8E4) using small-angle neutron scattering (SANS). We show that the incorporation of in-situUV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C8AzoOC8E4could switch between wormlike micelles (transnative state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked in-situthrough combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

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