General method for cloning Neurospora crassa nuclear genes by complementation of mutants

1985 ◽  
Vol 5 (9) ◽  
pp. 2272-2278
Author(s):  
R A Akins ◽  
A M Lambowitz
Keyword(s):  
Neurospora Crassa ◽  
Genomic Library ◽  
Selection Procedure ◽  
Nuclear Genes ◽  
Shuttle Vectors ◽  
Sib Selection ◽  
First Time ◽  
Very High ◽  
Restriction Site Polymorphisms ◽  
General Method

We have developed a sib selection procedure for cloning Neurospora crassa nuclear genes by complementation of mutants. This procedure takes advantage of a modified N. crassa transformation procedure that gives as many as 10,000 to 50,000 stable transformants per microgram of DNA with recombinant plasmids containing the N. crassa qa-2+ gene. Here, we describe the use of the sib selection procedure to clone genes corresponding to auxotrophic mutants, nic-1 and inl. The identities of the putative clones were confirmed by mapping their chromosomal locations in standard genetic crosses and using restriction site polymorphisms as genetic markers. Because we can obtain very high N. crassa transformation frequencies, cloning can be accomplished with as few as five subdivisions of an N. crassa genomic library. The sib selection procedure should, for the first time, permit the cloning of any gene corresponding to an N. crassa mutant for which an appropriate selection can be devised. Analogous procedures may be applicable to other filamentous fungi before the development of operational shuttle vectors.

scholarly journals General method for cloning Neurospora crassa nuclear genes by complementation of mutants.

1985 ◽  
Vol 5 (9) ◽  
pp. 2272-2278 ◽  
Author(s):  
R A Akins ◽  
A M Lambowitz
Keyword(s):  
Neurospora Crassa ◽  
Genomic Library ◽  
Selection Procedure ◽  
Nuclear Genes ◽  
Shuttle Vectors ◽  
Sib Selection ◽  
First Time ◽  
Very High ◽  
Restriction Site Polymorphisms ◽  
General Method

We have developed a sib selection procedure for cloning Neurospora crassa nuclear genes by complementation of mutants. This procedure takes advantage of a modified N. crassa transformation procedure that gives as many as 10,000 to 50,000 stable transformants per microgram of DNA with recombinant plasmids containing the N. crassa qa-2+ gene. Here, we describe the use of the sib selection procedure to clone genes corresponding to auxotrophic mutants, nic-1 and inl. The identities of the putative clones were confirmed by mapping their chromosomal locations in standard genetic crosses and using restriction site polymorphisms as genetic markers. Because we can obtain very high N. crassa transformation frequencies, cloning can be accomplished with as few as five subdivisions of an N. crassa genomic library. The sib selection procedure should, for the first time, permit the cloning of any gene corresponding to an N. crassa mutant for which an appropriate selection can be devised. Analogous procedures may be applicable to other filamentous fungi before the development of operational shuttle vectors.

scholarly journals Shell-crossing in a ΛCDM Universe

2020 ◽  
Vol 501 (1) ◽  
pp. L71-L75
Author(s):  
Cornelius Rampf ◽  
Oliver Hahn
Keyword(s):  
Dark Matter ◽  
Perturbation Theory ◽  
Large Scale ◽  
Cold Dark Matter ◽  
Three Dimensional ◽  
Random Initial Data ◽  
Recursion Relations ◽  
Indispensable Tool ◽  
First Time ◽  
Very High

ABSTRACT Perturbation theory is an indispensable tool for studying the cosmic large-scale structure, and establishing its limits is therefore of utmost importance. One crucial limitation of perturbation theory is shell-crossing, which is the instance when cold-dark-matter trajectories intersect for the first time. We investigate Lagrangian perturbation theory (LPT) at very high orders in the vicinity of the first shell-crossing for random initial data in a realistic three-dimensional Universe. For this, we have numerically implemented the all-order recursion relations for the matter trajectories, from which the convergence of the LPT series at shell-crossing is established. Convergence studies performed at large orders reveal the nature of the convergence-limiting singularities. These singularities are not the well-known density singularities at shell-crossing but occur at later times when LPT already ceased to provide physically meaningful results.

Development of Operating Temperature Prediction Method Using Thermophysical Properties Change of Thermal Barrier Coatings

2004 ◽  
Vol 126 (1) ◽  
pp. 102-106 ◽  
Author(s):  
T. Fujii ◽  
T. Takahashi
Keyword(s):  
Thermal Conductivity ◽  
Thermal Barrier Coatings ◽  
Operating Temperature ◽  
Thermal Barrier ◽  
Conductivity Measurements ◽  
Barrier Coatings ◽  
Barrier Performance ◽  
Very High ◽  
General Method ◽  
Exposure Conditions

Thermal barrier coatings (TBCs) have become an indispensable technology as the temperature of turbine inlet gas has increased. TBCs reduce the temperature of the base metal, but a reduction of internal pores by sintering occurs when using TBCs, and so the thermal barrier performance of TBCs is deteriorated. This in turn increases the temperature of the base metal and could shorten its lifespan. The authors have already clarified by laboratory acceleration tests that the deterioration of the thermal barrier performance of TBCs is caused by a decrease in the noncontact area that exists inside TBCs. This noncontact area is a slit space that exists between thin layers and is formed when TBCs are coated. This paper examines the relations between the decrease of the noncontact area and the exposure conditions, by measuring the thermal conductivity and the porosity of TBCs exposed to the temperatures that exist in an actual gas turbine, and derives the correlation with exposure conditions. As a result, very high correlations were found between the thermal conductivity and exposure conditions of TBCs, and between the porosity and exposure conditions. A very high correlation was also found between the thermal conductivity and porosity of TBCs. In addition, techniques for predicting TBC operating temperature were examined by using these three correlations. The correlation of diameter and exposure conditions of the gamma prime phase, which exists in nickel base super alloys, is used as a general method for predicting the temperature of parts in hot gas paths. This paper proposes two kinds of operating temperature prediction methods, which are similar to this general method. The first predicts the operating temperature from thermal conductivity measurements of TBCs before and after use, and the second predicts the operating temperature from thermal conductivity measurements of TBCs after use and porosity measurements before use. The TBC operating temperatures of a combustor that had been used for 12,000 hours with an actual E-class gas turbine were predicted by these two methods. The advantage of these methods is that the temperature of all parts with TBC can be predicted.

scholarly journals Visible AO Observations at Halpha for Accreting Young Planets

2013 ◽  
Vol 8 (S299) ◽  
pp. 32-33
Author(s):  
L.M. Close ◽  
K. Follette ◽  
J.R. Males ◽  
K. Morzinski ◽  
T.J. Rodigas ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Binary Stars ◽  
Optical Resolution ◽  
Ccd Camera ◽  
Short Exposure ◽  
Low Mass ◽  
Orion Trapezium ◽  
First Time ◽  
Adaptive Optics System ◽  
Very High

AbstractWe utilized the new high-order (250-378 mode) Magellan Adaptive Optics system (MagAO) to obtain very high-resolution science in the visible with MagAO's VisAO CCD camera. In the good-median seeing conditions of Magellan (0.5–0.7″) we find MagAO delivers individual short exposure images as good as 19 mas optical resolution. Due to telescope vibrations, long exposure (60s) r' (0.63μm) images are slightly coarser at FWHM = 23-29 mas (Strehl ~ 28%) with bright (R < 9 mag) guide stars. These are the highest resolution filled-aperture images published to date. Images of the young (~ 1 Myr) Orion Trapezium θ1 Ori A, B, and C cluster members were obtained with VisAO. In particular, the 32 mas binary θ1 Ori C1C2 was easily resolved in non-interferometric images for the first time. Relative positions of the bright trapezium binary stars were measured with ~ 0.6–5 mas accuracy. In the second commissioning run we were able to correct 378 modes and achieved good contrasts (Strehl>20% on young transition disks at Hα). We discuss the contrasts achieved at Hα and the possibility of detecting low mass (~ 1–5 Mjup) planets (past 5AU) with our new SAPPHIRES survey with MagAO at Hα.

scholarly journals Expression of Heterologous Cellulases inThermotogasp. Strain RQ2

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Hui Xu ◽  
Dongmei Han ◽  
Zhaohui Xu
Keyword(s):  
Enzyme Activities ◽  
Bacterial Cells ◽  
Recombinant Enzymes ◽  
Caldicellulosiruptor Saccharolyticus ◽  
Shuttle Vectors ◽  
E Coli ◽  
Chimeric Enzymes ◽  
Coding Regions ◽  
First Time ◽  
Culture Supernatants

The ability ofThermotogaspp. to degrade cellulose is limited due to a lack of exoglucanases. To address this deficiency, cellulase genes Csac_1076 (celA) and Csac_1078 (celB) fromCaldicellulosiruptor saccharolyticuswere cloned intoT.sp. strain RQ2 for heterologous overexpression. Coding regions of Csac_1076 and Csac_1078 were fused to the signal peptide of TM1840 (amyA) and TM0070 (xynB), resulting in three chimeric enzymes, namely, TM1840-Csac_1078, TM0070-Csac_1078, and TM0070-Csac_1076, which were carried byThermotoga-E. colishuttle vectors pHX02, pHX04, and pHX07, respectively. All three recombinant enzymes were successfully expressed inE. coliDH5αandT.sp. strain RQ2, rendering the hosts with increased endo- and/or exoglucanase activities. InE. coli, the recombinant enzymes were mainly bound to the bacterial cells, whereas inT.sp. strain RQ2, about half of the enzyme activities were observed in the culture supernatants. However, the cellulase activities were lost inT.sp. strain RQ2 after three consecutive transfers. Nevertheless, this is the first time heterologous genes bigger than 1 kb (up to 5.3 kb in this study) have ever been expressed inThermotoga, demonstrating the feasibility of using engineeredThermotogaspp. for efficient cellulose utilization.

An Effective Synthesis of N,N-Diphenyl Carbazolium Salts

Synlett ◽  
2017 ◽  
Vol 29 (10) ◽  
pp. 1314-1318 ◽  
Author(s):  
Charles Diesendruck ◽  
Sinai Aharonovich ◽  
Nansi Gjineci ◽  
Dario Dekel
Keyword(s):  
Positive Charge ◽  
Quaternary Ammonium Salts ◽  
Simple Approach ◽  
Ammonium Salts ◽  
State Structure ◽  
Pi Systems ◽  
Effective Synthesis ◽  
Short Time ◽  
First Time ◽  
General Method

Tetraaryl ammonium salts are a synthetic challenge, since there is no general method for the arylation of triaryl amines. Contrary to other quaternary ammonium salts, tetraaryl ammonium salts should be very chemically stable. The ipso carbons are not very electrophilic, since the positive charge is distributed throughout the pi systems and they have no acidic β hydrogens. Here we demonstrate a simple approach to N,N-diphenyl carbazolium salts using only three synthetic steps, allowing for an easy production of these salts in large amounts and in a relatively short time. In addition, we study the Cu(I) catalyzed multi-arylation of 2,2’-diaminobiphenyl, focusing on the regioselectivity of each step. Finally, we characterize, for the first time, the solid state structure of a tetraaryl ammonium salt.

scholarly journals Gold in Irish Coal: Palaeo-Concentration from Metalliferous Groundwaters

Minerals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 635
Author(s):  
Liam A. Bullock ◽  
John Parnell ◽  
Joseph G.T. Armstrong ◽  
Magali Perez ◽  
Sam Spinks
Keyword(s):  
Heat Flow ◽  
Low Temperature ◽  
Precious Metals ◽  
High Heat ◽  
Selenium Content ◽  
Foreland Basins ◽  
High Heat Flow ◽  
South Wales ◽  
First Time ◽  
Very High

Gold grains, up to 40 μm in size and containing variable percentages of admixed platinum, have been identified in coals from the Leinster Coalfield, Castlecomer, SE Ireland, for the first time. Gold mineralisation occurs in sideritic nodules in coals and in association with pyrite and anomalous selenium content. Mineralisation here may have reflected very high heat flow in foreland basins north of the emerging Variscan orogenic front, responsible for gold occurrence in the South Wales Coalfield. At Castlecomer, gold (–platinum) is attributed to precipitation with replacive pyrite and selenium from groundwaters at redox interfaces, such as siderite nodules. Pyrite in the cores of the nodules indicates fluid ingress. The underlying Caledonian basement bedrock is mineralised by gold, and thus likely provided a source for gold. The combination of the gold occurrences in coal in Castlecomer and in South Wales, proximal to the Variscan orogenic front, suggests that these coals along the front could comprise an exploration target for low-temperature concentrations of precious metals.

scholarly journals First evaluation of coral recruitment in Madagascar

2021 ◽  
Vol 20 (1) ◽  
pp. 47-62
Author(s):  
Gildas G.B. Todinanahary ◽  
Nomeniarivelo Hasintantely ◽  
Igor Eeckhaut ◽  
Thierry Lavitra
Keyword(s):  
Larval Density ◽  
Average Density ◽  
Recruitment Rate ◽  
Seasonal Distribution ◽  
Coral Recruitment ◽  
Significant Difference ◽  
Southwest Region ◽  
The Mean ◽  
First Time ◽  
Very High

The distribution of larvae and recruitment of scleractinians in the southwest region of Madagascar were evaluated for the first time between October 2013 and September 2014 at 3 sites. The presence of coral larvae (planulae) was monitored through weekly sampling using a plankton net and the recruitment rate evaluated by monthly sampling of the newly settled corals (<1 year stage) on recruitment tiles and by a monitoring of the recruitment of juveniles (1< Juveniles < 2 years) using the quadrat method. Planulae were present in the plankton for 9 months during the survey. The recorded mean annual density of planula varied from 0.43 ± 0.41 larvae m-3 to 3.23 ± 5.72 larvae m-3 depending on site, with a peak in larval density towards the end of November and the beginning of December. The variability in the occurrence of planula is very high and implied that the density observed in the year does not present a significant difference between the sites (pKW=0.33). The average density of total recruits was 620.13 ± 621.30 recruits m-2, 40.28 ± 50.97 recruits m-2 and 36.34 ± 33.82 recruits m-2, respectively at the sites of Nosy Tafara, Grande Vasque and Rose Garden. Seasonal distribution of coral recruitment was different between the sites. The mean annual density of newly settled recruits (< 1 month stage) was significantly higher at Nosy Tafara with 94.91±101.08 recruits m-2 compared to Grande Vasque and Rose Garden with 18.75±34.32 recruits m-2 and 11.57±18.47 recruits m-2 (pKW<0.001), respectively. The highest density of newly settled recruits was observed between October to December. Higher density of recruits was also observed in March at Nosy Tafara and in May at all three sites. Results of juvenile monitoring showed high rates (> 10 juveniles m-2) compared to other regions and the threshold, but it revealed high mortality among recruits. Coral recruitment in the southwest region of Madagascar was found to be high and could result in increased resilience of the coral reef assemblages.

scholarly journals Clippers (Chronic Lymphocytic Inflammation with Pontine Perivascular Enhancement Responsive to Steroids) Management Experience at a single Third-level Medical Center in México.

2021 ◽  
Vol 8 (2) ◽  
pp. 01-07
Author(s):  
Brenda Bertado Cortes ◽  
Brian Madariaga Cortes ◽  
Massiel Zenteno Zenteno ◽  
Bayron Alexander Sandoval Bonilla
Keyword(s):  
Stereotactic Biopsy ◽  
Medical Center ◽  
Medical Personnel ◽  
The Central Nervous System ◽  
Management Experience ◽  
Magnetic Resonance Imaging Mri ◽  
Salt And Pepper ◽  
First Contact ◽  
First Time ◽  
Very High

Chronyc lymphosytic inflammation with pontine perivascular enhacement responsive to steroids (CLIPPERS), described for the first time in 2010 by Pittock and collaborators, is a rare inflammatory disease of the central nervous system (SNC) characterized by the presence of punctuate or curvilinear lesions described like “salt and pepper” appearance on the magnetic resonance imaging (MRI), that enhance with Gadoliniumn administration; this lesions show an exquisite response to corticosteroid therapy. The etiology of this disease remains unknown. However, the existing articles suggest an autoimmune component, which may or may not be related to other autoinmmune, infectious or malignant pathologies. Due to the above, it is generally considered that in order to reach the diagnosis of CLIPPERS, the possibility of other more common or aggressive pathologies must first be ruled out through extensive investigation. However, if the clinical and imaging presentation are typical and there is a very high suspicion of CLIPPERS, early initiation of glucosteroid therapy may be recommended. There is no unanimous therapy plan due to the few cases reported worldwide thus far. In cases of severe relapses or atypical behavior, both clinical and radiological, it is recommended to consider a stereotactic biopsy of the lesion to integrate the definitive diagnosis. Because it is a rare disease, it is relatively unknown to first- contact medical personnel; in our particular case, this leads to referral to the neurosurgery department who, thanks to their experience, have considered a demilinizing disease as a diagnostic possibility and requested an assessment by the neurology department. Here, we report the evolution and management of three diagnosed cases of CLIPPERS at a single Third-level Medical Center in México; based on clinical, radiological and neuropathological findings; as well as highlighting the importance of lesion biopsy in selected cases.

scholarly journals Methyl Salicylate Glycosides in Some Italian Varietal Wines

Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3260 ◽  
Author(s):  
Carlin ◽  
Masuero ◽  
Guella ◽  
Vrhovsek ◽  
Mattivi
Keyword(s):  
Methyl Salicylate ◽  
Total Concentration ◽  
Plant Secondary Metabolites ◽  
Point Of View ◽  
1H And 13C Nmr ◽  
Vitis Riparia ◽  
13C Nmr Analysis ◽  
First Time ◽  
Gaultheria Procumbens ◽  
Very High

Glycosides are ubiquitous plant secondary metabolites consisting of a non-sugar component called an aglycone, attached to one or more sugars. One of the most interesting aglycones in grapes and wine is methyl salicylate (MeSA), an organic ester naturally produced by many plants, particularly wintergreens. To date, nine different MeSA glycosides from plants have been reported, mainly spread over the genera Gaultheria, Camellia, Polygala, Filipendula, and Passiflora. From a sensorial point of view, MeSA has a balsamic-sweet odor, known as Wintergreen. MeSA was found in Vitis riparia grapes, in Vitis vinifera sp. and in the Frontenac interspecific hybrid. We found that the MeSA glycosides content in Verdicchio wines and in some genetically related varieties (Trebbiano di Soave and Trebbiano di Lugana) was very high. In order to understand which glycosides were present in wine, the methanolic extract of Verdicchio wine was injected into a UPLC-Q-TOF-HDMS and compared to the extracts of different plants rich in such glycosides. Using pure standards, we confirmed the existence of two glycosides in wine: MeSA 2-O--d-glucoside and MeSA 2-O--d-xylopyranosyl (1-6) -d-glucopyranoside (gaultherin). For the first time, we also tentatively identified other diglycosides in wine: MeSA 2-O--l-arabinopyranosyl (1-6)--d-glucopyranoside (violutoside) and MeSA 2-O--d-apiofuranosyl (1-6)--d-glucopyranoside (canthoside A), MeSA 2-O--d-glucopyranosyl (1-6)-O--d-glucopyranoside (gentiobioside) and MeSA 2-O--l-rhamnopyranosyl (1-6)--d-glucopyranoside (rutinoside). Some of these glycosides have been isolated from Gaultheria procumbens leaves by preparative liquid chromatography and structurally annotated by 1H- and 13C-NMR analysis. Two of the peaks isolated from Gaultheria procumbens leaves, namely MeSA sambubioside and MeSA sophoroside, were herein observed for the first time. Six MeSA glycosides were quantified in 64 Italian white wines, highlighting the peculiar content and pattern in Verdicchio wines and related cultivars. The total concentration in bound and free MeSA in Verdicchio wines varied in the range of 456–9796 g/L and 5.5–143 g/L, respectively, while in the other wines the bound and free MeSA was below 363 g/L and 12 g/L, respectively. As this compound’s olfactory threshold is between 50 and 100 g/L, our data support the hypothesis that methyl salicylate can contribute to the balsamic scent, especially in old Verdicchio wines.

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