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Over the past years, several methods have been developed for gene cloning. Choosing a cloning strategy depends on various factors, among which simplicity and affordability have always been considered. The aim of this study, on the one hand, is to simplify gene cloning by skipping in vitro assembly reactions and, on the other hand, to reduce costs by eliminating relatively expensive materials. We investigated a cloning system using Escherichia coli harboring two plasmids, pLP-AmpR and pScissors-CmR. The pLP-AmpR contains a landing pad (LP) consisting of two genes (λ int and λ gam) that allow the replacement of the transformed linear DNA using site-specific recombination. After the replacement process, the inducible expressing SpCas9 and specific sgRNA from the pScissors-CmR (CRISPR/Cas9) vector leads to the removal of non-recombinant pLP-AmpR plasmids. The function of LP was explored by directly transforming PCR products. The pScissors-CmR plasmid was evaluated for curing three vectors, including the origins of pBR322, p15A, and pSC101. Replacing LP with a PCR product and fast-eradicating pSC101 origin-containing vectors was successful. Recombinant colonies were confirmed following gene replacement and plasmid curing processes. The results made us optimistic that this strategy may potentially be a simple and inexpensive cloning method. Key points: •The in vivo cloning was performed by replacing the target gene with the landing pad. •Fast eradication of non-recombinant plasmids was possible by adapting key vectors. •This strategy is not dependent on in vitro assembly reactions and expensive materials. [ABSTRACT FROM AUTHOR]

The accumulation of phase-transformation-induced strain during the direct thermoelastic martensitic transformation and structural strain in the course of loading under martensitic inelasticity conditions in three directions with respect to the rolling direction (0°, 45°, 90°) has been experimentally studied for a thin titanium nickelide plate. For the case of uniaxial tension, approximation functions are proposed to accurately describe direct transformation and martensitic inelasticity diagrams with stable values of material parameters. For all directions in the plate plane, the direct transformation diagram is located higher than the martensitic inelasticity diagram along the strain axis. [ABSTRACT FROM AUTHOR]

ABSTRACTSesame (Sesamum indicum L.) is an important oil crop and one of the oldest-known oil crops to humankind. Sesame has excellent nutritional and therapeutic properties; it is rich in important fatty acids, protein, fiber, and vital minerals. Oil percentage varies among different genotypes but generally accounts for more than 50% of the seed’s dry weight. To meet the increasing demand for vegetable oil production worldwide, expanding the cultivation of oil crops in newly reclaimed areas worldwide is essential. Molecular breeding is an expeditious approach for varietal improvement but requires efficient transgenesis. Published sesame transformation methods are highly genus-specific, tedious, and involve preparing and testing different media and explants. We produced transgenic sesame plants using a stable, noninvasive, and robust Agrobacterium tumefaciens transformation method. Leaves and flowers excised from the T0 plants at different developmental stages were PCR screened, and 61/93 seedlings were found to be PCR positive. T1 seeds resulting from two lines were germinated in a biocontainment greenhouse facility and screened using PCR, basta leaf painting, and spraying fully matured plants with basta herbicide (0.02 mg/l); non-transgenic segregants and control non-transgenic plants were severely damaged, and eventually died, while transgenic plants were not affected by the Basta spraying. RT-PCR on T1 plants indicated the presence of Bar transcripts in T1 progeny. Furthermore, RT-PCR using NPTII primers did not result in any amplification in transgenic sesame plants (NPTII is present in the vector but not in the T-DNA region) indicating that the transgenic sesame plants were not an Agrobacterium-contaminant.

A one-dimensional structural-simulation model for the deformation of shape memory alloys during thermoelastic phase transformations is used to describe the deformation change during the direct transformation under reversible stresses and the reversible shape memory effect. [ABSTRACT FROM AUTHOR]

A one-dimensional structural-simulation model is proposed to describe the deformation of shape memory alloys during thermoelastic phase transformations; it takes into account the nucleation and development of martensitic mesoelements during the direct transformation and their degradation and disappearance during the reverse transformation. An adequate description of the orientational transformation effects in terms of the model is demonstrated. [ABSTRACT FROM AUTHOR]

Based on the iron-based catalysts for direct synthesis of aromatics from syngas, the research progress of modified iron-based catalysts and iron-based zeolites composite catalysts was summarized, and the reaction mechanism was discussed; the coupling mode of the active components of the iron-based and zeolites composite catalyst, the modification of the iron-based catalyst, and the influence of the acidity and structural modification of the zeolites on the yield of aromatics were emphatically described; finally, the future research directions of iron-based catalysts were prospected. [ABSTRACT FROM AUTHOR]

Intertextuality, a term coined by Julia Kristeva, is a crucial aspect of all forms of creative expression, including literature, music, and art. The idea of intertextuality has been further expanded by Gérard Genette, who included intertextuality as one of the five aspects of the broader phenomenon of transtextuality. Among these several types is hypertextuality, which refers to the relationship between a text and its hypertextual extensions or variations. Within the scope of hypertextuality, Genette identified two methods of transforming a text A into a text B: direct and indirect transformation. This paper considers direct transformation. Although its primary association is with prose and poetry, it can also be extended to encompass song lyrics. In this article, several rock covers serve as examples of text B, and consideration is given to how they differ from their original counterparts (text A), albeit not in a musical form, but rather in terms of their lyrics. In the process, four different approaches were found for delivering a transformation of the original lyrics: fixed transformation, slight transformation, conversion of both the original meaning and lyrics, and considerable transformation. [ABSTRACT FROM AUTHOR]

Even though trait introgression for maize is relatively straightforward, conversion from a single germplasm source, native or gene edit, can greatly slow the development of commercial lines because the allele donor will also contribute undesirable parts of its genome (genetic drag) to the destination genome. Should evaluations of genome edits follow the GM assessment framework, which is event-based and can include comprehensive molecular, protein safety, environmental safety, and agronomic assessments, this will severely limit accessibility of important trait improvements and innovations to farmers and consumers even in a trait-based regulation environment due to the costly and heavy regulatory burden associated with GM approvals ([2]). How genome editing can fundamentally change the path for crop development Potential considerations for direct germplasm editing and trait-based regulation of genome edits One key consideration for trait-based regulation of genome edits is a rigorous product development pipeline. [Extracted from the article]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sesame (Sesamum indicum L.) is an important oil crop and one of the oldest-known oil crops to humankind. Sesame has excellent nutritional and therapeutic properties; it is rich in important fatty acids, protein, fiber, and vital minerals. Oil percentage varies among different genotypes but generally accounts for more than 50% of the seed's dry weight. To meet the increasing demand for vegetable oil production worldwide, expanding the cultivation of oil crops in newly reclaimed areas worldwide is essential. Molecular breeding is an expeditious approach for varietal improvement but requires efficient transgenesis. Published sesame transformation methods are highly genus-specific, tedious, and involve preparing and testing different media and explants. We produced transgenic sesame plants using a stable, noninvasive, and robust Agrobacterium tumefaciens transformation method. Leaves and flowers excised from the T0 plants at different developmental stages were PCR screened, and 61/93 seedlings were found to be PCR positive. T1 seeds resulting from two lines were germinated in a biocontainment greenhouse facility and screened using PCR, basta leaf painting, and spraying fully matured plants with basta herbicide (0.02 mg/l); non-transgenic segregants and control non-transgenic plants were severely damaged, and eventually died, while transgenic plants were not affected by the Basta spraying. RT-PCR on T1 plants indicated the presence of Bar transcripts in T1 progeny. Furthermore, RT-PCR using NPTII primers did not result in any amplification in transgenic sesame plants (NPTII is present in the vector but not in the T-DNA region) indicating that the transgenic sesame plants were not an Agrobacterium-contaminant. [ABSTRACT FROM AUTHOR]

The dependence of the stress of the onset of structural deformation of titanium nickelide on the degree of reverse phase transformation occurring after complete direct martensitic transformation is experimentally investigated. The experimental results are described qualitatively and quantitatively correctly in terms of a model, in which the maximum intrinsic inelastic strain intensity of the martensitic part of the representative volume of a shape memory alloy is used as an isotropic hardening parameter. [ABSTRACT FROM AUTHOR]

Copyright of Hydrographic Surveying & Charting / Haiyang Cehui is the property of Hydrographic Surveying & Charting Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract—The influence of the preliminary direct martensitic transformation in titanium nickelide under a constant compressive stress on the diagrams of subsequent loading under martensitic inelasticity at a monotonically increasing compressive stress is experimentally studied. These diagrams are found to reach the martensitic inelasticity diagram corresponding to the compression of initially fully twinned martensite when the stress increases. The cross hardening on compression is shown to be more intense than that on tension. The phase-structural strain deviator can be considered as a state parameter for a shape memory alloy. [ABSTRACT FROM AUTHOR]

Fe-catalyzed direct transformation of benzylic amines into carbonyl compounds was performed in H2 O. The reaction of benzylic amines with formaldehyde in the presence of FeCl3 ·6H2 O in H2 O afforded the corresponding carbonyl compounds (80 °C to reflux conditions; 14 examples, up to 94% yield). O18-labeling experiments indicated that the O atom in the generated carbonyl is derived from H2 O. [ABSTRACT FROM AUTHOR]

The deformation of titanium nickelide specimens in loading under the conditions of martensite inelasticity and direct martensitic transformation during uniaxial compression and tension is experimentally studied. The experimental results can be used to determine two material functions for a nonlinear deformation model for a shape memory alloy. The experimental data are found to be approximated best of all when cumulative γ distribution functions are applied. [ABSTRACT FROM AUTHOR]

An improved direct transformation method via particle bombardment of split-immature zygotic embryo explants with intact embryonic axis is reported. This method involves abiotic stress (cold treatment and plasmolysis) treatments of explants prepared from immature embryos of 8-10 mm size for improved somatic embryogeneis. Transgenic events were produced using optimized bombardment conditions and selection with hygromycin or glufosinate. Transgenic somatic embryos developed within as little as 4 weeks after bombardment of explants. Transgenic plants were regenerated 4-5 months after bombardment and the entire process from bombardment to T1 seed production took 7-9 months. Plants regenerated from the system were fertile and showed more than 90% heritability of the transgene to the next generation. Transformation frequencies of 5.4 and 2.7% (based on the number of bombarded split-immature embryo explants) were observed with hygromycin and glufosinate selection, respectively. [ABSTRACT FROM AUTHOR]

Background: Capsicum is a genus of an important spice crop that belongs to the chili lineage. However, many Capsicum species (family Solanaceae) are known to be recalcitrant to genetic transformation and in vitro regeneration, thus hampering the effort in using Capsicum species for detailed biological investigation. In this study, we have developed an optimized protocol for the direct transformation of Capsicum frutescens L. cv. Hot Lava using a biolistic particle delivery system. In addition, a procedure for in vitro whole plant regeneration from the hypocotyl explants of C. frutescens was established. Results: In this study on the biolistic system, explant target distance, bombardment helium(He) pressure, and the size of the microcarrier were the key parameters to be investigated. The optimized parameters based on the screening of GFP expression were determined to have a target distance of 6 cm, helium pressure of 1350 psi, and gold particle (microcarrier) size of 1.6 μm. The greatest number of shoots was obtained from hypocotyls as explants using Murashige and Skoog medium supplemented with 5.0-mg/L 6-benzylaminopurine and 0.1-mg/L 1-naphthaleneacetic acid. On an average, five shoots per explant were formed, and of them, one shoot managed to form the root and developed into a whole plant. Conclusions:We obtained an optimized protocol for the biolistic transformation of chili and in vitro regeneration of chili plantlets. The establishment of the protocols will provide a platform for molecular breeding and biological studies of chili plants. [ABSTRACT FROM AUTHOR]

Using a turbostratic pyrolytic boron nitride as a starting material, we synthesized a variety of ultrahard polycrystalline cubic boron nitride (PcBN) as a function of the heating duration changing from 1 to 60 min under a constant temperature and pressure conditions (1950 °C and 25 GPa) using a multi-anvil apparatus. When the heating duration was less than 13 min, ultrafine nano-polycrystalline cBN (U-NPcBN) with the mean grain size of <50 nm was produced. Among these U-NPcBNs those synthesized with 11–13 min were found to have a uniform texture composed purely of cBN (i.e. with no wurzite BN residue) and a Knoop hardness of >53 GPa, which is 20% higher than that of the hardest conventional binderless PcBN in practical use. Furthermore, the PcBNs synthesized with 18–20 min showed a unique nanocrystalline texture composed of relatively coarse grains dispersed in a fine grained matrix and even higher Knoop hardness (54.5–55.2 GPa). [ABSTRACT FROM AUTHOR]

Agrobacterium tumefaciens is a widely used microbial tool in plant molecular biology to transfer DNA into plant cells and produce, e.g., stable or transient transformants or induce gene silencing. In our study, we present a simplified version of electrocompetent cell preparation that is not only time and cost efficient, but it requires minimal handling of bacterial cells. Liquid cultures are normally used to prepare competent Agrobacterium cells. To overcome the difficulties of working with liquid cultures, we propose suspending bacterial cells directly from overnight agar plate cultures. In addition, we optimized several parameters to simplify the procedure and maximize the number of transformants (e.g., Agrobacterium strains, number of washing steps, amount of required plasmid DNA, electroporation parameters, type of incubation media, or incubation time). This optimized, simple, and fast protocol has proved to be efficient enough to obtain transformed colonies with low amounts (as little as 1 ng) of plasmid DNA. In addition, it also enabled us to introduce ligated plasmids directly into Agrobacterium omitting the E. coli transformation step and accelerating the cloning procedure further. [ABSTRACT FROM AUTHOR]

Using a turbostratic pyrolytic boron nitride produced by a chemical vapor deposition process as a starting material, we conducted experiments for synthesizing polycrystalline cubic boron nitride (PcBN) at a temperature of 1600–2600 °C and pressure of 25 GPa with a multi-anvil high-pressure apparatus. Moreover, we evaluated the microstructure and hardness characteristics of the synthesized PcBN. The results showed that a complete single-phase PcBN without residual wurtzite BN was produced at 1900 °C or higher and a nano-polycrystalline cBN (NPcBN) having a mean grain size smaller than 100 nm could be synthesized at a temperature of 1950 °C or lower under a pressure of 25 GPa. Furthermore, we found that a single-phase NPcBN (CGD-NPcBN) having a characteristic microstructure of dispersed relatively coarse grains in a fine polycrystalline structure, which was harder than 53.5 GPa in Knoop hardness, was produced at a temperature range of 1900–1950 °C. In particular, at 1950 °C, CGD-NPcBN having a Knoop hardness of 54.7 GPa, which is 25% higher than that of the hardest binderless PcBN tool currently in practical use, can be synthesized. In addition, we verified that the Knoop hardness of the single-phase PcBN with a uniform microstructure increased with decreasing mean grain size, which complied with the Hall–Petch relationship. [ABSTRACT FROM AUTHOR]

In general, spatial data are not unified in the same coordinate system. The combination of data from different sources is considered a problematic practice in land surveying and geographic information systems (GIS). Therefore, there is a need to apply one of the coordinate transformation methods, in which have two types of transformations: analytical and numerical. The Universal Transverse Mercator (UTM) projection is widely used for maps in the Kingdom of Saudi Arabia (KSA), along with two different data: The World Geodetic System 1984 (WGS84) and The National Geodetic Network (NGN). This makes the process of analytical transformation more complex. In this paper, a new numerical transformation technique using a second-degree polynomial is proposed. Both analytical and numerical (second-degree polynomial) transformation types were applied for a single group of study points. Coordinates obtained from both the methods were compared. Moreover, the proposed method was also verified against the conformity criterion. Results indicated that the proposed transformation technique is conformal and can be effectively used for KSA maps. [ABSTRACT FROM AUTHOR]

The axisymmetric problem on the stress-strain state of a long thick-walled circular cylinder made of shape memory alloy experiencing the direct thermoelastic martensite phase transition under the action of constant internal and external pressures and a constant axial force is solved. The problem of limit loads in such a process is also considered. [ABSTRACT FROM AUTHOR]

The lattice parameters of cubic diamond and rhombohedral graphite under the probable direct transformation synthesis conditions have been obtained by means of linear expansion coefficient and elastic constant. Based on the empirical electron theory in solid and molecules, the valence electron structures (VESs) of graphite and diamond, the covalent electron densities (CEDs), and the relative electron density differences (REDDs) of the diamond growth interfaces have been calculated. It has been found that the REEDs of graphite/diamond interfaces were awfully large and the CEDs were discontinuous at the first order approximation. Not any meaningful atomic state of graphite structure, which satisfied the bond length difference formula, existed on the detonation synthetic conditions. Accordingly, it was considered that the direct transformation from graphite to diamond could not come true from the perspective of VES. In addition, the mechanism of synthesis diamond by explosive detonation was discussed based on the VESs of graphite and diamond. [ABSTRACT FROM AUTHOR]