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Background: Micro-propagation is the primary technique for the mass propagation of greenhouse orchids. However, various factors, including culture media and cultivation systems, influence the scaling-up and efficient commercialization of in vitro techniques. The utilization of liquid cultivation systems and bioreactors are relatively cost-effective and has attracted significant attention for mass production. In this study, we evaluated the effects of eight culture media, in both semi-solid and liquid forms, on the growth of in vitro mini-plantlets of Phalaenopsis orchids. We subsequently assessed the performance of four selected media: half-strength modified Murashige and Skoog (1/2 MMS), modified FAST (MFAST), and two simplified media (SM1 and SM2), across four types of cultivation systems, including semi-solid media in glass jars, liquid media in a permanent immersion system using Erlenmeyer flasks on a shaker (PIS), and a temporary immersion system (TIS) in two forms: FA-Bio bioreactor (TIS-FA-Bio) and RITA® bioreactor (TIS-RITA®). Results: The results indicated that the optimal culture medium for orchid growth depends on the cultivation system used. Among the eight evaluated semi-solid and liquid media, the highest plant growth was observed in the SM2 medium, attributed to the presence of additives (banana powder and activated charcoal), two types of sugar (with high carbon content), and small amounts of nickel and ascorbic acid. The high carbon content in the SM2 liquid medium, combined with the temporary immersion explants in a large volume of medium in the TIS-RITA®, resulted in the highest total carbohydrate content and enhanced plant growth. The maximum quantum efficiency of photosystem II (Fv/Fm) and the number of plantlets per liter in SM2 semi-solid medium were higher than those in the 1/2 MMS semi-solid medium (control), leading to a 61.6% reduction in production costs. Furthermore, the number of plantlets per liter in the TIS-FA-Bio containing SM2 (10.8 USD) was higher than in TIS-RITA® with 1/2 MMS (39.3 USD), resulting in a 72.5% decrease in production costs due to a lower volume of medium and the use of inexpensive equipment. Conclusions: We recommend the use of SM2 in TIS-FA-Bio and TIS-RITA® for economical and efficient mass propagation of Phalaenopsis orchid. [ABSTRACT FROM AUTHOR]

Abstract Background Micro-propagation is the primary technique for the mass propagation of greenhouse orchids. However, various factors, including culture media and cultivation systems, influence the scaling-up and efficient commercialization of in vitro techniques. The utilization of liquid cultivation systems and bioreactors are relatively cost-effective and has attracted significant attention for mass production. In this study, we evaluated the effects of eight culture media, in both semi-solid and liquid forms, on the growth of in vitro mini-plantlets of Phalaenopsis orchids. We subsequently assessed the performance of four selected media: half-strength modified Murashige and Skoog (1/2 MMS), modified FAST (MFAST), and two simplified media (SM1 and SM2), across four types of cultivation systems, including semi-solid media in glass jars, liquid media in a permanent immersion system using Erlenmeyer flasks on a shaker (PIS), and a temporary immersion system (TIS) in two forms: FA-Bio bioreactor (TIS-FA-Bio) and RITA® bioreactor (TIS-RITA®). Results The results indicated that the optimal culture medium for orchid growth depends on the cultivation system used. Among the eight evaluated semi-solid and liquid media, the highest plant growth was observed in the SM2 medium, attributed to the presence of additives (banana powder and activated charcoal), two types of sugar (with high carbon content), and small amounts of nickel and ascorbic acid. The high carbon content in the SM2 liquid medium, combined with the temporary immersion explants in a large volume of medium in the TIS-RITA®, resulted in the highest total carbohydrate content and enhanced plant growth. The maximum quantum efficiency of photosystem II (Fv/Fm) and the number of plantlets per liter in SM2 semi-solid medium were higher than those in the 1/2 MMS semi-solid medium (control), leading to a 61.6% reduction in production costs. Furthermore, the number of plantlets per liter in the TIS-FA-Bio containing SM2 (10.8 USD) was higher than in TIS-RITA® with 1/2 MMS (39.3 USD), resulting in a 72.5% decrease in production costs due to a lower volume of medium and the use of inexpensive equipment. Conclusions We recommend the use of SM2 in TIS-FA-Bio and TIS-RITA® for economical and efficient mass propagation of Phalaenopsis orchid.

The palm Euterpe precatoria holds great social, cultural, and environmental importance. The heart of palm and the fruit are the main products used for industrialization due to their energetic properties. Thus, the aim of this study was to establish a suspension cultivation protocol for the species using different explant sources. For this, eight lineages of E. precatoria embryogenic calluses were tested, with five in liquid medium Murashige and Skoog (MS) with 5 μM Picloram and three for comparison in semisolid medium MS with 20 μM Picloram and 5 μM 2iP. The growth curve was obtained by weighing the calli from 60 to 180 days of cultivation. The Gompertz model was applied, and growth kinetics were evaluated. At 100 days, the contents of total soluble sugars (TSSs) and total soluble proteins (TSPs) were determined. Principal components (PCA) were measured. According to the analysis of the data, the cultivation of E. precatoria lineages in liquid medium was successfully carried out, and the establishment was achieved. The model can be considered adequate since the R2 values found describe more than 90% of the growth kinetics of the lineages. In the liquid system, lineages L1 (from leaf explants and multiplied in semisolid medium—SM), L2 (from leaf explants and multiplied in SM), and L6 (from zygotic embryo explants and multiplied in liquid medium—LM) showed the shortest time to double the biomass accumulation. Multivariate analysis reveals a significant increase in masses in liquid cultures, represented by lineages L6 and L2. There was statistical difference in the amount of TSSs extracted; the highest TSS levels were observed in lineages cultivated in LM. The protein content found was very low, showing statistical differences among the lineages. In this work, the establishment and multiplication of embryogenic calli of E. precatoria are described for the first time, and they emerge as viable alternatives for the vegetative propagation of the species. [ABSTRACT FROM AUTHOR]

Blueberries are high-value fruits. The traditional method of propagation by cuttings cannot supply the modern market with large quantities of seedlings. The method of micropropagation of plants in vitro makes it possible to bring the production of blueberry seedlings to the highest level. Blueberries have not been sufficiently studied in in vitro culture, so the search for the simplest and most cost-effective methods of micropropagation remains relevant. The problem of accelerated micropropagation of blueberries can be solved using rocker-type bioreactors, which differ from other models in terms of simplicity of design and low cost. A study was carried out to evaluate the effectiveness of micropropagation of Vaccinium corymbosum 'Bluecrop' in rocker bioreactors. Two types of bioreactors were compared: the bioreactor of the Platform system and the TIS rocker bioreactor modified by the author. As a control, blueberries were grown on a semi-solid medium. The effectiveness of blueberry micropropagation was evaluated by the following indicators: multiplication coefficient, shoot length, and proportion of vitrified shoots. Experiments were conducted on WPM medium, with zeatin supplementation at a concentration of 1.0 mg/l, resulting in optimal results. It is shown that the rocker bioreactor is slightly inferior to the plantform bioreactor in micropropagation but outperforms the method of micropropagation on semisolid media. The rocker bioreactor can be fully utilized for production purposes. In order to reduce costs and increase technical reliability, the working principle of the mechanical drive of the author's model of a rocker-type bioreactor was changed. [ABSTRACT FROM AUTHOR]

Plant in vitro cultures can be an effective tool in obtaining desired specialized metabolites. The purpose of this study was to evaluate the effect of light-emitting diodes (LEDs) on phenolic compounds in Rhaponticum carthamoides shoots cultured in vitro. R. carthamoides is an endemic and medicinal plant at risk of extinction due to the massive harvesting of its roots and rhizomes from the natural environment. The shoots were cultured on an agar-solidified and liquid-agitated Murashige and Skoog's medium supplemented with 0.1 mg/L of indole-3-acetic acid (IAA) and 0.5 mg/L of 6-benzyladenine (BA). The effect of the medium and different treatments of LED lights (blue (BL), red (RL), white (WL), and a combination of red and blue (R:BL; 7:3)) on R. carthamoides shoot growth and its biosynthetic potential was observed. Medium type and the duration of LED light exposure did not affect the proliferation rate of shoots, but they altered the shoot morphology and specialized metabolite accumulation. The liquid medium and BL light were the most beneficial for the caffeoylquinic acid derivatives (CQAs) production, shoot growth, and biomass increment. The liquid medium and BL light enhanced the content of the sum of all identified CQAs (6 mg/g DW) about three-fold compared to WL light and control, fluorescent lamps. HPLC-UV analysis confirmed that chlorogenic acid (5-CQA) was the primary compound in shoot extracts regardless of the type of culture and the light conditions (1.19–3.25 mg/g DW), with the highest level under R:BL light. BL and RL lights were equally effective. The abundant component was also 3,5-di-O-caffeoylquinic acid, accompanied by 4,5-di-O-caffeoylquinic acid, a tentatively identified dicaffeoylquinic acid derivative, and a tricaffeoylquinic acid derivative 2, the contents of which depended on the LED light conditions. [ABSTRACT FROM AUTHOR]

Hydrothermal carbonization (HTC) of wetland plant could achieve the recovery of phosphorus (P) via the production of P-enriched hydrochar to alleviate the crisis of phosphate resources, while the migration and transformation of P should be determined. In this study, Canna indica was derived into hydrochar through HTC at different temperatures (200°C-260°C) and liquid mediums (H2O, CaCl2, and NaOH). The P forms were systematically characterized using P K-edge X-ray absorption near edge structure (XANES), 31P liquid nuclear magnetic resonance (NMR), and sequential extraction. The total P content in hydrochar was up to 23 mg g−1 with mainly inorganic P (> 97.8%), and the recovery rate was almost 100% during NaOH-mediated HTC. The P species, monoester-P and soluble orthophosphate (ortho-P), in biomass were transformed to more stable ortho-P in hydrochars, which was highly dependent on temperature and liquid medium. With increasing temperature, Al/Mg-P was gradually replaced by Ca/Fe-P. The CaCl2 solution facilitated the transformation of Ca(H2PO4)2 into CaHPO4 by elevating the Ca/P ratio. While for the NaOH-mediated HTC, the CaHPO4 and Ca(H2PO4)2 were transformed to hydroxyapatite (74.3%-81.5%), and the proportion of MgHPO4 elevated with increasing temperature. The diffusive gradients in thin films (DGT) results implied that the addition of hydrochar greatly elevated the soil available P content, which was further promoted by high temperature and NaOH medium. These results indicate that the species and availability of P in hydrochar could be adjusted through varying liquid medium and reaction temperature, which provide guidance for the target design of P-enriched hydrochar and P reclamation. Highlight: • P-enriched hydrochar was prepared from the wetland plant by the modified HTC. • Liquid medium and reaction temperature affected the speciation dynamics of P. • P was stabilized with high temperature, Ca2+ addition, and alkaline liquid medium. • Hydrochar addition greatly elevated the soil available P content via DGT analysis. [ABSTRACT FROM AUTHOR]

Hibiscus moscheutos L. 'Berry Awesome' is a complex hybrid of the new Proven Winners Summerific series of varieties with highly ornamental characteristics. Micropropagation of highly ornamental varieties is important for mass production of planting material for commercial purposes. The traditional methods for propagating Hibiscus varieties, such as cuttings or seed propagation, however, do not guarantee high rates of production of high-quality seedlings. To solve this problem, an attempt was made to develop protocols for micropropagation of Hibiscus moscheutos L. 'Berry Awesome' in vitro on agar and liquid medium using a bioreactor system, followed by ex vitro adaptation of the regenerants. The optimal method for sterilization of nodal explants as well as the optimal composition of the initiation medium for shoot proliferation and rooting were determined. For micropropagation on a liquid medium, a rocker-type bioreactor was used, and its advantages over micropropagation on an agar medium were demonstrated. The results showed that the best sterilization method for nodal segment explants was as follows: pretreatment by rinsing with running tap water, sterile water, and distilled water for 70 min and soaking for 5 min in a mixture of solutions of ethyl alcohol (96%), hydrogen peroxide (38%), and water in a ratio of 1:1:2. In this case, live and sterile explants accounted for 62.6%. The optimal initiation medium for axillary buds in nodal segments was the Murashige and Skoog (MS) medium supplemented with 0.1 mg L−1 N-(2-chloro-4-pyridinyl)-N'-phenylurea (CPPU), which resulted in 73.3% of axillary buds being induced. The optimal solid proliferation medium was MS medium supplemented with 0.1 mg L−1 CPPU with a proliferation coefficient of 5.8. In a liquid medium, the optimal concentration of CPPU was 0.05 mg L−1 with a proliferation coefficient of 9.2. The best medium for rooting/shoots with agar and in bioreactors was MS medium with the addition of 0.1 mg L−1 indole-3-butyric acid (IBA). The highest rooting rate was 99.0% in both types of media, and the survival rate of plantlets was 88.7% in solid media and 98.7% in the bioreactor. [ABSTRACT FROM AUTHOR]

Plant in vitro cultures can be an effective tool in obtaining desired specialized metabolites. The purpose of this study was to evaluate the effect of light-emitting diodes (LEDs) on phenolic compounds in Rhaponticum carthamoides shoots cultured in vitro. R. carthamoides is an endemic and medicinal plant at risk of extinction due to the massive harvesting of its roots and rhizomes from the natural environment. The shoots were cultured on an agar-solidified and liquid-agitated Murashige and Skoog’s medium supplemented with 0.1 mg/L of indole-3-acetic acid (IAA) and 0.5 mg/L of 6-benzyladenine (BA). The effect of the medium and different treatments of LED lights (blue (BL), red (RL), white (WL), and a combination of red and blue (R:BL; 7:3)) on R. carthamoides shoot growth and its biosynthetic potential was observed. Medium type and the duration of LED light exposure did not affect the proliferation rate of shoots, but they altered the shoot morphology and specialized metabolite accumulation. The liquid medium and BL light were the most beneficial for the caffeoylquinic acid derivatives (CQAs) production, shoot growth, and biomass increment. The liquid medium and BL light enhanced the content of the sum of all identified CQAs (6 mg/g DW) about three-fold compared to WL light and control, fluorescent lamps. HPLC-UV analysis confirmed that chlorogenic acid (5-CQA) was the primary compound in shoot extracts regardless of the type of culture and the light conditions (1.19–3.25 mg/g DW), with the highest level under R:BL light. BL and RL lights were equally effective. The abundant component was also 3,5-di-O-caffeoylquinic acid, accompanied by 4,5-di-O-caffeoylquinic acid, a tentatively identified dicaffeoylquinic acid derivative, and a tricaffeoylquinic acid derivative 2, the contents of which depended on the LED light conditions.

Context: The rationalization of acid rain formation steps is fundamental for mitigating its effects. It is believed the hydroxysulfinyl radical is an intermediate species for the production of atmospheric sulfuric acid. Two stable configurations HOSO and HSO2 have been reported for such a radical in the gas phase. This work aims at studying these isomers in the aqueous medium. The electrical and reactivity quantities — electronic chemical potential (μ ), chemical hardness (η ), and electrophilicity (ϵ ) — are here calculated and compared. Considering first solvation shells (15 H2O for HSO2 and 23 H2O for HOSO), an increase of 25% in the dipole moment of HSO2 was obtained, while the dipole moment of HOSO decreases in 11%. Both solvated isomers grow softer (η decreases) contrasted to the gas phase. Methods: HOSO and HSO2 are studied through a sequential Monte Carlo/quantum mechanics approach. Lennard–Jones plus the Coulomb potentials were used to represent intermolecular potential interaction in the frame of the DICE package. Molecular structure calculations were performed at CASPT2/aug - cc - pV(T + d)Z level of theory using the MOLPRO suite of programs. [ABSTRACT FROM AUTHOR]

The use of a liquid medium in near-dry electrical discharge machining (EDM) with a two-phase gas‒liquid medium endows it with desirable characteristics such as a stable discharge process and high material removal rate. However, the effect mechanism of the liquid medium in near-dry EDM is not well understood, which limits its development. In this present, a variant of the near-dry EDM technology, namely, mixed-gas atomization discharge ablation processing (MA-DAP) of titanium alloy, is used to reveal the effect mechanism of a liquid medium in the process of near-dry EDM. This technology uses a mixed gas containing oxygen and a liquid medium to form the dielectric medium, so as to obtain a higher effective material erosion ability than near-dry EDM. Through the combination of experimental and theoretical modeling and analysis, it can be concluded that liquid dielectric water has the functions of endothermic cooling, inducing an intermittent gas supply environment between electrodes, efficient etching product removal, improving oxygen utilization efficiency, controlling oxygen diffusion speed, and increasing the discharge gap between electrodes, which can significantly improve the inter-electrode discharge state and material removal rate. Compared with conventional EDM, the material removal rate associated with MA-DAP technology increases by 16 times, and the relative wear rate of the electrode is reduced by more than 93%. [ABSTRACT FROM AUTHOR]

The preparation and modulation of bare nano-diamonds (NDs) are of great significant for further investigation into their intrinsic structures, exploring more underlying properties, unlocking latent performances and exploiting more extensive applications. In this study, bare NDs have been successfully synthesized and modulated through 343 nm femtosecond laser ablation in liquids (LAL). When laser scanning point interval (LSPI) was reduced from 4 μm to 0.5 μm, the average size of NDs decreased from 4.1 nm to 3 nm. While it remained around 3.2 nm for NDs obtained at different energies. Notable, sp3-C within NDs accounted for above 71 % at laser energy of diamond damage threshold (118 mW), and then transformed into sp2-C as laser energy increased. NDs prepared in water and ethanol differed in terms of their size distribution, intrinsic structure, and surface state. NDs@ethanol sized 3.8 nm exhibited higher sp3/sp2 ratio and more complex surface states than NDs@water sized 3.3 nm. These findings not only can provide valuable guidance for precise regulation of NDs preparation, but also can offer diverse structural NDs for exploring their potential applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Hibiscus moscheutos L. ‘Berry Awesome’ is a complex hybrid of the new Proven Winners Summerific series of varieties with highly ornamental characteristics. Micropropagation of highly ornamental varieties is important for mass production of planting material for commercial purposes. The traditional methods for propagating Hibiscus varieties, such as cuttings or seed propagation, however, do not guarantee high rates of production of high-quality seedlings. To solve this problem, an attempt was made to develop protocols for micropropagation of Hibiscus moscheutos L. ‘Berry Awesome’ in vitro on agar and liquid medium using a bioreactor system, followed by ex vitro adaptation of the regenerants. The optimal method for sterilization of nodal explants as well as the optimal composition of the initiation medium for shoot proliferation and rooting were determined. For micropropagation on a liquid medium, a rocker-type bioreactor was used, and its advantages over micropropagation on an agar medium were demonstrated. The results showed that the best sterilization method for nodal segment explants was as follows: pretreatment by rinsing with running tap water, sterile water, and distilled water for 70 min and soaking for 5 min in a mixture of solutions of ethyl alcohol (96%), hydrogen peroxide (38%), and water in a ratio of 1:1:2. In this case, live and sterile explants accounted for 62.6%. The optimal initiation medium for axillary buds in nodal segments was the Murashige and Skoog (MS) medium supplemented with 0.1 mg L−1 N-(2-chloro-4-pyridinyl)-N’-phenylurea (CPPU), which resulted in 73.3% of axillary buds being induced. The optimal solid proliferation medium was MS medium supplemented with 0.1 mg L−1 CPPU with a proliferation coefficient of 5.8. In a liquid medium, the optimal concentration of CPPU was 0.05 mg L−1 with a proliferation coefficient of 9.2. The best medium for rooting/shoots with agar and in bioreactors was MS medium with the addition of 0.1 mg L−1 indole-3-butyric acid (IBA). The highest rooting rate was 99.0% in both types of media, and the survival rate of plantlets was 88.7% in solid media and 98.7% in the bioreactor.

Agarwood (Aquilaria malaccensis Lamk.) is a forest product commodity with high economic value, but its availability in nature is decreasing due to deforestation and overexploitation. The availability of high-quality seedlings is necessary to meet the demand and conserve the sources of agarwood plants. Therefore, this study investigates the interaction effect between media types and 1-Naphthaleneacetic acid (NAA) concentrations on agarwood shoot development. It also aims to determine the best medium type and NAA concentration to stimulate agarwood shoot development. This research had two stages, namely the shoot induction and development. The shoot induction stage was conducted experimentally, using a completely randomized design (CRD) on a factorial treatment pattern of 2 factors i.e., the types of media and NAA concentrations. The shoots produced from the induction stage were cultured on Murashige-Skoog (MS) media with the same media types but without any NAA addition. Furthermore, the variables observed in both stages were the development of agarwood shoots, and the parameters measured included the number of shoots, number of leaves and shoot lengths. The results showed that the development of agarwood shoots was controlled by the type of medium used. Liquid MS medium supported with filter paper bridge produced the highest average number of shoots with 4.93 and 5.87 shoots explants-1 and length at 3.25 and 3.64 cm explant-1 in the induction and development stage, respectively. These findings will facilitate mass propagation of agarwood shoots, and in turn the availability of agarwood plantlets supports its conservation and production.

Orchid mycorrhizal fungi (OMF) from the rhizoctonia aggregate are generally considered to be soil saprotrophs, but their ability to utilize various nutrient sources has been studied in a limited number of isolates cultivated predominantly in liquid media, although rhizoctonia typically grow on the surface of solid substrates. Nine isolates representing the key OMF families (Ceratobasidiaceae, Tulasnellaceae and Serendipitaceae), sampled in Southern France and the Czech Republic, were tested for their ability to utilize carbon (C), nitrogen (N) and phosphorus (P) sources in vitro in both liquid and solid media. The isolates showed significant inter- and intra-familiar variability in nutrient utilization, most notably in N sources. Isolates produced generally larger amounts of dry biomass on solid medium than in liquid one, but some isolates showed no or limited biomass production on solid medium with particular nutrient sources. The largest amount of biomass was produced by isolates from the family Ceratobasidiaceae on most sources in both medium types. The biomass production of Tulasnellaceae isolates was affected by their phylogenetic relatedness on all sources and medium types. The ability of isolates to utilize particular nutrients in a liquid medium but not a solid one should be considered when optimizing solid media for symbiotic orchid seed germination and in understanding of OMF functional traits under in situ conditions. [ABSTRACT FROM AUTHOR]

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Salix viminalis L. is a species with high capacity for micropropagation and acclimation and could therefore be used to evaluate emergent techniques in the field of plant propagation. The aims of this study were to propagate willow in liquid medium with a continuous immersion system, to explore the application of photoautotrophic conditions and to investigate the adaptation of willow plantlets to different soils that could be used as alternatives to commercial peat. For proliferation, we used 3% sucrose or sugar-free medium, and as substrates, we used commercial peat, a soil from an oak forest with high organic matter content and a crop soil with low organic matter content. The effect of sugar supplementation during proliferation and the soil characteristics during acclimation and growth were evaluated on the basis of aerial and root growth and the hydrolytic and dehydrogenase enzymatic activities of the soils. The results indicate that under photoautotrophic conditions, the supplementation of sucrose during micropropagation did not affect the subsequent growth of the plantlets. All plants acclimated without loss, but the type of soil influenced the height and vigor. Plants produced the highest shoots in peat, whereas the most root development occurred in crop soil. Soil enzyme activities were more influenced by the type of soil than by the presence of plants. [ABSTRACT FROM AUTHOR]

The aim of this research was to investigate the inhibitory effect of Bacillus subtilis P5-6 against Staphylococcus aureus on different states of standard medium with the presence of sodium chloride at 5% (v/v), to develop an effective protective culture in food. Halophile Bacillus subtilis P5-6 isolated from Plara (Thai traditional salt fermented fish) contained both the genes encoding subtilin (spaS) and subtilosin (sboA). Only subtilosin gene expression was detected along with housekeeping gene BA-rpoB when co-cultured with Staphylococcus aureus. With the spot on lawn assay, cell suspension from the P5-6 culture showed inhibitory effect against Staphyloccus aureus, while no inhibition was observed when cell free supernatant was used. In liquid co-culture, the inhibitory effect of P5-6 on Staphylococcus aureus was observed when its inoculum size (population density of 8 log CFU/ mL) was double that of S.aureus. In solid medium, Bacillus subtilis P5-6 could exert higher antagonistic action against this target pathogen. Bacillus subtilis P5-6 displayed an inhibitory effect even when its population was 2 log CFU/ mL lower than that of Staphylococcus aureus. Solid state cultivation with the presence of sodium chloride could enhance production and/or activity of bacteriocin of P5-6. The observation reflects an importance of the self-inhibitory effect as found in liquid and solid medium cultivation system. The data obtained could be fundamental importance in bacteriocin production development and application of protective culture from P5-6 to protect food against Staphyloccus aureus-one of the most common cause of foodborne disease.

A unique method was developed to significantly improve the strength of Bi(1−x)Sbx single crystals, the most effective thermoelectric (TE) materials in the temperature range from 100 to 200 K due to their plastic deformation by extrusion. After plastic deformation at room temperature under all-round hydrostatic compression in a liquid medium, n-type Bi–Sb polycrystalline solid solutions show a significant increase in mechanical strength compared to Bi–Sb single crystals in the temperature range from 300 to 80 K. The significantly higher strength of extruded alloys in comparison with Bi–Sb single crystals is associated with the development of numerous grains with a high boundary surface as well as structural defects, such as dislocations, that accumulate at grain boundaries. Significant stability of the structure of extruded samples is achieved due to the uniformity of crystal plastic deformation under all-round hydrostatic compression and the formation of the polycrystalline structure consisting of grains with the orientation of the main crystallographic directions close to the original single crystal. The strengthening of Bi–Sb single crystals after plastic deformation allows for the first time to create workable TE devices that cannot be created on the basis of single crystals that have excellent TE properties, but low strength.

Somatic embryogenesis is an efficient micro-propagation technique, which can lead to mass multiplication of tea with a tap root. Hence, the development of a viable somatic embryogenesis and multiplication protocol through liquid culture conditions is needed to increase the efficiency of the protocol. Cotyledon-derived somatic embryos, leaf and stem callus of TRI 5001 cultivar, were tested with different liquid MS media. A significantly higher cotyledon-derived somatic embryo multiplication rate was observed in MS +3 mg/L Thidiazuron (TDZ) medium. Callus proliferation and compact and embryonic callus formation were comparatively higher in MS + 1.1 mg/L TDZ, 1.86 mg/L NAA medium, and subsequent somatic embryo formation was observed in MS + 0.1 mg/L NAA,1 mg/L BAP and 0.2 mg/L GA3 medium on callus produced on leaf explants. Higher nodal callus proliferation and compact callus formation were recorded in MS+0.11 mg/L TDZ 0.1 mg/L IBA and higher embryonic callus was observed in MS+0.1 mg/L TDZ, 1.86 mg/L NAA media. Plant regeneration was resulted in MS+3 mg/LBAP 0.1 mg/L NAA medium. Identified treatment combinations can be used as a foundation to establish somatic embryogenesis protocol through different explants of tea. [ABSTRACT FROM AUTHOR]

Objective. To improve stool sample culture and isolation of anaerobic flora, including Clostridioides difficile in the routine microbiological laboratory practice at the children’s oncology hospital. Materials and Methods. A total of 517 stool samples collected from patients in children’s oncology hospital from 2013 to 2015 were studied. All samples were analyzed by ELISA for C. difficile toxins and by culture according to dedicated 5 schemes for isolation of anaerobic bacteria, including C. difficile. Statistical significance of differences in isolation rates between the studied groups (culture schemes) was assessed by Pearson test. Results. Culture in liver broth and covering with technical agar followed by culture on anaerobic agar yielded 100% isolation rate of toxigenic C. difficile strains. This culture scheme is also suitable for isolating concomitant anaerobic flora: non-toxigenic C. difficile strains, Clostridium perfringens, other Clostridia spp. and Bacteroides spp. Conclusions. Use of the liquid accumulation medium and covering with technical agar make it possible to isolate anaerobic flora from stool samples and increase an isolation rate of toxigenic C. difficile strains to 100% of ELISA-positive samples.

The aim of this study was to propagate axillary shoots of Cannabis sativa L. using liquid medium in temporary immersion bioreactors. The effect of immersion frequency (3 or 6 immersions per day), explant type (apical or basal sections), explant number (8, 10, and 16 explants), mineral medium (Murashige and Skoog half-strength nitrates, β -A and β -H, all supplemented with 2-μM metatopoline), sucrose supplementation (2, 0.5, and 0% sucrose), culture duration (4 and 6 weeks), and bioreactor type (RITA® and Plantform™) were investigated. As a result, we propose a protocol for the proliferation of cannabis apical segments in RITA® or Plantform™ bioreactors. The explants (8 per RITA® and 24 per Plantform™) are immersed for 1 min, 3 times per day in β -A medium supplemented with 2-μM metatopoline and 0.5% of sucrose and subcultured every 4 weeks. This is the first study using temporary immersion systems in C. sativa production, and our results provide new opportunities for the mass propagation of this species. [ABSTRACT FROM AUTHOR]

The NeuMoDx HPV assay is a novel fully automated, real-time PCR-based assay for the qualitative detection of high-risk human papillomavirus (HPV) DNA in cervical specimens. The assay specifically identifies HPV16 and HPV18 and concurrently detects 13 other high-risk HPV types at clinically relevant infection levels. Following the international guidelines, the clinical performance of the NeuMoDx HPV assay for cervical intraepithelial neoplasia grade 2 or worse (CIN2+) against the reference standard Hybrid Capture 2, as well as intra- and inter-laboratory reproducibility were assessed on PreservCyt samples. The clinical accuracy of the assay was additionally evaluated against the clinically validated Alinity m HR HPV and COBAS 4800 HPV Test on PreservCyt samples, and against the clinically validated HPV-Risk assay on SurePath samples. The NeuMoDx HPV assay performance for CIN2+ was non-inferior to the reference methods on both sample types (all p < 0.05), and showed excellent intra- and inter-laboratory reproducibility (95.7%; 95% CI: 93.9–97.3; kappa value 0.90 (95% CI: 0.86–0.94); and 94.5%; 95% CI: 92.6–96.2; kappa value 0.87 (95% CI: 0.82–0.92), respectively). In conclusion, the NeuMoDx HPV assay meets international guideline criteria for cross-sectional accuracy and reproducibility, and performs equally well on cervical screening specimens collected in two widely used collection media. The NeuMoDx HPV assay fulfils the requirements to be used for primary cervical screening. [ABSTRACT FROM AUTHOR]

A classification of the heat exchangers of capacitance apparatuses with rotary mixers for use in mixing liquid media is described. A critical survey of the most characteristic heat exchangers now available is performed. [ABSTRACT FROM AUTHOR]

In the work, the study and determination of the acoustic parameters of the movement of a cavitation bubble in a liquid medium according to discrete and continuous models was carried out. The research is based on the hypothesis that the determination of the effective parameters of the work process of acoustic processing is implemented by applying a transitional physical model from a discrete to a continuous type of processing of the technological environment. The obtained analytical dependences allow to calculate the amplitude of oscillations and the frequency of natural oscillations. With the help of the specified formulas, it is possible to determine the zones of amplification or attenuation of the amplitude of oscillations for different frequencies of oscillations. The proposed formula for determining the frequency of natural oscillations, which takes into account changes in the properties of the medium from homogeneous at the initial stage to the appearance of cavitation bubbles at the specified frequency of natural oscillations. Numerical values of intensity, pressure, amplitude of oscillations, velocity, acceleration, viscosity and maximum bubble radius are given. The obtained numerical values can be used in practical calculations of acoustic processing parameters of different nature and properties of technological environments. [ABSTRACT FROM AUTHOR]

The in vitro shoot proliferation of endemic Begonia pavonina in three culture conditions i.e semisolid medium (SM), liquid culture medium (LM) and in temporary immersion medium; RITA System (TIM) was analyzed in this study. To minimize contamination rates, seeds were surface sterilized and cultured on MS basal media. The clean raised shoots were then used as explants for inoculation onto the tested culture conditions. For this experiment, the explants were maintained in MS medium supplemented with 0.1mgL-1 BAP for shoot multiplication. After 4 weeks of incubation, higher regeneration rates were observed in TIM as compared to other medium conditions. The propagation rate in TIM was nearly doubled as compared to liquid as well as in solid medium. Shoot hyperhydration was also lowest in a TIM system. Overall, TIM has shown to produced higher shoot multiplications combined with healthy morphological characteristics of plantlets. Shoot cultures from the all cultures successfully rooted in vitro and acclimatized well in the greenhouse.

The aim of this study was to propagate axillary shoots of Cannabis sativa L. using liquid medium in temporary immersion bioreactors. The effect of immersion frequency (3 or 6 immersions per day), explant type (apical or basal sections), explant number (8, 10, and 16 explants), mineral medium (Murashige and Skoog half-strength nitrates, β-A and β-H, all supplemented with 2-μM metatopoline), sucrose supplementation (2, 0.5, and 0% sucrose), culture duration (4 and 6 weeks), and bioreactor type (RITA® and Plantform™) were investigated. As a result, we propose a protocol for the proliferation of cannabis apical segments in RITA® or Plantform™ bioreactors. The explants (8 per RITA® and 24 per Plantform™) are immersed for 1 min, 3 times per day in β-A medium supplemented with 2-μM metatopoline and 0.5% of sucrose and subcultured every 4 weeks. This is the first study using temporary immersion systems in C. sativa production, and our results provide new opportunities for the mass propagation of this species.

In this study, we propagated two old Galician plum varieties in liquid medium using a temporary immersion system with RITA© bioreactors. Environmental variables including culture system, light intensity, CO2 enrichment, immersion frequency and sucrose supplementation were evaluated in relation to in vitro proliferation, physiological status and ex vitro performance. Bioreactors were superior to jars for culturing shoots in photomixotrophic conditions, producing up to 2 times more shoot numbers and up to 1.7 times more shoot length (depending on the genotype) using shoot clusters. The number and quality of shoots were positively influenced by the sucrose concentration in the medium, plus by the light and gaseous environment. For individual apical sections the best response occurred with 3% sucrose, 150 µmol m−2 s−1 photosynthetic photon flux density and 2000 ppm CO2, averaging 2.5 shoots per explant, 26 mm shoot length and 240 mm2 leaf area, while with 50 µmol m−2 s−1 light and ambient CO2 (400 ppm) values decreased to 1.2 shoots per explant, 14 mm of shoot length and 160 mm2 of leaf area. Shoots cultured photoautotrophically (without sucrose) were successfully rooted and acclimated despite of showing limited growth, low photosynthetic pigments, carbohydrate, phenolic and antioxidant contents during the multiplication phase. [ABSTRACT FROM AUTHOR]

Orchid mycorrhizal fungi (OMF) from the rhizoctonia aggregate are generally considered to be soil saprotrophs, but their ability to utilize various nutrient sources has been studied in a limited number of isolates cultivated predominantly in liquid media, although rhizoctonia typically grow on the surface of solid substrates. Nine isolates representing the key OMF families (Ceratobasidiaceae, Tulasnellaceae and Serendipitaceae), sampled in Southern France and the Czech Republic, were tested for their ability to utilize carbon (C), nitrogen (N) and phosphorus (P) sources in vitro in both liquid and solid media. The isolates showed significant inter- and intra-familiar variability in nutrient utilization, most notably in N sources. Isolates produced generally larger amounts of dry biomass on solid medium than in liquid one, but some isolates showed no or limited biomass production on solid medium with particular nutrient sources. The largest amount of biomass was produced by isolates from the family Ceratobasidiaceae on most sources in both medium types. The biomass production of Tulasnellaceae isolates was affected by their phylogenetic relatedness on all sources and medium types. The ability of isolates to utilize particular nutrients in a liquid medium but not a solid one should be considered when optimizing solid media for symbiotic orchid seed germination and in understanding of OMF functional traits under in situ conditions.

Salix viminalis L. is a species with high capacity for micropropagation and acclimation and could therefore be used to evaluate emergent techniques in the field of plant propagation. The aims of this study were to propagate willow in liquid medium with a continuous immersion system, to explore the application of photoautotrophic conditions and to investigate the adaptation of willow plantlets to different soils that could be used as alternatives to commercial peat. For proliferation, we used 3% sucrose or sugar-free medium, and as substrates, we used commercial peat, a soil from an oak forest with high organic matter content and a crop soil with low organic matter content. The effect of sugar supplementation during proliferation and the soil characteristics during acclimation and growth were evaluated on the basis of aerial and root growth and the hydrolytic and dehydrogenase enzymatic activities of the soils. The results indicate that under photoautotrophic conditions, the supplementation of sucrose during micropropagation did not affect the subsequent growth of the plantlets. All plants acclimated without loss, but the type of soil influenced the height and vigor. Plants produced the highest shoots in peat, whereas the most root development occurred in crop soil. Soil enzyme activities were more influenced by the type of soil than by the presence of plants.

The study reports a low-cost micropropagation protocol for Nardostachys jatamansi , a high value, critically endangered Himalayan herb. Shoot-bud bearing rhizome segments of the plant were made to sprout and elongate on 0.8% agar-gelled Murashige and Skoog's medium containing 3% sucrose. The sprouted shoots were then multiplied on agar-gelled as well as liquid MS medium containing various concentrations and combinations of kinetin (Kn) and 1-phenyl-3- (1,2,3-thiadiazol-5-yl) urea (thidiazuron or TDZ). Maximum number of shoots developed per explant after 30 days on 100 ml agar gelled (6.7 shoots) and 30 ml liquid (6 shoots) MS medium containing 0.5 mg l−1 Kn and 0.75 mg l−1 TDZ. Although rooting of in vitro shoots was attempted on full as well as half-strength MS medium containing different auxins, rooting was achieved in 100% shoots (3.07 roots/ shoot) after 30 days on half-strength MS medium supplemented with 1.0 mg l−1 indole-3- acetic acid (IAA). Different potting mixtures were used to acclimatize the micropropagated plantlets under polyhouse condition, but a maximum of 83% survival was recorded in sand and sand plus soil. The genetic fidelity of the in vitro plantlets was also assessed using Start Codon Targeted Polymorphism (SCoT) and Directed Amplification of Minisatellite DNA (DAMD) markers, and a total of 8.03% polymorphism was recorded. Eventually, the cost of micropropagation was reduced by 6.4 times during shoot multiplication and further by half during rooting. The present micropropagation method developed for N. jatamansi can have potential applications in medicinal plant-based industry. [Display omitted] • A low-cost micropropagation method for critically endangered Himalayan medicinal herb. • Cost of in vitro shoot multiplication reduced by 6.4 times in liquid shoot multiplication medium. • In vitro raised plants showed 8.03% polymorphism as compared to mother plant in genetic variability analysis. [ABSTRACT FROM AUTHOR]

The formation of food liquid medium structures containing at least 70 % of disperse particles with high dispersiveness has been considered. The possible formation mechanisms of food liquid medium structure when slow (hydrodynamic) and quick (acoustic) processes create favorable conditions for cavitation have been studied. The possibility to control these processes for initiation of mechanical and kinetic reactions that change the structure of the medium has been demonstrated. The invert syrup has been selected as the study object. The change in the invert syrup structure before and after such cavitation treatment has been recorded with the use of metallographic microscope Nikon Eclipse MA100. The decrease in disperse phase sizes from 2–3 µm to 0.1–0.4 µm along with establishing the high uniformity of component distribution as compared to the syrup without cavitation process treatment has been detected.

The preparation of porous ceramics by freezing casting has received increasing attention in recent years because of the advantages of green economy, controllable pore structure and excellent material properties. Based on the brief introduction to the principle of freezing casting process, the pore forming mechanism and conditions of freezing casting process were elaborated. The effect of liquid medium and freezing conditions on pore structure of porous ceramics was discussed in details. The material system of porous ceramics prepared by freezing casting and the typical technological conditions were summarized. Finally, it was pointed out that the research directions of freeze casting in the future are the effective control of pore structure and the preparation of new functionalized porous ceramics.

The aim of the present study was to assess the transcription of Listeria monocytogenes key virulence genes, namely sigB, prfA, hly, plcA, plcB, inlA, inlB, inlC and inlJ during subsistence on the surface of tomato, cucumber and carrot stored at 4, 10 and 30 °C for 0, 0.5, 6 and 24 h. Gene relative transcription was assessed through reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The results obtained, indicated that the relative transcription of plcA, plcB and inlB was more affected during subsistence on cucumber surface whereas the relative transcription of sigB, prfA, hly, inlA and inlC was more affected on tomato surface. Subsistence of the pathogen on carrot surface had only marginal effect on the relative transcription of the virulence genes assessed in the present study. In the majority of the cases, the aforementioned effects were dependent on the storage temperature employed. [ABSTRACT FROM AUTHOR]

Date palm micropropagation is commonly performed on gelled media. However, it’s typically a labour-intensive system and consequently plantlets production cost is very high. Therefore, it is necessary to develop cost effective alternatives without compromising the quality of produced plant material. New technologies based on liquid media in bioreactors have been developed to reduce the handling time, while increasing the multiplication rates and plant quality. The present research focuses on the comparison between Temporary Immersion System (TIS) and gelled media (GM) culture systems of two Moroccan date palm varieties ‘Mejhool’ and ‘Boufeggous’. Obtained results indicated that shoot and root lengths as well as shoot fresh and dry weights were significantly (P < 0.05) higher in TIS compared to GM. Moreover, the vigour of obtained shoots was better in TIS compared to GM. Therefore, TIS-derived plantlets have shown an acclimatization rate of 95% while this rate for GM-derived plantlets was 82%. Hence, bioreactors, as a growing system based on TIS, can be a valid alternative to conventional systems for in vitro culture, resulting in a reduction of cost, shelving area requirements, labour and time for the mass propagation of date palm cultivars.

Tissue culture have been used for plant propagation generally, and the medium has been important role in its growth. Vegetative propagation on Phalaenopsis sp orchids can be through the protocorm like bodies (PLB). Medium of affect on propagation of PLB was carried out on medium type, kind of basal medium and concentrations ratio of naphtaleneacetic acid (NAA) and benzylamino purine (BAP). The experiment used Completely Randomized Factorial Design with 3 replications and continued with the Duncan Multiple Range Test (DMRT) if there were significant differences. The results showed that the best callus formed in a combination of solid medium type and Murashige & Skoog (MS) basal medium was 100%. The most number of PLB produced from a combination of liquid medium types and a concentration ratio of NAA 1 mgL-1 and BAP 5 mgL-1, the most number of plantlet produced from a combination of MS basal medium and the concentrations ratio of NAA 0.1 mgL-1 and BAP 0.1 mgL-1, the number of PLB germination and PLB with leaves were influenced by each single factor.

The NeuMoDx HPV assay is a novel fully automated, real-time PCR-based assay for the qualitative detection of high-risk human papillomavirus (HPV) DNA in cervical specimens. The assay specifically identifies HPV16 and HPV18 and concurrently detects 13 other high-risk HPV types at clinically relevant infection levels. Following the international guidelines, the clinical performance of the NeuMoDx HPV assay for cervical intraepithelial neoplasia grade 2 or worse (CIN2+) against the reference standard Hybrid Capture 2, as well as intra- and inter-laboratory reproducibility were assessed on PreservCyt samples. The clinical accuracy of the assay was additionally evaluated against the clinically validated Alinity m HR HPV and COBAS 4800 HPV Test on PreservCyt samples, and against the clinically validated HPV-Risk assay on SurePath samples. The NeuMoDx HPV assay performance for CIN2+ was non-inferior to the reference methods on both sample types (all p < 0.05), and showed excellent intra- and inter-laboratory reproducibility (95.7%; 95% CI: 93.9–97.3; kappa value 0.90 (95% CI: 0.86–0.94); and 94.5%; 95% CI: 92.6–96.2; kappa value 0.87 (95% CI: 0.82–0.92), respectively). In conclusion, the NeuMoDx HPV assay meets international guideline criteria for cross-sectional accuracy and reproducibility, and performs equally well on cervical screening specimens collected in two widely used collection media. The NeuMoDx HPV assay fulfils the requirements to be used for primary cervical screening.

In this study, we propagated two old Galician plum varieties in liquid medium using a temporary immersion system with RITA© bioreactors. Environmental variables including culture system, light intensity, CO2 enrichment, immersion frequency and sucrose supplementation were evaluated in relation to in vitro proliferation, physiological status and ex vitro performance. Bioreactors were superior to jars for culturing shoots in photomixotrophic conditions, producing up to 2 times more shoot numbers and up to 1.7 times more shoot length (depending on the genotype) using shoot clusters. The number and quality of shoots were positively influenced by the sucrose concentration in the medium, plus by the light and gaseous environment. For individual apical sections the best response occurred with 3% sucrose, 150 µmol m−2 s−1 photosynthetic photon flux density and 2000 ppm CO2, averaging 2.5 shoots per explant, 26 mm shoot length and 240 mm2 leaf area, while with 50 µmol m−2 s−1 light and ambient CO2 (400 ppm) values decreased to 1.2 shoots per explant, 14 mm of shoot length and 160 mm2 of leaf area. Shoots cultured photoautotrophically (without sucrose) were successfully rooted and acclimated despite of showing limited growth, low photosynthetic pigments, carbohydrate, phenolic and antioxidant contents during the multiplication phase.

Laser-induced plasma micromachining (LIPMM) can be used to fabricate high-quality microstructures of hard and brittle materials. The liquid medium of the LIPMM process plays a key role in inducing the plasma and cooling the materials, but the liquid medium is overheated which induces lots of bubbles to defocus the laser beam and reduce machining stability. In this paper, a comparative investigation on bubble behavior and its effect on the surface integrity of microchannels in three types of liquids and at different depths during LIPMM has been presented. Firstly, the formation mechanism of microbubbles was described. Secondly, a series of experiments were conducted to study the number and maximum diameter of the attached bubbles and the buoyancy movement of floating bubbles in the LIPMM of single-crystal silicon under deionized water, absolute ethyl alcohol, and 5.6 mol/L phosphoric acid solution with a liquid layer depth of 1–5 mm. It was revealed that the number and maximum diameter of attached bubbles in deionized water were the highest due to its high tension. Different from the continuous rising of bubbles at the tail of the microchannels in the other two liquids, microbubbles in 5.6 mol/L phosphoric acid solution with high viscosity rose intermittently, which formed a large area of bubble barrier to seriously affect the laser focus, resulting in a discontinuous microchannel with an unablated segment of 26.31 μm. When the depth of the liquid layer was 4 mm, absolute ethyl alcohol showed the advantages in narrow width (27.15 μm), large depth (16.5 μm), and uniform depth profile of the microchannel by LIPMM. This was because microbubbles in the anhydrous ethanol quickly and explosively spread towards the edge of the laser processing zone to reduce the bubble interference. This research contributes to a better understanding of the behavior and influence of bubbles in different liquid media and depths in LIPMM of single-crystal silicon.

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department 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.)

Date palm micropropagation is commonly performed on gelled media. However, it's typically a labourintensive system and consequently plantlets production cost is very high. Therefore, it is necessary to develop cost effective alternatives without compromising the quality of produced plant material. New technologies based on liquid media in bioreactors have been developed to reduce the handling time, while increasing the multiplication rates and plant quality. The present research focuses on the comparison between Temporary Immersion System (TIS) and gelled media (GM) culture systems of two Moroccan date palm varieties 'Mejhool' and 'Boufeggous'. Obtained results indicated that shoot and root lengths as well as shoot fresh and dry weights were significantly (P < 0.05) higher in TIS compared to GM. Moreover, the vigour of obtained shoots was better in TIS compared to GM. Therefore, TIS-derived plantlets have shown an acclimatization rate of 95% while this rate for GM-derived plantlets was 82%. Hence, bioreactors, as a growing system based on TIS, can be a valid alternative to conventional systems for in vitro culture, resulting in a reduction of cost, shelving area requirements, labour and time for the mass propagation of date palm cultivars. [ABSTRACT FROM AUTHOR]

Thin-layer membranes and membrane compositions find application in different indus- tries as independent design elements and as coatings. With the development of new technolo- gies, functional coatings are become increasingly widespread. During the process of exploita- tion design elements and coatings interact with the environment. For the competent design of structures with thin-layer membranes, it is necessary to know the influence of the liquid me- dium on the change in their mechanical properties. The results of experimental studies on the topic under consideration are presented

Introduction: The GF677(Prunusamygdalus×P. persica) is a peach rootstock tolerant to Fe deficiency. Nowadays, it is mainly propagated through micro propagation. Widening and undesirable growth of leaves as well as poor rooting are major problems during its in vitro culture. GF-677 is one of the most suitable rootstocks for almond and peach used in calcareous soils to overcome lime-induced chlorosis. Therefore, in vitro micro propagation is important for commercial purposes. Using liquid medium, it may be possible to reduce costs to a level lower than solid medium and liquid medium is better than solid medium in growth. Both the brand and concentration of agar also affect the chemical and physical characteristics of a culture medium. One of the main factors on micropropagation is hormone specially BAP. Furthermore, shoot branching depends on the initiation and activity of axillary meristems, which usually controlled by cytokinin. The rooting stage, the induction of roots on explants from in vitro culture is crucial part in any micropropagation process. The ability of plant tissue to form adventitious roots depends on interaction of many exogenous and endogenous factors, including hormone. Most reports of adventitious root induction of woody species have involved treatments with exogenous auxins such as IBA, NAA or IAA. Dimassi-Theriou (1995) for rooting of GF-677 compared different culture media and results on the rooting of these rootstocks depend on the type of medium culture. Materials and Methods: Axillary shoot of GF677 was cultured on both liquid and solid media. In proliferation step both liquid and solid media (MS, DKW and WPM) were used in primary stages of the experiment. Medium containing BAP 1mg.land-1 NAA 0.1mg.l-1. Under growth chamber conditions, light intensity was maintained at 2500-3000 lux with an 8-hour dark period. For rooting, 3-4 cm-long shoots from previous culture were transferred to 1/2 MS medium containing IBA (0, 0.5, 1 and 1/5mg.l-1) and 6 , 0 g l-1 agar. Darkness during the last week of the rooting phase has been shown to be necessary in stimulating rooting in some woody species. Note that the room temperature was maintained at 25°C during this experimental stage. The experiment was carried out based on factorial adopted completely randomized design with 5 replications per treatment. Explants shoot lengths, shoot numbers, root lengths and root numbers were recorded after 4 weeks which propagated plants via tissue culture were transferred to soil medium using 50% peat and 50% perlit mixture. Results and Discussion: Shoot proliferation: The observation indicates that there were significant differences between solid and liquid media. Best results were achieved for proliferation by liquid medium and among which MS obtained the highest frequency. The highest number of shoot was observed in MS medium and the lowest number of shoot was observed in WPM medium. Increasing mineral concentration resulted in increased multiplication, growth rate and total mineral uptake by GF677 explants. Root initiation of in vitro: Various concentrations of IBA showed significant differences. The maximum number of roots and root length were observed in the medium containing 0.5 mg.l-1 IBA. The best results were obtained for rooting in liquid 1/2 MS supplemented with 0.5 mg.l-1 IBA. The mean survival of the plants were transferred to liquid medium (75%) and mean survival of the plants were transferred from the solid culture medium (50%). Conclusion: In conclusion, a micropropagation system for GF677 has been worked out utilizing nodal explants. Our investigation showed that the liquid MS medium with 1 mg.lit-1 BAP was the best for proliferation of GF677 and micropropagated plants were rooted and established in soil successfully. WPM medium is higher in chloride level which has been reported to result in growth depression in plants due to inhibited nutrient uptake, transport and utilization of nutrients variation in multiplication and growth of explants can be explained on the basis of water potential and mineral availability to the explants in the liquid medium. Many investigators have reported that IBA has a better effect on promoting adventitious root formation in comparison to IAA. The best results were obtained for rooting in 1/2 MS supplemented with 0.5 mg. l/1 IBA.

Abstract The in vitro propagation technique via temporary immersion bioreactors is a tool that, through the culture in a liquid medium, allows an increase in the efficiency of seedling production. Several researches with the strawberry crop have shown greater efficiency of the system compared to the conventional process of micropropagation in solid medium. In this sense, the objective herein was to establish a protocol of multiplication and rooting of the ‘Pircinque’ strawberry, in temporary immersion bioreactors. Two distinct and independent studies were carried out, characterized by the multiplication and rooting stages of strawberry explants, newly introduced and registered in Brazil. Two culture media (MS and KNOP) were studied and, as a control treatment, the growth of the explants in solid culture medium was evaluated with the addition of 5 g L-1 of agar. Different immersion times of the culture medium were explored: five or eight times a day, for 15 minutes. The study was composed of the culture medium and immersion time factors, as well as the control (solid) treatment. It was verified that the use of temporary immersion bioreactors system is an efficient technique for the multiplication and rooting of explants of strawberry cv. Pircinque, when compared to the conventional method of micropropagation with the use of solid culture medium, making it possible to optimize the production of seedlings in biofactories. The MS liquid medium, in contact with explants of ‘Pircinque’ strawberry five times a day, increased the growth of the aerial part and the root system.

The aim of the present study was to assess the transcription of Listeria monocytogenes key virulence genes, namely sigB, prfA, hly, plcA, plcB, inlA, inlB, inlC and inlJ during subsistence on the surface of tomato, cucumber and carrot stored at 4, 10 and 30 °C for 0, 0.5, 6 and 24 h. Gene relative transcription was assessed through reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The results obtained, indicated that the relative transcription of plcA, plcB and inlB was more affected during subsistence on cucumber surface whereas the relative transcription of sigB, prfA, hly, inlA and inlC was more affected on tomato surface. Subsistence of the pathogen on carrot surface had only marginal effect on the relative transcription of the virulence genes assessed in the present study. In the majority of the cases, the aforementioned effects were dependent on the storage temperature employed.

A novel laser shock forming process called micro-laser shock hydraulic forming (MLSHF) was proposed to fabricate a micro-bowl with miniature concave at the apex of the bottom. Liquid water, used as a soft punch, can generate pressure waves under the action of laser shock to deform a 30-μm-thick copper foil. The influence of laser energy on morphology, forming accuracy, thickness distribution, and surface quality under MLSHF process was discussed through experimental means. Experimental results showed that the miniature concave was fabricated at 1050 mJ, and the whole micro-bowl was formed at 1550 mJ. With the increase of laser energy, the fittability improved and rebound became increasingly severe. Serious thinning occurred at the fillet of the miniature concave. Moreover, the die with great surface quality reduced the surface roughness of the workpiece surface that contacted with the die. A numerical finite element analysis (FEA) model was established by Hypermesh/LS-DANA. The FEA model was firstly verified through an experiment, and then it was used to investigate the deformation behavior including dynamic forming process and strain distribution. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office 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.)

Highlights • Advanced mathematical modeling for different types of piezoelectric micro cantilever. • Utilizing modified couple stress theory. • Advanced liquid modeling. • Predicting the piezoelectric non uniform micro cantilever vibration behavior in fluid. • Tapping and non-contact topography in liquid. Abstract The use of higher vibration modes and different geometries of the atomic force microscopy (AFM) piezoelectric micro cantilever (MC) is affected by the surface topography quality in a liquid medium. Therefore, utilizing an appropriate MC geometry and vibration mode is of a great importance. This paper analyzes the effect of different types of AFM MCs on the surface topography quality in the noncontact and tapping modes in a liquid medium. The modified couple stress theory (MCS) in a liquid based on the Timoshenko beam theory is used in order to enhance the accuracy of MC dynamic modeling. In addition, the differential quadrature (DQ) method has been used to discrete the equations. Identification of environmental forces helps to measure the accurate MC vibration amplitude. Investigating the effect of geometric and force parameters on the MC vibration behavior leads to understanding the system to design it properly in a liquid medium. Based on the advanced dynamic modeling, the best MC geometry for the specific surface roughness has been determined in the liquid for the surface topography. Also, due to oscillating the MC near the sample surface, the effect of interaction forces between the sample surface and the MC, including van der Waals, contact and squeeze forces is analyzed in a liquid medium in addition to the hydrodynamic forces. Furthermore, due to the reduction of the MC amplitude caused by the squeeze force; the MC is angled in proportion to the horizontal surface. [ABSTRACT FROM AUTHOR]