Influence Of Growth Conditions Research Articles

Unpacking the point of no return under drought in poplar: insight from stem diameter variation.

A specific, robust threshold for drought-induced tree mortality is needed to improve the prediction of forest dieback. Here, we tested the relevance of continuous measurements of stem diameter variations for identifying such a threshold, their relationship with hydraulic and cellular damage mechanisms, and the influence of growth conditions on these relationships. Poplar saplings were grown under well-watered, water-limited, or light-limited conditions and then submitted to a drought followed by rewatering. Stem diameter was continuously measured to investigate two parameters: the percentage loss of diameter (PLD) and the percentage of diameter recovery (DR) following rewatering. Water potentials, stomatal conductance, embolism, and electrolyte leakage were also measured, and light microscopy allowed investigating cell collapse induced by drought. The water release observed through loss of diameter occurred throughout the drought, regardless of growth conditions. Poplars did not recover from drought when PLD reached a threshold and this differed according to growth conditions but remained linked to cell resistance to damage and collapse. Our findings shed new light on the mechanisms of drought-induced tree mortality and indicate that PLD could be a relevant indicator of drought-induced tree mortality, regardless of the growth conditions.

Influence of growth conditions on an antioxidative system in two bell pepper genotypes differing in susceptibility to phytopathogen bacteria Xanthomonas euvesicatoria

Influence of growth conditions on an antioxidative system in two bell pepper genotypes differing in susceptibility to phytopathogen bacteria Xanthomonas euvesicatoria

Escherichia coli biofilm formation and control by phenolic compounds from Salvia officinalis L. extracts

Biofilm is recognized as one of the virulence factors of uropathogenic Escherichia coli . It offers bacteria significantly increased tolerance to antibiotics and makes difficulties in infection eradication. In this study, the biofilm formation ability of clinical isolates of uropathogenic E. coli as well as the antibiofilm activity of the common Garden sage, Salvia officinalis L. extracts were investigated in vitro . The influence of growth conditions (nutrient composition and incubation period) on biofilm formation of E. coli strains was evaluated using crystal violet staining procedure. The tested strains better formed biofilms after a longer incubation period (48 h). In addition, biofilm formation depended on nutrient medium composition. The eight strains were slime producers (Congo red agar assay). The water, ethanol, acetone and diethyl ether S. officinalis extracts were screened for their ability to inhibit the formation and metabolic activity of E. coli biofilms using crystal violet and resazurin assay, respectively. The water extract was not active, while ethanol, acetone and diethyl ether extract exhibited antibiofilm activity (MBIC= 2.5-10 mg/mL). The microscopic visualization of treated E. coli LM1 biofilm has shown morphological and density changes. In addition, the concentrations of phenolic compounds were determined spectrophotometrically. The highest content of total phenolics was found in acetone extract while the flavonoids in water extract.

Influence of growth conditions on productivity of Echinacea purpurea in the year of sowing

Despite the great success in the creation of chemical drugs, the popularity of herbal medicine is increasing. Medicinal plants, including Echinacea purpurea, occupy a special place among natural sources of raw materials. An efficient place for the cultivation is the Middle Volga region. Since Echinacea has been cultivated recently, it has specific properties of wild species that could seriously influence on the process of cultivation. It could be observed in seed germination and during a long period from sowing to seedlings, which leads to an increase in weediness. In this regard, the purpose of the current research is to develop technological methods for the cultivation of Echinacea purpurea in the year of sowing, providing the greatest realization of the potential in conditions of unstable moisture. According to the results of the research carried out in 2014 – 2017 on the chernozem meadow soil on the experimental plot of Penza State Agrarian University, it was found that during the winter sowing of the crop (October 20 ... 30), the highest germination rate of 57.6% was noted, the number of plants was 115 pcs/m2. At the early spring sowing carried out at the end of April, it decreased by 4.8%. As a result of competition between themselves and the weed component, the number of surviving plants by autumn decreased to 97.7...106.9 pcs/m2. The highest green mass yield of 10.2 t/ha was obtained on winter sowing with three manual weed removal and pre-emergence application of Lazurit SP herbicide (0.5 kg/ha) followed by the application of Miura (0.6 l/ha) in phase 2-4 weed leaves.

Effect of native point defects on the photocatalytic performance of ZnIn2S4

Understanding of materials at atomic scale is mandatory for improving their physical properties in the desired way. Here, first-principles calculations with the most accurate hybrid functional are performed to investigate one of the most attractive photocatalyst ZnIn2S4. The electronic structures of perfect and defective cubic-ZnIn2S4 are examined as a representative of other ZnIn2S4 polymorphs. The influence of growth conditions on the photocatalytic activity of ZnIn2S4 is elucidated by considering the formation energy of native point defects under different growth conditions. Our results reveal that undoped ZnIn2S4 is a native n-type material owning to the high pinned Fermi-level under all growth conditions. The source of electron carriers in undoped ZnIn2S4 is the InZn antisite defect and its photocatalytic performance is declined by the formation of dominant compensating Zn vacancy defect. The S-poor growth condition of undoped ZnIn2S4 is unveiled to provide the best photocatalytic performance due to the highest pinned Fermi-level.

Influence of growth conditions from metalorganic compounds on the preparation of n-CdTe epitaxial layers using isopropyl iodide

The dependence of iodine incorporation in CdTe layers on the deposition conditions during metalorganic vapor phase epitaxy is investigated. The growth of the layers was carried out from dimethylcadmium and diethyltellurium in the hydrogen flow in a vertical reactor with a hot wall condition at a total pressure of 20 kPa. The total iodine concentration was determined by secondary ion mass spectrometry, the electrically active concentration was determined from the Hall effect measurement. The iodine incorporation depends on the crystallographic orientation of the substrate (were studied (100), (310), (111)A, (111)B, (211)A and (211)B), the concentration of the doping precursor (flux range 5·10-8-3·10-6 mol/min), the mole ratio of organometallic compounds (DMCd/DETe = 0.25-4), growth temperature (335-390oC) and the walls of the reactor above the pedestal (hot wall zone 290-320oC). The total iodine concentration reached 5·1018 cm-3 and the activation efficiency was ~4%. After thermal annealing in cadmium vapor at 500oC the activation efficiency was ~100%. Keywords: epitaxial layers, metalorganic vapour phase epitaxy, CdTe, iodine doping, isopropyl iodide, thermal annealing.

Towards accurate and simple morphometric sex differentiation in Bonelli’s Eagle Aquila fasciata nestlings: Interpopulation variations and influence of growth conditions

Morphometric methods of sex differentiation may be cheap, simple, quick, and reliable alternatives to molecular approaches. However, there are still important uncertainties regarding the use of morphometric methods in birds, particularly regarding their applicability to different populations and environmental conditions. Between 2004 and 2019, we sampled 245 Bonelli´s Eagle Aquila fasciata nestlings, 197 from nests in Catalonia (northeastern Spain) and Andalusia (southeastern Spain) and 56 that were partially or totally raised in captivity. Our objective was to develop morphometry-based sexing methods for Bonelli’s Eagle nestlings that can be applied in situ to different subpopulations and growth conditions. We recorded up to nine measures related to nestling body mass, bill, tarsus, and claw length. Tail and wing length were used to control for the age of nestlings, and all individuals were sexed genetically. We found important morphometric differences between the two natural subpopulations. According to our discriminant analyses, body mass and claw length were the most discriminant variables, both in wild and captivity conditions. Differences between sexes were more prominent during the flight feathers’ growing period. Feeding ad libitum in captivity conditions led to larger nestlings and reduced between-sexes differences. We provide different models for sexing Bonelli’s Eagle nestlings that can be applied according to the studied geographic location, growth conditions (wild versus captive), and balance between accuracy and simplicity. Overall, our findings highlight that extrapolating sex discriminant functions to different subpopulations and growth conditions may be risky.

Morphological Changes of Silica Shells Deposited on Gold Nanorods: Implications for Nanoscale Photocatalysts

Gold nanorods (GNRs) support strong localized surface plasmon resonances that can be exploited to enhance the fluorescence or catalytic properties of adjacent molecules. Coating GNRs with silica is frequently used to functionalize their surfaces, but full encapsulation limits the ability to control the spatial distribution of molecules and their related reactivity. For example, locating molecules near the ends of GNRs would enable their strong longitudinal plasmon resonance to be exploited, but such selectivity is challenging. So far, studies of anisotropic coating have been limited and the mechanism of the adsorption onto GNRs remains unclear. Here, we systematically investigated the anisotropic coating of the ends of GNRs with silica and the influence of growth conditions on the formation of silica shells. Three types of nanostructures have been observed and their origins are described: fully encapsulated core-shell GNRs, GNRs with only one end coated with silica, and dumbbell-like GNRs (dGNRs) with both ends coated. The study was performed at around room temperature, where the solubility and micellization of the surfactant cetyltrimethylammonium bromide (CTAB) can be tuned to affect the morphology, stability and density of resulting silica shells. Optimized parameters, in combination with an appropriate GNR aspect ratio, are shown to significantly improve the growth yield of dGNRs, which become the dominant product. A protocol for a high yield synthesis of dGNRs was developed, with a maximum yield exceeding 90 %. This study advances our understanding of the growth mechanism of anisotropic coating of GNRs and sheds light on the optimization of site-selective coating processes. The development of anisotropic GNR-based nanostructures for fluorescence/scattering amplifiers will be important in applications such as metal-enhanced fluorescence, surface-enhanced Raman scattering or plasmon-enhanced catalysis.

The influence of growth conditions on MALDI-TOF MS spectra of winemaking yeast: implications for industry applications

Previous studies have shown MALDI-TOF MS to be a powerful tool in wine yeast identification and potential prediction of application. However, it is also established that substrate composition influences protein expression, but the degree to which this may affect MALDI-TOF spectra (and analytical results thereof) has not been fully explored. To further inform assay optimisation, the influence on MALDI-TOF spectra was determined using eight Saccharomyces strains of diverse origins cultivated on grape juices from Pinot Noir and Chardonnay varieties, synthetic grape juice, and laboratory-grade artificial culture media (YPD broth and agar). Our results demonstrated significant influences of culture media on strain MALDI-TOF spectra. Yeast culture on YPD agar is recommended for taxonomic studies, with YPD broth culture of S. cerevisiae offering improved intra-subspecific differentiation Furthermore, our data supported a correlation between MALDI spectra and the potential industrial application of individual yeast strains.

The synthesis of carbon microspheres film composed of nano‐onions and its application as flexible supercapacitors

AbstractFlexible electrodes with superior mechanical and electrochemical properties are essential for flexible supercapacitors. A convenient and scalable colloidal film‐assisted chemical vapor deposition (CF‐CVD) method is developed for the one‐step fabrication of the carbon microspheres films composed of carbon nano‐onions (CMS‐CNO films). The influence of growth conditions (such as growth temperature, time, and gas ratio) during CF‐CVD process on the carbon structures and the growth mechanism of the CMS‐CNO films have been investigated. By controlling the growth conditions, the controllable preparation of CMS‐CNO films is realized. Such binder‐free films can be used for the assembly of flexible supercapacitors, and unique architecture can achieve excellent performance. Benefitting from the composite of nano‐micro zero dimensional structures, the performance of the film in supercapacitors is remarkably improved. At the current density of 5 mA cm−2, the area‐specific capacity can be 903 mF cm−2. When the current density is increased to 500 mA cm−2, the area‐specific capacity can be increased to 729 mF cm−2. This simple and low‐cost preparation process and the superb electrochemical performance suggest great potential applications of CMS‐CNO films in flexible supercapacitors.

Challenges in the crystal growth of Li2FeSiO4

The high-pressure optical floating-zone method enables single crystal growth of the Pmnb high-temperature phase of Li2FeSiO4. The influence of growth conditions on crystal quality, phase homogeneity, and impurity formation in Li2FeSiO4 is studied. The use of different starting materials, i.e., either the P121/n1 or the Pmn21 polymorph, as well as optimization of various growth conditions is investigated. Several mm3-sized high-quality single crystals are obtained by the choice of the Pmn21 polymorph as the starting material. A general challenge of Li2FeSiO4 crystal growth is polymorph control during crystallization. While the temperature gradient at the solid-liquid interface seems to have significant impact on stabilizing the Pmnb high-temperature phase, growth velocity has no evident effect.

Assessment of optimal growth conditions for specific carotenoids production by Chlorella vulgaris

Exploration of regional microalgae for carotenoids production under optimized cultural conditions is a sustainable economic and technical perspective. This study details comprehensive research on the influence of growth conditions on microalgal carotenoids. Carotenoid triggering factors were optimized to identify suitable growth conditions to produce specific carotenoids by Chlorella vulgaris. Media optimization and cultivation conditions were the factors considered and the results revealed the optimum growth conditions for carotenoid production by C. vulgaris was pH 8, 35°C temperature, 0.04 M salinity and 160 µE\m²\sec light intensity. Among the nutrient sources, potassium nitrate and potassium phosphate were suitable for nitrogen and phosphorous supplements. The results indicated optimizing the culture conditions and nutrient sources help to attain desirable carotenoid production by C. vulgaris. Specific carotenoids were extracted from the algal extract and were identified by high-performance liquid chromatography in which lutein (8.8%) was present as major carotenoid followed by astaxanthin (4.6%) and ?-carotene (3.9%). This study revealed that that carotenoid production by C. vulgaris could be enhanced by manipulating culture conditions thereby attain desirable carotenoid production.

Direct Tellurization of Pt to Synthesize 2D PtTe2 for High-Performance Broadband Photodetectors and NIR Image Sensors.

Platinum telluride (PtTe2) has garnered significant research enthusiasm owing to its unique characteristics. However, large-scale synthesis of PtTe2 toward potential photoelectric and photovoltaic application has not been explored yet. Herein, we report direct tellurization of Pt nanofilms to synthesize large-area PtTe2 films and the influence of growth conditions on the morphology of PtTe2. Electrical analysis reveals that the as-grown PtTe2 films exhibit typical semimetallic behavior, which is in agreement with the results of first-principles density functional theory (DFT) simulation. Moreover, the combination of multilayered PtTe2 and Si results in the formation of a PtTe2/Si heterojunction, exhibiting an obvious rectifying effect. Moreover, the PtTe2-based photodetector displays a broadband photoresponse to incident radiation in the range of 200-1650 nm, with the maximum photoresponse at a wavelength of ∼980 nm. The R and D* of the PtTe2-based photodetector are found to be 0.406 A W-1 and 3.62 × 1012 Jones, respectively. In addition, the external quantum efficiency is as high as 32.1%. On the other hand, the response time of τrise and τfall is estimated to be 7.51 and 36.7 μs, respectively. Finally, an image sensor composed of a 8 × 8 PtTe2-based photodetector array was fabricated, which can record five near-infrared (NIR) images under 980 nm with a satisfying resolution. The result demonstrates that the as-prepared PtTe2 material will be useful for application in NIR optoelectronics.

Influence of growth conditions on content of monolignols in Phragmites australis’ leaves

Using a cytochemical method and laser confocal microscopy, a sensitivity of content and distribution of monolignols in the leaves of Phragmites australis, grown in different natural conditions, was established. The leaves at stage of vegetative growth of two ecotypes of Ph. australis, which grew in water and on land, were studied. We present results obtained by comparing the data on the leaves of Ph. australis of air-water and terrestrial plants growing in natural conditions (Kyiv, Ukraine). It was found that the decrease in soil moisture leads to an increase in ratio of syringyl monolignol to guaiacyl (S-G) and to an increase in total content of monolignols (S+G) in epidermis and tissues of vessel bundles of the terrestrial plants. It was assumed that changing the ratio of monolignols and changing their content in the epidermis of leaves of terrestrial reed plants is one of the mechanisms of plant adaptation to lower soil moisture, which reduces transpiration and maintains optimal water potential in leaves of Ph. australis growing on land. Based on the obtained experimental data, we believe that high content of syringyl monolignol, which gives high strength to leaves and stems of terrestrial reeds, can serve as a marker for commercial use of these plants in various sectors of economy.

Ultra-long high quality catalyst-free WO3 nanowires for fabricating high-performance visible photodetectors

This work presents a study on the controlled growth of WO3 nanowires via chemical vapor deposition without catalyst, and their potential applications in visible photodetectors. The influence of growth conditions on the morphology of WO3 nanowires is studied in order to understand the growth mechanism of WO3 nanowires, and ultra-long (60 , the longest one ever reported) WO3 nanowires with a spindle shape are achieved by optimizing the growth conditions. It was found that the length of WO3 nanowires increases from 15 to 60 with increasing the argon carrier gas flow rate from 30 sccm to 90 sccm, and then saturates with further increasing the argon carrier gas flow rate. However, the length of WO3 nanowires reduces from 60 to 19 with increasing the tube inner pressure from 2.5 Torr to 3.5 Torr. The photoconductor detectors based on WO3 single nanowires present excellent device performance with a responsivity as high as 19 A W−1 at a bias of 0.1 V, a detectivity as high as 1.06 × 1011 Jones, and a response (rising and decay) time as short as 8 ms under the illumination of a 404 nm laser. These results indicate the great potential of WO3 nanowires for applications in fabricating high performance visible photodetectors.

Electrodeposition of Fe–Ni alloy on Au(111) substrate: Metastable BCC growth via hydrogen evolution and interactions

The electrodeposition of Fe–Ni alloy is usually complicated by the effects of anomalous codeposition and hydrogen evolution. Although the influence of the deposition conditions on the alloy composition has been studied extensively, very few works considered the influence of growth conditions on the phase constitution. In this work, various electrodeposition conditions were investigated to grow Fe–Ni alloy films (<30 nm) with similar compositions in the Invar-to-equiatomic range on Au (111) substrate. Highly (110) oriented BCC phase Fe–Ni with a Ni fraction (ca. 40 at.% Ni) well beyond the equilibrium solubility limit (5 at.% Ni) was obtained with a significant alloy deposition partial current. An increase in the fraction of the BCC phase was found to be associated with a higher alloy deposition partial current, but not necessarily with an increase in the hydrogen evolution partial current. Motivated by the findings from this work, the formation of the metastable BCC phase is speculated to depend on the competing kinetics between the inclusion and desorption of hydrogen adatoms at the electrodeposited growth front.

Fed-Batch Decolourization of Mixture of Brilliant Green and Evans Blue by Bacteria Species Applied as Pure and Mixed Cultures: Influence of Growth Conditions

Synthetic dyes, generally resistant, toxic and carcinogenic presents a substantial risk to the environment and health of human. The present study was aimed to decolourize a dye mixture (Evans blue and brilliant green) by selected bacterial strains cultivated at different growth conditions (e.g. unmodified, correction of pH value and supplementation with nutrients). The bacterial strains used as pure and mixed cultures include facultative anaerobes Aeromonas hydrophila (Abs37), Citrobacter sp. (Cbs50) and obligatory aerobe Pseudomonas putida (Pzr3). The efficiency of removal of all successive doses of dye mixture (4–5 doses, total load 170–200 mg/l) was tested in static conditions in fed-batch bioreactors. The modification of bacteria growth conditions influenced on decolourization efficiency: most advantageous was pH value correction combined with nutrient supplementation then pH correction alone and nutrient supplementation (final removal results 95.6–100%, 92.9–100% and 89.1–97.2%, respectively). The mixed bacterial cultures removed the total load of dyes with higher efficiency than pure strains (final removal 95.2–100% and 84.0–98.2%, respectively). The best results were obtained for the mixture of facultative anaerobe Citrobacter sp. and obligatory aerobe Pseudomonas putida which removed the highest load of dye mixture (200 mg/l introduced at five doses) in the shortest time (288 h), while the others pure and mixed cultures needed 425–529 h for removal four doses of dye mixture (total load 170 mg/l). The zoo- and phytotoxicity decreased after these processes (from V class of toxicity (extremely toxic) even to II class (low toxicity)). The main mechanisms of decolourization was biotransformation/biodegradation, supported by sorption.

Systematic study of vertically aligned ZnO nanowire arrays synthesized on p-GaN substrate by hydrothermal method

This study presents a simple and effective way to synthesize well-aligned single-crystalline ZnO nanowires (NWs) by the hydrothermal method (HTM). The influence of growth conditions on the morphology of as-grown ZnO NWs is discussed from the chemical reaction equilibrium perspective. The height and diameter of the NWs demonstrated tunability through the optimization of the growth parameters. The ZnO NWs exhibited optimal alignment along the c-axis perpendicular to the substrate, as observed through scanning electron microscopy and X-ray diffraction. The nucleation and epitaxial growth mechanism of NWs on p-GaN has also been investigated. The conditions to obtain high-density and vertically aligned NWs were optimized as 0.03 mol l−1 concentration, 90 °C temperature and 3 h time. Photoluminescence measurements revealed a strong and narrow UV emission at 380 nm. The formation of a ZnO/p-GaN heterojunction through HTM provides promising optoelectronic device applications riding on the advantages of feasibility, cost-effectiveness and non-toxicity.

Synthesis of metal chloride films: Influence of growth conditions on crystallinity

This paper presents the first deposition of metal chlorides by RF magnetron sputtering. By integrating the sputter chamber with an Ar-filled glovebox, films of hygroscopic chlorides can be synthesized and studied. The structure, composition, and morphology of FeCl3 and FeCl2 films were investigated as a function of deposition rate. In FeCl3 films, the deposition rate has a large impact on the crystallinity of as-deposited films regardless of the substrate used. At high deposition rates, 24 Å/s, FeCl3 films are crystalline with a preferred orientation along the 003-plane, while at low deposition rates, 0.5 Å/s, no crystalline peaks are observed for FeCl3. In FeCl2, the highest deposition rate achieved in this study was 0.2 Å/s which yields films with no crystalline peaks; therefore, Raman spectroscopy was used to confirm the presence of FeCl2. The deposition of iron chlorides by RF magnetron sputtering opens the way for the study of thin film metal halides to understand their growth, magnetic and electronic properties, and understand ion transport through their layered structures.

Influence of growth conditions on the optical spectra of gamma irradiated BaF2 and CaF2 crystals

A comparative study of the gamma irradiated BaF2 and CaF2 crystals obtained under different growth conditions, using the Bridgman technique, is presented. A special attention was attributed to the influence of trace amount of three impurities: lead, ytterbium and oxygen ions, on the γ–rays induced color centers. The small amount of Pb ions comes from the different raw materials used. The oxygen content is due to the low vacuum level during the growth process. The crystals with Yb content were intentionally doped with a small amount of YbF3. The CaF2 crystal is more sensitive to a trace amount of lead ions than the BaF2 host. The oxygen, in addition of the lead ions in the BaF2 host, is more harmful than the trace amount of PbF2. The small amount of YbF3 is useful in eliminating the color centers in visible range. The induced color centers are stable in time. The lead ions contaminated BaF2 and CaF2 crystals are not good materials for applications in which the radiation induced absorption bands are undesirable.