induction stage
Recently Published Documents


TOTAL DOCUMENTS

45
(FIVE YEARS 16)

H-INDEX

4
(FIVE YEARS 2)

2022 ◽  
Vol 6 (1) ◽  
pp. 40
Author(s):  
Lei Wang ◽  
Xiao Lu ◽  
Lisheng Liu ◽  
Jie Xiao ◽  
Ge Zhang ◽  
...  

Currently, low heat Portland (LHP) cement is widely used in mass concrete structures. The magnesia expansion agent (MgO) can be adopted to reduce the shrinkage of conventional Portland cement-based materials, but very few studies can be found that investigate the influence of MgO on the properties of LHP cement-based materials. In this study, the influences of two types of MgO on the hydration, as well as the shrinkage behavior of LHP cement-based materials, were studied via pore structural and fractal analysis. The results indicate: (1) The addition of reactive MgO (with a reactivity of 50 s and shortened as M50 thereafter) not only extends the induction stage of LHP cement by about 1–2 h, but also slightly increases the hydration heat. In contrast, the addition of weak reactive MgO (with a reactivity of 300 s and shortened as M300 thereafter) could not prolong the induction stage of LHP cement. (2) The addition of 4 wt.%–8 wt.% MgO (by weight of binder) lowers the mechanical property of LHP concrete. Higher dosages of MgO and stronger reactivity lead to a larger reduction in mechanical properties at all of the hydration times studied. M300 favors the strength improvement of LHP concrete at later ages. (3) M50 effectively compensates the shrinkage of LHP concrete at a much earlier time than M300, whereas M300 compensates the long-term shrinkage more effectively than M50. Thus, M300 with an optimal dosage of 8 wt.% is suggested to be applied in mass LHP concrete structures. (4) The addition of M50 obviously refines the pore structures of LHP concrete at 7 days, whereas M300 starts to refine the pore structure at around 60 days. At 360 days, the concretes containing M300 exhibits much finer pore structures than those containing M50. (5) Fractal dimension is closely correlated with the pore structure of LHP concrete. Both pore structure and fractal dimension exhibit weak (or no) correlations with shrinkage of LHP concrete.


Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2271
Author(s):  
Juan H. Gonzalez ◽  
Joseph S. Taylor ◽  
Kelsey M. Reed ◽  
R. Clay Wright ◽  
Bastiaan O. R. Bargmann

Background: Regeneration of fertile plants from tissue culture is a critical bottleneck in the application of new plant breeding technologies. Ectopic overexpression of morphogenic factors is a promising workaround for this hurdle. Methods: Conditional overexpression of WUS and ARF5Δ was used to study the effect of timing the overexpression of these morphogenic factors during shoot regeneration from root explants in Arabidopsis. In addition, their effect on auxin-signaling activation was examined by visualization and cytometric quantification of the DR5:GFP auxin-signaling reporter in roots and protoplasts, respectively. Results: The induced expression of both WUS and ARF5Δ led to an activation of auxin signaling in roots. Activation of auxin signaling by WUS and ARF5Δ was further quantified by transient transformation of protoplasts. Ectopic overexpression of both WUS and ARF5Δ enhanced regeneration efficiency, but only during the shoot-induction stage of regeneration and not during the callus-induction stage. Conclusions: The overexpression of WUS and ARF5Δ both lead to activation of auxin signaling. Expression during the shoot-induction stage is critical for the enhancement of shoot regeneration by WUS and ARF5Δ.


2021 ◽  
Vol 12 ◽  
Author(s):  
Kamran Shah ◽  
Na An ◽  
Svetlana Kamanova ◽  
Lijuan Chen ◽  
Peng Jia ◽  
...  

In the external coincidence model, internal and external molecular signals, provided by the circadian clock and sunlight, respectively, are required to induce flowering. Salicylic acid (SA) applications during floral induction have multiple effects. In the current study, Malus × domestica plants were exposed to SA during the flower-induction stage to analyze the effect on various health markers and flowering. A total of 56 equal-sized Fuji/M9 trees that were about 7 years old were randomly divided into two groups. The first group (SA-treated) was sprayed with 4 mM SA solution, while the second group was sprayed with distilled water which served as control (CK). The SA applications increased various leaf pigments. Abiotic stress markers were increased in CK during the flower-induction stage. In the SA-treated group, non-enzymatic antioxidants increased, whereas in the control group, enzymatic antioxidants increased during the flower-induction stage. Histo-morphometric properties of leaves were significantly improved in the SA-treated group. The relative expression of the mRNA levels of MdMED80, −81, −3, and −41 were significantly increased in SA-treated leaves, leading to an early and increased flowering phenotype. Thus, SA increased leaf expansion and health-related marker levels, which lead to early induction of flowering in M. domestica. Overall, our work established a role for leaf health assessments in the regulation of flowering in M. domestica.


2021 ◽  
Vol 39 (2) ◽  
Author(s):  
Tannia Navarrete-Correa ◽  
Flery Fonseca-Salamanca ◽  
R. Mauricio Barría

Objective. This work sought to determine the perception of behaviors of humanized nursing care and its relation with sociodemographic and clinical variables in patients hospitalized in a Hemato-Oncology Department. Methods. Analytic cross-sectional study conducted with 51 patients hospitalized in the Hemato-Oncology Unit at Hospital Base Valdivia, Chile. A survey containing sociodemographic and clinical information was applied together with the questionnaire on Perception of Behaviors of Humanized Nursing Care 3rd version” -PBHNC 3v (32 items distributed in the categories: Qualities of nursing work, Openness to nurse-patient communication, and Willingness to care). Results. Of the participants, 51% were women, with mean age of 46.5±16.6 years; 54.9% were diagnosed with Lymphoma and 78.4% were in the treatment induction stage. In 30 of the 32 items of the instrument, > 90% of the participants evaluated compliance with the behavior of caring at level of “always”. By categories, it was observed that for “Willingness to care” there was significantly lower score among patients from 18 to 49 years of age (p=0.0455). For the category “Openness to nurse-patient communication” lower median score existed in patients with Myeloma (p=0.0043) and in patients in the Remission-Consolidation stage (p=0.0084). Days of hospitalization were associated significantly with the category “Willingness to care”, being lower with 16 days and more (p=0.0242). Conclusion. High frequency was observed of humanized-care behaviors and small differences in their assessment that were associated with demographic factors like age, and clinical factors, like diagnosis, treatment stage, and days of hospitalization. 


Author(s):  
Juan Francisco Aguirre-Medina ◽  
Ana Laura Gálvez-López ◽  
Juan Francisco Aguirre-Cadena

Objective: To evaluate various explants and growth regulators in order to improve invitro propagation of Stevia rebaudiana through organogenesis.Design/Methodology/Approach: Explants and growth regulators in two differentconcentrations were evaluated. The explants were nodal segment, axillary bud, andapical meristem; while the growth regulators were benzylaminopurine (BAP) at 1.125 mgL -1 and 3.0 mg L -1 , naphthaleneacetic acid (NAA) at 1.5 mg L -1 and 3.0 mg L -1 , andCIDEF-4 brassinosteroids (BRs) at 1.0 mg L -1 and 1.5 mg L -1 . In total 18 treatments withseven repetitions. Contamination, oxidation, and survival were recorded duringinduction; while leaf number, regrowth height, and root presence were recorded duringmultiplication.Results: At the induction stage there was a differential response between explantsaccording to their ontogenetic age; during multiplication, the morphological componentsshowed differences between concentrations of growth regulators and explants, withhigher effectiveness when adding BAP to apical meristems.Study Limitations/Implications: Both the origin and the age of explants can inducedifferential growth while interacting with growth regulators. Findings/Conclusions: Apical meristem explants showed better advantages for in vitroreproduction of S. rebaudiana since they present less contamination and higher survivalat the induction stage, even when exhibiting the highest oxidation among explants,which did not influence the decrease in their survival. At the multiplication stage withapical meristem, height, leaf number, and root presence were increased. Values werehigh when interacting with BAP.


2021 ◽  
Author(s):  
Merve Simsek ◽  
Busra Yazicilar ◽  
Fatma Boke ◽  
Hayrunisa Nadaroglu ◽  
Azize Alayli ◽  
...  

Abstract Nanoparticules plays an important role in plant adaptation to abiotic stress, especially in response to salt stress. In this study, two alfalfa lines (Erzurum, and Muş) were used as the material for the response NaCl to CuO, ZnO and CaO nanoparticules (NPs). CaO is evident to be higher effective than CuO, ZnO in callus induction from leaf explants. The antioxidant enzyme activities were also determined in the callus cultures. The maximum activity in MDA analysis was observed from callus treated of 50 mM NaCl with 0.8 ppm CuO NPs. The callus induction stage without salt treatments indicated a best result in 0.8 ppm CaO NPs for H2O2 value compared to the other NPs. The callus induction stage without salt treatments indicated a best result in 0.8 ppm CaO NPs for POD value compared to the other NPs for POD activity. The best response in protein rate was obtained from callus induction stage and callus formation stage after 50 mM treatment NaCl with 0.8 ppm CuO. LSCM analysis evident that the NPs could migitate the negative effects of NaCl stress by the elimination of stress severity in callus cells. SEM analysis was supported the results obtained by LSCM analysis. Our findings suggest that CuO, CaO and ZnO NPs can offer a simple and effective method to protect alfalfa callus from NaCl stress severity.


2020 ◽  
Vol 10 (3) ◽  
pp. 285-292
Author(s):  
Andriy G. Anastasov ◽  
Olekcii V. Ovcharenko ◽  
Dmitry O. Nazin ◽  
Bohdan A. Tomashkevych ◽  
Yegor V. Mikhaylichenko

Introduction. An MRI-scan in early childhood requires anesthesia to create complete immobility of the patient due to the high incidence of artifacts with an MRI duration of 40 to 60 minutes. The purpose of the work is to select the components of anesthetic support in children from one month to three years old with MRI. Materials and methods. The object of the study was 33 patients aged one month to three years with congenital and acquired brain pathology. Anesthetic management intravenous general anesthesia without mechanical ventilation. Anesthesia in 11 (33.3%) patients of group 1 midazolam 0.5% 0.3 mg/kg, in 12 (36.4%) patients of group 2 midazolam 0.5% at a dose of 0.3 mg/kg + ketamine 5% 1.5 mg/kg, and in 10 (30.3%) patients of group 3 midazolam 0.5% at a dose of 0.3 mg/kg + propofol 2 mg/kg. Results. Group 1 patients achieved a sedation level on the RASS scale of 2.2 0.1 points with preservation of sound and tactile sensitivity, spontaneous involuntary movements limbs in 72.7% of cases. Group 2 patients had a lack of motor activity, consciousness - an assessment on the RASS scale 4.6 0.4 points, BIS 59.4 1%, increased in blood pressure by 7.3%, and normal without depression of respiratory function. Group 3 patients required careful titration of each subsequent dose, constant monitoring of breathing and hemodynamics, and, if necessary, maintaining adequate ventilation during the induction stage. Conclusion. The most rational components for anesthesia support in young children during MRI scanning are midazolam solutions at a dose of 0.3 mg/kg and ketamine at 1.5/kg.


2020 ◽  
Author(s):  
Cheng Cheng Ruan ◽  
Zhe Chen ◽  
Fu Chu Hu ◽  
Xiang He Wang ◽  
Li Jun Guo ◽  
...  

AbstractThe B3 superfamily is a plant-specific family, which involves in growth and development process. By now, the identification of B3 superfamily in pineapple (Ananas comosus) has not reported. In this study, 57 B3 genes were identified and further phylogenetically classified into five subfamilies, all genes contained B3 domain. Chromosomal localization analysis revealed that 54 of 57 AcB3 genes were located on 21 chromosomes.Collinearity analysis indicated that the segmental duplication was the main event in the evolution of B3 gene superfamily and most of them were under purifying selection. Moreover, there were 7 and 39 pairs of orthologous B3s were identified between pineapple and Arabidopsis or rice, respectively, which indicated the closer genetic relationship between pineapple and rice. Most genes had cis-element of abscisic acid, ethylene, MeJA, light, and abiotic stress. qRT-PCR showed that the expression level of most AcB3 genes were up-regulated within 1 d after ethephon treatment and expressed high level in flower bud differentiation period in stem apex. This study provide a comprehensive understanding of AcB3s and a basis for future molecular studies of ethephon induced pineapple flowering.


2020 ◽  
Author(s):  
Jiangping Mao ◽  
Chundong Niu ◽  
Ke Li ◽  
Muhammad Mobeen Tahir ◽  
Mingyu Han ◽  
...  

Abstract Background Melatonin (MT) plays a key role in the plant growth and development, however, whether MT involved in apple adventitious root (AR) development is not entirely understood. In present study, we set up four MT-treated groups at different times according to the stages of AR development and one control group in Malus domestica (MP), endogenous hormones levels of MT, auxin (IAA), zeatin-riboside (ZR), gibberellins (GA1 + 3), abscisic acid (ABA) were analyzed in five groups, then the expression of MT signal, IAA synthesis, transport, and signal transduction, cell cycle, and root development related genes were measured by RT-qPCR, the function of MdWOX11 was analyzes by technology of apple transgenic. Results Advance of AR development by MT is depended on its promotion of stage of AR induction at 0–2 d in the apple rootstocks. MT-treated increased IAA levels, there were crosstalk between MT and IAA during inducing AR formation. Expression analysis exposed that the expression of MdWOX11 induced by MT-treatment, and positively regulated AR formation in apple. Furthermore, MdWOX11 over-expressed lines produced more ARs than ‘GL3’, phenotypic analysis indicated that MdWOX11 over-expressed lines were more sensitive to exogenous MT-treatment than ‘GL3’, it was also indicated that MdWOX11 regulated AR formation in response to MT in apple rootstock. Conclusions MT promotes AR formation mainly during AR induction stage by inducing IAA levels as well as by up-regulation of MdWOX11.


2020 ◽  
Author(s):  
Nasibova EM

Aim: Optimization of anesthetic benefits in one-day surgery by using propofol. Materials: The study included 58 patients operated on for inguinal and umbilical hernias, dropsy of testicular membranes, cryptorchidism, varicocele, hemangiomas of various localization, phimosis and paraphimosis. Depending on the age of the children, this group was divided into 3 subgroups: IA (n=12) age 0-3 years, IB (n=33)-4-7 years old and IC (n=13)-8-16 years old. This study was carried out in five stages. Results: Basically, in all age groups, the performance of the cardiovascular system remained at the level of the initial values, however, certain hemodynamic changes characterizing the effect of propofol were revealed. The characteristic imbalances of the main parameters of the volumetric blood flow indicate hemodynamic stress that occurred against the background of the action of propofol in all groups during the induction of anesthesia. All this clearly and objectively characterizes the vasodilating properties of propofol, as a factor that causes the most typical changes in central hemodynamics. Indices of external respiration after premedication at the induction stage tended to decrease and indicated moderate hypoventilation. At the traumatic stage of the study, an increase in BH was observed, which was associated with the appearance of pain. Thus, propofol induction proceeded with a hypodynamic type of blood circulation. At the most traumatic time of the operation, despite an increase in the dose of fentanyl, hemodynamic parameters were hyperdynamic type of blood circulation, associated with insufficient relief of the pain component. And an increase in the dose of fentanyl led to the development of hypoventilation with subsequent apnea, which required mechanical ventilation. Thus, analyzing the results obtained, it should be noted that anesthesia during 'small' surgical interventions with propofol and fentanyl is not an optimal method. Since at the most traumatic time of the operation, it is necessary to increase the dose of fentanyl, and this leads to hypoventilation with the subsequent development of apnea, which requires correction. Conclusion: Analyzing the results obtained, it should be noted that anesthesia during "small" surgical interventions with propofol and fentanyl is not an optimal method. Since at the most traumatic time of the operation, it is necessary to increase the dose of fentanyl, and this leads to hypoventilation with the subsequent development of apnea, which requires correction.


Sign in / Sign up

Export Citation Format

Share Document