Stem Structure Research Articles

HBO aftereffect on lipid peroxidation and enzyme antioxidants of the brain: prospective experiental study

OBJECTIVE. Study the effect of a single and multiple administration of hyperbaric oxygenation (HBO) in the therapeutic regime on the processes of lipid peroxidation (LPO) and enzyme of antioxidative defense in phylogenetically various structures of the brain in the period of the immediate and remote aftereffect of expositions.
 MATERIALS AND METHODS. Experiments were carried out on 87 nonlinear white male rats weighing 180-230 grams. Hyperbaric oxygenation was conducted by medical oxygen in the experimental pressure chamber in the “mild” mode (2 ata, 50 min isopression), 1 session per day in the morning. The study was carried out after 1, 5, 10 sessions, in 5 and 10 days after 1 session and in 5 days after 5 sessions of HBO. The content of malondialdehyde (MDA) was determined in the brain stem, cerebellum and large brain hemispheres. The state of an enzyme element of antioxidant defense was evaluated by superoxide dismutase (SOD) and catalase.
 RESULTS. It was found that exposure to oxygen under high pressure caused increased intensity of LPO processes in the brain that progresses from 1 to 5 sessions. While MDA changes in the brain stem were detected later than in the hemispheres and cerebellum. LPO intensification in the brain proceeded against the background of increased activity of SOD. After 10 sessions of HBO LPO intensity decreased that was confirmed by reduced MDA content and SOD activity in examined brain tissue. Catalase activity reduced in the stem after 5 sessions and increased in the cerebellum and hemispheres after 10 sessions of HBO. Aftereffect of 1 HBO session was characterized by persistent increase in MDA concentration in the brain regions, detected in 5 and 10 days after exposure and was accompanied by increased SOD activity against the background of reduced catalase activity. In 5 days after 5 sessions the increase in MDA content and SOD activation was observed only in the tissue of the cerebral hemispheres.
 DISCUSSION. The use of HBO in the mode 2 ata, 50 min stimulates reactions of free radical oxidation (FRO) in the brain. The dynamics of their development with continued exposure shows that there are enough resources of the brain antioxidant defense to compensate hyperoxic load, including 10-fold exposure and no depletion of the reserves of enzyme antioxidant element in the brain is observed. After a single exposure of hyperbaric oxygen FRO activation remains during 10 days that can be concluded from an increased level of MDA and an increased activity of SOD in all the brain regions against the background of reduced catalase activity of stem structures and cerebellum. Repeated 5-fold exposures have a shorter metabolic “footprint”: in 5 days LPO effect and SOD activation are less pronounced than in the period of 1 session aftereffect both in 5 and 10 days.
 CONCLUSION. The therapeutic “mild” mode of HBO (2 ata, 50 min, 1 session per day) causes FRO activation in the brain tissue of experimental animals. Its intensity is controlled by the activation of enzyme protection mechanisms that is enough to compensate FRO changes with this mode of hyperoxic load. After ending exposures more pronounced aftereffect of HBO in the brain regions is found after 1 session compared to 5 sessions.

Farklı habitatlarda yayılış gösteren Tamarix tetrandra (Tamaricaceae) türünün karşılaştırmalı yaprak ve gövde anatomisi

In this study, the leaf and stem structure of Tamarix tetrandra Pallas ex. Bieb. species, which are distributed in riparian and salt marshes, were examined in terms of anatomical and micromorphological aspects. Specimens of the species have been preserved in 70% alcohol for anatomical study. Herbarium specimens were used for micromorphological studies. The studies showed that there were differences in anatomy and micromorphology. It was found that the stomata were embedded in the epidermis in the samples distributed in the salt marsh. In addition, stem epidermal cell length, sclerenchyma cell diameter, sieve tube cell diameter, and pith cell diameter were found to be greater in riparian species. In the correlation analysis, a positive correlation was observed between leaf lower surface stomata width and upper epidermis cell width, and between stem sclerenchymatic cell diameter and upper epidermis cell width in species distributed in salt marshes. The studies did not find intensive salt accumulation in the stem and leaf structures of the species that spread in the salt marsh. Salt uptake is thought to be inhibited in these species.

Anatomical Changes in Seedling of Pisum Sativum Linn. Under The Nickel Stress

A research investigation was conducted to find out how Nickel's different stresses affected the morphological alterations in Pisum sativum. Pisum sativum has a complex stem structure. In the transactional view, the stem of Pisum sativum is usually more or less square-shaped. The root's transverse section has a form which is slightly rounded. The structural abnormalities of Pisum sativum treated with different concentrations of Nickel indicated its toxic effect on the anatomical structure of the root and stem. Pisum sativum treated with lower to higher doses of Nickel showed few specific effects on stem anatomy. Plants treated with nickel had many structural changes in their roots.

Metabolome and transcriptome analyses identify the underground rhizome growth through the regulation of rhizome apices in Panax ginseng

Panax ginseng C. A. Mey. is a well-known oriental medicine as a stimulant and dietary supplement. The ginseng rhizome, as one of the principal medicinal organs, plays an important role in aboveground organ growth and root development, although no studies on ginseng rhizome growth have been recorded. In this study, we identified that shoot apical meristem (SAM) was included in the rhizome bud, which could regulate the underground rhizome growth of ginseng. In microscopic examination, ginseng SAM included the central zone, peripheral zone, rib zone, and organizing center; secondary root structures were observed in ginseng main roots and lateral roots; primary root structures were observed in ginseng fibrous roots; rhizome had a stem structure with pith and discontinuous cambium. The metabolites in different underground ginseng organs were identified using ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS), with oleanane (OA)-type ginsenosides accumulating primarily in the rhizome buds. In addition, ginseng rhizome buds contained a low level of 3-indoleacetonitrile (IAN, one type of auxin), a high amount of abscisic acid (ABA), and a high level of jasmonoyl-isoleucine (JA-Ile, active form of jasmonic acid). ABA and JA-Ile could drastically limit the shooting rate of ginseng embryonic calli, however IAN boosted the rooting rate. Furthermore, the expression of genes involved in ginsenoside biosynthesis, phytohormone production, and shoot stem cell regulatory pathways were studied. This is the first study of SAM in medicinal herbs, and we believe that the results may offer new information about the development of ginseng underground rhizomes.

Validation of brain parenchyma sonography as a marker of neurodegeneration in multiple sclerosis

BackgroundMultiple sclerosis (MS) is widely known to cause brain atrophy due to neurodegeneration. Neuroimaging investigations revealed a direct link between brain atrophy detected by MRI and impairment. Transcranial sonography is a safe, feasible and cost-effective imaging technique. In this study, we aimed to validate B-mode transcranial sonography (TCS) as a marker of neurodegeneration in MS. This study is the first study directed to set cut-off point for brain parenchyma measurement in Egyptian population. An observational, case–control study, conducted on 125 subjects; divided into 2 groups: first group, 71 healthy volunteers and patients’ group (54 patients) with relapsing–remitting multiple sclerosis (RRMS). All studied subjects were assessed using B-mode TCS. Transcranial sonography findings were categorized into: first, assessment of brain atrophy parameters by measuring diameter (cm) of third ventricle and both frontal horns of lateral ventricles. Then, the echogenicity of thalamus and brainstem structures (substantia nigra (SN), red nucleus) planimetric surface area (cm2) were assessed along with their abnormal echogenicity (cm2), while brainstem raphe was assessed semi-quantitatively for its echogenicity (intact or interrupted).ResultsQuantitative measures of brain atrophy: in normal control group the third ventricle diameter mean was 0.2 cm (± 0.08), right and left frontal horn diameter were 0.3 cm (± 0.13) and 0.28 cm (± 0.1), respectively, brain atrophy parameters could differentiate between MS patients and normal control group as a statistically significant (p< 0.001) larger ventricular diameter was found in MS patients. On the other hand, assessment of brain stem structures and thalamus showed no statistical significance between MS patients and normal control except in surface area of both red nuclei.ConclusionsBrain parenchymal sonography may be used as a tool in assessment of neurodegeneration in MS patients.

Enhancing crop productivity and sustainability through disease identification in maize leaves: Exploiting a large dataset with an advanced vision transformer model

The timely identification of diseases in maize leaf offers several benefits such as increased crop productivity, reduced reliance on harmful chemicals, and improved production of healthy crops, resulting in enhanced economic returns. Computer-aided systems (CAD) play a crucial role in agriculture by enabling timely and efficient disease identification in plant leaves. Deep learning-based CAD systems facilitate accurate and rapid diagnosis of maize leaf diseases. In this research, we introduce an advanced vision transformer model that achieves exceptional accuracy and inference speed in detecting diseases in maize leaves. To begin with, we adapt the Multi-axis vision transformer (MaxViT) model to a 4-class maize dataset, creating a lightweight structure that offers improved accuracy and inference speed. Furthermore, we enhance the accuracy by replacing the conventional convolutional structure in the MaxViT architecture's Stem with a Squeeze-and-Excitation (SE) block. In addition, to boost accuracy further, we employ the Global Response Normalization (GRN)-based MLP from the ConvNexTv2 architecture instead of the MLP in the MaxViT architecture. Notably, we combine the PlantVillage, PlantDoc, and CD&S datasets from the literature, resulting in the creation of the most extensive dataset available. This dataset is then divided into three sets: training, validation, and testing, enabling the evaluation of the generalization abilities of the deep learning models. Our study goes beyond previous research by offering a comprehensive comparison of the performance of over 28 CNN models and more than 36 vision transformer models on the newly created dataset. By achieving a remarkable accuracy rate of 99.24% and a high inference speed, the proposed method outperforms all existing deep learning models in the literature. Therefore, it has been demonstrated that this advanced vision transformer model, based on MaxViT, is exceedingly effective for practical applications in agriculture.

“Why am I here?”: A phenomenological exploration of first‐generation college student experiences in STEM majors within a predominantly white institution

AbstractFirst‐generation college students (FGCSs) are a growing population in undergraduate education. Research on FGCS primarily focuses on the challenges and barriers they encounter in college. While important, this literature offers a limited view of FGCS as learners. Moreover, minimal literature has examined these students' lived experiences within sciences, technology, engineering, and mathematics (STEM). This study explores the learning experiences of FGCS (N = 17) in undergraduate STEM programs at a mid‐sized, private, predominantly white institution. Guided by the frameworks of intersectionality and social cognitive career theory, the researchers utilized a qualitative, phenomenological research methodology to hear the perspectives of FGCS to and to identify problematic higher educational structures in STEM. Findings point to an elitist stance underlying STEM programs based in general disciplinary norms that restricted FGCS access to STEM majors and careers across social, academic, and professional elements of the academic experience. FGCS who were multiply minoritized based upon race, gender, and social class experienced the compounding of marginalization, and academic success and persistence came at a personal cost. Students also reported relying predominantly on personal strengths and motivations to overcome elitism in STEM rather than on institutional supports. Findings also highlight the variation in the first‐generation experience and identify the unique barriers FGCS encounter within STEM fields. Implications for dismantling inequitable structures for higher education in STEM attending to the social, academic, and professional inclusion of FGCS.

Heat shock-inducible clonal analysis reveals the stepwise establishment of cell fate in the rice stem.

The stem, consisting of nodes and internodes, is the shoot axis, which supports aboveground organs and connects them to roots. In contrast to other organs, developmental processes of the stem remain elusive, especially those initiating nodes and internodes. By introducing an intron into the Cre recombinase gene, we established a heat shock-inducible clonal analysis system in a single binary vector and applied it to the stem in the flag leaf phytomer of rice (Oryza sativa). With detailed characterizations of stem structure and development, we show that cell fate acquisition for each domain of the stem occurs stepwise. Cell fate for a single phytomer was established in the shoot apical meristem (SAM) by one plastochron before leaf initiation. Cells destined for the foot (nonelongating domain at the stem base) also started emerging before leaf initiation. Cell fate acquisition for the node began just before leaf initiation at the flank of the SAM, separating cell lineages for leaves and stems. Subsequently, cell fates for the axillary bud were established in early leaf primordia. Finally, cells committed to the internode emerged from, at most, a few cell tiers of the 12- to 25-cell stage stem epidermis. Thus, internode cell fate is established last during stem development. This study provides the groundwork to unveil underlying molecular mechanisms in stem development and a valuable tool for clonal analysis, which can be applied to various species.

Morphoanatomical Responses and Stomatal Conductance in Shaded and Sun-Exposed Broussonetia papyrifera Seedlings

Investigating invasive species’ morphoanatomical characteristics, such as leaf area and thickness of vascular tissues and storage cells, can reveal information about their adaptive ability and competitive advantage. Thus, we analyzed the variation in leaf, stem, and root morphoanatomical structure and stomatal conductance between shaded and sun-exposed seedlings of Broussonetia papyrifera to provide insights into management strategies to control its invasive ability. The variations in leaf area (LA), Leaf Mass per Area (LMA), stomatal density, thickness of palisade and spongy mesophyll tissues, thickness of xylem parenchyma cells, diameter of all xylem vessels in stem and roots and stomatal conductance were analyzed between shaded and sun-exposed seedlings. Results revealed that the LA and LMA of B. papyrifera were significantly larger in the sun-exposed than in the shaded condition. Seedlings exposed to sunlight also had thicker palisade mesophyll and xylem parenchyma cells. The diameter of xylem vessels in roots was also significantly higher in sun-exposed seedlings. Contrarily, a reverse pattern was observed in the diameter of stem xylem vessels (i.e., shaded &gt; sun-exposed seedlings). Physiologically, a higher stomatal conductance was also observed in sun-exposed seedlings. In conclusion, we found significant variations in leaf, stem, and root morphoanatomy and stomatal conductance between shaded and sun-exposed seedlings of B. papyrifera. The findings of the present study may provide valuable implications for managing or controlling its invasibility in the introduced range. Keywords: freehand technique, invasive species, Moraceae, paper mulberry, stomatal conductance

Relationships of Psychological and EEG Parameters in Depressive Patients Recovered from COVID-19

In order to clarify the neurophysiological mechanisms of psychological deterioration after coronavirus infection in 54 young female patients with depression who had previously undergone COVID-19, the relationships of neurophysiological (EEG) and psychological (according to the SCL-90-R inventory) parameters have been analyzed. The index values of some scales of the SCL-90-R questionnaire, reflecting the severity of symptoms associated with a weakening of control of activity and with increased excitability in the emotional sphere, significant positive correlations were found with the spectral power values of the EEG frequency sub-bands, indicating a reduced functional state of the frontal cortex, as well as increased activation of stem and limbic structures of the brain. The structure of correlations between psychological parameters and EEG spectral parameters in depressive patients who underwent COVID-19 indicates that psychological discomfort that persists after the disease (long covid) is associated with a decrease in the functional state of the frontal areas of the cortex, as well as with the “disinhibition” of the stem and limbic structures of the brain, possibly due to the weakening of the descending inhibitory influences from the frontal cortex.

Anatomical adaptations in the stem of Discocactus catingicola (Cactaceae) to the highly threatened ironstone outcrops from southeastern Brazil

The geosystems known as “cangas” are composed of ferruginous concretions and are characterized by being subjected to elevated temperatures and by having highly acidic, shallow, unfertile soils. The extremely harsh environmental conditions therein limit the occupation of cangas to a restricted number of species, such as Discocactus catingicola. We aimed to analyze the stem anatomy of D. catingicola occurring on cangas in order to assess which structural traits provide the species with an adaptive advantage to these geosystems. Stem samples were subjected to protocols of cross-sectioning, epidermal dissociation and lugol histochemical detection, and were then analyzed under light microscopy. Stems have a uniseriate epidermis and a thick cuticle. Paracytic stomata occur at the same level of pavement cells. Conspicuous substomatal chambers extend through the entire hypodermis height. The two-layered, collenchymatous hypodermis has a high amount of calcium oxalate inclusions in the form of prismatic crystals. Stem structure is also composed of a water-storing chlorenchyma, a starch and water storage parenchyma, and wide-band tracheids. Our findings revealed the occurrence of xeromorphic adaptive characters in D. catingicola which provide the species with its adaptive success in ironstone outcrops. The description of these anatomical traits in D. catingicola make up a pioneer report, thus being of great importance for future research on ecological plant anatomy not only of Cactaceae species but also of other unrelated xerophytes. We expect our work will assist researchers in the fields of anatomy, taxonomy and systematics of Cactaceae. Future research investigating the anatomy of D. catingicola populations occurring on ecosystems other than the lateritic cangas should provide a helpful comparative basis for evaluating the species degree of phenotypic plasticity.

In Silico Selection and Validation of High-Affinity ssDNA Aptamers Targeting Paromomycin.

Glycans are promising for disease diagnosis since glycan biosynthesis is significantly affected by disease states, and glycosylation changes are probably more pronounced than protein expression during the transformation to the diseased condition. Glycan-specific aptamers can be developed for challenging applications such as cancer targeting; however, the high flexibility of glycosidic bonds and scarcity of studies on glycan-aptamer binding mechanisms increased the difficulty of screening. In this work, the model of interactions between glycans and ssDNA aptamers synthesized based on the sequence of rRNA genes was developed. Our simulation-based approach revealed that paromomycin as a representative example of glycans is preferred to bind base-restricted stem structures of aptamers because they are more critical in stabilizing the flexible structures of glycans. Combined experiments and simulations have identified two optimal mutant aptamers. Our work would provide a potential strategy that the glycan-binding rRNA genes could act as the initial aptamer pools to accelerate aptamer screening. In addition, this in silico workflow would be potentially applied in the more extensive in vitro development and application of RNA-templated ssDNA aptamers targeting glycans.

Molecular detection and genetic characteristics of a novel porcine circovirus (porcine circovirus 4) and porcine reproductive and respiratory syndrome virus in Shaanxi and Henan Provinces of China

Porcine circovirus 4 (PCV4) is a recently discovered circovirus that was first reported in 2019 in several pigs with severe clinical disease in Hunan province of China, and also identified in pigs infected with porcine reproductive and respiratory syndrome virus (PRRSV). To further investigate the epidemic profile and genetic characteristics of the two viruses, 150 clinical samples were collected from 9 swine farms in Shaanxi and Henan provinces of China, and a SYBR Green I-based duplex quantitative real-time polymerase chain reaction (qPCR) was developed for detecting PCV4 and PRRSV simultaneously. The results showed the limits of detection were 41.1 copies/μL and 81.5 copies/μL for PCV4 and PRRSV, respectively. The detection rates of PCV4 and PRRSV were 8.00% (12/150) and 12.00% (18/150) respectively, and a case of co-infection with PCV4 and PRRSV was found in the lung tissue of a suckling pig with respiratory symptom. Subsequently, the complete genomic sequences of five PCV4 strains were obtained, of which one PCV4 strain (SX-ZX) was from Shaanxi province, and these strains were 1770 nucleotides in length and had 97.7%−99.4% genomic identity with 59 PCV4 reference strains. The genome characteristic of the SX-ZX strain was evaluated from three aspects, a “stem-loop” structure, ORF1 and ORF2. As essential elements for the replication, the 17-bp iterative sequence was predicted as the stem structure, in which three non-tandem hexamers were found at downstream with H1/H2 (12-CGGCACACTTCGGCAC-27) as the minimal binding site. Three of the five PCV4 strains were clustered into PCV4b, which was composed of Suidae, fox, dairy cow, dog and raccoon dog. Phylogenetic analysis revealed that seven PRRSV strains from the present study were clustered into the PRRSV-2 genotype. Collectively, these data extend our understanding of the genome characteristic of PCV4 as well as the molecular epidemiology and the genetic profile of PCV4 and PRRSV.

An improved displacement adjustment method for overlarge deformation of valve at the cryogenic temperatures

Cryogenic valves are mostly designed at the room temperatures and served at the cryogenic temperatures. The wide temperature difference between design and service conditions causes the overlarge deformation of the valve stem structure, resulting in the cryogenic valve prone to leakage, stuck and other unsafety issues. In this study, an improved displacement adjustment (IDA) compensation method is proposed to solve the problem of size over-tolerance and shape deformation of the valve stem at the cryogenic temperatures. The shape of the valve stem is redesigned by combining IDA and the finite element method to meet its ideal service requirements under the cryogenic conditions. One of the features of the IDA method is to optimize the compensation direction by considering the angle change of normal vector on valve stem surface. Another is to improve the iteration efficiency by recognizing the compensation factor through the Lagrange interpolation algorithm. The simulation and experimental results show that the proposed compensation method can effectively reduce the size and shape deviation of the valve stem. Therefore, this study provides a new method to reduce the stem deviation at the cryogenic temperatures by the shape compensation, which has reference significance for the design of other low temperature components.

SRT: Improved transformer-based model for classification of 2D heartbeat images

Electrocardiography (ECG) is a crucial tool for diagnosing cardiovascular diseases. In particular, combining clinical ECG with computer technology for automatic ECG analysis can improve ECG discrimination accuracy. In this study, to tackle the existing problems of 2D classification models (CNN and Transformer) of ECG heartbeat images, we proposed a 2D deep learning classification network SRT comprising a CNN and Transformer-encoder modules to improve the model structure. Furthermore, to identify the global and local differences between different types of ECG heartbeats, we propose a novel attention module (SC-RGA module) to assist the multi-headed attention mechanism in improving the feature extraction of ECG images and the Dilated Stem structure to expand the receptive field at the input of the network. We also applied a series of strategies to deal with data imbalances in public ECG datasets. Finally, we evaluated the performance of SRT using the MIT-BIH arrhythmia database, with a classification accuracy of 0.957, a sensitivity of 0.881, and an average F1 index of 0.826. Comparative experiments demonstrate that the proposed model outperforms several advanced methods.

Tonic Eye-Opening Associated with the «Burst-Suppression» Pattern in Patients with Acute Anoxic Brain Injury (Case Series)

Massive anoxic brain injury caused by cardiac arrest leads to wakefulness suppression up to coma. The prediction of outcome is based on the analysis of the clinical features and the results of instrumental tests. One of the well-known signs of an unfavorable prognosis is involuntary motor activity, which is most commonly represented by myoclonus. In case of their cortical origin, they are accompanied by epileptiform activity in the electroencephalogram (EEG).Material and methods. We present a case series and literature review concerning a very rare fatal sign, non-rhythmic spontaneous eye opening accompanied by a «burst-suppression» pattern (BS) in the EEG. All patients suffered from transient acute hypotension or arrhythmia that required cardiopulmonary resuscitation (CPR) in three cases. A literature search found only 11 publications describing post-anoxic tonic eye-opening (PATEO).Results. The PATEO with BS was observed for less than a day followed by cessation of brain bioelectric activity in all patients. Only two patients exhibited isolated eye-opening and closing, while the rest had axial and limbs myoclonus just after CPR. In one case, eyelid opening was followed by a clonic movement of the head to the right, the EEG bursts were prolonged and had spike-like morphology. Three patients received antiepileptic and sedative therapy. All patients died in 3-43 days after the fatal cardiovascular event.Visual superposition of bursts in EEG and myogram of m. orbicularis oculi demonstrating identical morphology for EEG and myographic bursts was described for the first time. Our cases and literature review confirm that, regardless of the intensive treatment, patients with PATEO have fatal outcomes.Conclusion. The clinical and electrographic PATEO with BS phenomenon always indicates a lethal prognosis. The origin of PATEO is still under discussion. We suggest that it could be caused by disinhibition of subcortical and stem structures during extensive death of cerebral cortical neurons.

Mutation types and frequency in Nigella damascena L. in the М2 and M3 generation, using ethyl methanesulfonate, nitrosomethylurea and a new derivative of dimethylsulfate, DG-2

Aim. To identify mutations and evaluate the mutation frequency in Nigella damascena L. cultivars (cvs) Bereginya and Charivnytsya (M2 and M3 generation), following treatment of their seeds with ethyl methanesulfonate (EMS), nitrosomethylurea (NMU) and a new derivative of dimethyl sulfate, DG-2. Methods. Treated Nigella seeds of two cvs with the mutagens for 6 and 16 h and in concentrations of 0.01 and 0.5 % for EMS and NMU and 0.05 and 0.5 % for DG-2. Results. A wide range of mutations (59 types) was obtained, that was divided into six groups: five groups with changes in the morphological type and one group with changes in the physiological type. Among the detected mutations, there were both previously known mutations and those obtained in this culture for the first time. The high- est mutation frequency (30 %) affecting synthesis of chlorophyll and structure of stem, shoots and leaves and 20 % for physiological features, was registered for NMU at 16 h and 0.05 % in cv. Bereginya. However, this NMU concentra- tion appeared to be lethal for cv. Charivnytsya. Conclusions. The new mutagen DG-2 proved to be most effective for inducing mutations in the corolla petal color of nigella, namely 4.0 at a 0.5 % concentration of the mutagen and 16h exposure for cv. Bereginya and 4.0 % at the same concentration and exposure for cv. Charivnytsya. DG-2 caused a substantial number of mutations in all six mutation groups affecting morphological and physiological traits. The clas- sic mutagen EMS was also effective across the spectrum of mutation groups in our study; however, it caused mutations at a lower frequency. The maximum mutation frequency under influence of EMC at a concentration of 0.05 % and an exposure of 16 h in cv. Bereginya was 11.0 %, and in cv. Charivnytsya 8.0 %. For all three mutagens used, an increase in the concentration of the active substance and of exposure time led to an increase in the mutation frequency in N. damascena plants. We will select mutants with economically valuable traits, such as tall, lodging-resistant plants and early maturing ones, for further work on the development of new cultivars of N. damascena for industrial cultivation.

Multi-Scale Topology Optimization of Femoral Stem Structure Subject to Stress Shielding Reduce.

Hip replacement femoral implants are made of substantial materials that all have stiffness considerably higher than that of bone, which can cause significant bone resorption secondary to stress shielding and lead to severe complications. The topology optimization design method based on the uniform distribution of material micro-structure density can form a continuous mechanical transmission route, which can better solve the problem of reducing the stress shielding effect. A multi-scale parallel topology optimization method is proposed in this paper and a topological structure of type B femoral stem is derived. Using the traditional topology optimization method (Solid Isotropic Material with Penalization, SIMP), a topological structure of type A femoral stem is also derived. The sensitivity of the two kinds of femoral stems to the change of load direction is compared with the variation amplitude of the structural flexibility of the femoral stem. Furthermore, the finite element method is used to analyze the stress of type A and type B femoral stem under multiple conditions. Simulation and experimental results show that the average stress of type A and type B femoral stem on the femur are 14.80 MPa, 23.55 MPa, 16.94 MPa and 10.89 MPa, 20.92 MPa, 16.50 MPa, respectively. For type B femoral stem, the average error of strain is -1682με and the average relative error is 20.3% at the test points on the medial side and the mean error of strain is 1281με and the mean relative error is 19.5% at the test points on the outside.

Dizziness: efficient approach to treatment and prevention

The article deals with the diagnosis of dizziness as one of the most common reasons for contacting the primary care system. The term “vertigo” refers to the illusory sensation of the rotational movement of objects around the patient or the patient himself. Traditionally, the clinic distinguishes “systemic” and “non-systemic” dizziness. However, the use of these two terms “systemic” (rotational) and “non-systemic” (presyncope, imbalance caused by a violation of the neural mechanisms for maintaining balance and balance of the body and postural phobic) dizziness can make it difficult to diagnose the etiological factor due to the ambiguity of the term “non-systemic”. The most severe and painful for the patient is rotational dizziness. Most often, dizziness is caused by pathological changes in the peripheral part of the vestibular system: vestibular neuronitis, benign paroxysmal positional vertigo, Meniere’s disease. Treatment of patients with dizziness involves etiopathogenetic and symptomatic therapy. Important, from a practical point of view, is the relief of rotational dizziness itself, regardless of its etiology. A number of studies have shown the possibility of using the combined drug cinnarizine 20 mg + dimenhydrinate 40 mg in the treatment of peripheral and central vertigo. The effectiveness of therapy for dizziness with the use of a combined drug is due to the fact that one component (cinnarizine) acts mainly on peripheral structures (labyrinth), and the second (dimenhydrinate) – on central (vestibular nuclei and related centers of the brain stem) structures, providing a good vestibulolytic effect . The drug has minimal undesirable effects, which makes it possible to use it in patients of different age groups. In the article, the authors consider the effectiveness of a fixed combination of cinnarizine 20 mg and dimenhydrinate 40 mg for the treatment and prevention of rotational verti go (vertigo) of various etiologies with the analysis of clinical cases.

Evaluation of informativeness of mutation groups of Nigella damascena L. M2 generation

Purpose. To carry out a mathematical and statistical evaluation of the mutagenesis data of the M2 generation of Nigella damascena varieties ‘Berehynia’ and ‘Charivnytsia’ in order to identify relationships between groups of mutations and mathematical justification of their use in the process of further analysis and selection of hereditary changes of mutant plants. Methods. Seeds of the varieties ‘Berehynia’ and ‘Charivnytsia’ were treated with chemical mutagens. The mutations identified by visual observation of the plants at different stages of their growth and development were divided into eight groups. In each group of each treatment option, the frequency of mutations was calculated as a function of the type of mutagen, its concentration and exposure time. The mathematical and statistical evaluation of the results was carried out using the MS Excel analysis package and Spearman’s rank correlation. Results. The mutational difference in the M2 generation between eight groups of Nigella damascena varieties ‘Berehynia’ and ‘Charivnytsia’ under the influence of the mutagens ethyl methanesulfonate, nitrosomethylurea and the new chemical mutagen DG-2 (a complex of 3-N,N-dimethylamino sulfonane with dimethyl) was identified and evaluated. It was found that the correlation value of the mutagenic effects ranged from 0.437 to 0.752 with significance levels from 3.540 ´ 10–5 to 0.037. The following groups of mutations can be considered informative: stem, shoot and leaf structures; flower structure; colour of the corolla petals; structure of the capsule; physio­logical changes in the process of growth and development. Conclusions. The effect of the mutagens EMS, NMU in concentrations of 0.01 and 0.05% and DG-2 in concentrations of 0.5 and 0.05% was determined on Nigella damascena varieties ‘Berehynia’ and ‘Charivnytsia’ after exposure for 6 and 16 hours. Mutations in the structure of the stem, shoots and leaves, the colour of the petals of the corolla, the structure of the flower and capsule, and those causing a violation of chlorophyll synthesis should be considered informative.