Universitatea Ovidius Constanţa
  • Constanţa, Constanţa, Romania
Recent publications
Soil tillage or herbicide applications are commonly used in agriculture for weed control. These measures may also represent a disturbance for soil microbial communities and their functions. However, the generality of response patterns of microbial communities and functions to disturbance have rarely been studied at large geographical scales. We investigated how a soil disturbance gradient (low, intermediate, high), realized by either tillage or herbicide application, affects diversity and composition of soil bacterial and fungal communities as well as soil functions in vineyards across five European countries. Microbial alpha-diversity metrics responded to soil disturbance sporadically, but inconsistently across countries. Increasing soil disturbance changed soil microbial community composition at the European level. However, the effects of soil disturbance on the variation of microbial communities were smaller compared to the effects of location and soil covariates. Microbial respiration was consistently impaired by soil disturbance, while effects on decomposition of organic substrates were inconsistent and showed positive and negative responses depending on the respective country. Therefore, we conclude that it is difficult to extrapolate results from one locality to others because microbial communities and environmental conditions vary strongly over larger geographical scales.
ContextEvaluating herpetofauna presence and the species-specific and species richness patterns in response to agricultural landscape features is essential for understanding the herpetofauna decline in agricultural landscapes.Objectives This work aimed to explore how different categories, extent and heterogeneity of crops affect herpetofauna distribution and diversity patterns at different spatial resolutions: UTM 50 km2, UTM 10 km2 and GPS coordinates.Methods Using presence-only data from online repositories we documented the occurrence of European amphibians and reptiles in crops and quantified crop extent and heterogeneity in 50 and 10 km2 grid cells, and in the recorded presence locations. We used logistic regressions to test the effect of crop extent on species occurrence and calculated the proportion of species showing a significant response to each crop category. We analysed species richness patterns with generalized additive models against crop extent, crop heterogeneity and crop categories extracted at GPS locations, as fixed effects.ResultsWe recorded 71 amphibian and 143 reptile species at 50 and 10 km2 spatial resolutions, and 58 amphibian and 108 reptile species at GPS resolution. Our results showed that amphibian and reptile species presence and richness are influenced by crop category, extent and heterogeneity and that spatial patterns were scale dependent. Species richness of both amphibians and reptiles was generally negatively correlated with crop extent but was enhanced by crop heterogeneity.Conclusion Our results provide useful information for future risk assessment of herpetofauna and conservation efforts to restore or sustain herpetofauna biodiversity in agricultural systems across Europe. We stress that the scale of landscape management may lead to contrasting outcomes.
This paper deals with the two-dimensional deformation in fibre-reinforced composites with new modified couple stress thermoelastic theory (nMCST) due to concentrated inclined load. Lord Shulman heat conduction equation with hyperbolic two temperature (H2T) has been used to form the mathematical model. Fourier and Laplace transform are used for obtaining the physical quantities of the mathematical model. The expressions for displacement components, thermodynamic temperature, conductive temperature, axial stress, tangential stress and couple stress are obtained in the transformed domain. A mathematical inversion procedure has been used to obtain the inversion of the integral transforms using MATLAB software. The effects of hyperbolic and classical two temperature are shown realistically on the various physical quantities.
Cannabinoids, terpenophenolic chemicals found only in cannabis, are primarily responsible for cannabis pharmacologic effects; nearly 150 distinct cannabinoids have been identified thus far. Among these, the main psychoactive molecule, tetrahydrocannabinol (THC), and the non-psychoactive counterpart, cannabidiol (CBD) are distinguishable. In the past decade, a CBD-containing pharmaceutical preparation was approved by Food and Drug Administration (FDA) for the treatment of drug-resistant epileptic seizures in children, and research trials for a variety of additional medical conditions for which CBD has been suggested as a therapy are being conducted. Additionally, the number of “CBD-containing” dietary supplements, largely available online, is increasing rapidly. Consequently, the necessity for the development of qualitative and quantitative methodologies for the analysis of the bioactive components of Cannabis is rising because of the increase in the production of therapeutic cannabis products. One of the analytical methods with good potential in cannabinoids analysis is capillary electrophoresis (CE). It has advantages related to high separation efficiency, relatively short analysis time, and the small consumption of analytes and reagents which generates relatively lower operational costs than other methods. This review focuses on the use of CE techniques to examine biological matrices and plant materials for the presence of cannabinoids and other bioactive compounds found in cannabis. The advantages, drawbacks, and applicability of the various electromigration approaches are also assessed. The article provides an overview of the “state of the art” and the latest trends in CE-based methods for the determination of cannabinoids.
The use of renewable energy (RE) is considered one of the most important topics of discussion regarding sustainable consumption and environmental protection nowadays. More than ever, a new energy crisis is forming due to the effect of political and military conflicts that have already been in place for some time. Our research envisages using a sample of 1126 respondents for the validation of a theoretical model that highlights the complex relationship between specific variables, such as concern for the environment, knowledge about renewable energy, perceived utility regarding RE usage, ease of use regarding RE, attitude toward RE utilization and behavioral intentions to use RE. The results show that attitudes towards renewable energy consumption are strongly influenced by the other latent constructs with perceived utility, social influence and concern for the environment being among the most determining ones. Behavioral intentions and the actual consumption behavior for RE are more and more clearly expressed in terms of decisions regarding the type of renewable energy technology preferred by consumers, and correlations with variables such as the level of education and higher income are easily highlighted.
New green and sustainable sources were chosen to obtain chitosan, an important material, with many applications in different fields. The present study is focused on egg capsules of Rapana venosa waste as raw material for chitosan oligomers. As previous studies revealed that chitosan extraction from this material takes place with a low yield, the present research aimed to optimize this step. A 22 experimental plan, with three replicates in the center, was proposed to investigate the influence of NaOH concentration and temperature on the yield extraction. After a primary analysis of the experimental data, a favorable temperature value was selected (90 °C) at which the total dissolution of the egg capsules was obtained. Then, at this temperature, the experimental plan was extended exploring the influence of the NaOH concentration on three levels (5, 6, and 7%) and the extraction duration on two levels (60 and 85 min). Based on all experimental data, a neural model was obtained and validated. The neural model was used to maximize the yield, applying Genetic Algorithm (GA) implemented in Matlab®. The resulting optimal solution is: NaOH concentration 6.47%, temperature 90 °C, duration 120 min, with a yield value of 7.05%.
Background and Objectives: The present study assessed the fetal growth restriction and clinical parameters of both human immunodeficiency virus (HIV)-negative and HIV-positive newborns from HIV-infected mothers in two HIV-acquired immunodeficiency syndrome regional centers (RCs) in Constanta and Craiova, Romania, in order to evaluate the adverse birth-related outcomes. Materials and Methods: These represent a retrospective study conducted between 2008 and 2019, in which 408 pregnant HIV-positive women, 244 from Constanta RC and 164 from Craiova RC, were eligible to participate in the study. Consecutive singleton pregnancies delivered beyond 24 weeks of pregnancy were included. Growth restriction in newborns was defined as the birth weight (BW) being less than the third percentile, or three out of the following: BW < 10th percentile; head circumference (HC) < 10th percentile; birth length (BL) < 10th percentile; prenatal diagnosis of fetal growth restriction; and maternal pregnancy information. Of the 244 newborns delivered in Constanta, RC, 17 were HIV-positive, while in Craiova, RC, of the 164 newborns, 9 were HIV-positive. All HIV-positive women were on combined antiretroviral therapy (cART) during pregnancy, similar to all HIV-positive newborns who received ARTs for the first six weeks. We search for the influence of anthropometrical parameters (i.e., HC, BL, and BW), as well as clinical parameters (i.e., newborn sex and Apgar score) for both HIV-negative and HIV-positive newborns, along with the survival rate of HIV-positive newborns. Results: There were no differences in the sex of the newborns within either group, with more than 50% being boys. Similarly, the Apgar score did not show any statistically significant values between the two groups (i.e., p = 0.544 for HIV-positive newborns vs. p = 0.108 for HIV-negative newborns). Interestingly, our results showed that in Craiova, RC, there was a chance of 2.16 to find an HIV-negative newborn with an HC < 10th percentile and a 2.54 chance to find an HIV-negative newborn with a BL < 10th percentile compared to Constanta, RC, without any significant differences. On the contrary, Constanta, RC, represented a higher risk of death (i.e., 3.049 times, p = 0.0470) for HIV-positive newborns compared to Craiova, RC. Conclusions: Our results support the idea that follow-up of fetal growth restriction should be part of postnatal care in this high-risk population to improve adverse birth-related outcomes.
Dicrotic wave fiducial point can represent a useful key metric for vasomotor activity evaluation and its morphology during a complete cardiac cycle gives insight about hemodynamic activity, especially for changes in blood pressure values. As an important fiducial point, despite of human evaluation, its behavior is rarely interpreted by an automated algorithm. The last approach is suitable for individual monitoring, but a drawback from scalability point of view. This paper proposes an algorithm for dicrotic wave detection in various blood pressure signal morphologies, extracted from photoplethysmography waveforms. Four major classes with an easy nomenclature to be understand are defined, based on different signals morphologies. A total of high quality 400 periods where visual inspected and selected to build a reference database for algorithm performance testing. An overall performance of 95.25% is obtained, but this detection rate is pulled down especially by depicted classes where dicrotic wave is almost absent and affected by the artifacts. The tested dataset has discarded unrealistic waveform suffering from artifact effect. The main source of error is due to multiple weak inflection points during one cardiac cycle, comparable in morphology with the investigated fiducial points.
Knowing the personality and autonomy factors of bodybuilders is a necessity in order to improve sports training, which would lead to the development of mental skills specific to competitive bodybuilding. The purpose of the study was to identify perception differences in personality and autonomy factors for three age categories of competitive bodybuilders in order to optimize the sports training process. The secondary purpose of the study was to identify perception differences in the characteristics of personality and autonomy in relation to the increase in the sporting age category of the competitive bodybuilders. The research sample included 30 competitive bodybuilders aged between 18 and 53 years, of which 21 were male and 9 were female, who were divided into three groups according to the sporting age category: G1-junior (18-23 years old), 10 athletes (33.3%); G2-senior (24-35 years old for female and 24-40 years old for male), 12 athletes (40%); G3-masters (over 35 years old for female and 40 years old for male), 8 athletes (26.7%). In the precompetitive stage, three standardized questionnaires were applied to the study participants, namely, two personality questionnaires (CP5F and ZKPQ) and a personal autonomy questionnaire (PAQ), which provided us with useful information for understanding the psychological profile of bodybuilding athletes. The results of the study were statistically significant, with Cronbach's Alpha coefficient indicating high internal consistency of the three questionnaires for all three sporting age groups, with higher values than the selected reference threshold of 0.700. According to the results of our study, the following personality and autonomy factors recorded higher and higher scores in direct relation with the increase in sporting age: extraversion, agreeableness, conscientiousness, emotional stability, autonomy, impulsive sensation seeking, value autonomy, behavioral autonomy , and cognitive autonomy. The personality and autonomy factors of which the scores did not increase directly proportionally to the sporting age category were sociability, activity, aggression-hostility, neuroticism-anxiety, and emotional autonomy. Competitive bodybuilders perceive the factors of personality and autonomy differently in relation to particularities of age and sports experience , and knowledge of these changes can contribute to the improvement of the sports training process
Background: Nations marked by a Marxist-Leninist ideology have suffered greatly due to a culture of abuse emphasized by the absolute absence of psychology, thus contributing to a diminished ability in recognizing the consequences of traumatic experiences. Objective: To improve the assessment of the presence and severity of posttraumatic stress disorder (PTSD) in such a cultural context, our paper aimed at developing an alternative self-report measure for PTSD - the Post Traumatic Symptom Scale (PTSs), developed by clinicians with wide relevant expertise, based on the natural language people use to describe its subjective experience. This research used multiple samples consistent with the corresponding objectives. Mokken Scale Analysis and the Classical Test Theory were both employed. The proposed scale was tested against five competing PTSD models, whilst also investigating the symptoms' clusters in two different samples by using, to our knowledge, a network analysis approach for the first time. Method: The results indicated excellent psychometric properties regarding internal consistency and temporal reliability, as well as convergent and discriminant validity. The results of MSA showed that the scale fully conforms to the assumptions of the monotone homogeneity model, interpreted as positive evidence for its use in clinical purposes. The factor analyses pointed that the newer models outperformed the standard DSM-5 model, with bifactor models displaying better fit indexes than second-order models. Finally, a distinct pattern of symptom activation in the high-risk group (i.e. first-responders) was found, bringing support for symptoms overlapping between PTSD and affective disorders, thus reinforcing the idea of bridge symptoms which has significant clinical implications. Results: This study presents an alternative sound instrument for measuring PTSD symptomatology focused on how people naturally describe their subjective experiences. Theoretical and practical implications are discussed alongside limitations. Highlights: The construction of PTSs encompasses cultural trauma and one's subjective experience.PTSs was tested against the five major competing models of PTSD.Network analyses suggest different patterns in a student sample vs. a first-responders one, with the accent on the negative alterations in cognitions and mood (NACM) model.
Introduction: Post-stroke depression (PSD) has complex pathophysiology determined by various biological and psychological factors. Although it is a long-term complication of stroke, PSD is often underdiagnosed. Given the diagnostic role of quantitative electroencephalography (qEEG) in depression, it was investigated whether a possible marker of PSD could be identified by observing the evolution of the (Delta + Theta)/(Alpha + Beta) Ratio (DTABR), respectively the Delta/Alpha Ratio (DAR) values in post-stroke depressed patients (evaluated through the HADS-D subscale). Methods: The current paper analyzed the data of 57 patients initially selected from a randomized control trial (RCT) that assessed the role of N-Pep 12 in stroke rehabilitation. EEG recordings from the original trial database were analyzed using signal processing techniques, respecting the conditions (eyes open, eyes closed), and several cognitive tasks. Results: We observed two significant associations between the DTABR values and the HADS-D scores of post-stroke depressed patients for each of the two visits (V1 and V2) of the N-Pep 12 trial. We recorded the relationships in the Global (V1 = 30 to 120 days after stroke) and Frontal Extended (V2 = 90 days after stroke) regions during cognitive tasks that trained attention and working memory. For the second visit, the association between the analyzed variables was negative. Conclusions: As both our relationships were described during the cognitive condition, we can state that the neural networks involved in processing attention and working memory might go through a reorganization process one to four months after the stroke onset. After a period longer than six months, the process could localize itself at the level of frontal regions, highlighting a possible divergence between the local frontal dynamics and the subjective well-being of stroke survivors. QEEG parameters linked to stroke progression evolution (like DAR or DTABR) can facilitate the identification of the most common neuropsychiatric complication in stroke survivors.
Animal colouration has a significant ecological role in defence, reproduction, and thermoregulation. In the case of melanism, it is a complex topic. Besides potential disadvantages such as higher risk of predation, melanistic ectotherms may have certain physiological advantages such as more efficient thermoregulation in colder climates and thus, reduced basking time. The common grass snake ( Natrix natrix ) is a widespread species throughout Europe and Asia. It exhibits a wide range of colour polymorphisms, from olive to dark grey, even albinistic and melanistic. Between 2016 and 2021, we conducted fieldwork in the Danube Delta Biosphere Reserve (DDBR) with the aim to document the geographic range of melanistic grass snakes. We categorised the melanistic expressions of N. natrix individuals as melanotic, completely melanistic, and partially melanistic. Melanistic snakes were encountered in all six localities visited, suggesting that the occurrence of melanistic grass snakes in the DDBR is geographically widespread. We observed both juveniles (n=2) and adults (n=11) with melanism, suggesting that individuals are born melanistic. However, the proportion of melanistic individuals in the general population of N. natrix from the DDBR is unknown. Only at Histria locality we studied the proportion of melanism in the grass snake population and 6.3% of the snakes caught were melanistic. Body size comparisons are not statistically significant because of the low sample size. The N. natrix melanistic morph’s geographical distribution in the DDBR is most likely due to an interaction of climate and habitats, which offer a thermal advantage in the face of predation pressure.
The COVID-19 pandemic has substantially transformed the individuals’ lives, affecting various industries and accelerating digitalization in almost all activity fields. The paper presents the way in which the banking sector has adjusted the financial services features in order to help the community during the health crisis, shaping the main opportunities offered by the new COVID-19 context for the Romanian banking sector. In the same time, the paper aims to analyze the clients’ perceptions of the banks’ CSR actions during COVID-19 crisis, suggesting the supportive role of the banks and the increased solidarity through digitalization. The customers’ expectations were addressed in correlation with a SWOT analysis applied to the most representative credit institutions by total assets. The investigation was based on a semi-structured questionnaire focused on the assessment of the CSR efforts of the banks to overcome the COVID-19 pandemic, correlated with a SPSS analysis. According to the research findings, pandemic has redesigned the Romanian banking sector, being a primary starting point to rewrite the CSR strategies to improve the organizational resilience of banks. The main lines of investigation focused on how banks can cope with complex crisis by highlighting the features of the most resilient banks, expanding the use of digital banking and linking the banks’ CSR approach to clients’ demand for digital services after the outbreak of the COVID-19 crisis.
Background: The prevalence of chronic kidney disease (CKD) correlates with the prevalence of hypertension (HT). We studied the prevalence and predictors of CKD in a representative sample of the Romanian adult population. Methods: A sample of 1470 subjects were enrolled in the SEPHAR IV (Study for the Evaluation of Prevalence of Hypertension and Cardiovascular Risk) survey. All subjects were evaluated for blood pressure (BP) and extensive evaluations of target organ damage, blood, and urine samples were undertaken. Results: A total of 883 subjects were included in the statistical analysis. Those experiencing CKD with an eGFR < 60 mL/min/1.73 m2 were older at 71.94 ± 7.4 years (n = 19, 2.15%) compared with those without renal impairment at 50.3 ± 16.21 years (n = 864, 97.85%), p < 0.0001. The prevalence of CKD among hypertensives (379 from 883) was 4.49% (17/379), while 17 out of 19 subjects with CKD had HT (89.47%). After adjusting for age, sex, and diabetic status, only serum uric acid (SUR) > 6.9 mg/dL (OR: 6.61; 95% CI: 2.063, 10.83; p = 0.004) was an independent risk factor and a predictor of CKD. Conclusions: The prevalence of CKD in hypertensive Romanian adults was more than ten times higher than in the normotensive population. Levels of SUR > 6.9 mg/dL were predictors of CKD.
We report a particular case of a spontaneously occurring pregnancy in a long-term amenorrheic patient due to a prolactinoma with high serum prolactin (PRL) following the failure of dopamine agonist therapy (DA) for infertility. Initially, clinical, laboratory, and genital ultrasounds were normal, but the serum PRL was 10,074 μIU/mL (n.v.: 127–637 μIU/mL), the PEG fraction was 71% (laboratory cut-off > 60%), and luteinizing hormone (LH) was significantly lower. An MRI revealed a pituitary tumor of 12.8/10 mm with a subacute intratumoral hemorrhage. DA was initiated, and menstrual bleeding reappeared with a reduction in the tumor’s volume to 1.9/2.2 mm at 12 months. Two years later, the patient renounced DA and follow-ups. After another 2 years, she became spontaneously pregnant. Serum PRL was 18,325 μIU/mL, and an MRI revealed a microprolactinoma of 2.1/2 mm. The patient gave birth to a normal baby at term, and she breastfed for six months, after which she asked for ablactation, and DA was administered. This case highlights the possibility of the occurrence of a normal pregnancy during a long period of amenorrhea induced by a microprolactinoma with a high level of serum PRL, even if DA fails to correct infertility. There was no compulsory relationship between the tumoral volume’s evolution and the evolution of its lactophore activity. The hypogonadotrophic hypogonadism induced by high PRL was mainly manifested by low LH, and in this situation, normal levels of FSH and estradiol do not always induce follicle recruitment and development without abnormalities in the ovary ultrasound.
The paper presents the results of the studies performed to establish the effect of the mixtures between limonene and clotrimazole against microbial pathogens involved in dermatological diseases, such as Candida albicans, Staphyloccocus aureus, and Escherichia coli. Preliminary data obtained from the studies performed in microplates revealed a possible synergism between the mixture of clotrimazole and limonene for Staphylococcus aureus. Studies performed “in silico” with programs such as CLC Drug Discovery Workbench and MOLEGRO Virtual Docker, gave favorable scores for docking each compound on a specific binding site for each microorganism. The tests performed for validation, with the clotrimazole (0.1%) and different sources of limonene (1.9% citrus essential oils), showed a synergistic effect on Staphylococcus aureus in the case of the mixtures between clotrimazole and the essential oils of Citrus reticulata or Citrus paradisi. The studies performed on Staphylococcus aureus MRSA showed a synergistic effect between clotrimazole and the essential oils obtained from Citrus bergamia, Citrus aurantium, or Citrus paradisi. In the case of Pseudomonas aeruginosa, essential oils and clotrimazole used alone did not exhibit antimicrobial activities, but the mixtures between clotrimazole and the essential oils of Citrus bergamia or Citrus sinensis exhibited a synergistic antimicrobial effect.
The purpose of this article is that of exploring one of the most valuable sources from Iceland’s golden age of sagas, the Saga of the People of Laxárdalr through the lenses of historical as well as literary criticism in order to provide an account of the ways in which Norwegian kings or queens were portrayed. The research methodology includes primary and secondary source analysis and qualitative analysis, as well as the comparative method, as the results are compared with similar findings from secondary literature. The edition of Laxdæla Saga that was used in the analysis is Muriel A. C. Press’s translation from 1999 and the main secondary sources used include works such as those of Ármann Jakobsson and William Ian Miller. The main findings are that, like in many other similar sources, the Norwegian monarchy is represented either in an either extremely positively or extremely negatively fashion by the author of the saga.
The selection of the appropriate resident for a plastic surgery training program is a complex task based on variable factors. These factors include criteria which can be perceived as objective or subjective and which are related to a candidate’s personality, communication skills, work ethic, surgical skills, academic curriculum, extra-curricular activities, and demographic profile. The presented study is aimed at identifying the primary selection criteria which are being taken into consideration by plastic surgery trainers. A survey was distributed to 95 plastic surgeons who are employed in Belgium or the Netherlands and who are involved in resident selection and training. Respondents were asked to rate the importance of 31 parameters in terms of relevance for plastic surgery residency and to pick the five parameters that they take into consideration the most for resident selection. According to 42 respondents, honesty and professional reliability are the most appreciated factors, followed by responsibility, pro-active attitude, and communication skills. In general, subjective parameters were more influential than scientific accomplishments and exam results. As the trainer’s experience increased, a candidate’s artistic skills, family situation, and activities outside of the hospital gained more importance, while younger trainers prefer to search for efficiency, punctuality, and multi-tasking ability. In conclusion, favorable personality traits are key determinants in the selection of a medical graduate for plastic surgery training. The decision-makers’ experience affects the desired profile and influences the composition of the future resident team.
Necrosis and increased microvascular density in glioblastoma IDH-wild-type are the consequence of both hypoxia and cellular immaturity. Our study aimed to identify the main clinical-imaging and morphogenetic risk factors associated with tumor necrosis and microvascular in the prognosis of patient survival. We performed a retrospective study (10 years) in which we identified 39 cases. We used IDH1, Ki-67 and Nestin immunomarkers, as well as CDKN2A by FISH. The data were analyzed using SPSS Statistics. The clinical characterization identified only age over 50 years as a risk factor (HR = 3.127). The presence of the tumor residue, as well as the absence of any therapeutic element from the trimodal treatment, were predictive factors of mortality (HR = 1.024, respectively HR = 7.460). Cellular immaturity quantified by Nestin was associated with reduced overall survival (p = 0.007). Increased microvascular density was associated with an increased proliferative index (p = 0.009) as well as alterations of the CDKN2A gene (p < 0.001). CDKN2A deletions and cellular immaturity were associated with an increased percentage of necrosis (p < 0.001, respectively, p = 0.017). The main risk factors involved in the unfavorable prognosis are moderate and increased Nestin immunointensity, as well as the association of increased microvascular density with age over 50 years. Necrosis was not a risk factor.
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745 members
Larion Alin
  • Faculty of Physical Education and Sport
Liliana Tuta
  • Faculty of Medicine
Tănase Tasenţe
  • Faculty of Law and Administrative Sciences
Oana Arghir
  • Faculty of Medicine
Information
Address
Mamaia 124, Constanţa, Constanţa, Romania
Head of institution
Rector: Prof. univ. dr. Sorin Rugina
Website
www.univ-ovidius.ro