bluuebunny/crossref_metadata_2025 huggingface dataset:
Perspectives about social support among unmarried pregnant university students in South Africa
Authors: Msipu Phiri Thandiwe , Nyamaruze Patrick , Akintola Olagoke
Published: April 2023

Background

Pregnant young women in an academic environment are susceptible to stressors associated with unintended pregnancy and academic demands of universities. The challenges they face may be exacerbated by lack of social support, putting them at risk of psychological disorders such as depression. Women who receive social support during pregnancy and postpartum experience less emotional distress and report greater maternal satisfaction. However, very little is known about the perspectives about social support among unmarried pregnant students in tertiary institutions.

Methods

Participants were purposively selected among unmarried pregnant students and those in the puerperal period at the time of the study. We conducted semi-structured qualitative interviews to explore the perspectives of unmarried pregnant students on the type of support that they need during pregnancy and the puerperium and the period when most support is needed. The data were audio-recorded and transcribed verbatim, then analysed using thematic analysis.

Results

The findings show that social supports (emotional, instrumental, informational, and financial) were highlighted as important resources to cope with stressors during pregnancy and post-birth. Emotional support from male partners was the most important type of support needed as it entailed a sense of being loved and cared for. Social support was identified as important throughout the different phases of pregnancy and post birth, with different support needs expressed at each of these phases.

Conclusion

This study identified support needs of unmarried pregnant university students in their transition to motherhood. Given the several challenges that they are faced with, unmarried pregnant students need social support, including male partner support to enhance wellbeing as they try to cope with academic and pregnancy-related stressors.
National cross-sectional study on cost consciousness, cost accuracy, and national medical waste reduction initiative knowledge among pediatric hospitalists in the United States
Authors: Lee Benjamin C. , Hall Matt , Agharokh Ladan , Yu Andrew G. , Parikh Kavita , Shah Samir S.
Published: April 2023

Background/objective

Despite initiatives to reduce waste and spending, there is a gap in physician knowledge regarding the cost of commonly ordered items. We examined the relationship between pediatric hospitalists’ knowledge of national medical waste reduction initiatives, self-reported level of cost-consciousness (the degree in which cost affects practice), and cost accuracy (how close an estimate is to its hospital cost) at a national level.

Methods

This cross-sectional study used a national, online survey sent to hospitalists at 49 children’s hospitals to assess their knowledge of national medical waste reduction initiatives, self-reported cost consciousness, and cost estimates for commonly ordered laboratory studies, medications, and imaging studies. Actual unit costs for each hospital were obtained from the Pediatric Health Information System (PHIS). Cost accuracy was calculated as the percent difference between each respondent’s estimate and unit costs, using cost-charge ratios (CCR).

Results

The hospitalist response rate was 17.7% (327/1850), representing 40 hospitals. Overall, 33.1% of respondents had no knowledge of national medical waste reduction initiatives and 24.3% had no knowledge of local hospital costs. There was no significant relationship between cost accuracy and knowledge of national medical waste reduction initiatives or high self-reported cost consciousness. Hospitalists with the highest self-reported cost consciousness were the least accurate in estimating costs for commonly ordered laboratory studies, medications, or imaging studies. Respondents overestimated the cost of all items with the largest percent difference with medications. Hospitalists practicing over 15 years had the highest cost accuracy.

Conclusions

A large proportion of pediatric hospitalists lack knowledge on national waste reduction initiatives. Improving the cost-accuracy of pediatric hospitalists may not reduce health care costs as they overestimated many hospital costs. Median unit cost lists could be a resource for educating medical students and residents about health care costs.
Prevalence and associated factors for self-reported symptoms of dry eye among Thai school children during the COVID-19 outbreak
Authors: Tonkerdmongkol Danai , Poyomtip Teera , Poolsanam Chotika , Watcharapalakorn Akarapon , Tawonkasiwattanakun Patarakorn
Published: April 2023

Purpose

COVID-19 pandemic caused an increase in digital screen time, which seemed to increase the prevalence of dry eye symptoms among the population with abnormally high digital screen usage hours. However, there are no reports of dry eye symptoms in school children with high digital usage hours. Therefore, the present study aimed to assess the prevalence of dry eye symptoms and evaluate the associated factors among school children aged 12 to 18 years during the COVID-19 outbreak.

Methods

Multistage cluster sampling was applied, and six sections of online questionnaires were distributed to selected respondents in November 2021. The odds ratio (OR) with confidence intervals (CIs) for the factors was calculated using binary logistic regression. All statistical significance was determined at p < 0.05.

Results

The findings revealed that 62.5% of 603 students showed symptoms of dry eye (DEQ-5 score ≥ 6). Significant associated factors included being female (adjusted OR (aOR) 1.54; 95% CIs 1.05–2.25), higher-grade student (aOR 1.77; 95% CIs 1.23–2.57), digital screen time use (6 to < 12 hours: aOR 2.00; 95% CIs 1.12–3.57, ≥12 hours: aOR 2.54; 95% CIs 1.39–4.76), and perceived stress (aOR 1.12; 95% CIs 1.08–1.16). The Thai-Perceived Stress Scale-10 scores were positively correlated with the scores on the 5-item dry eye questionnaire (Spearman’s r = 0.38, p-value < 0.01).

Conclusion

A high prevalence of dry eye symptoms might be common among school children during the COVID-19 outbreak. Significant risk factors include being female, being a higher-grade level student, prolonged use of digital screens, and perceived stress. However, contact lens use, smoking, and the most common digital device usage patterns were not found to be contributing factors.
Contamination of groundwater with sulfamethoxazole and antibiotic resistant Escherichia coli in informal settlements in Kisumu, Kenya
Authors: Karimi Kellen J. , Ngumba Elijah , Ahmad Aijaz , Duse Adriano G. , Olago Daniel , Ndwigah Stanley N. , Mwanthi Mutuku A. , Ayah Richard , Dulo Simeon
Published: April 2023

High frequency of antibiotic detection in groundwater in informal settlements is attributed to increased usage and improper disposal, thus difficult to identify sources of antibiotic resistance in the environment, worsened by inadequate sanitation facilities and increased population density, particularly in developing-countries. Reliance on groundwater exposes them to pollutants and risk of antibiotic resistance, in addition to experiencing inequities in accessing vital services. Sulfamethoxazole and trimethoprim, used for prophylaxis by HIV/AIDS patients were tested in 49 groundwater sources in Kisumu, Kenya. Only Sulfamethoxazole (SMX) was found, with a detection frequency of 14.3% and concentrations ranging from below limit of quantification (LOQ) to 258.2 ng/L. Trimethoprim (TMP), marketed in combination with sulfamethoxazole, was not detected, owing to its high distribution coefficient (kPa7.12) and, generally, being a bigger molecule with modest water mobility and solubility. Furthermore, TMP ratio in cotrimoxazole is low (5:1), it is expected that mass loading will be lower, as well as influence of the study area’s hydrogeology, where soil is clayey with high porosity and permeability. Escherichia coli was recovered in 98% (n = 48) of water samples, with counts ranging from 16 to 8,850 MPN/100ml. Additionally, resistance to sulfamethoxazole was identified in 6% (n = 3) samples with Inhibition Zone Diameters of 0.8mm(resistant), 10.5mm (resistant), and 11.5mm (intermediate), but not among samples where SMX was detected. Antibiotic concentrations in water that can cause resistance are unknown because antibiotic-resistant E. coli was not found in water samples where sulfamethoxazole was identified, raising concerns about f environmental resistance spread. Concentration of SMX was lower in a previous research, which only collected water from one groundwater source, than the current study, which included additional samples (49). Presence of SMX and Escherichia coli resistance is of concern and necessitates greater attention and regular monitoring for potential contaminants and resistance trigger to avert potential risks to human health.
The changing working life of photojournalism professionals in the contemporary media environment
Authors: Mäenpää Jenni
Published: April 2023

This article aims to pull together some of the recent trajectories that have affected the work of photojournalism professionals. It is argued that the hybrid media environment is yet another turning point of the revolutionary changes caused by the digitalization during the past three decades. Since the late 1980s the digitalization has enabled photojournalism much more than the transition of photo editing and cameras from analogue to digital technology. Digitalization has, for example, facilitated the work in numerous ways and enabled images to travel in multiple speed in comparison to analogue times. During the recent years, traditional media organizations have witnessed diminishing revenues of and cut downs of photography departments worldwide. Most of the news photographers of today are self-employed, and despite the growing importance of the visuals in society, they need to expand their reach from journalism to other fields such as commercial photography, public relations, corporate communications, artistic projects and NGO work to earn a living. This leads to blurring of boundaries between journalism and other fields and to diffusion of professional values and ethics.
Comunicar un estereotipo cultural. El caso de Persa de Plauto
Authors: González Saavedra Berta
Published: April 2023

Parto de la idea de que la comedia tanto griega nueva como latina se basan en tramas creadas a partir de personajes que funcionan como modelos, para analizar la obra Persa, en la que los personajes actúan dentro de ella para engañar al lenón. Para lograr el engaño, el disfraz adoptado es el de un persa y una princesa de Arabia, que provoca que el estereotipo que tiene el pueblo romano (y griego) sobre esos pueblos se active y esto hace que el engaño funcione, pues tanto el público como el lenón engañado comparten las mismas creencias sobre ellos. Además, los estereotipos sobre los persas son comparados con los de los fenicios, presentes en la comedia Poenulus, para tratar de justificar por qué los romanos tienen una imagen estereotipada tan diferente de persas y fenicios.
Escenas de saludo en los diálogos de Platón
Authors: Verano Rodrigo
Published: April 2023

El presente trabajo analiza las escenas de saludo representadas en los diálogos de Platón con auxilio de una metodología que combina las perspectivas antropológica y literaria. Partiendo de las características universales del saludo como rutina comunicativa, se explora su estilización literaria en el corpus platónico. Se distinguen así cinco partes distintas en la escena y se comprueba el mayor peso de los elementos no verbales (proxémicos, perceptivos y gestuales) en la recreación platónica del saludo. Esto explica que las escenas se den preferentemente en diálogos de tipo narrativo y se excluyan de los de tipo mimético
Vitalino Valcárcel Martínez (1944-2022)
Authors: Ruiz Arzalluz Iñigo
Published: April 2023

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Salagin (no Salus Augusta) en una inscripción de El Centenillo (Jaén)
Authors: Gimeno Helena , Velaza Frias Javier
Published: April 2023

En este trabajo defendemos que la lectura de la primera línea del ara romana de El Centenillo (Jaén), considerada tradicionalmente como una dedicación a Salus Augusta, debe ser rectificada y atribuida a Salagin. Es este el segundo testimonio de esta divinidad en una zona minera, en este caso en un contexto ibérico en el corazón de Oretania.
EFFECT OF FREEZING AND THAWING ON THE STRENGTH AND DURABILITY OF SANDY SUBGRADE CONTAINING FIBRILLATING NETWORK FIBER FOR PAVEMENT
Authors: Khabiri Mohammad Mehdi , Ebrahimialavijeh Bahareh
Published: April 2023

One of the challenges of road construction is encountering soils with lack of required strength and durability. Nowadays, various stabilization techniques are applicable for improving the engineering properties of soils. In the present study, dune sand, as subgrade of pavements, was treated using various contents of fibrillating network (FN) fiber and cement. Dune sand has low bearing capacity that makes it unsuitable for construction activities such as pavement applications. The common solution is improving the strength properties of dune sand so that it can be used for civil engineering projects. Stability of subgrade is very important since the layer provides the stability for the whole pavement structure and the upper layers, namely subbase, base, and asphalt layers. In this regard, compression strength and California bearing ratio (CBR) tests were carried out. Freezing-thawing cycle is one of the most important factors affecting the mechanical properties of soils. Several researchers reported that freezing-thawing cycle could change the physical and mechanical behaviours of soils. The influence of freezing and thawing (up to 18 cycles) on the properties of samples was also studied. Based on the results, the inclusion of FN-fiber to the sand led to increasing the ductility and compressive strength. Also, the addition of cement reduced the ductility, and increased the compressive strength. By increasing the freezing-thawing cycles, the soil strength significantly decreased. Results showed that the stabilized sand soil as subgrade layer led to reducing the compressive strain under the applied wheel load, and therefore reduced the possibility of rutting failure of subgrade.
EXPERIMENTAL STUDY ON THE SEISMIC DAMAGE OF AEOLIAN SAND CONCRETE COLUMNS WITH DIFFERENT REINFORCEMENTS
Authors: Wang Yaohong , Ma Xiaoyan , Han Qing , Chu Qi , Zhang Zeping
Published: April 2023

Aeolian sand is a kind of natural material with abundant reserves and a low price. Many scholars have conducted extensive studies on the engineering applications of aeolian sand. This paper addresses the seismic damage behaviour of aeolian sand concrete columns to promote the application of aeolian sand in frame structures. A total of 5 aeolian sand concrete column specimens with different reinforcements were studied using cyclic loading tests. The failure modes, stiffness degradation, bearing capacity, hysteresis peculiarity, ductility, and energy consumption of the specimens were analysed and compared. Then, applicable damage models of the specimens were proposed. The study results prove that the seismic damage behaviour of the specimens increases with the increase of longitudinal reinforcement percentage and with the transverse steel ratio when the replacement percentage of aeolian sand is constant. Additionally, the damage model which is revised in this paper agrees well with the test results. It can be used to assess the degree of damage to the aeolian sand concrete columns.
FIELD LOADING-TEST BASED SHM SYSTEM SAFETY STANDARD DETERMINATION
Authors: Yu Jiaping , Li Chunwei , Sun Quansheng
Published: April 2023

Structural health monitoring (SHM) allows for real-time structural response monitoring and online data acquisition of bridge structures. This data reflects the operational and environmental conditions of the bridge, which is important in identification of possible anomalous changes. In order to effortlessly determine the safety condition of the bridge directly through the transferred data without data analysis, a five-level safety standard system will be established for real-time safety warning in this paper. The threshold of each safety levels will be determined through field loading tests results on an external prestressing rehabilitated continuous rigid frame bridge, of which permanent structural health monitoring system was instrumented. After overall evaluation, we come to the conclusion that the rehabilitation is successful and that the bridge is under safe operating condition. A novel, simplified safety standard thresholding technique is proposed based on static loading test results as well as ultimate limit state of the bridge. This technique is simple yet very practical in daily bridge monitoring.
Impact of Migration on Non-Migrant School Completion Rates and Enrolment in South Africa
Authors:   Management College of Southern Africa, Nyika Farai , Shepherd Debra ,   University of Stellenbosch
Published: April 2023

South Africa struggles with low secondary school completion rates and this has a negative effect on poverty and inequality. In this study, we examine the relationship between internal migration (international migrants were excluded) and non-migrant educational outcomes (secondary school enrolment and completion rates) in South Africa between 1996 and 2011. We use census data for the years 1996, 2001 and 2011 (at the district and municipal levels) in several linear probability regression models that include the First Difference (FD) and System Generalised Method of Moments (GMM-SYS) with instrumental variables. The 2011 census is the latest available in South Africa now. We find that internal migrants have a positive effect on both enrolment and completion rates of non-migrants. These results vary in intensity depending on the level of education of both internal migrant and non-migrant household heads. These results have implications for the local labour market and for income inequality in South Africa; internal migrants provide positive peer effects that contribute to raising non-migration enrolment and completion. Internal migrants also provide job market competition which influences non-migrants to complete secondary schooling. There is scant empirical evidence on the impact of internal migration on education outcomes in African countries, especially in South Africa. Our paper provides evidence from a country with a history of persistent internal migration. Most prior research has focused on the relationship between immigration and education outcomes in the developed world. We recommend that government improves secondary school quality in rural and urban areas and increase study loans for students at tertiary institutions.
Who Wants to Go Where? Regional Variations in Emigration Intention in Nigeria
Authors:   University of Lagos, Alabi Tunde , Olajide Bamidele
Published: April 2023

There has been an increase in the number of Nigerians desperately leaving the country. In the absence of accurate data on the rate of actual emigration, this study investigated emigration intention in Nigeria, and how it varies between northern and southern Nigeria – two regions with perennial sociocultural differences that have been neglected in migration research. The study also investigated the factors associated with emigration intention. It utilized secondary data from the Afrobarometer survey, including 1,600 Nigerian adults aged 18 and above. Logistic regression models were fitted to address the study objectives. The study found that the emigration intention rate in Nigeria was 35.5%, but it varied from 30.3% in the north to 40.3% in the south. The rate ranged from 26% in the north-east to 46.4% in the south-eastern part of the country. The most preferred destination for northern Nigerians was another country in Africa (32.4%), but it was North America for southerners (43.2%). At the multivariate level, the study found that living in the south, being educated, using the internet frequently, having tolerance for homosexuals, and participating in politics increased the likelihood of emigration intention. However, being old, employed and having religious tolerance reduced the odds of emigration intention. The regional models revealed notable differences in the influence of age, education, employment, tolerance, and political participation. The study discusses the implications of the findings.
Scholars and Literati at the University of Coimbra (1290–1800)
Authors: De la Croix David , Gualandris Tifenn , Vitale Mara
Published: April 2023

This note is a summary description of the set of scholars and literati who taught at the University of Coimbra from its inception in 1290 to the eve of the Industrial Revolution (1800).
Mediating role of stock market volatility to evaluate asymmetries in the growth-degradation nexus in Nigeria
Authors: AlGhazali Abdullah , Musa Nana Ize , Ibrahim Saifullahi Sani , Samour Ahmed
Published: April 2023

This study explores the mediating role of stock market volatility in the economic growth and environmental degradation nexus in Nigeria using data covering period from 1984 until 2020. The study uses Nonlinear Autoregressive Distributed Lag (NARDL) and a nonparametric asymmetric causality model. While the Wald test in model 1 reveals evidence of weak long-run asymmetric nexus between CO2 and economic growth however, findings in model 2 indicates that stock market volatility (SMV) exerts a strong asymmetric effect in growth-CO2 relation in the long-run. The result of nonlinear model validates the inverted U-shaped growth-degradation nexus consistent with EKC hypothesis. The finding in model 1 reveals that investment exerts a strong impact on CO2 in both the short-run and long-run. On the other hand, the results in model 2 show that the positive component of economic growth has a positive and significant impact on CO2 in Nigeria. However, the negative component of economic growth has a negative impact on CO2. Moreover, the dynamic causality model reveals: (i) a feedback causality between CO2 and the negative component of GDP; and (ii) a unidirectional causality flowing from CO2 to the positive component of GDP. Similarly, result of nonlinear causality test reveals a feedback causality between CO2 and GDP. The implication of the finding suggests that while asymmetric properties of economic growth must be controlled in efforts of promoting environmental sustainability, the stock market has a dedicated role to play in widening access to funds for green investment in Nigeria and other developing economies.
Improvements of Ease of Doing Business and the Access to Justice in United Arab Emirates
Authors: Heikal Sherif
Published: April 2023

There is an enormous body of legal literature hypothesizing that differences in economic prosperity can be traced to the legal systems of countries, in the same vein, some research has posited that countries with a sophisticated legal system have enjoyed greater per capita growth than countries whose legal systems having operational shortcomings. Hence, this Article provides an assessment on the role of the access to justice and the ease of ease of doing business in United Arab Emirates. This article finds that the access to justice in UAE have played a crucial role for not only the ease of starting the business but also provided a general healthy business environment.
The Funding of The North Atlantic Treaty Organization
Authors: Matthijs Herman
Published: April 2023

This study examines the financing system of the budgets of the North Atlantic Treaty Organization (N.A.T.O.). The NATO is not a supranational organization, with partly exception of the military coordination by SHAPE, but an intergovernmental organization. So far, it’s the only existing military institution at present worldwide.  This 2023 study concerns only the three internal NATO budgets. Therefore, this article is based at the only reference material available, namely the primary budgetary sources of the NATO.   It must also be pointed out that NATO does prepare an annual report concerning the political and military situation. But there is no equivalent concerning an overview of its finances and administrative functioning. The aspects to be investigated are as follows:

who is funding the NATO budgets and how?
what happens with the money given to NATO?
how is NATO’s budget prepared and approved?

This article doesn’t treat the military budgets of the member states or the financing of the Parliamentary Assembly of the NATO.
Screening of medicinal mushroom strains with antimicrobial activity and polysaccharides production
Authors: Narmuratova Zhanar , Bisko Nina , Mustafin Kairat , Al-Maali Galeb , Kerner Alina , Bondaruk Svitlana , Suleimenova Zhanara , Kalieva Aigul , Akhmetsadykov Nurlan , Zhakipbekova Aigerim , Lomberg Margarita
Published: April 2023

Objectives

This study aimed to determine the antimicrobial activity of culture fluid and mycelial mass of selectedHericiumstrains from the IBK Mushroom Culture Collection (Kyiv, Ukraine) against bacteria and fungi, as well as to evaluate the potential of these mushrooms for biomass and extracellular polysaccharides production.

Methods

The antimicrobial activity of ethyl acetate extracts of culture fluid and aqueous-ethyl extracts of mycelial mass for threeHericiumspecies:Hericium cirrhatumIBK 2393,Hericium coralloidesIBK 2332, andHericium erinaceusIBK 2530 against Gram-positiveBacillus subtilis,Staphylococcus aureus, and Gram-negativeEscherichia coli,Klebsiella pneumoniae,Pseudomonas aureginosabacteria as well asAspergillus niger,Penicillium polonicum, andMucor globosusfungi by the disk diffusion method was conducted. Analysis of the minimum inhibitory concentration was carried out according to the broth dilution method.

Results

High antimicrobial activity of culture fluid extracts ofHericiummushroom species againstS. aureuswas established after 14–21 days of cultivation. No effects ofHericiumextracts againstA. niger,P. polonicum, andM. globosuswere observed. On the 7th day of submerged cultivation, the studied strains produced the maximum yield of extracellular polysaccharides. The most promising extracellular polysaccharide (EPS) producers were strains ofH. coralloidesIBK 2332 (1.89 g/L) andH. erinaceusIBK 2530 (1.90 g/L). The maximal value of biomass was produced byH. cirrhatumIBK 2393 on the 21st day of submerged cultivation (17.45 g/L).

Conclusions

Hericiummushrooms have significant potential for the development of new drugs with health benefits properties.
Increased Excitability and Synaptic Plasticity of Drd1- and Drd2-Expressing Prelimbic Neurons Projecting to Nucleus Accumbens after Heroin Abstinence Are Reversed by Cue-Induced Relapse and Protein Kinase A Inhibition
Authors: Kokane Saurabh S. , Cole Robert D. , Bordieanu Bogdan , Ray Chevin M. , Haque Ishraq A. , Otis James M. , McGinty Jacqueline F.
Published: April 2023

Dysregulation of the input from the prefrontal cortex (PFC) to the nucleus accumbens (NAc) contributes to cue-induced opioid seeking but the heterogeneity in, and regulation of, prelimbic (PL)-PFC to NAc (PL->NAc) neurons that are altered has not been comprehensively explored. Recently, baseline and opiate withdrawal-induced differences in intrinsic excitability of Drd1+(D1+) versus Drd2+(D2+) PFC neurons have been demonstrated. Thus, here we investigated physiological adaptations of PL->NAc D1+versus D2+neurons after heroin abstinence and cue-induced relapse. Drd1-Cre+and Drd2-Cre+transgenic male Long–Evans rats with virally labeled PL->NAc neurons were trained to self-administer heroin followed by 1 week of forced abstinence. Heroin abstinence significantly increased intrinsic excitability in D1+and D2+PL->NAc neurons and increased postsynaptic strength selectively in D1+neurons. These changes were normalized by cue-induced relapse to heroin seeking. Based on protein kinase A (PKA)-dependent changes in the phosphorylation of plasticity-related proteins in the PL cortex during abstinence and cue-induced relapse to cocaine seeking, we assessed whether the electrophysiological changes in D1+and D2+PL->NAc neurons during heroin abstinence were regulated by PKA. In heroin-abstinent PL slices, application of the PKA antagonist (R)-adenosine, cyclic 3′,5′-(hydrogenphosphorothioate) triethylammonium (RP-cAMPs) reversed intrinsic excitability in both D1+and D2+neurons and postsynaptic strength in only D1+neurons. Additionally,in vivobilateral intra-PL infusion of RP-cAMPs after abstinence from heroin inhibited cue-induced relapse to heroin seeking. These data reveal that PKA activity in D1+and D2+PL->NAc neurons is not only required for abstinence-induced physiological adaptations but is also required for cue-induced relapse to heroin seeking.

SIGNIFICANCE STATEMENTNeuronal plasticity in the medial prefrontal cortex is thought to underlie relapse to drug seeking, yet the subpopulation of neurons that express this plasticity to functionally guide relapse is unclear. Here we show cell type-specific adaptations in Drd1-expressing versus Drd2-expressing prelimbic pyramidal neurons with efferent projections to nucleus accumbens. These adaptations are bidirectionally regulated during abstinence versus relapse and involve protein kinase A (PKA) activation. Furthermore, we show that disruption of the abstinence-associated adaptations via site-specific PKA inhibition abolishes relapse. These data reveal the promising therapeutic potential of PKA inhibition for preventing relapse to heroin seeking and suggest that cell type-specific pharmacologies that target subpopulations of prefrontal neurons would be ideal for future therapeutic developments.
Coordination of Locomotion by Serotonergic Neurons in the Predatory GastropodPleurobranchaea california
Authors: Lee Colin A. , Brown Jeffrey W. , Gillette Rhanor
Published: April 2023

Similar design characterizes neuronal networks for goal-directed motor control across the complex, segmented vertebrates, insects, and polychaete annelids with jointed appendages. Evidence is lacking for whether this design evolved independently in those lineages, in parallel with segmentation and appendages, or could have been present in a soft-bodied common ancestor. We examined coordination of locomotion in an unsegmented, ciliolocomoting gastropod, the sea slugPleurobranchaea californica, which may better resemble the urbilaterian ancestor. Previously, bilateral A-cluster neurons in cerebral ganglion lobes were found to compose a multifunctional premotor network controlling the escape swim and feeding suppression, and mediating action selection for approach or avoidance turns. Serotonergic As interneurons of this cluster were critical elements for swimming, turning, and behavioral arousal. Here, known functions were extended to show that the As2/3 cells of the As group drove crawling locomotion via descending signals to pedal ganglia effector networks for ciliolocomotion, and were inhibited during fictive feeding and withdrawal. Crawling was suppressed in aversive turns, defensive withdrawal, and active feeding, but not during stimulus-approach turns or pre-bite proboscis extension. Ciliary beating was not inhibited during escape swimming. These results show how locomotion is adaptively coordinated in tracking, handling, and consuming resources, and in defense. Taken with previous results, they also show that the A-cluster network acts similarly to the vertebrate reticular formation with its serotonergic raphe nuclei in facilitating locomotion, postural movements, and motor arousal. Thus, the general scheme controlling locomotion and posture might well have preceded evolution of segmented bodies and articulated appendages.

SIGNIFICANCE STATEMENT:

Similar design in the neuronal networks for goal-directed motor control is seen across the complex, segmented vertebrates, insects, and polychaete annelids with jointed appendages. Whether that design evolved independently or in parallel with complexity in body and behavior has been unanswered. Here it is shown that a simple sea slug, with primitive ciliary locomotion and lacking segmentation and appendages, has similar modular design in network coordination as vertebrates for posture in directional turns and withdrawal, locomotion, and general arousal. This suggests that a general neuroanatomical framework for the control of locomotion and posture could have arisen early during the evolution of bilaterians.
Strategies of Political Control under Kim Jong Un
Authors: Ward Peter , Katzeff Silberstein Benjamin
Published: April 2023

In this article, we trace the strategy of political control employed in North Korea under Kim Jong Un. Using conceptual tools created in the literature on comparative authoritarianism, we consider the roles of repression, co-optation, coercive distribution, and containment with respect to how the North Korean regime responds to external and internal threats. We focus on two areas as case studies in differentiated, contingent political control strategies. First, we consider the role of border as a conduit for unauthorized goods, migrants, and illicit information and the regime’s regulation of it. Second, we examine the regime’s management of internal economic actors, namely urban entrepreneurs and farmers. The main argument of this article is that Kim Jong Un has employed a policy of simultaneous co-optation, repression, and latterly under COVID-19, reemergent coercive distribution, building on but also modifying the strategic approaches pursued under Kim Jong Il.
Electrical properties of TiO2/CO3O4 core/shell nanoparticles synthesized by sol-gel method
Authors:   Department of Chemistry and Chemical Technologies, University of Calabria,87036 Rende, Cosenza, Italy, Iqbal W. , Mekki M. ,   Physical chemistry laboratory of mineral materials and their application, National center for research in materials sciences, technopark Borej Cedria, Soliman, Tunisia, Rehman W. ,   Department of Chemistry, Hazara University, Mansehra, Pakistan., Shahzad B. ,   Soochow Institute for Energy and Materials Innovations, College of Energy, Soochow University, Suzhou 215006, China, Anwar U. ,   Laboratory of Materials Science and Nanotechnology (LMNT), Department of Biomedical Sciences, University of Sassari, CR-INSTM, Viale San Pietro, 07100, Sassari, Italy, Mahmood S. ,   Department of Zoology, University of Chakwal, Chakwal 48800, Pakistan, Talukder Md. E. ,   Institute on membrane technology, (CNR-ITM), Via Pietro BUCCI, 87036, Rende, Cosenza, Italy
Published: April 2023

TiO2/Co3O4 core-shell nanoparticles were successfully synthesized by the sol-gel method in two steps: the first step is the sol-gel synthesis of Co3O4 nanoparticles, and the second step is the synthesis of TiO2/Co3O4 nanoparticles by sol-gel method. The obtained Co3O4 and TiO2/Co3O4 core-shell nanoparticles were investigated utilizing X-ray diffraction, scanning electron microscopy, Fourier transforms infrared spectroscopy, diffuse reflectance spectroscopy, and conductivity measurement. X-ray diffraction analysis showed the presence of both Co3O4 and TiO2 phases in TiO2/Co3O4 core-shell nanoparticles; co3o4 nanoparticles have a cubic shape, and TiO2 nanoparticles have a tetragonal shape. SEM images of Co3O4 nanoparticles show most of the particles are smoothly distributed, having separate boundaries, and images of TiO2/Co3O4 nanoparticles showed that with an increase in calcination temperature, the size of the core-shell nanoparticles also increases. FTIR spectrum of both confirms the synthesis of Co3O4 and TiO2/Co3O4 nanomaterials. Diffuse reflectance spectroscopy exhibited the band gaps of TiO2/Co3O4 core-shell nanoparticles decrease with the increase of the temperature. The conductivity of the TiO2/Co3O4 core-shell nanomaterials increases with an increase in temperature and also with an increase in frequency.
Facile fabrication of 3D graphene hydrogel (rGH) for enhanced removal of heavy metal Cr (VI)
Authors:   North China University of Science and Technology, College of Metallurgy and Energy, Hebei Provincial High-Quality Steel Continuous Casting Engineering Technology Research Center, Tangshan Hebei 063210, Li Y. , Zhao X. Y. ,   Tangshan Open University ,Tangshan Hebei 063210, Guo X. C. ,   North China University of Science and Technology，Yisheng College，Tangshan Hebei 063210, Wang J. ,   North China University of Science and Technology，Yisheng College，Tangshan Hebei 063210, Chen W. ,   North China University of Science and Technology, College of Metallurgy and Energy, Hebei Provincial High-Quality Steel Continuous Casting Engineering Technology Research Center, Tangshan Hebei 063210
Published: April 2023

The reduced graphene hydrogel (rGH) was prepared by chemical reduction method, and removal performance of heavy metal Cr (VI) in static water was studied. The rGH has a three-dimensional structure and narrow pore size distribution, that the adsorption process of Cr (VI) by rGH is in accordance with Langmuir isotherm model, and the maximum adsorption capacity is 139.6 mg·g-1 .The significant adsorption capacity is mainly attributed to the fact that rGH has nano-sheet structure, and maintains the surface adsorption characteristics of graphene with rapid adsorption. The π-π action will reduce the competitive adsorption of water and increase the adsorption capacity.
Terahertz detection of chemicals through zeonex fiber material
Authors:   Faculty of Engineering, the University of Sydney, NSW-2006, Australia, Hossain M. B. , Alsalem K. A. J. ,   Department of Medical Instrumentation Engineering Techniques, Al-Kunooze University College, Basra, Iraq, Ahmed K. ,   Department of Electrical and Computer Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9, Canada, Bui F. M. ,   Department of Electrical and Computer Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9, Canada, Ibrahim S. M. ,   e Department of Biochemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia, Patel S. K. ,   Computer Engineering Department, Marwadi University 360003, Gujarat, India
Published: April 2023

A PCF sensor is proposed for chemical (e.g., glycerol, acetic acid, and water) sensing through Zeonex fiber material. We investigate relative sensitivity, effective are, effective material loss, and confinement loss to analyze the sensor performance. The proposed sensor offers the relative sensitivity of almost 97.7% for glycerol, 96.25% for acetic acid, 95.28% for water at frequency 3.5 THz. In addition, the sensor possesses small effective material loss and tiny confinement loss that are important characteristics of an efficient chemical sensor. Furthermore, the modern fabrication techniques are well fitting for the fabrication of the presented sensor.
I W Rowlands, Barbara J Weir and the biology of the hystricomorph rodents
Authors: Carter Anthony M , Acuña Francisco , Barbeito Claudio G
Published: April 2023

In brief

Current research on the genomics, ecology and reproductive biology of hystricomorph rodents relies on the pioneering studies of B J Weir and I W Rowlands. We show the enduring influence of a symposium on hystricomorph biology held 50 years ago.

The rodent suborder Hystricomorpha comprises seven families from Africa and Asia and ten from South America, where they have undergone an extensive radiation and occupy a variety of biomes. Although the guinea pig was a common laboratory rodent, little was known about reproductive biology in the other species until the ambitious research programme of Barbara Weir and her mentor I W Rowlands. Much of their work and of others then in the field was summarized at a symposium held 50 years ago at The Zoological Society of London. Currently, there is a resurgence of interest in the reproductive biology of the South American species. Compared to other rodents, unique features include a long gestation, a long oestrous cycle, a tendency to form accessory corpora lutea and a vaginal closure membrane. There is a distinctive placental structure, the subplacenta. Most give birth to precocial young. Individual species exhibit peculiarities such as polyovulation, systematic fetal loss and an active female prostate. Here, we highlight the achievements of Barbara Weir and show how her legacy has been sustained in the twenty-first century by South American scientists.
Sklerostin ve TWEAK’in Periodontitis Teşhisindeki Rolü
Authors: GÜNER Ece , TÜTER Gülay
Published: April 2023

Periodontitis multifaktöriyel etiyolojisi olan kronik inflamatuar bir hastalıktır. Hastalık biofilm içerisindeki patojenler tarafından başlatılmaktadır. Hastalık ilerledikten sonra görülen doku yıkımı konağa ait koruyucu ve yıkıcı mekanizmalar arasındaki dengesizlikten kaynaklanır. Periodontal hastalığın teşhisinde kullanılan geleneksel yöntemler, hastalık aktivitesi ve prognozuna ilişkin bilgi vermemektedir. Bu konuda son yıllarda sklerostin ve tümör nekroz faktörü benzeri zayıf apoptoz indükleyicisinin (TWEAK) inflamasyon ve kemik metabolizması üzerindeki etkileri incelenmeye başlanmıştır. Bu derlemenin amacı, sklerostin ve TWEAK’in periodontal hastalık patogenezindeki rolünün değerlendirilmesi ve sklerostin ve TWEAK’in periodontal hastalık teşhisi için yararlı birer biyobelirteç olup olmadığının incelenmesidir.
Farklı İrreversibl Hidrokolloid Ölçü Materyallerinin Zamana Bağlı Boyutsal Değişimlerinin Karşılaştırılması
Authors: TÜRK Ayşe Gözde , KÜMBÜLOĞLU Övül , ALADAĞ Akın
Published: April 2023

Amaç: İrriversibl-hidrokolloid ölçü materyallerinin, firmaların belirttiği bekleme zamanlarının, model netliğini ve ölçünün boyutsal stabilitesini etkileyip etkilemediğinin araştırılmasıdır.
Gereç ve Yöntemler: İki aljinat ölçü materyali Hydrocolor 5 (Zhermack), Colorchange (Cavex) ve 1 polivinilsiloksan ölçü materyali (kontrol) kullanıldı. Her materyal için paslanmaz çelikten ana modelden 50 ölçü alındı. Ölçü materyalleri hemen alçısı dökülen ve 1, 2, 3, 5 gün sonra alçısı dökülen gruplar oluşturuldu (n=10). Modellerden dijital kaliper ile ölçümler yapılarak ölçü materyallerinin boyutsal stabiliteleri karşılaştırıldı. Data tek yönlü ANOVA, Bonferroni ve t testleri ile istatistiksel olarak analiz edildi.
Bulgular: Boyutsal stabiliteyi açısından materyal-zaman etkileşimi anlamlı bulundu (p=0.007). 1. gün, Affinis-DCode – Hydracolor (p=0.015) ve Affinis-DCode – Cavex (p=0.011) arasındaki fark anlamlı; Hydracolor - Cavex arasındaki fark istatistiksel anlamsızdır. 5. gün, Affinis-DCode – Hydracolor (p=0.012), Affinis-DCode – Cavex (p<0.001) ve Hydracolor – Cavex (p<0.001) ölçü maddeleri arasında fark anlamlı bulundu. Hydrocolor (p=0.189) ve Affinis-DCode (p=0.436) için boyutsal değişim istatistiksel olarak anlamsız iken, Cavex 2. ve 5. gün değerlerinde boyutsal değişim anlamlı düzeyde artmıştır. (p=0.003). Bağımsız iki grup t testi ile yapılan değerlendirmede ise başlangıç da gruplar arası fark yok iken 1. 2. 3. ve 5. günlerde farklar istatistiksel olarak anlamlıdır.
Sonuç: Başlangıçta irreversibl-hidrokolloid ölçü maddeleri benzer davranış gösterse de, 5. Gün değerlendirmelerinde Cavex en fazla boyutsal değişime uğradı. Farklı marka ve bekleme zamanları irreversibl-hidrokolloid ölçü materyallerinin boyutsal stabilitesini etkilemektedir. Klinik açıdan en doğru yaklaşım, alınan ölçülerden en kısa sürede model eldesinin yapılması boyutsal değişimi minimum seviyede tutacaktır.
How do Mandibular Osteotomies with and without Le Fort I osteotomy affect the Mentolabial Groove from the frontal view?
Authors: SUZEN Muazzez , DİLAVER Emrah , ÖZEL Abdullah , UÇKAN Sina
Published: April 2023

Purpose: The aim of this study was to determine how the mentolabial groove at the frontal view is affected by orthognathic surgery. Materials & Methods: Sixty-two patients were appointed into two groups (Group 1: Class II skeletal deformity, Group 2: Class III skeletal deformity). In each patient, pre and postoperative standardized sixth-month photos (lateral and frontal view) were obtained in natural head position to investigate mentolabial groove length (MGL), mentolabial groove depth (MGD), mentolabial groove angle (MGA) and mentolabial angle (MLA). Results: Out of the 62 patients, 41 had Class III skeletal deformity (66.2%) and 21 Class II skeletal deformity (33.8%). In Group 1, the average ratio of MGL decreased significantly from 0.59±0.14 to 0.45±0.09 (p<0.001). Contrary to Group 1, the ratio of MGL increased significantly from 0.41±0.11 to 0.50±0.13 in Group 2 (p=0.001). There was a negative correlation between MGA and MGL (p=0.001, r=-0.439). MGD positively correlated with MGL (p<0.001, r=0.499). Conclusion: After orthognathic surgery, the mentolabial groove decreases in class II patients and increases in class III patients. Orthognathic surgery significantly affects mentolabial anatomy and therefore should be planned carefully to obtain an aesthetic appearance in the mentolabial region.
COVID-19 Pandemisinin Diş Hekimliği Öğrencilerinin Kariyer ve Uzmanlık Tercihlerine Etkisinin Değerlendirilmesi
Authors: GÖNDER Hakan Yasin , FİDAN Muhammet , DEMİREL Mehmet Gökberkkaan , SOYBELLİ Mehmet , TUNCDEMİR Ali Riza
Published: April 2023

Amaç: Sağlık hizmetine ihtiyacın arttığı pandemi döneminde, sağlık merkezleri bulaş riskine açık yerler haline geldiğinden elektif işlemler ertelenmiş, sağlık merkezleri pandemi koşullarına uygun şekilde çalışmaya başlandı. Birçok alanda olduğu gibi diş hekimliği alanı da COVID-19 pandemisinden etkilendi. Bu çalışmanın amacı; COVID-19 pandemisinin diş hekimliği öğrencilerinin kariyer ve uzmanlık eğitimi planlarına etkisini değerlendirmektir. Gereç ve Yöntemler: Çalışmaya anket formunu eksiksiz dolduran 259 diş hekimliği öğrencisi dahil edildi. Hazırlanan anket internet ortamında Google Forms kullanılarak katılımcılara ulaştırıldı. Anket formu içerisinde demografik bilgiler, öğrencilerin uzmanlık branşları hakkındaki kariyer planlarının COVID-19 pandemisi sebebiyle değişiklik gösterip göstermediği sorgulandı. Gruplar arası farklılıkların belirlenmesi amacıyla Pearson ki-kare testi kullanıldı (p<0.05). Bulgular: COVID-19 pandemisinin “mesleği uygularken eskiye göre daha fazla oranda bulaşıcı hastalığa yakalanma korkusu” kadın katılımcılarda erkeklere göre daha yüksek bulundu (p=0.004). Katılımcıların sınıflarına göre “uzmanlık eğitimi için hasta ile daha düşük riskli temasta olacağını düşündüğü branşlara olan ilginin artmaya başlamasına” ilişkin yanıtları bakımından birinci sınıflarda 'Evet' yanıtı dördüncü ve beşinci sınıflara kıyasla daha yüksek bulundu (p=0.003). “Mezuniyet sonrası kariyer tercihleri” bakımından kadın katılımcıların büyük çoğunluğu uzmanlık eğitimi almayı isterken, erkek katılımcılar kendi muayenehanesini açma ve özel sektörde çalışma yönündeki hedefleri kadınlara göre daha yüksek bulundu (p<0.05). Sonuç: Diş hekimliği öğrencileri COVID-19 pandemisi nedeniyle hastalar ile daha az yakın temasta olacakları bir uzmanlık dalı arayışındadır. COVID-19 pandemisi sürecinde bulaşıcı hastalığa yakalanma korkusu, diş hekimliği öğrencilerinin uzmanlık alanı seçimini etkileyen faktörler arasındadır.