scholarly journals Challenges in a population policy toward migrations under the conditions of uneven distribution of population potentials in Serbia

2018 ◽  
pp. 651-662
Author(s):  
Danica Santic
Keyword(s):  
Population Distribution ◽  
Population Policy ◽  
Uneven Distribution ◽  
Geographical Pattern ◽  
High Concentration ◽  
Historical Factors ◽  
Territorial Structure ◽  
Key Topics ◽  
Migration Flows ◽  
Different Levels

Population distribution, as one of the key topics in geographical research, reflects the integrity of physical, social, economic and historical factors of certain area. This paper provides an overview of the spatial concentration of population in Serbia at the beginning of XXI century (Censuses 2002 and 2011). The analysis of population distribution and redistribution was performed at different levels of territorial structure of Serbia. The results indicate uneven distribution of population potentials (both in quantitative and qualitative ways) by expanding the area of extremely low and extremely high concentration. However, there remains a need for a broader scientific consideration of migration flows in order to create migration policies. Those policies are of interest to geographers because they represent attempts to manage the flow of people and to alter the geographical pattern of population distribution and characteristics.

Compartments, wingless and engrailed: patterning the ventral epidermis of Drosophila embryos

Development ◽  
1996 ◽  
Vol 122 (12) ◽  
pp. 4095-4103 ◽  
Author(s):  
P.A. Lawrence ◽  
B. Sanson ◽  
J.P. Vincent
Keyword(s):  
Pattern Formation ◽  
Wing Disc ◽  
High Concentration ◽  
Good Region ◽  
Steep Slopes ◽  
Cuticular Structures ◽  
Different Levels ◽  
Promote Cell Death ◽  
Drosophila Embryos

Recent experiments on the wing disc of Drosophila have shown that cells at the interface between the anterior and posterior compartments drive pattern formation by becoming the source of a morphogen. Here we ask whether this model applies to the ventral embryonic epidermis. First, we show that interfaces between posterior (engrailed ON) and anterior (engrailed OFF) cells are required for pattern formation. Second, we provide evidence that Wingless could play the role of the morphogen, at least within part of the segmental pattern. We looked at the cuticular structures that develop after different levels of uniform Wingless activity are added back to unsegmented embryos (wingless- engrailed-). Because it is rich in landmarks, the T1 segment is a good region to analyse. There, we find that the cuticle formed depends on the amount of added Wingless activity. For example, a high concentration of Wingless gives the cuticle elements normally found near the top of the presumed gradient. Unsegmented embryos are much shorter than wild type. If Wingless activity is added in stripes, the embryos are longer than if it is added uniformly. We suggest that the Wingless gradient landscape affects the size of the embryo, so that steep slopes would allow cells to survive and divide, while an even distribution of morphogen would promote cell death. Supporting the hypothesis that Wingless acts as a morphogen, we find that these stripes affect, at a distance, the type of cuticle formed and the planar polarity of the cells.

scholarly journals A Comparative Study on Soft Law: Lessons from the COVID-19 Pandemic

2021 ◽  
pp. 1-34
Author(s):  
Barbara BOSCHETTI ◽  
Maria Daniela POLI
Keyword(s):  
Legal Theory ◽  
Theory And Practice ◽  
Soft Law ◽  
General Interest ◽  
Hard Law ◽  
Regulatory Strategies ◽  
Key Topics ◽  
Negative Impacts ◽  
Different Levels ◽  
Shed Light

Abstract This article aims to map how soft law tools have complemented and supported the overall regulatory strategies implemented by European countries to counter the Covid-19 crisis (the soft law atlas), to shed light on some key topics of general interest for legal theory and practice: how soft law tools interact and complement one another including on different levels (the soft law web), how soft law tools interact and complement the sources of pandemic law (the interplay between soft and hard law), and the positive and negative impacts on governance and policy-making of soft law tools during the pandemic and beyond (soft law bright and dark sides).

scholarly journals Biochemical Dymorphism of Potassium Content and its Adaptive Significance in Domestic Reindeer

2021 ◽  
Vol 285 ◽  
pp. 03005
Author(s):  
Alexander Yuzhakov ◽  
Anatoly Kushnir ◽  
Kasim Laishev ◽  
Vasily Zabrodin
Keyword(s):  
Whole Blood ◽  
Rangifer Tarandus ◽  
Potassium Content ◽  
Average Level ◽  
Extreme Conditions ◽  
Adaptive Responses ◽  
High Concentration ◽  
Gene Frequencies ◽  
High Potassium ◽  
Different Levels

The connection between the types of potassium concentration and the ecogenesis of the studied groups of animals, with the degree of extreme conditions of breeding, with types of potassium in extreme conditions of breeding is known. In this regard, studies on autochthonous species of ungulates in the Subarctic are of great interest, the most numerous of which is the reindeer (Rangifer tarandus). Comparative analysis of the adaptive responses of NK and LK types at different levels of organization confirmed the presence of the adaptive advantage of animals characterized by a hereditarily high concentration of potassium in the blood in ecological-geographical zones with extreme environmental conditions. As a result of a study on domesticated reindeer, a clearly expressed dimorphism in the level of potassium in the blood was revealed, due to a genetically controlled high NK and low LK concentration. The average level of potassium in whole blood in the studied population of reindeer is 26.94 ± 0.56 meq/l with a variability of 24.61%. It was revealed that the average level of potassium content in whole blood by sex and age was distributed as follows: whales 22.97 - 25.80 meq/l at P> 0.05, castrate bulls had indicators significantly higher than 28.37 - 29.58 meq / l, at P> 0.05, the young showed intermediate indicators - 27.37 - 28.13 at P> 0.05. The intragroup variability in potassium content in whole blood ranged from 15.5 to 31.05%. It was found that in domestic reindeer the ratio of animals of the high-potassium (HK) type is 88.02% and of the lowpotassium (LK) type - 11.98%, while the gene frequencies for highpotassium animals are 0.9381.

scholarly journals RESORT RESOURCES OF THE COUNTRY AS THE MAIN COMPONENT OF THE SYSTEM OF TOURIST LOCAL HISTORY

2021 ◽  
Vol 76 (3) ◽  
pp. 145-155
Author(s):  
Daryna A. Liuta ◽  
◽  
Eduard A Kryvolapov ◽  
Eugene G. Bortnikov ◽  
◽  
...  
Keyword(s):  
Supply And Demand ◽  
Local History ◽  
Hierarchical Level ◽  
High Concentration ◽  
Consumer Market ◽  
Settlement Systems ◽  
Production And Consumption ◽  
Territorial Structure ◽  
Main Component ◽  
Different Order

The resort is a narrowly specialized territorial entity with a relatively high concentration of relevant specialization functions (balneological, climatotherapeutic and others). The relative territorial homogeneity of resort resources contributes to the formation of areal forms − resort areas, districts and resort areas. That is, the elements that are formed by the subjects-producers of the producer's market, depending on the level of territorial specialization and concentration of tourist activity, can be divided into tourist-excursion and resort. That is, territorial structures are markets of supply of different hierarchical level, complexity and specialization, to which consumer flows are directed and which provide the process of consumption of tourist goods and a certain set of tourist services. The key elements of the territorial structure of the tourist market are the nodes (resorts). Thus, the geospatial structure of the market of tourist services is formed by both sides of the market − the consumer market, forming demand, localizes it in the elements of settlement systems, based on which the demand market is formed and to which the intermediary enterprises to specialization, is localized both in the elements of settlement systems, tending to the centers of concentration of demand, as well as in the territorial structures of different order and specialization, on the basis of which the supply market is formed. Therefore, the article singles out the main scientists who studied resort activities. Also, the article defines the purpose − the characteristics of resort resources as an important component of tourist science. After the study of the outlined problem, conclusions were made based on the objectives. It is determined that the market of tourist services is a system of multifaceted, polystructural, polyform and multilevel system, which operates according to the law of balancing supply and demand, which reproduces the objectively determined need for compliance in time and space. commodity supply, and operates on the basis of fluctuations in production and consumption of tourism products. And resorts in turn are an important element of the tourist market.Keywords: resorts, territorial structure, tourist market, tourism, tourist services.

scholarly journals Bitcoin Transaction Networks: An Overview of Recent Results

2020 ◽  
Vol 8 ◽  
Author(s):  
Nicoló Vallarano ◽  
Claudio J. Tessone ◽  
Tiziano Squartini
Keyword(s):  
Distributed Systems ◽  
Structural Properties ◽  
Network Structure ◽  
Structural Organization ◽  
Uneven Distribution ◽  
Exchange Markets ◽  
Different Levels ◽  
Over Time ◽  
Centralized System

Cryptocurrencies are distributed systems that allow exchanges of native (and non-) tokens between participants. The availability of the complete historical bookkeeping opens up an unprecedented possibility: that of understanding the evolution of a cryptocurrency's network structure while gaining useful insights into the relationships between users' behavior and cryptocurrency pricing in exchange markets. In this article we review some recent results concerning the structural properties of the Bitcoin Transaction Networks, a generic name referring to a set of three different constructs: the Bitcoin Address Network, the Bitcoin User Network, and the Bitcoin Lightning Network. The picture that emerges is of a system growing over time, which becomes increasingly sparse and whose mesoscopic structural organization is characterized by the presence of an increasingly significant core-periphery structure. Such a peculiar topology is accompanied by a highly uneven distribution of bitcoins, a result suggesting that Bitcoin is becoming an increasingly centralized system at different levels.

scholarly journals Analysis of level, pattern, and determinants of population flows between Bahia and São Paulo

2018 ◽  
Author(s):  
Ernesto F. L. Amaral
Keyword(s):  
Specific Area ◽  
Sao Paulo ◽  
Metropolitan Region ◽  
São Paulo ◽  
Census Tracts ◽  
Migration Data ◽  
Low Education ◽  
Low Levels ◽  
Migration Flows ◽  
Different Levels

Title in Portuguese: Análise do nível, padrão e determinantes dos fluxos populacionais entre Bahia e São PauloAbstract: The main goal of this research is to analyze whether the pattern of concentration of migrants in a specific area of destination is the same as that of the area of origin of those migrants. The 2000 Brazilian Census has migration data for regions of origin (municipality) and destination (group of census tracts). Migration flows from 415 municipalities in the state of Bahia to 875 groups of census tracts in the mesoregion (metropolitan region) of São Paulo are analyzed. In Bahia, migrants are more likely to leave municipalities with low levels of education, which are surrounded by municipalities with the same levels of education. In São Paulo, migrants are more likely to move into areas with low education, and high proportion of population working, which are surrounded by areas with different levels in covariates. Low-skilled migrants are moving into areas with higher opportunities of jobs, but with low-skilled population.Resumo: A migração do Nordeste para São Paulo era caracterizada por fluxos de áreas rurais para áreas urbanas nas décadas de 1960 e 1970. Pessoas de classes sociais desfavorecidas migravam, e ainda migram, do Nordeste para São Paulo em busca de emprego. Nas últimas décadas, a migração interna se tornou mais complexa, com uma maior variedade de lugares de origem e destino, assim como uma mudança nas características sócio-econômicas dos migrantes. A análise descritiva de concentração dos migrantes sugeriu que os municípios com baixas taxas de emigração estão localizados em áreas mais desenvolvidas da Bahia. Os grupos de municípios com alta emigração se situam em áreas centrais do Estado, as quais são conhecidas por apresentarem baixos índices sócio-econômicos e de desenvolvimento. Em relação à análise de concentração de imigrantes na mesorregião de São Paulo, observa-se que os grupos de áreas de ponderação com altas taxas de imigração estão espalhados no oeste e nordeste dessa malha urbana. As áreas com baixas taxas de imigração estão concentradas nas áreas centrais da mesorregião e no sudeste dessa área urbana. Em relação aos modelos de regressão espacial, os resultados estatisticamente significantes indicam que os migrantes da Bahia para São Paulo tendem a apresentar baixa escolaridade e se dirigem para áreas com altas oportunidades de empregos, mas com uma população no destino que também apresenta baixos níveis educacionais.

scholarly journals PERFORMANCE OF BROILER CHICKEN FED DIFFERENT LEVELS THYME, ADIANTUM, ROSEMARY AND THEIR COMBINATION

2019 ◽  
Vol 50 (6) ◽  
Author(s):  
TAYEB & et al.
Keyword(s):  
Body Weight ◽  
Medicinal Plants ◽  
Broiler Chicken ◽  
Thymus Vulgaris ◽  
Broiler Chicks ◽  
High Concentration ◽  
Blood Biochemical ◽  
Live Body Weight ◽  
Medical Plants ◽  
Different Levels

The objective of this study was to investigate the effects of different levels of medical plants (thymus vulgaris, Adiantum capillus-veneris L, Rosemarinus officinalis and their combination) supplemented in the diet on Physiological and Growth performance traits of broiler chicken. T1 Control (no supplemented), T2 Thyme powder 5 g/kg, T3 Thyme powder 10 g/kg, T4 Adiantum powder 3 g/kg, T5 Adiantum powder 5 g/kg, T6 Rosemary powder 5 g/kg, T7 Rosemary powder 10 g/kg and T8 Mixture (Thyme , Adiantum and Rosemary) with 7.5 g/kg +4 g/kg and 7.5 g/kg, respectively. A Total of 288 unsexed broiler chicks, were randomly distributed to eight treatments with three replicate. Medical plants at different levels added to basal diets at 7th days old. Live body weight and mortality rates were measured weekly. At the end of the experiment the following traits were measured: carcass traits, hematology, blood biochemical, hormonal responses, and serum enzymes parameters. There is a significant effect of medicinal plants on live body weight, feed intake and dressing percentage. Mortality rate in T2 and T7 was significant highest. While, feed conservation  was not influenced by medicinal plants. There was a significant effect of treatments on abdominal fat and liver weights. Adiantum powder at different levels has significant effect on bursa and spleen weights compared to other groups. There was a significant effect of treatments on albumin, globulin, cholesterol and glucose concentration. Medicinal plants significantly affect hormonal response. The combination of plants (T8) investigated high concentration of T3 and T4 hormones. Also, addition of rosemary observed higher concentration of TSH and GH hormones. There was significant effect of medical plants on AST and ALT enzymes. There is none significant effect of medical plants on meat color among treatment.

scholarly journals An equity and efficiency integrated grid-to-level 2SFCA approach: spatial accessibility of multilevel healthcare

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Shaoyao Zhang ◽  
Xueqian Song ◽  
Jie Zhou
Keyword(s):  
Population Distribution ◽  
Analytical Framework ◽  
Decision Makers ◽  
Spatial Accessibility ◽  
Significant Heterogeneity ◽  
Behavior Simulation ◽  
Operational Solution ◽  
Equity And Efficiency ◽  
Primary Healthcare Centers ◽  
Different Levels

Abstract Background Equity of healthcare spatial access is essential for the health outcomes of medical investments and the welfare of populations, and efficiency of medical resource allocation is important for obtaining a supply-demand equilibrium with lower cost and higher outputs with limited inputs. However, the literature that involves both equity and efficiency in its analysis of healthcare spatial allocation is rare, and the spatial accessibility of multilevel healthcare is difficult to measure by traditional methods in a large region with diversified population distribution. Methods To assist in solving these issues, this paper aims to build an equity and efficiency integrated analytical framework by proposing a new “GTL-2SFCA” approach to analyze the spatial accessibility of multilevel healthcare; maximum and minimum floating catchments of different levels of healthcare were assigned to ensure a combination of universal search coverage and efficient hospitalization behavior simulation. Results The analytical framework was applied and tested in Hubei, China. Almost half of the residents (47.95%) and townships (44.98%) have access to both public general hospitals (PGHs) and primary healthcare centers (PHCs) services, 36.89% of the residents enjoy only one sufficient service, either PGHs or PHCs, and the remaining residents (15.16%) are faced with the risk of lacking access to both services. The results reveal that there are core-periphery effects of multilevel healthcare throughout Hubei and isolate clusters that have adequate access in the western region. The polarization effect of higher-level healthcare and the polycentric pattern of lower-level healthcare coexist. The multilevel healthcare shortage was identified in some areas in boundary and peripheral regions. Conclusions This study integrates equity and efficiency into the GTL-2SFCA framework, enriches the FCA series methodologies and provides a more operational solution for evaluating the access of residents in more sophisticated spatial units to each level of healthcare. By more significantly differing and quantifying the catchment area and distance decay effect, this methodology avoids overestimating or underestimating accessibility and discovers some imperceptible spatial inequities. This study has application value for researchers and decision-makers in other scenarios and regions with significant heterogeneity in medical resources and where the population has greater mobility.

Investigation of Evacuated Tube Collector Performance at High Temperature Mode Using TRNSYS Simulation Model

2013 ◽  
Vol 465-466 ◽  
pp. 155-160
Author(s):  
Basil H. Ali ◽  
S.I. Gilani ◽  
Hussain Hamoud Al-Kayiem
Keyword(s):  
Simulation Model ◽  
Substantial Improvement ◽  
High Concentration ◽  
Evacuated Tube Collector ◽  
Temperature Mode ◽  
Collector Efficiency ◽  
Good Improvement ◽  
Evacuated Tube Collectors ◽  
Evacuated Tube ◽  
Different Levels

It has been proved that creation of vacuum between the absorber and the cover of a solar collector is resulting in a substantial improvement in the collector efficiency due to reduction in the heat loss through convection ad conduction. In this work, the performance of evacuated tube collectors is investigated using TRNSYS simulation model. Different levels of concentrations have been considered in the simulation to predict the power generation. The simulation results showed that the thermal performance of evacuated tube collectors with high concentration ratio can provide a good improvement to the receiver output.

Educating Migrant Children: Negotiations between the State and Civil Society

2004 ◽  
Vol 180 ◽  
pp. 1073-1088 ◽  
Author(s):  
Julia Kwong
Keyword(s):  
Civil Society ◽  
Population Policy ◽  
The State ◽  
Migrant Children ◽  
Floating Population ◽  
Educational Problem ◽  
Local Education ◽  
Different Levels

The development of migrant children schools in Beijing in the 1990s is used here to illustrate the changing state-society relationship in China. These schools emerged as an attempt by individuals to resolve an educational problem resulting from the retreat of the state in enforcing its population policy and its reluctance to educate children of the floating population gathered in the capital. These individuals used their own resources, and harnessed support from other sectors in the civil society as well as from some government units. Even though the local education departments did not take up the responsibility to educate children with household registrations outside Beijing, they did not give the migrant children schools recognition or support. This report traces the manoeuvres, negotiations and other strategies used by these schools to survive, by the different government units at different levels to contain them, and by others to support them. This struggle illustrates the growing heterogeneity inside government and the increasing strength of civil society in China.

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