Topological description of complex patterns of bonding, charge transference and structural changes in chemical reactions: SN2 type reactions, a case study

Author(s):  
Rosana M. Lobayan ◽  
Roberto C. Bochicchio ◽  
Alejandro Daniel Marturet
Land ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 234
Author(s):  
Dong Han ◽  
Jiajun Qiao ◽  
Qiankun Zhu

Rural-spatial restructuring involves the spatial mapping of the current rural development process. The transformation of land-use morphologies, directly or indirectly, affects the practice of rural restructuring. Analyzing this process in terms of the dominant morphology and recessive morphology is helpful for better grasping the overall picture of rural-spatial restructuring. Accordingly, this paper took Zhulin Town in Central China as a case study area. We propose a method for studying rural-spatial restructuring based on changes in the dominant and recessive morphologies of land use. This process was realized by analyzing the distribution and functional suitability of ecological-production-living (EPL) spaces based on land-use types, data on land-use changes obtained over a 30-year observation period, and in-depth research. We found that examining rural-spatial restructuring by matching the distribution of EPL spaces with their functional suitability can help to avoid the misjudgment of the restructuring mode caused by the consideration of the distribution and structural changes in quantity, facilitating greater understanding of the process of rural-spatial restructuring. Although the distribution and quantitative structure of Zhulin’s EPL spaces have changed to differing degrees, ecological- and agricultural-production spaces still predominate, and their functional suitability has gradually increased. The spatial distribution and functional suitability of Zhulin are generally well matched, with 62.5% of the matched types being high-quality growth, and the positive effect of Zhulin’s spatial restructuring over the past 30 years has been significant. We found that combining changes in EPL spatial area and quantity as well as changes in functional suitability is helpful in better understanding the impact of the national macro-policy shift regarding rural development. Sustaining the positive spatial restructuring of rural space requires the timely adjustment of local actors in accordance with the needs of macroeconomic and social development, and a good rural-governance model is essential.


2021 ◽  
Vol 13 (6) ◽  
pp. 3323
Author(s):  
Nishtman Karimi ◽  
Hossein Azadi ◽  
Kobe Boussauw

Continuously changing conditions of sociotechnical systems are the basis of structural changes in communities. Relationships between transition contexts and regime transformation processes and their driving factors in sociotechnical regimes are poorly understood. Moreover, not all changes in multilevel governance regimes are geared towards sustainability, as demonstrated by the case of the water management regime in Sanandaj county in the west of Iran between 1962 and 2018. The current study shows how the management regime of water resources in the case study has changed over time and identifies the institutional arrangements through a retrospective analysis. The analysis is based on three stages of data collection which included a discussion group, a Delphi survey, and a focus group survey among various types of stakeholders. The “Hybrid Transitions” framework is introduced in order to denote processes of regime change that take place in a range of different transition contexts. The findings do not identify a single transition pathway but show that a number of parallel transition pathways have occurred in the context of groundwater and surface water management and their respective institutional arrangements. The study provides a better understanding of the complexity of transition pathways that were devised at the management regime level.


2021 ◽  
Vol 26 (5) ◽  
pp. 30-38
Author(s):  
E. A. Savchuk ◽  
E. P. Golubinskaya ◽  
T. N. Shcherbinina ◽  
G. Yu. Voronin ◽  
E. O. Savchuk ◽  
...  

The article presents an analysis of the literature and a clinical case of a rare disease from the group of diseases of small vessels — cerebral autosomal dominant arteriopathy with subcortical infarction and leukoencephalopathy (CADASIL).It is based on the deposition of osmiophilic granulation material in vessels of small and medium caliber. A mutation in the NOTCH3 gene on chromosome 19p13 leads to significant structural changes in the walls of small arteries due to impaired differentiation and maturation of smooth muscle cells.CADASIL is characterized by four key symptoms: migraines, recurrent ischemic strokes, mental disorders, and cognitive decline. The clinical case study is presented from the standpoint of a multidisciplinary patient-oriented approach of joint work of neurologists and morphologists. On the basis of clinical and laboratory criteria, a probable diagnosis was made. To confirm it, a muscle biopsy was performed (a musculocutaneous flap from the inner surface of the thighs and forearms), in order to conduct light and electron microscopy. The details of the results of the morphological study, which made it possible to verify the patient’s diagnosis, are presented. Differential diagnostic judgments are presented and recommendations for genetic studies in the family, prognosis and treatment of the patient are given.


2021 ◽  
Vol 109 ◽  
pp. 53-58
Author(s):  
Ulrich Diederichs ◽  
Sandra Jäntsch ◽  
Dorothea Sklenářová

In the course of repairs or upgrading measures, it is often necessary to provide floors with synthetic resin coatings. After the work has been carried out, bubbles may form. The article lists the various mechanisms that cause blistering (osmotic pressure, impurities in the aggregate of the screed or concrete, chemical reactions, e.g. alkali silica reaction). By aid of a case study, the procedure for determining the causes of blistering is given in more detail. The investigations have shown that the formation of bubbles was due to alkali-silica reactions of opal sandstone particles in the screed.


2017 ◽  
Author(s):  
Abigail C. Snyder ◽  
Robert P. Link ◽  
Katherine V. Calvin

Abstract. Hindcasting experiments (conducting a model forecast for a time period in which observational data is available) are rarely undertaken in the Integrated Assessment Model (IAM) community. When they are undertaken, the results are often evaluated using global aggregates or otherwise highly aggregated skill scores that mask deficiencies. We select a set of deviation based measures that can be applied at different spatial scales (regional versus global) to make evaluating the large number of variable-region combinations in IAMs more tractable. We also identify performance benchmarks for these measures, based on the statistics of the observational dataset, that allow a model to be evaluated in absolute terms rather than relative to the performance of other models at similar tasks. This is key in the integrated assessment community, where there often are not multiple models conducting hindcast experiments to allow for model intercomparison. The performance benchmarks serve a second purpose, providing information about the reasons a model may perform poorly on a given measure and therefore identifying opportunities for improvement. As a case study, the measures are applied to the results of a past hindcast experiment focusing on land allocation in the Global Change Assessment Model (GCAM) version 3.0. We find quantitative evidence that global aggregates alone are not sufficient for evaluating IAMs, such as GCAM, that require global supply to equal global demand at each time period. Additionally, the deviation measures examined in this work successfully identity parametric and structural changes that may improve land allocation decisions in GCAM. Future work will involve implementing the suggested improvements to the GCAM land allocation system identified by the measures in this work, using the measures to quantify performance improvement due to these changes, and, ideally, applying these measures to other sectors of GCAM and other land allocation models.


2006 ◽  
Vol 45 (4II) ◽  
pp. 797-817
Author(s):  
Toseef Azid ◽  
Naeem Khaliq ◽  
Muhammad Jamil

Development of overall economy of any country largely depends upon the characteristics of different prominent sectors such as agriculture, industry, services, etc. Sharp structural change in prominent sectors are experienced by the Pakistan’s economy during the last four decades, in which industrial and service sector have exhibited an extra ordinary rate of growth, while the agricultural sector did not shown that rate of growth which was experienced during the time of green revolution. Due to these structural changes in the prominent sectors volatility of growth rate has been experienced by the economy. To the extent that most of the recent volatility in growth rate of GDP can be attributed to the increasing share of the some volatility of the some prominent sectors, the analysis of their volatility can be useful in providing some enlightenment on the factors behind this phenomenon and its implications for the formulation of the policy in the future.


2020 ◽  
Vol 16 (4) ◽  
pp. 1-13
Author(s):  
Vera Silva ◽  
Jesualdo Cerqueira Fernandes

The benefits management methodology is a complementary analysis technique to traditional project management practices. It dynamically evaluates the benefits associated with the implementation of an information system (IS), including all phases from planning to monitoring, both during and after the implementation. This article presents a case study of the application of the Cranfield School of Management's benefits management technique as it is applied to an insurance company. It identifies and quantifies the underlying benefits of IS implementation, organizational and structural changes, and alignment with the organization's strategy. The data was collected through analysis of secondary documents and interviews with insurance company employees. The main contribution of this article is to demonstrate the versatility of the Cranfield School of Management's technique during the study of IS projects. It provides a graphical visualization of the dependencies between all elements of the network.


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