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Topic Review
Urban Fragility
Urban fragility is one of the big challenges for the late-modern city coping with the growing external pressures (from the environment) and internal tensions (within the social system), typically referable to the socio-cultural and political-economic climate, definitely characterising the current "Age of Changes". A broad institutional context is involved in that undertaking, and many studies and reports show how fragility is linked above all to the growing complexity of the cities. The ever-increasing population, extension, density and cultural mixite, as well as the fast “filtering up and down” processes, are some symptoms of the combination of two fundamental drivers. Firstly, the exponential technological progress—mostly concerning the geographical and digital accessibility—has been encouraging far more people to claim a better socio-economic status, which urban location, by definition, is symbol of. Secondly, the progressive human/environmental unfairness of economy over the planet and the related increase in insecurity, push the transfer of large masses of the population towards the richer countries of the developed geo-economic areas, and in particular towards the larger, more heterogeneous, complex and vibrant cities. This new climate involves the accountability of the neoliberal model allowing a limited number of subjects to concentrate the largest part of the liquidity created as a result of the progressive “financial abstraction” of the real wealth over the era of post-globalization, that is the age of the contemporary archipelago-economies. The development of the city has always gone together with the spread and reinforcement of the financial institutions more able to give a monetary shape to the flows of wealth, thus indirectly increasing the part of the surplus of social product intended to the social overhead capital; the latter is at the same time cause and effect of the concentration of wealth and people, activities and tensions, conflicts and hopes (in one word, of value) in urban shapes. On the urban-scale, in turn, such processes have been occurring creating and populating denser and denser built areas at the expenses of other ones (decaying historic centers or peripheral neighborhoods) progressively neglected and jeopardized. The coexistence of such different value density degrees increases the fragility of the city as a whole; the most visible and permanent tracks of these inequalities reflect in the urban shape and namely in its economic form that is the urban capital value shape, displayed by the real estate market price map. Some remarks about the concept of fragility in the field of territorial studies can help to better understand how the urban eco-social system deals with it. The perspective of the “real estate-scape”, in fact, assumes the social and urban fragility issue, since one of the main focuses of the urban renovation planning process in its broad lines. The colloquial meaning of “fragility” closely relates to its physical definition concerning the tendency of a solid material to break abruptly, without any yielding deformation, which has previously occurred. In the urban studies some insights need to be done to understand a conceptual significance of fragility, considering its original causes and those effects typically concerning the current drift of the urban phenomenon. Since the above early definition does not take into account the driving forces of the urban fragility and their most perceptible effects, a further and more extensive meaning of it can be derived from material sciences, thus highlighting the deep and constitutive causes of it. Fragility is “the property that characterizes how rapidly the dynamics of a material slow down as it is cooled toward the glass transition: materials with a higher fragility have a relatively narrow glass transition temperature range, while those with low fragility have a relatively broad glass transition temperature range”. By metaphorizing such definition, and referring to the relationship between the socio-economic situation of a city and the real estate capital asset value, an urban system can be considered more fragile when the “socio-economic cooling” (i.e., a decrease in rights and incomes) gives rise to sudden, pathological and irreversible fall of the real estate market prices; on the contrary, an urban system seems to be more resilient when such effects are slower and easily metabolized, and can also be reversed when an opposite cause occurs. Furthermore, “physically, fragility may be related to the presence of dynamical heterogeneity in glasses, as well as to the breakdown of the usual Stokes–Einstein relationship between viscosity and diffusion”.
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  • 14 Jul 2020
Topic Review
Intestinal Tryptophan Metabolism Pathways
Tryptophan (Trp) is an essential aromatic amino acid that is acquired exclusively through dietary intake in humans (since Trp is not produced by animal cells). Common sources of dietary Trp are fish, poultry, cereals, and dairy foods. The World Health Organization advises an intake of 4 mg of Trp/kg/day. Trp is a precursor of several microbial and host metabolites, including several molecules such as serotonin, melatonin, nicotinamide and vitamin B3. The intestine is a prime location of Trp metabolism. Three main metabolic pathways can process dietary Trp: (i) the kynurenine pathway (KP) via indoleamine 2,3-dioxygenase (IDO)1, mainly occurring in both immune and epithelial cells, (ii) the serotonin (5-hydroxytryptamine [5-HT]) pathway via Trp hydroxylase 1 (TpH1) in enterochromaffin cells, and finally (iii) the direct conversion of Trp by the intestinal microbiota into several. 
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  • 19 Apr 2021
Topic Review
Additive Manufacturing and Circular Economy
Additive Manufacturing (AM), also known as three-dimensional (3D) printing has emerged as a disruptive and powerful tool for industrial systems in the Industry 4.0 era by helping businesses flourish in the contemporary dynamic competitive landscape. However, their achievements and development highly rely on “take-make-waste” linear business models, which come, all too often, to the detriment of the environment. Hence, a shift to Circular Economy (CE) practices promoting the acceleration of the transition to resource-efficient systems and the minimization of environmental degradation is now more imperative than ever. 
  • 2.2K
  • 17 Jun 2021
Topic Review
Tougher Plastics Ban Policies in China
After the Chinese government's new plastics ban policies issued in 2020, another set of tougher plastics ban measures were introduced in Shanghai, China in 2021. The tougher plastic ban polices completely forbade the usage of plastic carrier bags and required all supermarkets to sell only cloth or nylon carrier bags priced from RMB 1.0 to 39.0. Tougher plastics ban policies are penalty-oriented. The tougher plastics ban policies produce positive plastics reducing effects by observing significantly decreased usage of charged carrier bags by 46%, and significantly increased usage of old plastic bags and reusable bags by 117% and 36%, respectively. Policy execution loopholes are found in some supermarkets which do not follow the tougher plastics ban measures. Fortunately, the spill-over effects from tougher-measure-executing supermarkets fix this issue to some extent. The tougher 2021 measures fail to be the most powerful impacting factor on people’s usage of each type of bag. To produce better plastics reducing results, other bag-targeted measures are necessary.
  • 2.2K
  • 19 Oct 2021
Topic Review
Vaginal pH Value in Common Vaginitis
In modern society, 75% of all women worldwide have had vaginitis at least once in their lives. The vagina has a dynamic microbial ecosystem with varying vaginal pH levels. An imbalance in that ecosystem can alter the vaginal pH and tip the scale to the point of causing issues, such as vaginitis, that require medical attention. Although vaginitis is not an incurable disease, it causes discomfort and pain that disrupt women’s daily lives. The most common causes of vaginitis include bacterial vaginosis, trichomoniasis, and vulvovaginal candidiasis. In this review, we discuss the causes, diagnostic methods, and symptoms of different types of vaginitis, the relationship of vaginitis to the prevalence of other diseases, issues associated with recurrent vaginitis and the immune system, and a variety of effective available treatments.
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  • 03 Nov 2021
Topic Review
Tryptophan Metabolic Pathways in Migraine-Related Mechanisms
Migraine is a complex neurovascular disorder, which causes intense socioeconomic problems worldwide. The pathophysiology of disease is enigmatic; accordingly, therapy is not sufficient. Migraine research focused on tryptophan, which is metabolized via two main pathways, the serotonin and kynurenine pathways. Both produce neuroactive molecules that influence pain processing and stress response by disturbing neural and brain hypersensitivity and interacting with molecules that control vascular and inflammatory actions. Serotonin has a role in trigeminal pain processing, and melatonin, another product of this pathway, also has a role in these processes. One of the end products of the kynurenine pathway is kynurenic acid (KYNA), which can decrease the overexpression of migraine-related neuropeptides in experimental conditions. However, the ability of KYNA to cross the blood-brain barrier is minimal, necessitating the development of synthetic analogs with potentially better pharmacokinetic properties to exploit its therapeutic potential.
  • 2.2K
  • 05 Dec 2022
Biography
Percy Spencer
Percy Lebaron Spencer (July 19, 1894 – September 8, 1970) was an United States physicist and inventor. He became known as the inventor of the microwave oven.[1] Spencer was born in Howland, Maine. Eighteen months later, Spencer's father died, and his mother soon left him in the care of his aunt and uncle. His uncle then died when Spencer was just seven years old. Spencer subsequently left g
  • 2.2K
  • 27 Dec 2022
Topic Review
Ethical Marketing and Brand Loyalty
The attainment of brand loyalty is based on programs related to the corporate marketing. Typically, brand loyalty is reflected in how customers evaluate the company’s outlook towards the product evaluation and consumer-brand relations. A company’s ethical marketing practices affect the daily routine of consumer activity. Every company’s ethical marketing practices are closely related to the purchase of products or services, regardless of whether it is conscious of consumer purchasing power strengths and weaknesses. The importance of ethics in the advancement of business sustainability, and general marketing issues (including product safety, price tags and advertising) has duly been recognized by corporate managers and vendors. As an outcome, an economic behavior, whether ethical or non-ethical, is inherently linked with a company’s overall reputation and assessment, and stresses the fundamental factors in keeping the company competitive on the market. Ethical marketing practice plays a significant role in improving consumer-firm ties, product assessment, and brand loyalty. 
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  • 05 Jul 2021
Topic Review
Chitosan in Lowering Cholesterol
Chitosan is one of the polymers containing acetyl glucosamine and glucosamine.
  • 2.2K
  • 28 Jan 2021
Topic Review
Biomass Feedstock
The importance of energy demands that have increased exponentially over the past century has led to the sourcing of other ideal power solutions as the potential replacement alternative to the conventional fossil fuel. However, the utilisation of fossil fuel has created severe environmental issues. The identification of other renewable sources is beneficial to replace the energy utilisation globally. Biomass is a highly favourable sustainable alternative to renewable resources that can produce cleaner, cheaper, and readily available energy sources in the future. The palm oil industry is essentially ideal for the availability of abundant biomass resources, where the multifaceted residues are vital for energy production through the conversion of biomass waste into value-added products simultaneously. This article discusses the utilisation of palm oil and its residues in the energy and transportation sector. Assessment and evaluation on the feasibility of palm oil and its residues were made on the current valorisation methods such as thermochemical and biochemical techniques. Their potential as transportation fuels were concurrently reviewed. This is followed by a discussion on future challenges of palm oil industries that will take place globally, including the prospects from government and non-government organisations for the development of palm oil as a sustainable alternative replacement to fossil fuel. Hence, this review aims to provide further insight into the possibilities of palm oil and its residues towards sustainable development with reduced environmental-related issues.
  • 2.2K
  • 29 Jul 2021
Topic Review
Snowmelt Models
The snowmelt model is a hydrological model that simulates the processes of snow accumulation, melt, and confluence. Since the snowmelt process involves the complex energy transfer and water transfer processes between the atmosphere and snow, between different snow layers, and between snow layers and soil, it is more complicated than the formation process of rainfall runoff. If there is a rainfall event on snow, it is very difficult to simulate the runoff generation process due to the mixture of rain and snow. Snowmelt simulation is the basis for the simulation of snowmelt flood formation processes, and it plays a crucial role in accurately modelling snowmelt floods.
  • 2.2K
  • 29 Oct 2021
Topic Review
Selenium Nanoparticles (SeNPs)
Elemental selenium (Se0) is naturally insoluble, displays a lower toxicological potential and can form selenium nanoparticles (SeNPs).
  • 2.2K
  • 25 Feb 2022
Topic Review
Blockchain in Fintech
Banks were the primary players in the financial services landscape. However, as a result of technological and entrepreneurial advancements, new business models have emerged, introducing new participants such as start-ups and technology firms into to the mix. This development has significantly altered how businesses and retail customers manage their finances. These new disruptive companies, as well as the components that contributed to it, are now commonly referred to as “Fintech”. 
  • 2.2K
  • 29 Jun 2022
Topic Review
CTCF and Its Partners in 3D Genome
The 3D genome organization and its dynamic modulate genome function, playing a pivotal role in cell differentiation and development. CCCTC-binding factor (CTCF) and cohesin, acting as the core architectural components involved in chromatin looping and genome folding, can also recruit other protein or RNA partners to fine-tune genome structure during development. Moreover, systematic screening for partners of CTCF has been performed through high-throughput approaches. In particular, several novel protein and RNA partners, such as BHLHE40, WIZ, MAZ, Aire, MyoD, YY1, ZNF143, and Jpx, have been identified, and these partners are mostly implicated in transcriptional regulation and chromatin remodeling, offering a unique opportunity for dissecting their roles in higher-order chromatin organization by collaborating with CTCF and cohesin.
  • 2.2K
  • 26 Aug 2022
Topic Review
Causes and Pathophysiology of Acquired Sideroblastic Anemia
The sideroblastic anemias are a heterogeneous group of inherited and acquired disorders characterized by anemia and the presence of ring sideroblasts in the bone marrow. Ring sideroblasts are abnormal erythroblasts with iron-loaded mitochondria that are visualized by Prussian blue staining as a perinuclear ring of green-blue granules. The mechanisms that lead to the ring sideroblast formation are heterogeneous, but in all of them, there is an abnormal deposition of iron in the mitochondria of erythroblasts. Congenital sideroblastic anemias include nonsyndromic and syndromic disorders. Acquired sideroblastic anemias include conditions that range from clonal disorders (myeloid neoplasms as myelodysplastic syndromes and myelodysplastic/myeloproliferative neoplasms with ring sideroblasts) to toxic or metabolic reversible sideroblastic anemia. Due to the advances in genomic techniques, a deep knowledge of the pathophysiological mechanisms has been accomplished and the bases for possible targeted treatments have been established. The distinction between the different forms of sideroblastic anemia is based on the study of the characteristics of the anemia, age of diagnosis, clinical manifestations, and the performance of laboratory analysis involving genetic testing in many cases.
  • 2.2K
  • 13 Sep 2022
Topic Review
Autistic Enterocolitis
Autistic enterocolitis is the name of a nonexistent medical condition proposed by discredited United Kingdom gastroenterologist Andrew Wakefield when he suggested a link between a number of common clinical symptoms and signs which he contended were distinctive to autism. The existence of such an enterocolitis has been dismissed by experts as having "not been established". Wakefield's fraudulent and now-retracted report used inadequate controls and suppressed negative findings, and multiple attempts to replicate his results have been unsuccessful. Reviews in the medical literature have found no link between the MMR vaccine and autism or bowel disease. Most of Wakefield's coauthors later retracted the conclusions of the original paper proposing the hypothesis, and the General Medical Council found Wakefield guilty of manipulating patient data and misreporting results. His work has been exposed as falsified and described as an "elaborate fraud".
  • 2.2K
  • 14 Oct 2022
Topic Review
Bioinformatics in Plant Breeding and Disease Resistance
In the context of plant breeding, bioinformatics can empower genetic and genomic selection to determine the optimal combination of genotypes that will produce a desired phenotype and help expedite the isolation of these new varieties. Bioinformatics is also instrumental in collecting and processing plant phenotypes, which facilitates plant breeding. Robots that use automated and digital technologies to collect and analyze different types of information to monitor the environment in which plants grow, analyze the environmental stresses they face, and promptly optimize suboptimal and adverse growth conditions accordingly, have helped plant research and saved human resources.
  • 2.2K
  • 02 Dec 2022
Topic Review
Water Physisorbed on Natural Clinoptilolite
Infrared spectroscopy (FT-IR) can provide very useful information on the nature of water physisorbed on zeolites. The vibrational characteristics of geomorphic clinoptilolite of natural origin and the water physically adsorbed on it have been investigated. In particular, two types of physisorbed water molecules have been identified by combining the FT-IR analysis with a mild thermal drying treatment (1h at 150°C) of the sample: the loosely-bound water and the tightly-bound water.
  • 2.2K
  • 29 Oct 2020
Topic Review
Hydrogen Peroxide
Hydrogen peroxide (H2O2) is an important oxidation molecule regulating aerobic metabolism. Redox signals include physiological oxidative stress (EU stress), and excessive oxidative stress can damage molecules. The main enzyme sources of H2O2 are nicotinamide adenine dinucleotide phosphate oxidase or NADPH oxidase (NOx), mitochondrial respiratory chain and various kinds of oxidase. NOx family consists of seven enzyme subtypes, which produce a superoxide anion (O2 -) which can be converted to H2O2 by superoxide dismutase or spontaneously. H2O2 passes through the membrane through some aquaporin (AQP), which is called porphyrin hydroperoxide. It diffuses in cells and tissues, triggering cellular effects such as proliferation, immune cell recruitment and morphological changes. 
  • 2.2K
  • 27 Jan 2022
Topic Review
Mitochondria and NLRP3 Inflammasome Interplay
Mitochondria are the power plants of the cell responsible not only for the generation of cellular energy required for myriad functions but also are important hubs for metabolism, reactive oxygen species (ROS) generation, and Ca2+ homeostasis. Inflammasomes are a group of intracellular multicomplexes located in the cytosol which detect PAMPs and DAMPs and produce the activation, maturation, and release of pro-inflammatory cytokines (including IL-1β and IL-18).
  • 2.2K
  • 23 May 2022
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