As the crucial non-cellular component of tissues, the extracellular matrix (ECM) provides both physical support and signaling regulation to cells. Some ECM molecules provide a fibrillar environment ...around cells, while others provide a sheet-like basement membrane scaffold beneath epithelial cells. In this Review, we focus on recent studies investigating the mechanical, biophysical and signaling cues provided to developing tissues by different types of ECM in a variety of developing organisms. In addition, we discuss how the ECM helps to regulate tissue morphology during embryonic development by governing key elements of cell shape, adhesion, migration and differentiation.
•The first formalization of a CLSC network of distributed plastic recycling for 3D printing.•Assessment of the economical–environmental feasibility of the distributed recycling network.•A sensitivity ...analysis of the distributed recycling undertaken using real parameters.•A first model to decision-making process to sustain distributed recycling initiatives at early stages.
Recent research and initiatives increasingly propose a new approach, based on distributed plastic recycling for open-source (OS) 3D printing technologies, as a way to deal with the issue of plastic waste and to support the development of the circular economy (CE). Distributed recycling can be thought of as a sort of “smart grid”, composed of small and coordinated recycling units. However, the operational complexity of this distributed approach limits its application. Furthermore, the environmental and economic advantages have yet to be demonstrated. This article therefore explores the economic and environmental feasibility of this distributed plastic recycling approach from a logistics perspective, as a step towards its validation. To achieve this, an optimization mixed integer linear programming (MILP) model was used as an evaluation tool, representing a local closed loop supply chain (CLSC) network. The proposed model is illustrated using a case study of a university seeking to implement a distributed recycling demonstrator in order to recover 3D printing wastes from secondary schools in the northeast of France. Following this step, a sensitivity analysis was carried out considering the market variations (price of virgin plastic filament) and the amount of available plastic waste derived from the schools. The results obtained show positive economic and environmental benefits of carrying out this new method of plastic recycling. This work serves as a basis for continuing to explore the feasibility and replication of the distributed plastic recycling network in other contexts.
The rapid technical evolution of additive manufacturing (AM) enables a new path to a circular economy using distributed recycling and production. This concept of Distributed Recycling via Additive ...Manufacturing (DRAM) is related to the use of recycled materials by means of mechanical recycling process in the 3D printing process chain. This paper aims to examine the current advances on thermoplastic recycling processes via additive manufacturing technologies. After proposing a closed recycling global chain for DRAM, a systematic literature review including 92 papers from 2009 to 2019 was performed using the scopus, web of science and springer databases. This work examines main topics from six stages (recovery, preparation, compounding, feedstock, printing, quality) of the proposed DRAM chain. The results suggested that few works have been done for the recovery and preparation stages, while a great progress has already been done for the other stages in order to validate the technical feasibility, environmental impact, and economic viability. Potential research paths in the pre-treatment of recycled material at local level and printing chain phases were identified in order to connect the development of DRAM with the circular economy ambition at micro, meso and macro level. The development of each stage proposed using the open source approach is a relevant path to scale DRAM to reach the full technical potential as a centerpiece of the circular economy.
The potential of exosomes as biomarker resources for diagnostics, prognostics and even for therapeutics is an area of intense research. Despite the various approaches available, there is no consensus ...with respect to the best methodology for isolating exosomes and to provide substantial yields with reliable quality. Differential centrifugation is the most commonly used method but it is time-consuming and requires large sample volumes, thus alternative methods are urgently needed. In this study two precipitation-based methods and one column-based approach were compared for exosome isolation from distinct biofluids (serum, plasma and cerebrospinal fluid). Exosome characterization included morphological analyses, determination of particle concentration, stability and exosome preparations' purity, using different complementary approaches such as Nanoparticle Tracking Analysis, Electrophoretic Light Scattering, Transmission Electron Microscopy, EXOCET colorimetric assay, protein quantification methods and western blotting. The three commercial kits tested successfully isolated exosomes from the biofluids under study, although ExoS showed the best performance in terms of exosome yield and purity. Data shows that methods other than differential centrifugation can be applied to quickly and efficiently isolate exosomes from reduced biofluid volumes. The possibility to use small volumes is fundamental in the context of translational and clinical research, thus the results here presented contribute significantly in this respect.
Summary
Asthma is a complex respiratory disorder characterized by marked heterogeneity in individual patient disease triggers and response to therapy. Several asthma phenotypes have now been ...identified, each defined by a unique interaction between genetic and environmental factors, including inflammatory, clinical and trigger‐related phenotypes. Endotypes further describe the functional or pathophysiologic mechanisms underlying the patient's disease. type 2‐driven asthma is an emerging nomenclature for a common subtype of asthma and is characterized by the release of signature cytokines IL‐4, IL‐5 and IL‐13 from cells of both the innate and adaptive immune systems. A number of well‐recognized biomarkers have been linked to mechanisms involved in type 2 airway inflammation, including fractional exhaled nitric oxide, serum IgE, periostin, and blood and sputum eosinophils. These type 2 cytokines are targets for pharmaceutical intervention, and a number of therapeutic options are under clinical investigation for the management of patients with uncontrolled severe asthma. Anticipating and understanding the heterogeneity of asthma and subsequent improved characterization of different phenotypes and endotypes must guide the selection of treatment to meet individual patients’ needs.
Mammalian development demands precision. Millions of molecules must be properly located in temporal order, and their function regulated, to orchestrate important steps in cell cycle progression, ...apoptosis, migration and differentiation, to shape developing embryos. Ubiquitin and its associated enzymes act as cellular guardians to ensure precise spatio-temporal control of key molecules during each of these important cellular processes. Loss of precision results in numerous examples of embryological disorders or even cancer. This Review discusses the crucial roles of E3 ubiquitin ligases during key steps of early mammalian development and their roles in human disease, and considers how new methods to manipulate and exploit the ubiquitin regulatory machinery - for example, the development of molecular glues and PROTACs - might facilitate clinical therapy.
•Laminar burning velocities of a gasoline and of model fuels (n-heptane, iso-octane, and toluene).•Influence of ethanol of commercial gasoline and model fuel investigated up to 15%(vol).•The results ...have been simulated using an updated detailed kinetic model.
The adiabatic laminar burning velocities of a commercial gasoline and of a model fuel (n-heptane, iso-octane, and toluene mixture) of close research octane number have been measured at 358K. Non-stretched flames were stabilized on a perforated plate burner at 1atm. The heat flux method was used to determine burning velocities under conditions for which the net heat loss of the flame is zero. Very similar values of flame velocities have been obtained for the commercial gasoline and for the proposed model fuel. The influence of ethanol as an oxygenated additive has been investigated for these two fuels and has been found to be negligible for values up to 15%(vol). Measurements were also performed for ethanol and the three pure components of the model fuel at 298, 358 and 398K. The results obtained for the studied mixtures, and for pure n-heptane, iso-octane, toluene and ethanol, have been satisfactorily simulated using a detailed kinetic mechanism.
Rapid Ultratough Topological Tissue Adhesives Cintron‐Cruz, Juan A.; Freedman, Benjamin R.; Lee, Matthew ...
Advanced materials (Weinheim),
September 1, 2022, 2022-Sep, 2022-09-00, 20220901, Letnik:
34, Številka:
35
Journal Article
Recenzirano
Tissue adhesives capable of achieving strong and tough adhesion in permeable wet environments are useful in many biomedical applications. However, adhesion generated through covalent bond formation ...directly with the functional groups of tissues (i.e., COOH and NH2 groups in collagen), or using non‐covalent interactions can both be limited by weak, unstable, or slow adhesion. Here, it is shown that by combining pH‐responsive bridging chitosan polymer chains and a tough hydrogel dissipative matrix one can achieve unprecedented ultratough adhesion to tissues (>2000 J m−2) in 5–10 min without covalent bond formation. The strong non‐covalent adhesion is shown to be stable under physiologically relevant conditions and strongly influenced by chitosan molecular weight, molecular weight of polymers in the matrix, and pH. The adhesion mechanism relies primarily on the topological entanglement between the chitosan chains and the permeable adherends. To further expand the applicability of the adhesives, adhesion time can be decreased by dehydrating the hydrogel matrix to facilitate rapid chitosan interpenetration and entanglement (>1000 J m−2 in ≤1 min). The unprecedented adhesive properties presented in this study open opportunities for new strategies in the development of non‐covalent tissue adhesives and numerous bioapplications.
Tissue adhesives capable of achieving tough adhesion in wet environments are useful in many biomedical applications. It is shown that combining pH‐responsive bridging chitosan polymer chains and a tough hydrogel dissipative matrix can achieve ultratough adhesion to tissues (>2000 J m−2) without covalent bond formation. These properties open opportunities for new strategies in the development of non‐covalent tissue adhesives.
The adsorption of Acid blue 25, basic blue 9, basic violet 3, Pb2+, Ni2+, Zn2+ and Cd2+ ions has been studied in single and dye–metal binary solutions using two mineral materials: Clinoptilolite (CL) ...and ER (Erionite). These zeolites were characterized by FT-IR spectroscopy; potentiometric titration and nitrogen adsorption isotherms at 77 K to obtain their textural parameters. Results indicated that ER has an acidic character and a high specific surface (401 m2 g−1) in contrast with the zeolite CL (21 m2 g−1). Surprisingly, the removal of dyes was very similar for the two zeolites and they showed a considerable selectivity by the basic dyes in comparison with the acid dyes. In the case of heavy metals, ER was more effective in the adsorption process showing a selectivity of: Pb2+ > Ni2+ > Zn2+ > Cd2+. In the multicomponent adsorption experiments an antagonistic effect was observed in the removal of basic dyes and heavy metals. Particularly, the adsorbed amount of basic violet 3 decreased more significantly when the heavy metals are presents in contrast with the basic blue 9.
► Adsorption of dyes and heavy metals was studied in single and dye–metal solutions. ► Two natural zeolites: Clinoptilolite and Erionite were used as sorbents. ► The zeolites are more efficient to remove cationic dyes. ► In dye–metal binary solutions one antagonistic effect was observed in the adsorption of dyes and heavy metals.
Asthma is a major cause of disability, health resource utilization and poor quality of life world-wide. We set out to generate estimates of the global burden of asthma in adults, which may inform the ...development of strategies to address this common disease.
The World Health Survey (WHS) was developed and implemented by the World Health Organization in 2002-2003. A total of 178,215 individuals from 70 countries aged 18 to 45 years responded to questions related to asthma and related symptoms. The prevalence of asthma was based on responses to questions relating to self-reported doctor diagnosed asthma, clinical/treated asthma, and wheezing in the last 12 months.
The global prevalence rates of doctor diagnosed asthma, clinical/treated asthma and wheezing in adults were 4.3%, 4.5%, and 8.6% respectively, and varied by as much as 21-fold amongst the 70 countries. Australia reported the highest rate of doctor diagnosed, clinical/treated asthma, and wheezing (21.0%, 21.5%, and 27.4%). Amongst those with clinical/treated asthma, almost 24% were current smokers, half reported wheezing, and 20% had never been treated for asthma.
This study provides a global estimate of the burden of asthma in adults, and suggests that asthma continues to be a major public health concern worldwide. The high prevalence of smoking remains a major barrier to combating the global burden of asthma. While the highest prevalence rates were observed in resource-rich countries, resource-poor nations were also significantly affected, posing a barrier to development as it stretches further the demands of non-communicable diseases.
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