Nanoclay-reinforced HA/alginate scaffolds as cell carriers and SDF-1 delivery-platforms for bone tissue engineering

Bone tissue engineering has come on the scene to overcome the difficulties of the current treatment strategies. By combining biomaterials, active agents and growth factors, cells and nanomaterials, tissue engineering makes it possible to create new structures that enhance bone regeneration. Herein, hyaluronic acid and alginate were used to create biologically active hydrogels, and montmorillonite nanoclay was used to reinforce and stabilize them. The developed scaffolds were found to be biocompatible and osteogenic with mMSCs in vitro, especially those reinforced with the nanoclay, and allowed mineralization even in the absence of differentiation media. Moreover, an in vivo investigation was performed to establish the potential of the hydrogels to mend bone and act as cell-carriers and delivery platforms for SDF-1. Scaffolds embedded with SDF-1 exhibited the highest percentages of bone regeneration as well as of angiogenesis, which confirms the suitability of the scaffolds for bone. Although there are a number of obstacles to triumph over, these bioengineered structures showed potential as future bone regeneration treatments

The Manufacture of Unbreakable Bionics via Multifunctional and Self-Healing Silk-Graphene Hydrogels

Biomaterials capable of transmitting signals over longer distances than those in rigid electronics can open new opportunities for humanity by mimicking the way tissues propagate information. For seamless mirroring of the human body, they also have to display conformability to its curvilinear architecture, as well as, reproducing native-like mechanical and electrical properties combined with the ability to self-heal on demand like native organs and tissues. Along these lines, a multifunctional composite is developed by mixing silk fibroin and reduced graphene oxide. The material is coined "CareGum" and capitalizes on a phenolic glue to facilitate sacrificial and hierarchical hydrogen bonds. The hierarchal bonding scheme gives rise to high mechanical toughness, record-breaking elongation capacity of approximate to 25 000%, excellent conformability to arbitrary and complex surfaces, 3D printability, a tenfold increase in electrical conductivity, and a fourfold increase in Young's modulus compared to its pristine counterpart. By taking advantage of these unique properties, a durable and self-healing bionic glove is developed for hand gesture sensing and sign translation. Indeed, CareGum is a new advanced material with promising applications in fields like cyborganics, bionics, soft robotics, human-machine interfaces, 3D-printed electronics, and flexible bioelectronics.Peer reviewe

A Protein-Based, Water-Insoluble, and Bendable Polymer with Ionic Conductivity: A Roadmap for Flexible and Green Electronics

Contains fulltext : 215371.pdf (publisher's version ) (Open Access)Proteins present an ecofriendly alternative to many of the synthetic components currently used in electronics. They can therefore in combination with flexibility and electroactivity uncover a range of new opportunities in the field of flexible and green electronics. In this study, silk-based ionic conductors are turned into stable thin films by embedding them with 2D nanoclay platelets. More specifically, this material is utilized to develop a flexible and ecofriendly motion-sensitive touchscreen device. The display-like sensor can readily transmit light, is easy to recycle and can monitor the motion of almost any part of the human body. It also displays a significantly lower sheet resistance during bending and stretching regimes than the values typically reported for conventional metallic-based conductors, and remains fully operational after mechanical endurance testing. Moreover, it can operate at high frequencies in the kilohertz (kHz) range under both normal and bending modes. Notably, our new technology is available through a simple one-step manufacturing technique and can therefore easily be extended to large-scale fabrication of electronic devices

Flexible Electronics: A Protein‐Based, Water‐Insoluble, and Bendable Polymer with Ionic Conductivity: A Roadmap for Flexible and Green Electronics (Adv. Sci. 5/2019)

Contains fulltext : 215371.pdf (publisher's version ) (Open Access)Proteins present an ecofriendly alternative to many of the synthetic components currently used in electronics. They can therefore in combination with flexibility and electroactivity uncover a range of new opportunities in the field of flexible and green electronics. In this study, silk-based ionic conductors are turned into stable thin films by embedding them with 2D nanoclay platelets. More specifically, this material is utilized to develop a flexible and ecofriendly motion-sensitive touchscreen device. The display-like sensor can readily transmit light, is easy to recycle and can monitor the motion of almost any part of the human body. It also displays a significantly lower sheet resistance during bending and stretching regimes than the values typically reported for conventional metallic-based conductors, and remains fully operational after mechanical endurance testing. Moreover, it can operate at high frequencies in the kilohertz (kHz) range under both normal and bending modes. Notably, our new technology is available through a simple one-step manufacturing technique and can therefore easily be extended to large-scale fabrication of electronic devices

Phytochemical-loaded mesoporous silica nanoparticles for nose-to-brain olfactory drug delivery

Central nervous system (CNS) drug delivery is often hampered due to the insidious nature of the blood-brain barrier (BBB). Nose-to-brain delivery via olfactory pathways have become a target of attention for drug delivery due to bypassing of the BBB. The antioxidant properties of phytochemicals make them promising as CNS active agents but possess poor water solubility and limited BBB penetration. The primary aim of this study was the development of mesoporous silica nanoparticles (MSNs) loaded with the poorly water-soluble phytochemicals curcumin and chrysin which could be utilised for nose-to-brain delivery. We formulated spherical MSNP using a templating approach resulting in ∼220nm particles with a high surface porosity. Curcumin and chrysin were successfully loaded into MSNP and confirmed through Fourier transformation infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and HPLC approaches with a loading of 11-14% for curcumin and chrysin. Release was pH dependant with curcumin demonstrating increased chemical stability at a lower pH (5.5) with a release of 53.2%±2.2% over 24h and 9.4±0.6% for chrysin. MSNP were demonstrated to be non-toxic to olfactory neuroblastoma cells OBGF400, with chrysin (100μM) demonstrating a decrease in cell viability to 58.2±8.5% and curcumin an IC50 of 33±0.18μM. Furthermore confocal microscopy demonstrated nanoparticles of <500nm were able to accumulate within cells with FITC-loaded MSNP showing membrane localised and cytoplasmic accumulation following a 2h incubation. MSNP are useful carriers for poorly soluble phytochemicals and provide a novel vehicle to target and deliver drugs into the CNS and bypass the BBB through olfactory drug delivery

Payday Loans in Finland and the USA : Contrasting Legal Responses to Consumer Indebtedness

The purpose of the thesis is to indicate issues regarding payday loans and how the new law reform will affect the over-indebtedness of youth in Finland. I have used secondary research material for this thesis. The topic has been relevant in the current economic environment and therefore the best sources are news outlets such as The New York Times, CNBC and Kauppalehti. Data for this thesis has also been gathered from articles, literature, Finnish legislation and payday creditors website. The law reform has prohibited high cost consumer credit loans in Finnish markets. The creditors are facing decreased return for their loans. As a result, the creditors can no longer grant loans to insolvent consumers. The consumer credit information will become more essential in the decision-making process of the creditor. Therefore, the debt cycle of the over indebted consumers will decline as they are not able to receive new loan to repay their prior debts. The law has been reformed in order to protect consumers from the predatory payday lenders. Based on the findings many payday lenders have quit their operations leading to a decreased supply of small short-term loans. The remaining payday lenders offer higher credit limit to consumers with longer payback period. The regulation could also have the opposite effect as the consumers are able to withdraw higher amount of loan with longer payback period. Prohibiting high cost loans will not solve the primary issue of the consumers

Venäjän ja Suomen LVI-määräysten vertailu

The aim of this master's thesis is to compare Finnish and Russian regulations and guidelines concerning HVAC systems. Based on extensive analysis of norms prevailing in both countries, the thesis provides a description of key differences between the Russian and Finnish codes. Special attention is paid to workplaces, which the Russian code treats as separate and different from other spaces. There are generally two types of indoor air design value: permissible and optinum, both of which are applied as a basis for designing certain classifications or systems. There are also two different values for outdoor air conditions, 'parameter A' and 'parameter B' for cold and warm seasons separately. There are more restrictions in the Russian norm for planning a common system for different premises or fire departments. The ventilation system has to he designed as natural ventilation, especially for residential premises, unless it is confirmed that a suitable indoor climate cannot be achieved with natural ventilation. External air must be supplied by powered ventilation to vestibules, air locks and some workplaces. Air heating must be planned for workplaces that operating more than 8 hours per day, and a reserve system must be planned and installed in some cases. Limits exist for maximum and minimum temperatures and maximum velocity of supply air jet, and these must be calculated using the formulas provided in the norm. Higher airflow rates are required for workplaces in the Russian norm. The required airflow rate for spaces in which unusual conditions prevail must be calculated using the procedures presented in the norm. The concentration levels of all extracted air are not to exceed the limits specified in the norm. Air extracted from workplaces must normally be filtrated. Filtration of supply air is not always required unless this is necessitated by the concentration limit of the supply air. The room air must usually be in balance, with the exception of certain premises. Air curtain units must be planned in some cases according to the Russian norm. There are further restrictions for installing different types of equipment in the same ventilation machine room. In the Russian norm, three different fire, air and return dampers are required for fire safety. On the whole, lower fire resistance is required in the Russian norm. Ducts have to be fire insulated also in their served zone. Emergency ventilation must be planned for some workplaces. There are precise and detailed procedures in the Russian norm for calculating all steps of the heating system. There is, however, no method for calculating the total energy demand of the building, so the calculations based on the Russian norm might result in a less economical heating system. There is only one method for calculating the smoke ventilation of all kinds of buildings. A mechanical or powered smoke ventilation system can be either automatically or manually activated according to the Russian norm. Natural smoke ventilation is allowed only for single-storey buildings in the Russian norm. The smoke flow to be removed from corridors is calculated to protect escape doors. Smoke exhaust terminal units are normally to be installed in corridors, halls and spaces without natural light

Simulation of Advance Thermal Processes in Buildings to Optimise Energy Performance and Costs

Defence is held on 17.12.2021 12:00 – 15:30 Zoom https://aalto.zoom.us/j/68812184033This study concentrates on methodologies and practical solutions to improve energy performance in indoor ice rink arenas and increase buildings' energy flexibility to reduce their energy costs. The objectives of the study are as follows: 1) to investigate how the temperature gradient impacts the heat load towards the ice pad and evaluate the effects of various air handling unit (AHU) layouts on energy consumption, particularly at the cooling coil section; 2) to develop a simplified calculation methodology/tool based on a steady-state analysis in order to roughly calculate the energy demands/costs and primary energy in such arenas; 3) to develop a price-based control approach for reducing the energy costs of a residential building equipped with an electric heater, a geothermal heat pump, a solar thermal collector and a thermal storage unit; and 4) to develop a qualitative control method based on both varying electricity prices and the predicted outdoor weather data. The control algorithm evaluates a building's energy needs for the next several hours with the aid of a weather forecast. The building performance simulation program, IDA Indoor Climate and Energy (IDA-ICE), was mainly conducted to obtain the results of ice rink arenas, and field measurements were implemented to validate the simulation models. The obtained simulation results were used to validate the calculator and determine its accuracy. The results of the control methods were also obtained by conducting a Transient System Simulation (TRNSYS) and simultaneously implementing the control algorithm into the simulation environment. The controllers' strategy was to forward or delay thermal and electricity loads in response to electricity price variations. The results reveal that ice rink refrigeration energy demand can be considerably decreased if the indoor temperature gradient approaches 1°C/m. To achieve this gradient, properly located and zoned air distribution solutions are proposed. Cooling and dehumidification energy demands reduced remarkably in the studied ice rink by 59.5% just by changing the location of the cooling coil in AHU. The applicability of the developed calculator is verified with reasonable accuracy in computing yearly energy costs, refrigeration and space heating demands and with a moderately higher deviation in cooling/dehumidification demands where a steady-state analysis is prone to considerable inaccuracy. According to the results of the price-based control method, the yearly cost of electricity can decrease considerably: in the studied case, by up to 11.6% by effectively shifting the loads, particularly during cold seasons. The qualitative control method reduces energy costs by 12.2%, which are further decreased by increasing the thermal storage capacity. Generally, the load-shifting concept can be applied as a potential benefit in any building. It should be noted that the price signal and its fluctuations, which may vary significantly in different countries, have aconsiderable impact on the attained cost reduction rate

In vitro and ex vivo modeling of enteric bacterial infections

ABSTRACTEnteric bacterial infections contribute substantially to global disease burden and mortality, particularly in the developing world. In vitro 2D monolayer cultures have provided critical insights into the fundamental virulence mechanisms of a multitude of pathogens, including Salmonella enterica serovars Typhimurium and Typhi, Vibrio cholerae, Shigella spp., Escherichia coli and Campylobacter jejuni, which have led to the identification of novel targets for antimicrobial therapy and vaccines. In recent years, the arsenal of experimental systems to study intestinal infections has been expanded by a multitude of more complex models, which have allowed to evaluate the effects of additional physiological and biological parameters on infectivity. Organoids recapitulate the cellular complexity of the human intestinal epithelium while 3D bioengineered scaffolds and microphysiological devices allow to emulate oxygen gradients, flow and peristalsis, as well as the formation and maintenance of stable and physiologically relevant microbial diversity. Additionally, advancements in ex vivo cultures and intravital imaging have opened new possibilities to study the effects of enteric pathogens on fluid secretion, barrier integrity and immune cell surveillance in the intact intestine. This review aims to present a balanced and updated overview of current intestinal in vitro and ex vivo methods for modeling of enteric bacterial infections. We conclude that the different paradigms are complements rather than replacements and their combined use promises to further our understanding of host-microbe interactions and their impacts on intestinal health