Molecular platforms for targeted drug delivery

The targeted delivery of bioactive molecules to the appropriate site of action, one of the critical focuses of pharmaceutical research, improves therapeutic outcomes and increases safety at the same time; a concept envisaged by Ehrlich over 100 years ago when he described the "magic bullet" model. In the following decades, a considerable amount of research effort combined with enormous investment has carried selective drug targeting into clinical practice via the advent of monoclonal antibodies (mAbs) and antibody-drug conjugates derivatives. Additionally, a deeper understanding of physiopathological conditions of disease has permitted the tailored design of targeted drug delivery platforms that carry drugs, many copies of the same drug, and different drugs in combination to the appropriate site of action least selectively or preferentially. The acquired know-how has provided the field with the design rationale to develop a successful delivery system that will provide new and improved means to treat many intractable diseases and disorders. In this review, we discuss a wide range of molecular platforms for drug delivery, and focus on those with more success in the clinic, given their potential for targeted therapies

Determining diode parameters of illuminated current density-voltage curves considering the voltage-dependent photo current density

Suitable procedures for the determination of diode parameters of illuminated and dark current density-voltage (j-V) curves of solar cells are investigated. Within these procedures we avoid misinterpretations by the commonly used shifting approximation which assumes a voltage-independent photo carrier collection. To this end, the voltage-dependent collection efficiency is determined by j-V measurements under incremental illumination. After that, illuminated curves can be converted into dark curves taking the voltage-dependent photo current density into account. The converted dark curve next is consigned into a program that numerically solves the implicit equation of the current density and derives the diode parameters by means of a weighted least-squares minimization. Only if fluctuations of the illumination are noticeably high this procedure cannot be used, since the converted dark curve also reveals a high noise level. Then, the determination of diode parameters is performed stepwise with the help of commonly used methods

Thermodynamic interaction of some mono and dichloroalkanes with cyclohexane

The heats of mixing of cyclohexane with 3-chloropentane, 2-chloro-2-methylbutane and 1,3-dichlorobutane at 25 °C were measured by means of a Tian-Calvet microcalorimeter; their dependence on composition was correlated by using Redlich-Kister’s equation. The system of equations for calculating the parameters of Barker’s theory is presented in the matrix form. The equilibrium constant and the energy of formation of the contact chlorine (Cl)-cycloparaflinic methylene group (C) were calculated from experimental results and some literary data.The necessary parameters of the contact between C and the aliphatic groups (R) were determined from the literary data of the system cyclohexane — heptane ; the parameters of the contact R-Cl were calculated from the literary data of the systems 1-chlorobutane — heptane and 1,3-dichloropropane- heptane. The equilibrium constants of the formation of contacts were calculated separately from the activity data (if available) and — along with the energies of contacts — from the energies of mixing by minimalizing departures of the calculated course from the experimental one. The final energy values of the C-Cl contacts are lower for 1,3-dichloro-butane than for monochloro derivatives; this is in accord with the results of Grolier and Kehiaian for mixtures of mono- and dichloro alkanes with heptane

Optimal PVB System Sizing and Energy Management for Grid-Connected Households

Due to the increasingly dominant climate change, "green"energy sources that do not contribute to further damage of the environment play an emerging and relevant role. A big advantage is that this kind of energy can be generated not only on a large scale, such as by wind turbines or hydroelectric power plants, but also by individual households through (among others) so-called Photovoltaic-Battery (PVB) systems which are based on solar energy. Compared with energy from the power grid, such systems naturally involve higher acquisition costs, which can, however, potentially be amortized. This raises the question of how large such systems should be designed, what the optimal strategy of usage is, and how relevant typical sizes of the individual elements available on the market are to the design strategy. Against this background, we investigate the problems addressed, taking into account different pricing strategies, and show, based on a simulation study, that PVB systems can bring major benefits in the long term. Additionally, our results indicate, that - to a certain extent - efficient energy management is able to compensate for limitations in sizing

Metastability of solar cells based on evaporated chalcopyrite absorber layers prepared with varying selenium flux

Solar cells with Cu In,Ga Se2 absorber layers prepared by three stage co evaporation with varying seleniumto metal flux ratio were studied in terms of their metastable properties. In particular, transient behaviour of the open circuit voltage Voc after relaxation to the stable state was investigated. A linear dependence of Voc on a logarithmic time scale was observed, the slope of which is taken as ameasure for the degree ofmetastability. Surprisingly, upon variation of selenium flux, the slope parameter systematically varies between negative and positive values, and there are process parameters, for which the Voc transient disappears. We discuss these findings within the framework of the well known Lany Zunger mode

Development of a customisable 3D-printed intra-oral stent for head-and-neck radiotherapy

Intra-oral stents (including mouth-pieces and bite blocks) can be used to displace adjacent non-involved oral tissue and reduce radiation side effects from radiotherapy treatments for head-and-neck cancer. In this study, a modular and customisable 3D printed intra-oral stent was designed, fabricated and evaluated, to utilise the advantages of the 3D printing process without the interruption of clinical workflow associated with printing time. The stent design used a central mouth-opening and tongue-depressing main piece, with optional cheek displacement pieces in three different sizes, plus an anchor point for moulding silicone to fit individual patients’ teeth. A magnetic resonance imaging (MRI) study of one healthy participant demonstrated the tissue displacement effects of the stent, while providing a best-case indication of its comfort.</p