Hydroxyapatite (HAp) and bacterial cellulose (BC) composite materials represent a promising approach for tissue engineering due to their excellent biocompatibility and bioactivity. This paper presents the synthesis and characterization of two types of materials based on HAp and BC, with antibacterial properties provided by silver nanoparticles (AgNPs). The composite materials were obtained following two routes: (1) HAp was obtained in situ directly in the BC matrix containing different amounts of AgNPs by the coprecipitation method, and (2) HAp was first obtained separately using the coprecipitation method, then combined with BC containing different amounts of AgNPs by ultrasound exposure. The obtained materials were characterized by means of XRD, SEM, and FT-IR, while their antimicrobial effect was evaluated against Gram-negative bacteria (Escherichia coli), Gram-positive bacteria (Staphylococcus aureus), and yeast (Candida albicans). The results demonstrated that the obtained composite materials were characterized by a homogenous porous structure and high water absorption capacity (more than 1000% w/w). These materials also possessed low degradation rates (<5% in simulated body fluid (SBF) at 37 °C) and considerable antimicrobial effect due to silver nanoparticles (10–70 nm) embedded in the polymer matrix. These properties could be finetuned by adjusting the content of AgNPs and the synthesis route. The samples prepared using the in situ route had a wider porosity range and better homogeneity.

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~~~~s~~a d t~~~~p~~, s .~~~~~a d t~~~~p~~~% . _ r r ? , ~~.Y@&~.P-u~LQ AbstractContinuing component dimension shrinking, associated with the dramatically increase of the operating @equenq, require an improved modelling of the interconnection to include coupled electromagnetic and thermal effects. Among these, skin and proximity effects are essential in the thermal management of thepackoge. Many electronic packages use as main signals, periodic sequence of rectangularpulses. Infirst part of this paper the influence of skin andproximity effects on the interconnection resistance when the current is a periodic sequence of rectangular pulses is reported. The non-sinusoidal skin effect is traditionally analysed by Fourier harmonic series. However slow convergent electromagnetic power series results. Series with accelerated convergence are used. These series are obtained by using a time-domain approach somehow similar to the transient analysis. Based on the non-sinusoidal skin depth concept. in the second part, it is presented a model for the evaluation of the increase factor of the resistance per unit length of the inferconnection structures for the pulse duration /pulse repetition period ratio in the range 0.1 to 0.5. Due to the higher harmonic content of this non-sinusoidal wave form the skin depth decreases significantly compared with sinusoidal one especially for large durations of the pause between two comemtivepulses. This paper focuses to o better understanding of the higher frequency effects in modem interconnection techniques. This novel approach allows the optimization of the interconnection structures.