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The problem of vacant commercial premises has been present in some central areas of transitional cities of Central and Eastern Europe, which have decayed in parallel to spatially uneven urban development processes and/or suburban expansion. This research aims to contribute to systematic analysis of the reasons for abandonment of commercial premises in the centre of Zagreb and exploration of revitalisation strategies, with an emphasis on the significance of citizen participation for successful planning and management of the city. The research was undertaken in two phases in May, 2016. The first included mapping of vacant commercial premises on selected streets in Zagreb’s centre. Next, using a non-probabilistic sample, a questionnaire survey was carried out face-to-face and online (N = 200). The results of the questionnaire survey showed the respondents’ awareness of the complex set of reasons underlying the occurrence and expansion of this phenomenon in the city centre and the need for urban regeneration, including a stronger regulatory framework at the city level.

Mineralization of hydrogels is desirable prior to applications in bone regeneration. CaCO3 is a widely used bone regeneration material and Mg, when used as a component of calcium phosphate biomaterials, has promoted bone‐forming cell adhesion and proliferation and bone regeneration. In this study, gellan gum (GG) hydrogels were mineralized with carbonates containing different amounts of calcium (Ca) and magnesium (Mg) by alternate soaking in, firstly, a calcium and/or magnesium ion solution and, secondly, a carbonate ion solution. This alternate soaking cycle was repeated five times. Five different calcium and/or magnesium ion solutions, containing different molar ratios of Ca to Mg ranging from Mg‐free to Ca‐free were compared. Carbonate mineral formed in all sample groups subjected to the Ca:Mg elemental ratio in the carbonate mineral formed was higher than in the respective mineralizing solution. Mineral formed in the absence of Mg was predominantly CaCO3 in the form of a mixture of calcite and vaterite. Increasing the Mg content in the mineral formed led to the formation of magnesian calcite, decreased the total amount of the mineral formed and its crystallinity. Hydrogel mineralization and increasing Mg content in mineral formed did not obviously improve proliferation of MC3T3‐E1 osteoblast‐like cells or differentiation after 7 days.

Mineralization of hydrogel biomaterials is considered desirable to improve their suitability as materials for bone regeneration. Calcium carbonate (CaCO3) has been successfully applied as a bone regeneration material, but hydrogel‐CaCO3 composites have received less attention. Magnesium (Mg) has been used as a component of calcium phosphate biomaterials to stimulate bone‐forming cell adhesion and proliferation and bone regeneration in vivo, but its effect as a component of carbonate‐based biomaterials remains uninvestigated. In the present study, gellan gum (GG) hydrogels were mineralized enzymatically with CaCO3, Mg‐enriched CaCO3 and magnesium carbonate to generate composite biomaterials for bone regeneration. Hydrogels loaded with the enzyme urease were mineralized by incubation in mineralization media containing urea and different ratios of calcium and magnesium ions. Increasing the magnesium concentration decreased mineral crystallinity. At low magnesium concentrations calcite was formed, while at higher concentrations magnesian calcite was formed. Hydromagnesite (Mg5(CO3)4(OH)2.4H2O) formed at high magnesium concentration in the absence of calcium. The amount of mineral formed and compressive strength decreased with increasing magnesium concentration in the mineralization medium. The calcium:magnesium elemental ratio in the mineral formed was higher than in the respective mineralization media. Mineralization of hydrogels with calcite or magnesian calcite promoted adhesion and growth of osteoblast‐like cells. Hydrogels mineralized with hydromagnesite displayed higher cytotoxicity. In conclusion, enzymatic mineralization of GG hydrogels with CaCO3 in the form of calcite successfully reinforced hydrogels and promoted osteoblast‐like cell adhesion and growth, but magnesium enrichment had no definitive positive effect.

Mineralization of hydrogels is desirable prior to applications in bone regeneration. CaCO3 is a widely used bone regeneration material, and Mg, when used as a component of calcium phosphate biomaterials, has promoted bone-forming cell adhesion and proliferation and bone regeneration. In this study, gellan gum hydrogels were mineralized with carbonates containing different amounts of calcium (Ca) and magnesium (Mg) by alternate soaking in, firstly, a calcium and/or magnesium ion solution and, secondly, a carbonate ion solution. This alternate soaking cycle was repeated five times. Five different calcium and/or magnesium ion solutions, containing different molar ratios of Ca to Mg ranging from Mg free to Ca free were compared. Carbonate mineral formed in all sample groups subjected to the alternate soaking cycle. Ca : Mg elemental ratio in the mineral formed was higher than in the respective mineralizing solution. Mineral formed in the absence of Mg was predominantly CaCO3 in the form of a mixture of calcite and vaterite. Increasing the Mg content in the mineral formed led to the formation of magnesian calcite and decreased the total amount of the mineral formed and its crystallinity. Hydrogel mineralization and increasing Mg content in mineral formed did not obviously improve proliferation of MC3T3-E1 osteoblast-like cells or differentiation after 7 days.

Hydrogels offer several advantages as biomaterials for bone regeneration, including ease of incorporation of soluble substances such as mineralization-promoting enzymes and antibacterial agents. Mineralization with calcium phosphate (CaP) increases bioactivity, while antibacterial activity reduces the risk of infection. Here, gellan gum (GG) hydrogels were enriched with alkaline phosphatase (ALP) and/or Seanol(®), a seaweed extract rich in phlorotannins (brown algae-derived polyphenols), to induce mineralization with CaP and increase antibacterial activity, respectively. The sample groups were unmineralized hydrogels, denoted as GG, GG/ALP, GG/Seanol and GG/Seanol/ALP, and hydrogels incubated in mineralization medium (0.1 M calcium glycerophosphate), denoted as GG/ALP_min, GG/Seanol_min and GG/Seanol/ALP_min. Seanol(®) enhanced mineralization with CaP and also increased compressive modulus. Seanol(®) and ALP interacted in a non-covalent manner. Release of Seanol(®) occurred in a burst phase and was impeded by ALP-mediated mineralization. Groups GG/Seanol and GG/ALP/Seanol exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus. GG/Seanol/ALP_min, but not GG/Seanol_min, retained some antibacterial activity. Eluates taken from groups GG/ALP_min, GG/Seanol_min and GG/ALP/Seanol_min displayed comparable cytotoxicity towards MG-63 osteoblast-like cells. These results suggest that enrichment of hydrogel biomaterials with phlorotannin-rich extracts is a promising strategy to increase mineralizability and antibacterial activity.

Prisutnost turističkih poduzeća na društvenim mrežama biti će u sljedećih nekoliko godina od presudne važnosti u načinu ophođenja i komunikacije sa posjetiteljima. Posljednjih godina sve je više turističkih poduzeća i voditelja turističkih odredišta koji su prihvatili i razumjeli širenje društvenih mreža kao pozitivan iskorak u poslovanju i komunikaciji sa postojećim i potencijalnim posjetiteljima. Društvene mreže također su po tko zna koji put ponovo podsjetile da je posjetitelj u glavnom fokusu pažnje. Digitalno poslovanje i društvene mreže omogućavaju direktnu komunikaciju i reakciju sa posjetiteljima odredišta. Rezultat toga je sve veći fokus na komunikaciju i pristup kupcima putem izgradnje vlastite prepoznatljive marke. Proces definiranja odredišta nije jednostavan. Marka se danas više ne gradi jednostavnim prikazivanjem logotipa ili fotografije. Danas većina potencijalnih posjetitelja svoja nova odredišta traži na pretraživačima poput Googla, TripAdvisora i sl. Pretraživači u naravi omogućavaju potencijalnim posjetiteljima jednostavniji pristup putem stranica ili profila na društvenim mrežama do odredišta za odmor i uživanje, bolju informiranost te lakšu komunikaciju.

Hydrogels offer several advantages as biomaterials for bone regeneration, including ease of incorporation of soluble substances such as mineralization-promoting enzymes and antibacterial agents. Mineralization with calcium phosphate (CaP) increases bioactivity, while antibacterial activity reduces the risk of infection. Here, gellan gum (GG) hydrogels were enriched with alkaline phosphatase (ALP) and/or Seanol®, a seaweed extract rich in phlorotannins (brown algae-derived polyphenols), to induce mineralization with CaP and increase antibacterial activity, respectively. The sample groups were unmineralized hydrogels, denoted as GG, GG/ALP, GG/Seanol and GG/Seanol/ALP, and hydrogels incubated in mineralization medium (0.1 M calcium glycerophosphate), denoted as GG/ALP-min, GG/Seanol-min and GG/Seanol/ALP-min. Seanol® enhanced mineralization with CaP and also increased compressive modulus. Seanol® and ALP interacted in a non-covalent manner. Release of Seanol® occurred in a burst phase and was impeded by ALP-mediated mineralization. Groups GG/Seanol and GG/ALP/Seanol exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus. GG/Seanol/ALP-min, but not GG/Seanol-min, retained some antibacterial activity. Eluates taken from groups GG/ALP-min, GG/Seanol-min and GG/ALP/Seanol-min displayed comparable cytotoxicity towards MG-63 osteoblast-like cells. These results suggest that enrichment of hydrogel biomaterials with phlorotannin-rich extracts is a promising strategy to increase mineralizability and antibacterial activity.

P5CSF129A cDNA and the npt II marker gene were used for tobacco ( Nicotiana tabacum L. cv. Bel B and cv. M51) transformation via Agrobacterium tumefaciens strain LBA4404. Twenty transformed tobacco plants were obtained after transformation of leaf discs. Presence of the transgene was confirmed by polymerase chain reaction (PCR) analysis. Physiological responses to water stress were compared in transgenic and wild-type tobacco plants. Transgenic plants of both cultivars accumulated high levels of free proline. They did not exhibit dry mass relocation or chlorophyll content reduction. Neither precocious senescence, nor leaf necrosis or morphological changes were observed in control and stress conditions (RWC decrease by 7–8%). Transgenic plants with elevated accumulation of osmoprotectants seem to be better adapted to water stress, providing a perspective for future research of stress effects that have a principle role in the functional activity of plants. This study confirmed P5CSF129A to be a candidate gene in crop engineering for enhanced water stress tolerance.

An LPG-based auxiliary power unit (APU) is currently being developed at the Centre for Fuel Cell Technology (ZBT). Due to the modular design of the APU, the reformer/burner module and the CO purification module, combined in the mobile gas processor (MGP), and the low temperature PEM fuel cell (PEM FC) can be developed and characterized simultaneously. While the separate characterizations of the MGP and the PEM FC are satisfactory during the initial coupling tests, a condensation problem occurs in the PEM FC, because of the high water content in the reformate gas. This paper presents two possible solutions for the prevention of condensation inside the PEM FC, when coupled with a gas processor. Analogous testing is carried out by supplying synthesized reformate gas to the PEM FC, resulting in a 360 W maximum electrical power output at 85 °C. New membrane electrode assemblies (MEAs), which are suitable for reformate gas operation at temperatures up to 90 °C, are integrated in this PEM FC. Furthermore, the impact of CO on PEM FC performance can be minimized by adding an airbleed of 1.0 mol-% of the complete anode gas. Thus, stable operation is achieved with the separate PEM FC, by supplying a synthesized anode gas, which includes a CO concentration constantly between 30 and 50 ppm. The coupling of the MGP with the PEM FC, under the improved operating conditions, leads to an electrical power output of 351 W. The overall APU efficiency is 28.5%.

Republika Hrvatska opredijelila se za održivi razvoj kao politiku razvitka hrvatskih otoka. Glavni problemi hrvatskih otoka danas su depopulacija i degradacija autohtonih kulturnih i arhitektonskih vrijednosti koja posljedično dovodi do nestajanja mediteranskog otočnog identiteta. S obzirom na resursnu osnovu, prirodnu i kulturnu raznolikost i očuvani okoliš, otoci imaju preduvjete za razvijanje ekološke poljoprivrede i agroturizma kao komplementarnih djelatnosti. Kao jedan od uspješnijih primjera sprege poljoprivredne proizvodnje i turizma analiziran je otok Rab. Analizom je ustanovljeno da bi funkcionalno povezivanje poljoprivrede i turizma u okviru agroturizma doprinijelo racionalnijem vrednovanju postojećih prirodnih resursa, s dugoročno pozitivnim učincima na sve komponente održivog razvoja, odnosno stabilizaciju naseljenosti na otocima. The Republic of Croatia committed itself to sustainable development as a policy of development of the Croatian islands. Main problems of the Croatian islands are depopulation and degradation of indigenous cultural and architectural values which consequently leads to the disappearance of the Mediterranean island's identity. Due to resource base, natural and cultural diversity and preserved environment, islands have preconditions for the development of organic farming and agro-tourism as a complementary activity. As one of the most successful example of collusion between agriculture and tourism was analyzed Rab. The analysis established that the functional linkage between agriculture and tourism in the framework of agro-tourism contributed to rational evaluation of the existing natural resources, with a long-term positive effects on all components of sustainable development and stabilization of the population on the islands.

Introduction: Mineralization of hydrogel biomaterials is considered desirable to improve their suitability as materials for bone regeneration[1],[2]. Hydrogels have been most commonly mineralized with calcium phosphate (CaP), but hydrogel-CaCO3 composites have received less attention. Magnesium (Mg) has been added to CaP to stimulate cell adhesion and proliferation and bone regeneration in vivo, but its effect as a component of carbonate-based biomaterials remains uninvestigated. In this study, gellan gum (GG) hydrogels were mineralized enzymatically with (CaCO3), Mg-enriched CaCO3 and magnesium carbonate to generate composite biomaterials for bone regeneration. GG is an inexpensive, biotechnologically produced anionic polysaccharide, from which hydrogels for cartilage regeneration have been formed by crosslinking with divalent ions[3].Methods: GG hydrogels were loaded with the enzyme urease by incubation in 5% (w/v) urease solution and mineralized for 5 days in five different media denoted as UA, UB, UC, UD and UE, which contained urea (0.17 M) and different concentrations of CaCl2 and MgCl2 (270:0, 202.5:67.5, 135:135, 67.5:202.5 and 0:250, respectively (mmol dm-3)). Discs were autoclaved and subjected to physiochemical, mechanical and cell biological characterization.Results: FTIR, SEM, TGA and XRD analysis revealed that increasing magnesium concentration decreased mineral crystallinity. At low magnesium concentrations calcite was formed, while at higher concentrations magnesian calcite was formed. Hydromagnesite formed at high magnesium concentration in the absence of calcium. Amount of mineral formed and compressive strength decreased with increasing magnesium concentration in the mineralization medium. ICP analysis revealed that Ca:Mg elemental ratio in the mineral formed was higher than in the respective mineralization media. Mineralization of hydrogels promoted adhesion and growth of osteoblast-like cells, which were supported best on mineralized hydrogels containing no or little magnesium. Hydrogels mineralized with hydromagnesite displayed higher cytotoxicity.Discussion: Enzymatic mineralization of GG hydrogels with CaCO3 in the form of calcite successfully reinforced hydrogels and promoted osteoblast-like cell adhesion and growth, but Mg enrichment had no positive effect. This is in contrast with other studies reporting that incorporation of Mg into GG mineralized with CaP promotes cell adhesion and proliferation[4]. Conclusion: Sample groups UA and UB seem to be the most promising due to the superior amount of mineral formed and cell adhesion and proliferation.

With focus on mobile applications a fuel cell auxiliary power unit (APU) using liquefied petroleum gas (LPG) is currently being developed at the Centre for Fuel Cell Technology (Zentrum fur BrennstoffzellenTechnik, ZBT gGmbH). The system is consisting of an integrated compact and lightweight fuel processor and a low temperature PEM fuel cell for an electric power output of 300 W. This article is presenting the current status of development of the fuel processor which is designed for a nominal hydrogen output of 1 k W th , H 2 within a load range from 50 to 120%. A modular setup was chosen defining a reformer/burner module and a CO-purification module. Based on the performance specifications, thermodynamic simulations, benchmarking and selection of catalysts the modules have been developed and characterised simultaneously and then assembled to the complete fuel processor. Automated operation results in a cold startup time of about 25 min for nominal load and carbon monoxide output concentrations below 50 ppm for steady state and dynamic operation. Also fast transient response of the fuel processor at load changes with low fluctuations of the reformate gas composition have been achieved. Beside the development of the main reactors the transfer of the fuel processor to an autonomous system is of major concern. Hence, concepts for packaging have been developed resulting in a volume of 7 l and a weight of 3 kg. Further a selection of peripheral components has been tested and evaluated regarding to the substitution of the laboratory equipment.

At the Centre for Fuel Cell Technology (Zentrum fur BrennstoffzellenTechnik/ZBT GmbH) in Duisburg/Germany a 300 W fuel cell system of liquid gas-powered operation is currently being developed with focus on leisure boats. An excellent infrastructure in the domain of recreational activities is available for this fuel and users are familiar with the safe handling of liquid gas. On sailing yachts the consumption of electrical power is very restricted during long cruises because of low battery capacities. In this case an additional power supply based on the noiseless fuel cell technology promises an essential comfort increase without disturbing emissions. ZBT's engineers combined their experience in system simulation, reactor design for the gas process and fuel cell technology with the aim of developing a user friendly fuel cell product.

Recently, highly sensitive strain gauges were developed, which are based on tunnel magnetoresistance (TMR) or giant magnetoresistance (GMR) effects combined with the inverse magnetostriction. GMR and TMR structures generally possess a symmetrical characteristic, which reflects the switching fields of the soft and hard layers, respectively. This characteristic can be changed by a stress field if the soft layer is replaced by a suitable magnetostrictive layer leading to a stress-induced rotation of the magnetostrictive layer with respect to the reference layer. Alternatively, both magnetic layers can be soft magnetic, one being positive and the other negative magnetostrictive. In this case, a stress applied on the stack leads to a reverse rotation of both layers due to the different sign in magnetostriction. This new approach is especially attractive since no reference layer is required which allows multilayering for GMR effect enhancement. This paper presents the stress biased characteristics of (FeCo/Cu/Ni) GMR trilayers in which the positive magnetostrictive FeCo and the negative magnetostrictive Ni replace the sensing and reference layer of a conventional GMR stack. The results can be interpreted by a simple model taking into account the magnetization direction of the individual layers and their response to mechanical strain in the range of 0.1–1‰.

Background: There appears little consensus concerning protein requirements in phenylketonuria (PKU). Methods: A questionnaire completed by 63 European and Turkish IMD centres from 18 countries collected data on prescribed total protein intake (natural/intact protein and phenylalanine-free protein substitute [PS]) by age, administration frequency and method, monitoring, and type of protein substitute. Data were analysed by European region using descriptive statistics. Results: The amount of total protein (from PS and natural/intact protein) varied according to the European region. Higher median amounts of total protein were prescribed in infants and children in Northern Europe (n = 24 centres) (infants 2-3 g/kg/day; 1-3 years of age, >2-3 g/kg/day; 4-10 years of age, >1.5-2.5 g/kg/day) and Southern Europe (n = 10 centres) (infants 2-2.5 g/kg/day; 4-10 years of age, >1.5-2 g/kg/day) and with Western Europe (n = 25 centres) giving the least (infants 2-2.5 g/kg/day, 1-3 years of age, 1.5-2 g/kg/day; 4-10 years of age, 1-1.5 g/kg/day). Total protein prescription was similar in patients aged >10 years (1-1.5 g/kg/day) and maternal patients (1-1.5 g/kg/day). Conclusions: The amounts of total protein prescribed varied between European countries and appeared to be influenced by geographical region. In PKU, all gave higher than the recommended 2007 WHO/FAO/UNU safe levels of protein intake for the general population. (C) 2015 Elsevier Inc. All rights reserved.

Item does not contain fulltext Hydrogels of biocompatible calcium-crosslinkable polysaccharide gellan gum (GG) were enriched with bioglass particles to enhance (i) mineralization with calcium phosphate (CaP); (ii) antibacterial properties and (iii) growth of bone-forming cells for future bone regeneration applications. Three bioglasses were compared, namely one calcium-rich and one calcium-poor preparation both produced by a sol-gel technique (hereafter referred to as A2 and S2, respectively) and one preparation of composition close to that of the commonly used 45S5 type (hereafter referred to as NBG). Incubation in SBF for 7 d, 14 d and 21 d caused apatite formation in bioglass-containing but not in bioglass-free samples, as confirmed by FTIR, XRD, SEM, ICP-OES, and measurements of dry mass, i.e. mass attributable to polymer and mineral and not water. Mechanical testing revealed an increase in compressive modulus in samples containing S2 and NBG but not A2. Antibacterial testing using biofilm-forming meticillin-resistant staphylococcus aureus (MRSA) showed markedly higher antibacterial activity of samples containing A2 and S2 than samples containing NBG and bioglass-free samples. Cell biological characterization using rat mesenchymal stem cells (rMSCs) revealed a stimulatory effect of NBG on rMSC differentiation. The addition of bioglass thus promotes GG mineralizability and, depending on bioglass type, antibacterial properties and rMSC differentiation.

Magnetostrictive tunneling magnetoresistive (TMR) pressure sensors have been developed by combining micro electrical–mechanical systems (MEMS) fabrication techniques with magnetic thin film technology. The sensing TMR elements with magnetostrictive Fe 50 Co 50 free layers were placed on different positions on a 2-μm-thick Si membrane structure allowing localized strain measurements. Compressive or tensile mechanical strain up to 0.12% can be introduced by applying different air pressure (0.1–4 bar) to the sealed membrane cavity, which in turn leads to a change in the magnetization direction due to the inverse magnetostrictive effect. For the first time, the strain-induced switching of the free layers has been characterized by means of magneto-optical Kerr effect (MOKE) measurements.

Hydrogels offer several advantages as biomaterials for bone regeneration, including ease of incorporation of soluble substances such as mineralization-promoting enzymes and antibacterial agents. Mineralization with calcium phosphate (CaP) increases bioactivity, while antibacterial activity reduces the risk of infection. Here, gellan gum (GG) hydrogels were enriched with alkaline phosphatase (ALP) and/or Seanol(®), a seaweed extract rich in phlorotannins (brown algae-derived polyphenols), to induce mineralization with CaP and increase antibacterial activity, respectively. The sample groups were unmineralized hydrogels, denoted as GG, GG/ALP, GG/Seanol and GG/Seanol/ALP, and hydrogels incubated in mineralization medium (0.1 M calcium glycerophosphate), denoted as GG/ALP_min, GG/Seanol_min and GG/Seanol/ALP_min. Seanol(®) enhanced mineralization with CaP and also increased compressive modulus. Seanol(®) and ALP interacted in a non-covalent manner. Release of Seanol(®) occurred in a burst phase and was impeded by ALP-mediated mineralization. Groups GG/Seanol and GG/ALP/Seanol exhibited antibacterial activity against methicillin-resistant Staphylococcus aureus. GG/Seanol/ALP_min, but not GG/Seanol_min, retained some antibacterial activity. Eluates taken from groups GG/ALP_min, GG/Seanol_min and GG/ALP/Seanol_min displayed comparable cytotoxicity towards MG-63 osteoblast-like cells. These results suggest that enrichment of hydrogel biomaterials with phlorotannin-rich extracts is a promising strategy to increase mineralizability and antibacterial activity.

In the paper results of low frequency noise measurements of SiC MESFET transistors were presented. The investigations were carried out on MESFET type CRF24010 (CREE). The low frequency noise of drain current and of gate current was measured in two-channel system, separately but in the same time. The spectra of a drain current noise and of a gate current noise were evaluated, also a coefficient of coherence between these noise sources. The noise of gate current was measured in the one-channel system. The noise model of MESFET for CRF24010 transistors for low frequency was elaborated.

In the paper a new method of Random Telegraph Signal (RTS) noise identification is presented. The method is based on a standardized histogram of i nstantaneous noise values and processing by Gram-Charlier series. To find a device generating RTS noise by the presented method one should count t he number of significant coefficients of the Gram- Charlier series. This would allow to recognize the t ype of noise. There is always one (first) significant coefficient ( c0) representing Gaussian noise. If additional coefficients cr (where r > 0) appear it means that RTS noise (two-level as well as multiple- level) is detected. The coefficient representing the Gaussian component always has the h ighest value of all. The application of this method will be presented on the example of four devices, each with di fferent noise (pure Gaussian noise signal, noise signal with two-level RTS noise, noise signal with three- level RTS noise and noise signal with not precisely visible occurrence of RTS noise). K eywords: RTS noise, Gram-Charlier series, semiconductor devices, optocouplers.