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Abstract Freshwater macroinvertebrates are a diverse group and play key ecological roles, including accelerating nutrient cycling, filtering water, controlling primary producers, and providing food for predators. Their differences in tolerances and short generation times manifest in rapid community responses to change. Macroinvertebrate community composition is an indicator of water quality. In Europe, efforts to improve water quality following environmental legislation, primarily starting in the 1980s, may have driven a recovery of macroinvertebrate communities. Towards understanding temporal and spatial variation of these organisms, we compiled the TREAM dataset (Time seRies of European freshwAter Macroinvertebrates), consisting of macroinvertebrate community time series from 1,816 river and stream sites (mean length of 19.2 years and 14.9 sampling years) of 22 European countries sampled between 1968 and 2020. In total, the data include >93 million sampled individuals of 2,648 taxa from 959 genera and 212 families. These data can be used to test questions ranging from identifying drivers of the population dynamics of specific taxa to assessing the success of legislative and management restoration efforts.

Surface biophysical properties of biomaterials, including surface topography and roughness, determine the interaction of a biomaterial with the surrounding cells, tissues and organs once implanted in the human body. Herein, the surface topography of thermoplastic copolymers based on lactide and caprolactone showing elastomeric behaviour was modulated by precisely controlling the chain microstructure (i.e., distribution and length of the repetitive units within the polymeric chain). The synthesized copolymers were subjected to different thermal treatments from the melt, leading to polymeric films with various surface textures and roughness values. Copolymers synthesized with triphenyl bismuth as a catalyst, with a more random distribution of the repetitive units, showed limited crystallization capability. Accordingly, only the copolymer with higher amount of l-lactide (i.e., 80 wt%) subjected to an isothermal treatment from the melt at 70 °C was able to crystallize, and spherulites of around 7 μm were discernible by atomic force microscopy. In contrast, the copolymers synthesized with stannous octoate, which had a more blocky nature, showed axialitic crystalline domains at the submicron-to nanoscale when subjected to an isothermal treatment from the melt at 50 °C, whereas well-defined spherulites of sizes up to 14 μm were obtained at 70 °C. Human fibroblast showed a more elongated morphology when seeded on those samples having higher roughness values and larger spherulites, whereas they had a more spread morphology when seeded on the amorphous, smooth surfaces. As concluded from the present study, by precisely controlling the chain microstructure of the synthesized copolymers, a wide variety of surface topographies can be obtained, which has a clear impact on the way the biomaterial interacts with cells. This opens the possibility to study the influence of surface biophysical properties on more complex cell processes in the future, including inflammatory or foreign body response processes.

River ecosystems host a large biodiversity and provide essential ecosystem services but are threatened by multiple anthropogenic activities that degrade their structure and functioning. Although both structure and functioning are key components of ecological status, river monitoring programmes rely almost exclusively on structural indicators, such as community structure, or water quality, neglecting functional attributes. Scientists have pointed towards some promising functions, such as organic matter decomposition, as potential indicators of river functional status. However, it may not be the best indicator to assess the ecosystem functioning of river ecosystem subjected to certain impacts, such as nutrient inputs. Additionally, managers have seldom used functional indicators, probably because of the lack of simple, routine protocols. Here we present the nutrient uptake bioassay (NUB), a simple and straightforward method to measure nutrient uptake by river biofilm that could be developed as a functional indicator of river ecological status. The NUB consists in deploying biofilm carriers in the river for a specific period, allowing biofilm colonization. Biofilm carriers are then incubated in the field in a nutrient-enriched standard solution for one hour and finally the remaining nutrient concentration in the standard medium is measured. Nutrient uptake is calculated from the difference between the initial and final nutrient concentrations. Chlorophyll in the biofilm carriers can also be measured to calculate biofilm accrual rates. The NUB has been developed based on a mesocosm and a field experiments, which showed that the NUB provides additional, non-redundant information to current biomonitoring techniques. Overall, the NUB is a cheap, robust and reliable method that can be applied by most river monitoring practitioners and can be adapted to most river types and situations. As nutrient uptake is linked to the self-purification capacity of rivers, the NUB results provide information about an important ecosystem service. Therefore, we suggest that the NUB can be developed as part of the monitoring toolbox available for managers to improve the assessment of river ecological status and to diagnose the causes of ecosystem impairment.

The aim of this work is to evaluate the potential use of ashes and lapilli that buried Pompeii as pozzolanic material for the formulation of conservation mortars. XRD analyses proved that the mineralogical composition of these volcanic products is consistent with the original pozzolanic mortars preserved at the archaeological site. A first set of pozzolanic mortars were prepared by using silica sand as aggregate. After curing the lapilli-based mortars, the measured compressive and flexural strengths proved to be higher than those of the control samples made of commercial pozzolan. A second set of samples, prepared by replacing silica sand with similar size coarse ash and lapilli, proved that volcanic aggregates further enhanced the mechanical properties by the formation of interfacial transition zones. The result of this research demonstrates that the volcanic material burying the archaeological site of Pompeii could be used as raw material in the formulation of compatible conservation mortars. As volcanic pozzolan is increasingly investigated as potential Supplementary Cementitious Material (SCM) for the production of sustainable concretes, preliminary considerations about the impact of the present work to this field of research are also provided.

In this article, it is intended to evaluate the performances of previously synthesized different nanometric compounds as SOFC components under real conditions. For this purpose, anodic supports SOFCs have been manufactured in different configurations.The compounds NiO-(Y2O3)0.08(ZrO2)0.92 (NiO–YSZ), (Y2O3)0.08(ZrO2)0.92 (YSZ), Sm0.2Ce0.8O1.9 (SDC), La0.6Sr0.4FeO3 (LSF) and LaNi0.6Fe0.4O3 (LNF) were used as anode support, electrolyte, barrier, cathode and contact layer, respectively. To obtain the cells, the anode supports were produced by uniaxial pressing and the remaining layers were added using the airbrush technique, assembling them by different sintering processes. The cells developed have been electrochemically tested in a temperature range between 750 and 865 °C. Additionally, degradation tests have been carried out under constant current. Moreover, to characterize the microstructure of the cells, a scanning electron microscope (SEM) equipped with an energy dispersive X-ray spectroscopy (EDX) analyzer has been used.The results obtained show that the incorporation of cathode and contact layers increases the power densities and decreases the total resistances of the cells with respect to the cell without cathode, especially with the addition of the LNF contact layer. Despite the improvement obtained, more tests have to be carried out in order to optimize the performance of SOFC devices in degradation tests. Resumen: En el presente artículo se pretende evaluar el rendimiento de diferentes compuestos nanométricos previamente sintetizados como componentes pila de combustible de óxido sólido (SOFC) en condiciones reales. Para ello se han fabricado pilas SOFC de soporte anódico con distintas configuraciones.Los compuestos NiO-(Y2O3)0.08(ZrO2)0.92 (NiO–YSZ), (Y2O3)0.08(ZrO2)0.92 (YSZ), Sm0.2Ce0.8O1.9 (SDC), La0.6Sr0.4FeO3 (LSF) y LaNi0.6Fe0.4O3 (LNF) se utilizaron como soporte anódico, electrolito, barrera, cátodo y capa de contacto, respectivamente. Para la obtención de las celdas, los soportes anódicos se fabricaron mediante prensado uniaxial y las capas restantes se añadieron utilizando la técnica de aerografía, ensamblándolas mediante diferentes procesos de sinterización. Las celdas desarrolladas se han testeado electroquímicamente en un rango de temperaturas entre 750 y 865 °C. Además, se han llevado a cabo ensayos de degradación bajo corriente constante. Asimismo, para caracterizar la microestructura de las celdas, se ha utilizado un microscopio electrónico de barrido (SEM) equipado con un espectrómetro de rayos X por energía dispersiva (EDX).Los resultados obtenidos muestran que la incorporación de las capas catódicas y de contacto incrementan las densidades potencia y disminuyen las resistencias totales de las celdas respecto a la celda sin cátodo, especialmente al añadir la capa de contacto LNF. A pesar de la mejora obtenida, se han de realizar más ensayos a fin de optimizar el funcionamiento de los dispositivos SOFC en los ensayos de degradación.

The precise control of stem cell behavior, including differentiation, transdifferentiation, and reprogramming, is fundamental for safely and efficiently using human stem cells in regenerative medicine. Thanks to recent innovations and developments in the field of nanomedicine, as well as its integration with advanced molecular biology approaches, the possibility of engineering and restoring functions of complex tissues become reality. Multifunctional nanotechnological tools allow to finely control the release of growth factors, mRNA, and other molecules, to promote cell fate conversion, and to perform long-term tracking in vivo. Furthermore, stimulation approaches based on smart and biocompatible nanotransducers promise to remotely modulate the stem cell activity, paving the way for the actual exploitation of these technologies in the internal tissues of large-sized animals. In this review, the most innovative nanotechnology tools applied to stem cell-based regenerative medicine are presented, and their implications for future research and clinics are discussed.

Abstract The conservation of iron objects exposed to marine aerosol is threatened by the formation of akaganeite, a highly unstable Cl-bearing corrosion phase. As akaganeite formation is responsible of the exfoliation of the rust layer, chlorides trigger a cyclic alteration phenomenon that often ends with the total consumption of the iron core. To prevent this degradation process, movable iron elements (e.g. archaeometallurgical artefacts) are generally immersed in alkaline dechlorination baths. Aiming to transfer this successful method to the treatment of immovable iron objects, we propose the in-situ application of alkaline solutions through the use of highly absorbent wraps. As first step of this novel research line, the present work defines the best desalination solution to be used and optimizes its extraction yield. After literature review, a screening experimental design was performed to understand the single and synergic effects of common additives used for NaOH baths. Once the most effective variables were selected, an optimization design was carried out to determine the optimal conditions to be set during treatment. According to the experimental work here presented, the use of 0.7 M NaOH solutions applied at high temperatures (above 50 °C) is recommended. Indeed, these conditions enhance chloride extraction and iron leaching inhibition, while promoting corrosion stabilization.

Rivers are severely affected by human activities and many are simultaneously impacted by multiple stressors. Water diversion for hydropower generation affects ecosystem functioning of the bypassed reaches, which can alternate between periods with natural discharge and others with reduced flow that increase the surface of dry riverbeds. In parallel, urban pollution contributes a complex mixture of nutrients, organic matter, heavy metals, pesticides, and drugs, thus becoming an important stressor in rivers. However, there is little information on the interaction between both stressors on ecosystem functioning and, particularly, on organic matter processing, a key process linked to the input of energy to food webs. To assess the impact of water diversion and urban pollution on organic matter processing, we selected four rivers in a pollution gradient with a similar diversion scheme and compared reaches upstream and downstream from the diversion weirs. We measured leaf-litter decomposition and carbon dioxide (CO2) fluxes in both the wet channel and the dry riverbed. Water diversion and pollution in the wet channel did not affect CO2 fluxes but reduced microbial decomposition, whereas in the dry riverbed, their interaction reduced total and microbial decomposition and CO2 fluxes. Thus, both stressors affected organic matter processing stronger in dry riverbeds than in the wet channel. These results show that dry riverbeds must be taken into account to assess and manage the impacts of human activities on river ecosystems.

The habitat heterogeneity hypothesis states that increased habitat heterogeneity promotes species diversity through increased availability of ecological niches. We aimed at describing the local-scale (i.e. nest and adjacent substrate) effects of nests of the sea lamprey (Petromyzon marinus L.) as ecosystem engineer on macroinvertebrate assemblages. We hypothesized that increased streambed physical heterogeneity caused by sea lamprey spawning would modify invertebrate assemblages and specific biologic traits and promote reach-scale diversity. We sampled thirty lamprey nests of the Nive River, a river of the south western France with a length of 79.3 km and tributary of the Adour River, in three zones: the unmodified riverbed (upstream) and zones corresponding to the nest: the area excavated (pit) and the downstream accumulation of pebbles and cobbles (mound). The increased habitat heterogeneity created by lamprey was accompanied by biological heterogeneity with a reduced density of invertebrates (3777 ± 1332 individuals per m2 in upstream, 2649 ± 1386 individuals per m2 in pit and 3833 ± 1052 individuals per m2 in mound) and number of taxa (23.5 ± 3.9 taxa for upstream, 18.6 ± 3.9 taxa in pit and 21.2 ± 4.5 taxa for mound) in the pit compared to other zones. However the overall taxa diversity in nest increased with 82 ± 14 taxa compared to the 69 ± 8 taxa estimated in upstream zone. Diversity indices were consistent with the previous results indicating a loss of α diversity in pit but a higher β diversity between a pit and a mound than between two upstream zones, especially considering Morisita index accounting for taxa abundance. Trait analysis showed high functional diversity within zones with a reduced proportion of collectors, scrapers, shredders, litter/mud preference and small invertebrates in mound, while the proportion of “slabs, blocks, stones and pebbles” preference and largest invertebrates increased. Pit presented the opposite trend, while upstream had globally intermediate trait proportions. Our results highlight important effects on species and functional diversity due to habitat heterogeneity created by a nest-building species, what can ultimately influence food webs and nutrient processes in river ecosystems.

Gd flake samples were prepared by conventional ball milling technique starting from rapidly quenched Gd ribbons and followed by vacuum annealing in different conditions. Heat treatments were conducted in a vacuum at selected temperatures up to 600 K. The structural features, magnetic and magnetocaloric properties were comparatively analyzed. The change in magnetic entropy was calculated using an experimental set of magnetic isotherms measured in a wide range of temperatures. The variations in the refrigeration capacity and the exponent of the magnetic entropy change in the external magnetic field were carefully calculated and analyzed.

FeNi films of different thickness and FeNi/(Fe, Co)/FeNi trilayers were prepared by magnetron sputtering deposition onto glass substrates. The permalloy films had a columnar microstructure. The detailed analysis of the magnetic properties based on the magnetic and magneto-optical measurements showed that at thicknesses exceeding a certain critical thickness, hysteresis loops acquire a specific shape and the coercive force of the films increase sharply. The possibility of the estimation of the perpendicular magnetic anisotropy constant using the Murayama equation for the thickness dependence of saturation field was demonstrated. The results of studies of the structural and magnetic properties of FeNi films laminated by Fe and Co spacers with different thickness are presented.

Resumen: En este trabajo se propone el empleo de la técnica de electro-hilado para la síntesis de fibras cerámicas que puedan ser empleadas como constituyentes de electrodos de pilas de combustible de óxido sólido. Concretamente se ha demostrado el aumento en la capacidad de producción de fibras cerámicas (en un orden de magnitud) gracias a la sustitución de un inyector simple por uno múltiple (provisto de 10 agujas). Además, los diámetros, longitudes, tamaños de cristal y área superficial de las fibras obtenidas indican que estas podrían ser empleadas para fabricar electrodos con una microestructura altamente porosa, fácilmente infiltrable y donde se maximice la región donde tiene lugar la reacción de reducción de oxígeno y el transporte de gases y cargas. Abstract: In this work, we propose the use of electro-spinning technique for the synthesis of ceramic fibers that can be used as SOFC's electrodes. In particular, the increase of ceramic fibers production capacity (up to one order of magnitude) has been demonstrated through the replacement of a single injector by a multiple injector (equipped with 10 needles). Moreover, the diameters, lengths, glass sizes and surface area of the obtained fibers indicate that these fibers could be used to manufacture highly porous electrodes that can be easily infiltrated, having micro-structure where the oxygen reduction reaction region takes place is maximized and also the gases and charges transportations properties are improved. Palabras clave: Pilas de combustible de óxido sólido, Electro-hilado, Nanofibras, Inyector múltiple, Keywords: Solid oxide fuel cells, Electrospinning, Nanofibers, Multi-injector

The first fluorination of the cuspidine-related phases of Ln4(Al2O7□)O2 (where Ln = Sm, Eu, Gd) is reported. A low-temperature reaction with poly(vinylidene difluoride) lead to the fluorine being substituted in place of oxygen and inserted into the vacant position between the dialuminate groups. X-ray photoelectron spectroscopy shows the presence of the F 1s photoelectron together with an increase in Al 2p and rare-earth 4d binding energies supporting F incorporation. Energy-dispersive X-ray spectroscopy analyses are consistent with the formula Ln4(Al2O6F2)O2, confirming that substitution of one oxygen by two fluoride atoms has been achieved. Rietveld refinements show an expansion in the cell upon fluorination and confirm that the incorporation of fluoride in the Ln4(Al2O7□)O2 structure results in changes in Al coordination from four to five. Thus, the isolated tetrahedral dialuminate Al2O7 groups are converted to chains of distorted square-based pyramids. These structural results are also discussed based on Raman spectra.

The development of magnetoactive microsystems for targeted drug delivery, magnetic biodetection, and replacement therapy is an important task of present day biomedical research. In this work, we experimentally studied the mechanical force acting in cylindrical ferrogel samples due to the application of a non-uniform magnetic field. A commercial microsystem is not available for this type of experimental study. Therefore, the original experimental setup for measuring the mechanical force on ferrogel in a non-uniform magnetic field was designed, calibrated, and tested. An external magnetic field was provided by an electromagnet. The maximum intensity at the surface of the electromagnet was 39.8 kA/m and it linearly decreased within 10 mm distance from the magnet. The Ferrogel samples were based on a double networking polymeric structure which included a chemical network of polyacrylamide and a physical network of natural polysaccharide guar. Magnetite particles, 0.25 micron in diameter, were embedded in the hydrogel structure, up to 24% by weight. The forces of attraction between an electromagnet and cylindrical ferrogel samples, 9 mm in height and 13 mm in diameter, increased with field intensity and the concentration of magnetic particles, and varied within 0.1–30 mN. The model provided a fair evaluation of the mechanical forces that emerged in ferrogel samples placed in a non-uniform magnetic field and proved to be useful for predicting the deformation of ferrogels in practical bioengineering applications.

Discharge reduction, as caused by water diversion for hydropower, and fine sediments deposition, are prevalent stressors that may affect multiple ecosystem functions in streams. Periphytic biofilms play a key role in stream ecosystem functioning and are potentially affected by these stressors and their interaction. We experimentally assessed the interactive effects of discharge and fine sediments on biofilm metabolism in artificial indoor channels using a factorial split-plot design with two explanatory variables: water discharge (20, 39, 62, 141 and 174 cm3 s-1) and fine sediments (no sediment or 1100 mg L-1 of sediments). We incubated artificial tiles for 25 days in an unpolluted stream to allow biofilm colonization, and then placed them into the indoor channels for acclimation for 18 days. Subsequently, we manipulated water discharge and fine sediments and, after 17 days, we measured biofilm chlorophyll-a concentration and metabolism. Water velocity (range, 0.5 to 3.0 cm s-1) and sediment deposition (range, 6.1 to 16.6 mg cm-2) increased with discharge, the latter showing that the effect of increased inputs prevailed over sloughing. In the no-sediment treatments, discharge did not affect biofilm metabolism, but reduced chlorophyll-a. Sediments, probably as a consequence of nutrients released, promoted metabolism of biofilm and chlorophyll-a, which became independent of water discharge. Our results indicate that pulses of fine sediments can promote biofilm algal biomass and metabolism, but show interactive effects with discharge. Although discharge reduction can affect the abundance of basal resources for food webs, its complex interactions with fine sediments make it difficult to forecast the extent and direction of the changes.

Las plantaciones de eucalipto (género Eucalyptus) tienen una amplia distribución a escala global y causan preocupación por los efectos que pueden ocasionar sobre el medio ambiente. En este trabajo revisamos la evolución de la superficie cubierta por los eucaliptos en Euskadi y evaluamos sus efectos ambientales a partir de la bibliografía científica existente sobre esta región y sobre la península ibérica. Entre 1986 y 2019, la superficie de plantaciones de eucaliptos se ha cuadruplicado, pasando de 4.866 a 19.643 ha, proceso este que está acelerándose a causa de la plaga de la banda marrón del pino. Los estudios publicados muestran de manera sistemática que las plantaciones de eucaliptos en Euskadi y el resto de la Península tienen un efecto medioambiental negativo si se compara con las plantaciones de pino y, especialmente, con los bosques nativos. Las plantaciones de eucalipto modifican las características del suelo y disminuyen la biodiversidad. Entre los organismos más afectados se encuentran los hongos, líquenes, plantas herbáceas, anfibios, aves e invertebrados acuáticos. También se detectan alteraciones en el funcionamiento del ecosistema, en procesos como la descomposición de hojarasca. Aunque algunas afecciones parecen ser consecuencia de la intensidad con la que se explotan estas plantaciones y podrían reducirse mediante medidas correctoras, otros efectos parecen guardar relación con las características intrínsecas del eucalipto que, en consecuencia, no pueden modificarse. Es previsible que la magnitud de los impactos se agrave conforme se incremente la superficie cubierta por eucaliptales así como el número de rotaciones en sus explotaciones. ___________________________________________ Abstract Eucalyptus plantations are widely distributed throughout the world, thus creating concern due to their potential environmental effects. In this work we analyse the evolution of the coverage of eucalypts in the Basque Country and assess their environmental effects based on the scientific literature from this region and from the Iberian Peninsula. From 1986 to 2019 the area covered by eucalypt plantations increased fourfold, from 4,866 to 19,643 ha, a process that is accelerating as a consequence of the pine needle blight. The research so far published shows systematically that eucalypt plantations in the Basque Country and in the rest of the peninsula have detrimental environmental effects, compared to pine plantations and, especially, to native forests. Eucalypt plantations alter soil characteristics and reduce biodiversity. Fungi, lichens, herbaceous plants, amphibians, birds and aquatic invertebrates are among the most seriously affected groups of organisms. Ecosystem processes, such as leaf-litter breakdown, are also affected. Some of these effects seem to be a consequence of the intensity of exploitation in these plantations and, thus, could be reduced by means of improved management; other effects seem to relate to the intrinsic characteristics of the eucalypts, which cannot be modified. The magnitude of the impacts will likely increase with the area covered by eucalypt plantations, as well as with the number of crop rotations.

La cristalografía de rayos X resulta una técnica analítica fundamental para el estudio exhaustivo de la estructura cristalina de los materiales. A pesar de su enorme relevancia tanto a nivel científico como industrial, su cobertura respecto a análisis avanzados ha sido insuficiente hasta ahora. Por lo tanto, en este trabajo mostramos diferentes posibilidades de la difracción de rayos X, muy útil para obtener en algunos casos información crítica de nuestros materiales.

Glioblastoma multiforme (GBM) is one of the most aggressive types of brain cancer, characterized by rapid progression, resistance to treatments, and low survival rates; the development of a targeted treatment for this disease is still today an unattained objective. Among the different strategies developed in the latest few years for the targeted delivery of nanotherapeutics, homotypic membrane-membrane recognition is one of the most promising and efficient. In this work, we present an innovative drug-loaded nanocarrier with improved targeting properties based on the homotypic recognition of GBM cells. The developed nanoplatform consists of boron nitride nanotubes (BNNTs) loaded with doxorubicin (Dox) and coated with cell membranes (CM) extracted from GBM cells (Dox-CM-BNNTs). We demonstrated as Dox-CM-BNNTs are able to specifically target and kill GBM cells in vitro, leaving unaffected healthy brain cells, upon successful crossing an in vitro blood-brain barrier model. The excellent targeting performances of the nanoplatform can be ascribed to the protein component of the membrane coating, and proteomic analysis of differently expressed membrane proteins present on the CM of GBM cells and of healthy astrocytes allowed the identification of potential candidates involved in the process of homotypic cancer cell recognition.

This study addresses the development of gel-based magnetic material in the purposes of biomedical applications in the fields of tissue engineering, regenerative medicine, drugs delivery and magnetic biosensing. Ferrogels were synthesized by radical polymerization of acrylamide in a stable aqueous suspension of γ-Fe2.04O2.96 nanoparticles (NPs) fabricated by the laser target evaporation technique. Gel network density was set to 1:100, the concentrations of imbedded NPs (average mean diameter of about 11 nm) were fixed at 0.00, 0.25 or 0.75% by weight. Saturation magnetization of the gels showed a linear dependence on concentration of NPs. The main task of proposed investigation was to determine the contribution of the presence of NPs to the change of the physical properties of gels and their biocompatibility. We found that the gradual increase of NPs concentration in the gel network resulted in the significant increase of the gel’s Young modulus, effective viscosity, negative value of electrical potential and adhesion index for both the human dermal fibroblasts and the human peripheral blood leucocytes. We concluded that from viewpoint of biomedical applications, the inclusion of small amount of NPs into the polymer network significantly enhances the mechanical and electrical properties of ferrogels, and improves biocompatibility of these systems. Keywords: Hydrogel, Magnetic nanoparticles, Viscoelasticity, Electrical potential, Cells adhesion, Biomedical engineering

Habitat complexity can influence predation rates (e.g. by providing refuge) but other ecosystem processes and species interactions might also be modulated by the properties of habitat structure. Here, we focussed on how complexity of artificial habitat (plastic plants), in microcosms, influenced short-term processes driven by three aquatic detritivores. The effects of habitat complexity on leaf decomposition, production of fine organic matter and pH levels were explored by measuring complexity in three ways: 1. as the presence vs. absence of habitat structure; 2. as the amount of structure (3 or 4.5 g of plastic plants); and 3. as the spatial configuration of structures (measured as fractal dimension). The experiment also addressed potential interactions among the consumers by running all possible species combinations. In the experimental microcosms, habitat complexity influenced how species performed, especially when comparing structure present vs. structure absent. Treatments with structure showed higher fine particulate matter production and lower pH compared to treatments without structures and this was probably due to higher digestion and respiration when structures were present. When we explored the effects of the different complexity levels, we found that the amount of structure added explained more than the fractal dimension of the structures. We give a detailed overview of the experimental design, statistical models and R codes, because our statistical analysis can be applied to other study systems (and disciplines such as restoration ecology). We further make suggestions of how to optimise statistical power when artificially assembling, and analysing, 'habitat complexity' by not confounding complexity with the amount of structure added. In summary, this study highlights the importance of habitat complexity for energy flow and the maintenance of ecosystem processes in aquatic ecosystems.

Magnetic biosensors are an important part of biomedical applications of magnetic materials. As the living tissue is basically a “soft matter.” this study addresses the development of ferrogels (FG) with micron sized magnetic particles of magnetite and strontium hexaferrite mimicking the living tissue. The basic composition of the FG comprised the polymeric network of polyacrylamide, synthesized by free radical polymerization of monomeric acrylamide (AAm) in water solution at three levels of concentration (1.1 M, 0.85 M and 0.58 M) to provide the FG with varying elasticity. To improve FG biocompatibility and to prevent the precipitation of the particles, polysaccharide thickeners—guar gum or xanthan gum were used. The content of magnetic particles in FG varied up to 5.2 wt % depending on the FG composition. The mechanical properties of FG and their deformation in a uniform magnetic field were comparatively analyzed. FG filled with strontium hexaferrite particles have larger Young’s modulus value than FG filled with magnetite particles, most likely due to the specific features of the adhesion of the network’s polymeric subchains on the surface of the particles. FG networks with xanthan are stronger and have higher modulus than the FG with guar. FG based on magnetite, contract in a magnetic field 0.42 T, whereas some FG based on strontium hexaferrite swell. Weak FG with the lowest concentration of AAm shows a much stronger response to a field, as the concentration of AAm governs the Young’s modulus of ferrogel. A small magnetic field magnetoimpedance sensor prototype with Co68.6Fe3.9Mo3.0Si12.0B12.5 rapidly quenched amorphous ribbon based element was designed aiming to develop a sensor working with a disposable stripe sensitive element. The proposed protocol allowed measurements of the concentration dependence of magnetic particles in gels using magnetoimpedance responses in the presence of magnetite and strontium hexaferrite ferrogels with xanthan. We have discussed the importance of magnetic history for the detection process and demonstrated the importance of remnant magnetization in the case of the gels with large magnetic particles.

Biodegradable poly(α-hydroxyacids) have gained increasing interest in the biomedical field for their use as cell microcarriers thanks to their biodegradability, biocompatibility, tunable mechanical properties/degradation rates and processability. The synthesis of these poly(α-hydroxyacids) can be finely controlled to yield (co)polymers of desired mechanical properties and degradation rates. On the other hand, by simple emulsion-solvent evaporation techniques, microspheres of controlled size and size distribution can be fabricated. The resulting microspheres can be further surface-modified to enhance cell adhesion and proliferation. As a result of this process, biodegradable microcarriers with advanced functionalities and surface properties that can be directly employed as injectable cell microcarriers are obtained.