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Porous tantalum has been extensively used in orthopaedic surgery, including uncemented total knee arthroplasty (TKA). Favourable results were reported with earlier monobloc tibial components and the design evolved to modular implants. We aimed to analyse possible causes for extensive medial tibia bone loss, resulting in modular porous tantalum tibia baseplate fracture after primary TKA. Retrieved tissue samples were scanned with 3 MeV focused proton beam for Proton-Induced X-ray Emission (micro-PIXE) elemental analysis. Fractographic and microstructural analysis were performed by stereomicroscopy. A full 3D finite-element model was made for numerical analysis of stress–strain conditions of the tibial baseplate. Histological examination of tissue underneath the broken part of the tibial baseplate revealed dark-stained metal debris, which was confirmed by micro-PIXE to consist of tantalum and titanium. Fractographic analysis and tensile testing showed that the failure of the tibial baseplate fulfilled the criteria of a typical fatigue fracture. Microstructural analysis of the contact surface revealed signs of bone ingrowth in 22.5% of the surface only and was even less pronounced in the medial half of the tibial baseplate. Further studies are needed to confirm the responsibility of metal debris for an increased bone absorption leading to catastrophic tibial tray failure.

Breeding and engineering of biofortified crops will benefit from a better understanding of bottlenecks controlling micronutrient loading within the seeds. However, few studies have addressed the changes in micronutrient concentrations, localization, and speciation occurring over time. Therefore, we studied spatial patterns of zinc and iron accumulation during grain development in two barley lines with contrasting grain zinc concentrations. Microparticle-induced-X-ray emission and laser ablation-inductively coupled plasma mass spectrometry were used to determine tissue-specific accumulation of zinc, iron, phosphorus, and sulfur. Differences in zinc accumulation between the lines were most evident in the endosperm and aleurone. A gradual decrease in zinc concentrations from the aleurone to the underlying endosperm was observed, while iron and phosphorus concentrations decreased sharply. Iron co-localized with phosphorus in the aleurone, whereas zinc co-localized with sulfur in the sub-aleurone. We hypothesize that differences in grain zinc are largely explained by the endosperm storage capacity. Engineering attempts should be targeted accordingly.

Tartary buckwheat (Fagopyrum tataricum Gaertn.) is a gluten-free pseudo-cereal crop with a grain nutrient profile that makes it an excellent alternative foodstuff. The distribution of calcium (Ca), magnesium (Mg), phosphorus (P) and sulphur (S) was investigated by micro-PIXE (particle induced X-ray emission) to resolve allocation and concentration of the elements in nine distinct grain tissues. Magnesium, P and S were preferentially allocated to the cotyledons and the embryonic axis (both inner and outer tissues), and Ca was predominant in the pericarp where two Ca-rich layers were observed. Allocation of P and S to aleurone suggests that this layer of cells, although not as prominent as in cereal grain, is rich in phytate and proteins. Quantitative information on spatial distribution of mineral elements in the edible grain may be useful in the technological processing of the grain and particularly in reducing the amount of mineral-element loss during milling.

The olive (Olea europaea L.) leaves, as central part of the olive tree metabolism, has important role in determination of olive nutrient status and fertilizers requirements. Thus, the aim of our study was to define differences in leaf phosphorous (P), potassium (K), calcium (Ca) and magnesium (Mg) concentrations between Leccino and Istarska bjelica cultivars. The field experiment included total of 18 olive trees per cultivar, equally distributed in six locations all along Croatian Adriatic coast. Sampling for leaf bulk analysis was conducted during harvest, winter and pruning period (2017/2018) (n=54). In the greenhouse experiment, with 150 one-year old olive seedlings per cultivar, leaves were sampled for bulk and micro-PIXE analysis in November 2019 (n=3). Field experiment results shown that Leccino cv. leaves has higher bulk P, Ca and Mg concentrations when compared to Istarska bjelica cv.. In greenhouse experiment total Ca and Mg leaf concentrations were higher in Leccino cv. with elevated K concentration in Istarska bjelica cv.. Micro-PIXE analysis revealed that larger Ca and Mg bulk concentrations in Leccino cv. leaves can be linked to higher Ca concentration in epidermis and in leaf blade tissues as well as with higher Mg concentration in mostly all leaf tissues, with exception the bundle sheath cells and the main vascular bundle. While P concentration was higher in epidermis and spongy mesophyll of Leccino cv. leaves, K concentration didn’t differ between selected cultivars in any of the leaf tissues examined.

In the EU Drinking Water Directive (EU DWD) 2020/2184, the approach of “water safety plan” as suggested by the WHO, has been individuated as the correct tool for water utilities to ensure safe drinkable water. The ADRION Interreg project MUHA moved from the necessity to effectively link different aspects of the water related risks management in an improved response system, integrating functions of analysis, forecasting and incident command systems. This paper aims at describing the rationale of the MUHA project and presenting some of the main outcomes.

Human hair absorbs numerous biomolecules from the body during its growth. This can act as a fingerprint to determine substance intake of an individual, which can be useful in forensic studies. The cocaine concentration profile along the growth axis of hair indicates the time evolution of the metabolic incorporation of cocaine usage. It could be either assessed by chemical extraction and further analysis of hair bundels, or by direct single hair fibre analysis with mass spectroscopy imaging (MSI). Within this work, we analyzed the cocaine distribution in individual hair samples using MeV-SIMS. Unlike conventional surface analysis methods, we demonstrate high yields of nonfragmented molecular ions from the surface of biological materials, resulting in high chemical sensitivity and non-destructive characterisation. Hair samples were prepared by longitudinally cutting along the axis of growth, leaving half-cylindrical shape to access the interior structure of the hair by the probing ion beam, and attached to the silicon wafer. A focused 5.8 MeV 35Cl6+ beam was scanned across the intact, chemically pristine hair structure. A non-fragmented protonated [M+ H]+ cocaine molecular peak at m/z = 304 was detected and localized along the cross-section of the hair. Its intensity exhibits strong fluctuations along the direction of the hair’s growth, with pronounced peaks as narrow as 50 micrometres, corresponding to a metabolic incorporation time of approx. three hours.

International audience; Secondary ion mass spectrometry (SIMS), based on primary ions within the MeV energy domain, also known as MeV-SIMS, is a subject of increasing scientific interest. The main drive for the interest in the development of MeV-SIMS is the ability to desorb high yields of large non-fragmented organic molecular ions from the sample surface. This makes MeV-SIMS particulary useful in imaging of biological tissues.Imaging methods based on scanning a focused primary ion beam are associated with demanding focusing of the heavy energetic ions. As an alternative, stigmatic imaging mode has been studied here, applying point-to-point imaging characteristics of secondary ions in the linear Time-Of-Flight mass spectrometer. In stigmatic imaging approaches, spatial resolution is independent of the focussed spot size of the ionising primary ion beam, but instead dependant on the ability of the ion optics to project an image of the ion distributions removed from the surface onto a position sensitive ion detector.

Halophytes are able to tolerate relatively high concentrations of hazardous metals in a growing substrate, what makes them suitable candidates for phytoremediation of metal-contaminated soils. In this work, we aimed to study the physiological responses of the halophyte Sesuvium portulacastrum L. to Ni, with main focus on Ni localization, compartmentation and ligand environment, to decipher Ni tolerance and toxicity mechanisms. Seedlings were grown in hydroponic nutrient solution containing 0, 25, 50 and 100 μM Ni as NiCl2 for 3 weeks. Ni localization in leaves was assessed by micro-proton-induced X-ray emission (micro-PIXE). Ni ligand environment was studied by Ni K-edge X-ray absorption near edge structure (XANES). In addition, Ni-soluble, weakly bound/exchangeable and insoluble leaf tissue fractions were determined by sequential extraction. Results show that S. portulacastrum is able to tolerate up to ~ 500 μg g−1 dry weight (DW) of Ni in the shoots without significant growth reduction. At higher Ni concentrations (> 50 μM Ni in nutrient solution), chloroses were observed due to the accumulation of Ni in photosynthetically active chlorenchyma as revealed by micro-PIXE. Water storage tissue represented the main pool for Ni storage. Incorporation of Ni into Ca-oxalate crystals was also observed in some specimens, conferring tolerance to high leaf Ni concentrations. The majority of Ni (> 70%) was found in soluble tissue fraction. Ni K XANES revealed Ni bound mainly to O- (55%) and N-ligands (45%). Ni toxicity at higher Ni levels was associated with Ni binding to amino groups of proteins in cytosol of chlorenchyma and increased level of lipid peroxidation. Proline levels also increased at high Ni exposures and were associated with Ni-induced oxidative stress and alteration of water regime.

We study the Lie ring niln of all strictly upper-triangular n​×​n matrices with entries in Z. Its complete homology for n​≤​8 is computed. We prove that every pm-torsion appears in H∗(niln;Z) for p...

Breeding and engineering of biofortified crops will benefit from a better understanding of bottlenecks controlling micronutrient loading within the seeds. However, few studies have addressed the changes in micronutrient concentrations, localization, and speciation occurring over time. Therefore, we studied spatial patterns of zinc and iron accumulation during grain development in two barley lines with contrasting grain zinc concentrations. Microparticle-induced-X-ray emission and laser ablation-inductively coupled plasma mass spectrometry were used to determine tissue-specific accumulation of zinc, iron, phosphorus, and sulfur. Differences in zinc accumulation between the lines were most evident in the endosperm and aleurone. A gradual decrease in zinc concentrations from the aleurone to the underlying endosperm was observed, while iron and phosphorus concentrations decreased sharply. Iron co-localized with phosphorus in the aleurone, whereas zinc co-localized with sulfur in the sub-aleurone. We hypothesize that differences in grain zinc are largely explained by the endosperm storage capacity. Engineering attempts should be targeted accordingly.

MeV-SIMS is an emerging mass spectrometry imaging method that employs fast, heavy ions to desorb secondary molecules from the analyzed sample. High yields and low fragmentation rates of large molecules, associated with the dominating electronic sputtering process, make it particularly useful in biomedical research, where insight into the distribution of organic molecules is vital. Both yield and fragmentation of desorbed molecules in MeV-SIMS rely on characteristics of the primary ion but may also be impaired by poor instrumental settings. After utilizing secondary ion optics in the linear mass spectrometer at the micro-analytical center of the Jožef Stefan Institute, we demonstrate very efficient detection of secondary ions. As a result, the secondary ion yield, using such settings, solely depends on the species and the characteristics of the primary ion. In order to analyze the yield dependence on the primary ion energy, and the corresponding stopping power within the electronic excitation regime, we used a continuous electron multiplier detector to measure the primary ion current during each measurement of the mass spectra. Secondary ion yield as a function of the primary ion energy and charge is presented as well as fragmentation rates of organic molecules arginine and leu-enkephalin. Other influential instrumental drawbacks are also studied, and their effect on the results is discussed.

In Parkinson’s disease, the depletion of iron-rich dopaminergic neurons in nigrosome 1 of the substantia nigra precedes motor symptoms by two decades. Monitoring this neuronal depletion, at an early disease stage, is needed for early diagnosis. Magnetic resonance imaging (MRI) is particularly suitable for this task due to its sensitivity to iron. However, the exact mechanisms of MRI contrast in nigrosome 1 are not well understood, hindering the development of powerful biomarkers. We demonstrate that the dominant contribution to the effective transverse MRI relaxation rate in nigrosome 1 originates from iron accumulated in dopaminergic neurons. We link quantitatively to the product of cell density and local iron concentration in dopaminergic neurons, combining quantitative 3D iron histology, biophysical modeling, and quantitative MRI on post mortem brain tissue. It is now theoretically possible to monitor dopaminergic neuron depletion, in vivo, as an early diagnostic tool for Parkinson’s disease.

Additional file 1 Fig. S1. Growth of Brassica oleracea accessions (C6 and F103) cultivated hydroponically for 2 weeks in solutions containing 0.025 mM P (Low P) and 0.25 mM P (High P). Fig. S2. Root (a), shoot (b) and plant (c) phosphorus (P) content of two Brassica oleracea accessions (C6 and F103) grown hydroponically for 2 weeks in solutions containing 0.025 mM P (Low P; LP) and 0.25 mM P (High P; HP). Data are means (n = 5–6) and standard errors. Asterisks indicate statistically significant differences (two-way analysis of variance followed by Holm-Sidak post hoc test at P

Biljkama su potrebni različiti makro- i mikroelementi za normalan rast i razvoj. Navedeni elementi imaju različite uloge u biljnoj stanici, poput tvorbe strukturalnih komponenata u makromolekulama, kofaktori su enzimatskih reakcija ili sudjeluju u osmoregulacijskim procesima biljke. Mineralni sastav lista prvenstveno je povezan s brojnim fundamentalnim procesima kao i sekundarnim metabolizmom biljaka. Maslina (Olea europaea L.) je jedna od najznačajnijih kultura, posebice u skupini voćnih vrsta, uzgajanih na području Mediterana. Cilj ovog rada bio je utvrditi distribuciju makro i mikroelemenata u poprečnom prerezu listova sorte ‘Istarska bjelica’ primjenom protonima inducirane emisije rendgenskoga zračenja (mikro-PIXE), multi-elementne i potpuno kvantitativne tehnike čija je rezolucija < 1 μm. U preliminarnim istraživanjima poprečnog prereza listova masline primjenom mikro-PIXE utvrđen je različit sadržaj kalija (K), fosfora (P), kalcija (Ca), magnezija (Mg), sumpora(S), klora (Cl), mangana (Mn), željeza (Fe) i cinka (Zn). Koncentracije K dostigle su 30.00 g/kg suhe tvari (ST) i velikim su djelom bile raspodijeljene u asimilacijskom parenhimu. Najveće koncentracije P utvrđene su u/oko vaskularnog tkiva te asimilacijskog parenhima. Prosječna koncentracija P u cijelom poprečnom prerezu lista iznosila je 2.10 g/kg ST. Kalcij je prevladavao u epidermalnom tkivu, dok je prosječna koncentracija Ca iznosila 5.50 g/kg ST. Magnezij je bio ravnomjerno raspoređen u listu s prosječnom vrijednosti od 1.78g/kg ST. Distribucija S bila je vrlo slična onoj P, osim u blizini provodnog staničja. Prosječna koncentracija S u cijelom poprečnom presjeku lista iznosila je 0.93 g/kg ST. Nakupljanje Cl u većim količinama zabilježeno je u žilnim ovojnicama ; prosječna koncentracija u poprečnom prerezu lista iznosila je 1.70 g/kg ST. Mangan, Fe i Zn bili su podjednako raspoređeni s prosječnim koncentracijama 25, 62 i 17 mg/kg ST.

The problem of the optimal approximation of circular arcs by parametric polynomial curves is considered. The optimality relates to the Hausdorff distance and has not been studied yet in the literature. Parametric polynomial curves of low degree are used and a geometric continuity is prescribed at the boundary points of the circular arc. A general theory about the existence and the uniqueness of the optimal approximant is presented and a rigorous analysis is done for some special cases for which the degree of the polynomial curve and the order of the geometric smoothness differ by two. This includes practically interesting cases of parabolic G 0 , cubic G 1 , quartic G 2 and quintic G 3 interpolation. Several numerical examples are presented which confirm theoretical results.

In accordance to their roles in plants, mineral elements are differentially distributed between different cell types and leaf tissues. They provide structure to membranes, act as enzymatic co-factors and constitute important macromolecules. Adequate conveyance and allocation of elements throughout the leaf ensures continuation of fundamental metabolic processes. Olive (Olea europaea L.) is one of the most important fruit crops in the Mediterranean area, exhibiting high varietal diversity throughout the basin. The main objective of this trial was to determine the distribution of macro- and microelements (potassium (K), phosphorus (P), calcium (Ca), magnesium (Mg), sulphur (S), chlorine (Cl), iron (Fe), zinc (Zn), and manganese (Mn)) in leaf cross-sections of Istarska bjelica and Leccino olive varieties, using multi-elemental, micro-particle induced X-ray emission (micro- PIXE) technique. With an exception of Ca, concentrations of leaf K, P, Mg, S and Cl did not differ significantly between the two varieties, amounting to 24.51, 1.54, 1.37, 0.88, 1.29 g kg-1 dry weight (DW) for Istarska bjelica and 22.93, 1.37, 1.75, 0.95, 1.15 g kg- 1 DW for Leccino respectively. Potassium was largely allocated at the palisade mesophyll of both varieties, however high K concentrations were also determined at the spongy mesophyll, beneath the main vasculature. Phosphorus ions mainly surrounded vascular tissues and to a lesser degree accumulated in the palisade mesophyll of both varieties. Highest Ca concentrations were detected in epidermis, followed by a high allocation around vascular tissues of both varieties. Leaf Ca concentration was significantly higher in Leccino (8.07 g kg-1 DW) than in Istarska bjelica (5.55 g kg-1 DW). Magnesium was evenly dispersed in leaves of both varieties, whereas S predominated in the palisade mesophyll and Cl accumulated mainly around the bundle sheath cells. Microelements were evenly distributed throughout the leaf cross-sections of both varieties, recording no significant differences in their leaf concentrations.

In this paper we consider the relationship between order and topology in the vector lattice $C_b(X)$ of all bounded continuous functions on a Hausdorff space $X$. We prove that the restriction of $f\in C_b(X)$ to a closed set $A$ induces an order continuous operator iff $A=\overline{\mathrm{Int} A}.$ This result enables us to easily characterize bands and projection bands in $C_0(X)$ and $C_b(X)$ through the one-point compactification and the Stone-\v{C}ech compactification of $X$, respectively. With these characterizations we describe order complete $C_0(X)$ and $C_b(X)$-spaces in terms of extremally disconnected spaces. Our results serve us to solve an open question on lifting un-convergence in the case of $C_0(X)$ and $C_b(X)$.

Element profile signatures of needle tissues differentiated four tissues: epidermis (main contributor: calcium), endodermis (main contributors: magnesium, sulphur and manganese), mesophyll (main contributor: potassium), and transfusion parenchyma (main contributor: zinc). Distribution of elements in cross-sections of Scots pine (Pinus sylvestris L.) needles was investigated using micro-proton-induced X-ray emission. Tissue-specific distributions of magnesium (Mg), sulphur (S), calcium (Ca), phosphorus (P), potassium (K), chlorine (Cl), manganese (Mn), iron (Fe), zinc (Zn), aluminium (Al) and silicon (Si) were resolved in a quantitative manner. Distribution maps and tissue-specific concentrations revealed the largest concentration of Ca in epidermis, of Mg, S and Mn in endodermis, of K in mesophyll and phloem and of Zn in transfusion parenchyma. Phosphorus, Cl, Fe, Al and Si did not exhibit apparent tissue-specific distribution. Inverse allocation of P and Ca was observed, a likely mechanism to prevent their precipitation. Taking the area of tissues into account, relative element distribution calculations indicated that mesophyll contained the majority of the elements studied, except Ca, which predominated in the epidermis (79% of total Ca concentration) and Mn, which predominated in the endodermis (40% of total Mn concentration). When considering a complete element profile of a particular tissue, four clusters were differentiated, which generally supported single-element observations. The first cluster differentiated mesophyll, xylem, phloem, transfusion tracheids and Strasburger cells with predominance of K, the second cluster differentiated epidermis on the basis of Ca, the third cluster differentiated endodermis with contributions from Mg, S and Mn, and the fourth cluster differentiated transfusion parenchyma with contribution from Zn. Information on tissue-specific-element allocations will complement structural and functional knowledge of needle tissues and advance our understanding of element/nutrient transfers in Scots pine.