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Looking at Harnack inequlity in Harmonic Spaces we complete the well known Tchebyshev inequality for positive integrable function with an oposite one. 2020 MSC: Primary: 42A10, 41A65 Secondary: 54D30, 54D40, 60135

We study a shape optimization problem involving a solid $$K\subset {\mathbb {R}}^n$$ K ⊂ R n that is maintained at constant temperature and is enveloped by a layer of insulating material $$\Omega $$ Ω which obeys a generalized boundary heat transfer law. We minimize the energy of such configurations among all $$(K,\Omega )$$ ( K , Ω ) with prescribed measure for K and $$\Omega $$ Ω , and no topological or geometrical constraints. In the convection case (corresponding to Robin boundary conditions on $$\partial \Omega $$ ∂ Ω ) we obtain a full description of minimizers, while for general heat transfer conditions, we prove the existence and regularity of solutions and give a partial description of minimizers.

The aim of this study was to identify by classification and regression tree (CART) analysis groups of patients with different survival patterns in a population of patients with heart failure and reduced left ventricular ejection fraction (HFrEF) by using standard methods of heart function assessment, as well as well as utilizing non-traditional approaches for determining hydration and nutritional status in HF patients—lung ultrasonography (LUS) and bioimpedance spectroscopy (BIS) analysis. Eligible patients with a left ventricular ejection fraction (LVEF) below 45% were identified via the daily echocardiography assessments. LUS was performed with patients in the supine position, for a total of 28 sites per complete examination. The hydration state and the body composition were assessed using a portable whole-body BIS device. Our study included 151 patients (69.2% males) with a mean age of 67.1 years. During the follow-up 53 (35.1%) patients died. Using the CART algorithm, we identified five groups based on serum sodium, the severity of NYHA class, serum urea and systolic blood pressure. When comparing the two models, the model derived from the CART analysis showed better predictive power than the conventional Cox model (c-index 0.790, 95% CI 0.723–0.857 vs. 0.736, 95%CI 0.664–0.807, p

The Anisian depositional history in the Western Tethys realm provides the possibility to study the stepwise opening of the Neo-Tethys, and is well preserved in the sedimentary record of the Northern Calcareous Alps. Whereas the depositional characteristic in the Early (to early Middle) Anisian is characterized by shallow-water carbonates, formed in a semi-restricted environment, the situation changed in the Middle Anisian. A rapid increase of subsidence resulted in an abrupt deepening event with deposition of deeper-water limestones, in some cases even with chert nodules, sometimes with resedimented shallow-water debris intercalated in radiolaria-filament wackestones, or with clayey or marly intercalations. This abrupt deepening, termed the Annaberg Event, is followed by a shallow-water carbonate evolution. The deeper-water limestones can be dated by conodonts and shallow-water organisms like calcareous algae or foraminifera from the resedimented intercalations as Late Bithynian to Early Pelsonian. In contrast to the Early Anisian microbial carbonates, formed under semi-restricted conditions, the Middle Anisian (Pelsonian) shallow-water carbonates were formed under fully marine influence and a diverse fauna and flora was, therefore, able to counterbalance the rapid subsidence by increasing carbonate production. During Middle Anisian times, the newly tectonically created accommodation space became rapidly filled by shallow-water carbonates. At the end of the Middle Anisian (Late Pelsonian), the final break-up of the Neo-Tethys led to a rapid decrease of carbonate production and widespread deposition of deep-marine and condensed limestones. This drowning event (Reifling Event) was accompanied by the formation of a horst-and-graben morphology, dated by conodonts and ammonoids as late Middle Anisian from overlying condensed limestones. In contrast to the well-known drowning event in the late Middle Anisian, precursor events to the final oceanic break-up of the Neo-Tethys have not yet been described, but play an important role in the reconstruction of the opening history of the Neo-Tethys. This knowledge gap is filled by the analysis of exactly datable sedimentary successions in the central Northern Calcareous Alps.

Several clinical studies have reported a double dissociation between abstract and concrete concepts, suggesting that they are processed by at least partly different networks in the brain. However, neuroimaging data seem not in line with neuropsychological reports. Using the ALE method, we run a meta-analysis on 32 brain-activation imaging studies that considered only nouns and verbs. Five clusters were associated with concrete words, four clusters with abstract words. When only nouns were selected three left activation clusters were found to be associated with concrete stimuli and only one with abstract nouns (left IFG). These results confirm that concrete and abstract words processing involves at least partially segregated brain areas, the IFG being relevant for abstract nouns and verbs while more posterior temporoparietal-occipital regions seem to be crucial for processing concrete words, in contrast with the neuropsychological literature that suggests a temporal anterior involvement for concrete words. We investigated the possible reasons that produce different outcomes in neuroimaging and clinical studies.

Identifying high-grade valuable wood resources by the visible individual traits of trees is a challenge for foresters and a requirement for sustainable resource management. The aim of this study was to identify the most relevant phenotypic descriptors of the acoustic quality of Norway spruce standing timber. Two highly valuable Norway spruce (Picea abies) stands located in the Romanian Carpathians were selected for this purpose. A total of 27 tree, bole, bark, and crown variables and nine variables related to wood structure were statistically checked against the velocities of stress waves measured on standing trees at breast height, and the derived parameters: the radiation, the impedance, and the moduli of elasticity in L and R directions. Principal component analysis was used for exploratory data analysis as well as mixed linear models were involved in explaining these acoustics. There were consistent variations in the measured acoustics from tree to tree, according to the age and social class. Wood acoustical parameters measured in the R direction are better predicted by tree phenotype than the acoustical parameters measured in the L direction. Bark thickness and branch width were the best predictors, while tree ring features were less predictive. At a given age, trees with high velocity had thinner and reddisher bark, thinner branches, and a narrower crown. Trees with high velocity anisotropy had narrower branches and wider sapwood. Furthermore, the phenotypic traits used had a poor explanatory power of the radiation ratio. In conclusion, spruce standing trees from the studied area bring forward certain outside features that enable us the multitrait identification of highly valuable wood for string instruments.

The aim of this article is to correlate the experimental modal analysis (EMA) with finite element analysis (FEA) to study the effect of wood species on vibration modes of violin plates made of spruce and maple. For EMA, five violin plates each made of spruce and maple were tested (curly maple, quilted maple, common maple with regular and irregular rings). The plates were clamped on edges and subjected to forced vibration. Experimental Chladni patterns of these plates were determined for 36 emitted frequencies, range between 65 and 2637 Hz. Patterns obtained with modal analysis are characterised by the nodal lines. The patterns of vibration modes are affected by wood species and structure. Spruce plate shows nodal lines aligned to the longitudinal (L) anisotropic direction of wood, corresponding to the direction of the fibres. Maple plates show nodal lines aligned to radial (R) anisotropic direction of wood and to the direction of medullary rays in the LR plane. Curly maple plate vibration produced the best resolution of vibration modes pattern, because of the presence of very abundant medullary rays, well oriented in the R direction. Quilted maple plate has asymmetric modes of vibration. At the highest frequency of 2093 Hz, no vibrating zones were observed during the experiment. Maple plates of normal structure with regular and irregular annual rings have shown similar patterns, but differ from curly maple plate. The characteristics of annual rings were measured. The vibrating surfaces (Sv) of the plates obtained experimentally were measured by transferring the nodal lines into AutoCAD 2013 software, where the surfaces were computed and expressed in mm2 or in % of the total surface area of the plate; the total effective vibrating surface for all frequencies for each plate and wood species; the relative vibrating surface at maximum amplitude. The experimental results were compared to modal analysis performed with FEA, by using ABAQUS program. The similar geometry of the real plates was generated in ABAQUS and the violin plates were meshed with quadratic shell elements. The plates were modelled as orthotropic materials. At maximum vibration amplitude and frequency of 110 Hz, the spruce plate has a relative vibrating surface of 62%, a mean annual ring width of 0.77 mm and ring heterogeneity of only 64%. At maximum amplitude of vibration and frequency of 174 Hz, the plates made of curly maple LR and LT (longitudinal–tangential), have different behaviour. The vibrating surface is greater for the plate made of curly maple LR with dense figures (84%) and annual ring heterogeneity of 86%, than for plates made of curly maple LT with large figures (77%) and annual ring heterogeneity of 238%.

Dental implants made of titanium covered with hydroxyapatite (Ti-HA) offer several advantages regarding mechanical, physicochemical, and biochemical aspects but lack stability in time, quality bone-bonding capabilities, or anticorrosion resistance in physiological media. In order to improve the characteristics of dental Ti-HA implants, we propose a new strategy for obtaining the deposited layer, consisting of the electrodeposition of the ceramic (HA) onto Ti metal followed by sintering of the ensemble at 600°C and then the electrodeposition of a second HA layer on top of the first one. The goal was to obtain a coating made up of two HA layers with a porosity gradient (one dense inner layer and one porous outer layer), and the results confirmed the formation of preferentially oriented, low-crystallinity double HA coatings. The base layer was made up of feathery crystals, and the top layer consisted of stellate clusters of crystals. Electrochemical tests, performed in artificial saliva solution at 37°C, showed that some HA coatings could moderately decrease the corrosion rate of Ti.

The present study aims to identify psychological factors affected by the COVID-19 pandemic given the information we have about reactions during previous pandemics, which documented features of anxiety, depression and post-traumatic stress disorder. We investigated the relationship between health anxiety, symptoms of depression, anxiety and stress, and coping mechanisms in the general population and among students. The study was conducted on Romanian population (n = 759), aged between 18–70 years old (M = 33.24), general population (n = 485), and students (n = 274). The results showed that the general population is more anxious when confronted with the new virus compared to students (t (757) = 1.902, p

Cane (Arundo donax L.) is the traditional material for reeds of woodwind musical instruments of classical symphony orchestra—clarinet, saxophone, oboe and bassoon. Cane is a natural material, and its structure is influenced by the growth conditions of the plant or by fungal attacks. The mode of vibration of reeds is affected by the quality of cane. In this article, physical, acoustical and mechanical properties of this material are described. These properties are characterized by a large natural variability. The physical properties of special interest are the swelling and the shrinkage of cane and the density (specific gravity). Mechanical properties of interest for the behavior of cane during playing are the elastic constants—moduli of elasticity and the corresponding parameters of internal friction. Acoustical properties are expressed by the velocity of propagation of elastic waves. The aging of reeds is due to various factors, among them are the repeated wet–dry and dry–wet cycles and the “continuous” playing. These factors modify the structural response of cane and have an irreversible effect on the quality of reeds. Statistical correlations between the quality of reeds and the descriptors of musical sounds are discussed. New synthetic materials of the group of polypropylenes have been developed for reeds having a better long-term behavior.

Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is a new technology for delivering intraperitoneal chemotherapy. It is generally assumed that with PIPAC, the ratio of peritoneal to systemic drug concentration is superior to liquid hyperthermic intraperitoneal chemotherapy (HIPEC). To date, no direct comparative data are available supporting such an assumption. Twelve 65-day-old pigs were randomly separated into three groups of four pigs each, all of which received intraperitoneal chemotherapy using the following administration methods: PIPAC with oxaliplatin 92 mg in 150 ml dextrose 5% (Group 1); PIPAC with electrostatic aerosol precipitation (ePIPAC; Group 2); or laparoscopic HIPEC (L-HIPEC) with oxaliplatin 400 mg in 4 L dextrose 5% at 42 °C (Group 3). Serial blood and peritoneal tissue concentrations of oxaliplatin were determined by spectrometry. In all three groups, the maximum concentration of oxaliplatin in blood was detected 50–60 min after onset of the chemotherapy experiments, with no significant differences among the three groups (p = 0.7994). Blood oxaliplatin concentrations (0–30 min) were significantly higher in the L-HIPEC group compared with the ePIPAC group (p

This paper is motivated by the study of the existence of optimal domains maximizing the kth Robin Laplacian eigenvalue among sets of prescribed measure, in the case of a negative boundary parameter. We answer positively to this question and prove an existence result in the class of measurable sets and for quite general spectral functionals. The key tools of our analysis rely on tight isodiametric and isoperimetric geometric controls of the eigenvalues. In two dimensions of the space, under simply connectedness assumptions, further qualitative properties are obtained on the optimal sets.

The purpose of this paper is to give some generalizations of de Branges Lemma for weighted spaces to obtain different approximation theorems in weighted spaces for algebras, vector subspaces or convex cones. We recall that the (original) de Branges Lemma (Proc Am Math Soc 10(5):822–824, 1959) was demonstrated for continuous scalar function on a compact space while, the weighted spaces are classes of continuous scalar functions on a locally compact space (e.g. the space of function with compact support, the space of bounded functions, the space of functions vanishing at infinity, the space of functions rapidly decreasing at infinity).

Objectives The study aims to generate the whole genome sequence of L. monocytogenes strain S2542 and to compare it to the genomes of strains RO15 and ScottA. In addition, we aimed to compare gene expression profiles of L. monocytogenes strains S2542, ScottA and RO15 after high-pressure processing (HPP) using ddPCR. Results The whole genome sequence of L. monocytogenes S2542 indicates that this strain belongs to serotype 4b, in contrast to the previously reported serotype 1/2a. Strain S2542 appears to be more susceptible to the treatment at 400 MPa compared to RO15 and ScottA strains. In contrast to RO15 and ScottA strains, viable cell counts of strain S2542 were below the limit of detection after HPP (400 MPa/8 min) when stored at 8 °C for 24 and 48 h. The transcriptional response of all three strains to HPP was not significantly different. Introduction Listeria monocytogenes is a gram-positive foodborne bacterium that can cause severe infections in humans. Listeriosis, the associated disease, particularly affects individuals with compromised immune systems [1] and may lead to hospitalization and mortality rates of 20–30% [2]. Humans are generally infected following consumption of contaminated ready-to-eat (RTE) food products that do not undergo thermal treatment during the manufacturing process or are contaminated post-thermal treatment. L. monocytogenes can thrive in a range of inhospitable environmental conditions including low temperatures thus causing significant challenge to the food industry [3,4,5,6]. Recently, we have studied the transcriptional response of L. monocytogenes strains RO15 and ScottA to HPP by RNA-seq [7, 8]. We observed that our previous gene expression results [8] are negatively correlated with the results of a previous study on HPP-induced changes in gene expression of L. monocytogenes strain S2542 [9]. Thus, our aim was to make a draft assembly of the genome of the strain S2542 (obtained from Tasmanian Institute of Agricultural Research) and to compare the genome sequences of these three strains. Based on the conflicting results regarding the HPP-induced changes in gene expression, we also performed a new set of HPP experiments under the same conditions as in our previous study [8] with all the three strains, and analyzed the transcriptional response of a number of representative genes.