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Funding Information: German Research Foundation grant RA2832/1-1 (P.R., J.H.); Universität Osnabrück, Innovationspool (P.R., J.H.); World Premier International Research Center Initiative (WPI), MEXT, Japan (ASF); Academy of Finland project no. 314862 (Y.S.R., O.K., A.S.F.). Publisher Copyright: © 2023 American Chemical Society. Calcite, in the natural environment the most stable polymorph of calcium carbonate (CaCO3), not only is an abundant mineral in the Earth’s crust but also forms a central constituent in the biominerals of living organisms. Intensive studies of calcite(104), the surface supporting virtually all processes, have been performed, and the interaction with a plethora of adsorbed species has been studied. Surprisingly, there is still serious ambiguity regarding the properties of the calcite(104) surface: effects such as a row-pairing or a (2 × 1) reconstruction have been reported, yet so far without physicochemical explanation. Here, we unravel the microscopic geometry of calcite(104) using high-resolution atomic force microscopy (AFM) data acquired at 5 K combined with density functional theory (DFT) and AFM image calculations. A (2 × 1) reconstruction of a pg-symmetric surface is found to be the thermodynamically most stable form. Most importantly, a decisive impact of the (2 × 1) reconstruction on adsorbed species is revealed for carbon monoxide.

openaire: EC/H2020/788185/EU//E-DESIGN | openaire: EC/H2020/845060/EU//QMKPFM | openaire: EC/H2020/897828/EU//EIM While offering high resolution atomic and electronic structure, scanning probe microscopy techniques have found greater challenges in providing reliable electrostatic characterization on the same scale. In this work, we offer electrostatic discovery atomic force microscopy, a machine learning based method which provides immediate maps of the electrostatic potential directly from atomic force microscopy images with functionalized tips. We apply this to characterize the electrostatic properties of a variety of molecular systems and compare directly to reference simulations, demonstrating good agreement. This approach offers reliable atomic scale electrostatic maps on any system with minimal computational overhead.

Substituting carbon with silicon in organic molecules and materials has long been an attractive way to modify their electronic structure and properties. Silicon-doped graphene-based materials are known to exhibit exotic properties, yet conjugated organic materials with atomically precise Si substitution have remained difficult to prepare. Here we present the on-surface synthesis of one- and two-dimensional covalent organic frameworks whose backbones contain 1,4-disilabenzene (C4Si2) linkers. Silicon atoms were first deposited on a Au(111) surface, forming a AuSix film on annealing. The subsequent deposition and annealing of a bromo-substituted polyaromatic hydrocarbon precursor (triphenylene or pyrene) on this surface led to the formation of the C4Si2-bridged networks, which were characterized by a combination of high-resolution scanning tunnelling microscopy and photoelectron spectroscopy supported by density functional theory calculations. Each Si in a hexagonal C4Si2 ring was found to be covalently linked to one terminal Br atom. For the linear structure obtained with the pyrene-based precursor, the C4Si2 rings were converted into C4Si pentagonal siloles by further annealing.

The V4 countries went through a transformation of their entire economies, including the agricultural sector, in the 1990s. Each of these countries approached the transformation of agriculture differently, but later the V4 countries’ approach to agricultural development was unified by the EU's common agricultural policy. The aim of the paper was to compare the development of the production (sown area and hectare yield) of selected most commonly cultivated crops in Slovak and Czech regions (NUTS 3) in the period between 2004 and 2017. The development of production in these two countries was also evaluated against the trends of V4 countries. Based on these analyses, common and specific agriculture development trends in V4 countries were revealed. A chronological average was used to evaluate the average values of the monitored indicators in the period from 2004 to 2017 in Slovak and Czech regions. To express the development of the given indicators between 2004 and 2017, the change index was used and visualised cartographically. Regression analysis was used to show the development trends of agricultural production in the V4 countries. In general, the agricultural sectors in the V4 countries show similar characteristics with similar trends, and the average hectare yield has a modest growing trend. In terms of the structure of the cultivated plants, the size of the cultivated areas, the volume of production and the average hectare yields, there have been considerable changes to crop farming in Slovak and Czech regions. The study showed that the changes in the agrarian sector after the year 2004 conditioned by the entry of Czechia and Slovakia into the European Union were reflected in a decrease in crop production and an increase in regional disparities. From the point of view of the production indicator expressing the hectare yield of crops, Czechia achieves better indicator values than does Slovakia.

The authors present the unusual case of a 15-year-old boy with a primary empty sella caused by non-communicating hydrocephalus due to fourth ventricle outflow obstruction whose secondary symptoms of growth hormone deficiency and delayed puberty were successfully treated by endoscopic third ventriculocisternostomy (ETV). Hypopituitarism occurs only rarely in cases of hydrocephalus; rarer still are cases where hypopituitarism is the sole symptom of hydrocephalus. A primary empty sella may indicate elevated intracranial pressure; if the cause is non-communicating hydrocephalus, ETV is indicated as the preferred treatment modality.

Introduction. Pyocephalus always presents serious complications in the treatment of brain abscesses, and is associated with high rates of mortality and morbidity. This study aimed to comprehensively evaluate this understandably feared complication from a purely medical perspective by using an evidence-based approach and drawing comparisons from the available literature, which mostly comprises case reports. Methods. This was a prospective monocentric study of all patients treated for brain abscesses at the Neurosurgery Clinic of the University Hospital Ostrava between 2012 and 2017. The cohort was divided into two groups for statistical comparison; one group comprised those in which pyocephalus occurred before or during treatment, while the other group comprised patients without this complication. Particular consideration was given to the effect of pyocephalus on morbidity and mortality rates and C-reactive protein levels, as well as to the identification of risk factors, and to its possible therapeutic influence. Patients were followed up for six months. Results. A total of 43 patients were treated for a brain abscess. An unequivocal diagnosis of pyocephalus was established via CT and MRI brain scans in five cases (11.6%). In the cohort as a whole, mortality and morbidity rates were 23.3% and 48.8% respectively. Among patients with pyocephalus the incidence of mortality and morbidity was 40% and 66.6% respectively. The presence of pyocephalus is not a significant predictor of either morbidity (p 0.575) or mortality (p 0.664). In patients with pyocephalus, we determined elevated CRP levels on the day of surgery (p 0.038). The occurrence of epileptic seizures in the acute phase of the disease is associated with a poor outcome (p 0.039). Conclusions. Pyocephalus will continue to be a serious complication in the treatment of brain abscesses, although we were unable to determine its utility as a prognostic factor. Patients with this complication have elevated CRP levels on the day of operation.

openaire: EC/H2020/788185/EU//E-DESIGN | openaire: EC/H2020/839242/EU//EMOF | openaire: EC/H2020/845060/EU//QMKPFM Achieving large-area uniform 2D metal-organic frameworks (MOFs) and controlling their electronic properties on inert surfaces is a big step toward future applications in electronic devices. Here a 2D monolayer Cu-dicyanoanthracene MOF with long-range order is successfully fabricated on an epitaxial graphene surface. Its structural and electronic properties are studied by low-temperature scanning tunneling microscopy and spectroscopy complemented by density-functional theory calculations. Access to multiple molecular charge states in the 2D MOF is demonstrated using tip-induced local electric fields. It is expected that a similar strategy could be applied to fabricate and characterize 2D MOFs with exotic, engineered electronic states.

openaire: EC/H2020/839242/EU//EMOF | openaire: EC/H2020/845060/EU//QMKPFM | openaire: EC/H2020/788185/EU//E-DESIGN The quest for planar sp2-hybridized carbon allotropes other than graphene, such as graphenylene and biphenylene networks, has stimulated substantial research efforts because of the materials’ predicted mechanical, electronic, and transport properties. However, their syntheses remain challenging given the lack of reliable protocols for generating nonhexagonal rings during the in-plane tiling of carbon atoms. We report the bottom-up growth of an ultraflat biphenylene network with periodically arranged four-, six-, and eight-membered rings of sp2-hybridized carbon atoms through an on-surface interpolymer dehydrofluorination (HF-zipping) reaction. The characterization of this biphenylene network by scanning probe methods reveals that it is metallic rather than a dielectric. We expect the interpolymer HF-zipping method to complement the toolbox for the synthesis of other nonbenzenoid carbon allotropes.

In this study, aramid fiber-reinforced polymer (AFRP) composites were prepared and then postcured under specific heating/cooling rates. By dynamic mechanical analysis, the viscoelastic properties of the AFRP composites at elevated temperatures and under various frequencies were determined. Thermomechanical analysis (TMA), in the modes of creep-recovery and stress-relaxation tests, was also performed. Furthermore, differential scanning calorimetry was also used, and the decomposition of the AFRP composites, aramid fibers, and pure postcured epoxy, in two different atmospheres, namely, air atmosphere and nitrogen (N2) atmosphere, was explored by the thermogravimetric analysis (TGA). From this point of view, the aramid fibers showed remarkably thermal resistance, in N2 atmosphere, and the volume fraction of fibers (φf) was calculated to be φf = 51%. In the TGA experiments, the postcured AFRP composites showed very good thermal resistance, both in air and N2 atmosphere, and this characteristic in conjunction with their relatively high Tg, which is in the range of 85-95°C, depending on the frequency and the determination method, classifies these composites as potential materials in applications where the resistance in high temperatures is a required characteristic. © 2021 Konstantinos Karvanis et al., published by De Gruyter 2021., TBU in Zlin [IGA/FT/2021/006], IGA/FT/2021/006

Controlling the properties of organic/inorganic materials requires detailed knowledge of their molecular adsorption geometries. This is often unattainable, even with current state-of-the-art tools. Visualizing the structure of complex non-planar adsorbates with atomic force microscopy (AFM) is challenging, and identifying it computationally is intractable with conventional structure search. In this fresh approach, cross-disciplinary tools are integrated for a robust and automated identification of 3D adsorbate configurations. Bayesian optimization is employed with first-principles simulations for accurate and unbiased structure inference of multiple adsorbates. The corresponding AFM simulations then allow fingerprinting adsorbate structures that appear in AFM experimental images. In the instance of bulky (1S)-camphor adsorbed on the Cu(111) surface, three matching AFM image contrasts are found, which allow correlating experimental image features to distinct cases of molecular adsorption., Comment: 9 pages, 4 figures, 1 table

Heterocyclic [8]circulenes are an important class of polycyclic aromatic hydrocarbon molecules because of their unique structural properties and promising applications. However, the synthesis of heterocyclic [8]circulenes is still limited and thus is an important synthetic challenge. Here we describe the first example of a π-extended diaza[8]circulene surrounded by and fused with six hexagons and two pentagons, which was successfully synthesized only by a combined in-solution and on-surface synthetic strategy. State-of-the-art scanning tunneling microscopy with a CO-functionalized tip and density functional theory calculations revealed its planar conformation and unique electronic structure. Ministry of Education (MOE) Nanyang Technological University This work was supported in part by Nanyang Technological University (S.I.), the Singapore Ministry of Education via Academic Research Fund Tier 1:2018-T1-002-021 (S.I.), and Japan Society for the Promotion of Science (JSPS) through KAKENHI Grant 19H00856 (S.K.). K.N. thanks NTU for the SPMS International Internship Program. O.K. was supported by the European Union’s Horizon 2020 Research and Innovation Programme under Marie Skłodowska-Curie Grant Agreement 845060. A.S.F. was supported by the World Premier International Research Center Initiative (WPI), MEXT, Japan. Computing resources from the Aalto ScienceIT Project and CSC, Helsinki, are gratefully acknowledged. S.K. sincerely thanks Prof. Ernst Meyer, Dr. Urs Gysin, Mr. Sascha Martin, and Mr. Yves Pellmont for their support to build the low-temperature ultrahigh-vacuum atomic force microscopy/scanning tunneling microscopy system. S.I. sincerely thanks Prof. Rei Kinjo and Ms. Kei Ota (NTU) for ACID analysis and Prof. Naoki Aratani (NAIST) for the fruitful discussion during the preparation of this Communication.

Prospective randomized data is currently lacking which compares endoscopically assisted surgery with open surgical techniques in the treatment of cubital tunnel syndrome (CUTS). The aim of this study is to compare patient outcome in both techniques.This prospective study comprised of 45 patients who, between October 2014 and February 2017, were randomly assigned to undergo either endoscopic or open surgery (22 and 23 patients respectively) for decompression of the ulnar nerve. Patients were followed up at 3 and 12 months postoperation. McGowan classification was used to determine the severity of symptoms. Surgical outcome was evaluated by Bishop classification. Pain levels were monitored according to gender from 0 to 10 days postoperation. Other factors investigated were chronic scar pain, working status, operation duration, and patient satisfaction regarding postoperative scarring and the procedure itself.Both methods are equally effective in the treatment of CUTS (Bishop score excellent or good 90% vs 96%). Postoperative pain is significant particularly in the first few days following surgery, but with no significant difference depending on procedure. In the open group, postoperative pain was significantly higher in women than in men; pain did not differ between the sexes in the endoscopic group. The tendency to lower levels of pain among endoscopically operated women in comparison with women in the open group was not statistically notable. Patients who underwent open decompression experienced notably higher levels of postoperative chronic scar pain. Although working status and satisfaction with the surgical outcome were the same in both groups, satisfaction with scarring was higher in the endoscopy group. Operation time was significantly longer by endoscopy.Both studied methods produced equal satisfactory outcomes in the treatment of CUTS. Endoscopy has the potential to minimize chronic scar pain and improve scarring esthetics, at the expense of longer operating time.Supported by Ministry of Health, Czech Republic-conceptual development of research organization (FNOs/2014, project number 20). Graphical abstract Median postoperative pain from 0 to 10 days by group.

Homopolymerizations of 2,5-diethynylthiophene into conjugated microporous polymers by (i) chain-growth polymerization and (ii) polycyclotrimerization are described. Both methods provide nearly quantitative yields of thiophene-rich (7.6 mmol thiophene rings/g) networks with specific surface area up to 839 m2/g. The thiophene units enhance the affinity of the networks to CO2 and red-shift the UV/vis and fluorescence absorption and emission bands of the networks, respectively.

Graphene nanoribbons are one of the most promising materials for nanoscale electronics. While various structures have successfully been synthesized by on-surface reactions, curved connections remain less investigated, yet they could prove highly useful in the development of copolymerization technology. Here, we present the synthesis of three different regioisomeric junctions on Au (111) by using 10,10'-dibromo-9,9'-bianthryl and 1,3,6,8-tetrabromopyrene. The chemical structures and the electronic properties of junctions were studied with a combination of scanning tunneling microscopy with a CO terminated tip, scanning tunneling spectroscopy, and density functional theory calculations. We found that two identical nanoribbon-junction interface electronic states appear within the band gaps of connected graphene nanoribbons.

In this study, basalt fiber-reinforced polymer (BFRP) composites with epoxy matrix, 20 layers, and volume fraction of fibers Vf = 53.66%, were prepared by a hand lay-up compression molding combined method. The fabric of the basalt fibers is in twill 2/2 weave. Through dynamic mechanical analysis (DMA), their viscoelastic behavior at elevated temperatures and in various frequencies was explored, whereas thermomechanical analysis (TMA) took part in terms of creep recovery and stress-relaxation tests. Moreover, the glass transition temperature (Tg) of the BFRP composites was determined through the peak of the tan&delta, curves while the decomposition of the BFRP composites and basalt fibers, in air or nitrogen atmosphere, was explored through thermogravimetric analysis (TGA). The mechanical behavior of the BFRP composites was investigated by tensile and three-point bending experiments. The results showed that as the frequency is raised, the BFRP composites can achieve slightly higher Tg while, under the same circumstances, the storage modulus curve obtains a less steep decrease in the middle transition region. Moreover, the hand lay-up compression molding hybrid technique can be characterized as efficient for the preparation of polymer matrix composites with a relatively high Vf of over 50%. Remarkably, through the TGA experiments, the excellent thermal resistance of the basalt fibers, in the temperature range 30&ndash, 900 &deg, C, was revealed.

This paper deals with the influence of a major economic entity on the development of a municipality / region in which it operates. Specifically, it is a case study of a female prison in Světla nad Sazavou, which is a specific example because it also contains a security issue. The aim of the paper is, firstly, to identify the influences of the prison on the municipality / region and, secondly, to evaluate the attitudes of the population of the municipality towards the prison. To meet the first aim, an analysis of publicly available information on the prison was used and a semi-structured interview with a prison management was done, in the case of the second aim, a questionnaire survey was conducted among the locals older than 15 years. The prison is the second most important employer in the municipality, the source of a relatively cheap labour force for local businesses. Locals also appreciate the use of the former school in nature, more than 90% of the municipality's population feel safe. Only less than a fifth of the population rate the prison's presence negatively. In general, the attitude of the population can be described as neutral positive.

Nitrogen doping of graphene significantly affects its chemical properties, which is particularly important in molecular sensing and electrocatalysis applications. However, detailed insight into interaction between N-dopant and molecules at the atomic scale is currently lacking. Here we demonstrate control over the spin state of a single iron(II) phthalocyanine molecule by its positioning on N-doped graphene. The spin transition was driven by weak intermixing between orbitals with z-component of N-dopant (pz of N-dopant) and molecule (dxz, dyz, dz2) with subsequent reordering of the Fe d-orbitals. The transition was accompanied by an electron density redistribution within the molecule, sensed by atomic force microscopy with CO-functionalized tip. This demonstrates the unique capability of the high-resolution imaging technique to discriminate between different spin states of single molecules. Moreover, we present a method for triggering spin state transitions and tuning the electronic properties of molecules through weak non-covalent interaction with suitably functionalized graphene., Molecules can change their electronic properties when they are adsorbed on substrates, which can be useful for sensing and catalysis. Here, the authors use atomic force microscopy to show that the spin state of an iron complex can be changed upon displacing the molecule to different sites of a nitrogen-doped graphene

Here we show scanning tunneling microscopy (STM), noncontact atomic force microscopy (AFM), and inelastic electron tunneling spectroscopy (IETS) measurements on an organic molecule with a CO-terminated tip at 5 K. The high-resolution contrast observed simultaneously in all channels unambiguously demonstrates the common imaging mechanism in STM/AFM/IETS, related to the lateral bending of the CO-functionalized tip. The IETS spectroscopy reveals that the submolecular contrast at 5 K consists of both renormalization of vibrational frequency and variation of the amplitude of the IETS signal. This finding is also corroborated by first principles simulations. We extend accordingly the probe-particle AFM/STM/IETS model to include these two main ingredients necessary to reproduce the high-resolution IETS contrast. We also employ the first principles simulations to get more insight into a different response of frustrated translation and rotational modes of the CO tip during imaging.

The journal of physical chemistry letters 8(16), 3820 - 3825(2017). doi:10.1021/acs.jpclett.7b01549, The direct elucidation of the reaction pathways in heterogeneous catalysis has been challenging due to the short-lived nature of reaction intermediates. Here, we directly measured on ultrafast time scales the initial hydrogenation steps of adsorbed CO on a Ru catalyst surface, which is known as the bottleneck reaction in syngas and CO$_2$ reforming processes. We initiated the hydrogenation of CO with an ultrafast laser temperature jump and probed transient changes in the electronic structure using real-time X-ray spectroscopy. In combination with theoretical simulations, we verified the formation of CHO during CO hydrogenation., Published by ACS, Washington, DC

We investigate the development of the local bonding and chemical state of boron atoms during the growth of B-doped graphene on $6H\text{\ensuremath{-}}\mathrm{SiC}(0001)$. Photoemission experiments reveal the presence of two chemical states, namely, boron in the uppermost SiC bilayers and boron substituted in both the graphene and buffer layer lattices. We demonstrate the participation of the dopant in the $\ensuremath{\pi}$ electron system of graphene by the presence of the ${\ensuremath{\pi}}^{*}$ resonance in the near edge x-ray adsorption fine structure (NEXAFS) recorded at the B $K$-edge. The experimental findings are supported by NEXAFS simulations.

The authors have observed anomalous structural evolution of a clean Si(111) surface, which was prepared first by thallium (Tl) deposition on a Si(111)7 × 7 surface, leading to incomplete formation of a Tl/Si(111)1 × 1 structure at 300 °C and subsequent desorption of Tl at 350 °C. Thus prepared clean Si(111) surfaces exhibit structural changes with increase of temperature: 2×1→(3×3)R30°→2×1→5×5→7×7, as observed by low-energy electron diffraction and scanning tunneling microscopy. Among the above structures, the (3×3)R30° formed at 450–550 °C is found not to be a simple adatom structure. Instead, by means of ab-initio calculations a new metastable (3×3)R30° reconstruction was found, having analogous structural features and formation origin to a 2 × 1 reconstruction known as the Pandey chain model. This new (3×3)R30° model is 0.09 eV per surface atom less favorable than the 2 × 1 reconstruction. A reason for the anomalous occurrence of the (3×3)R30° structure is explored with an aid of Monte Carlo simulations.

TCR gene rearrangement generates diversity of T lymphocytes by V(D)J recombination. Ig genes are rearranged in B cells using the same enzyme machinery. TCRD (TCR δ) genes are frequently incompletely rearranged in B precursor leukemias and recently were found in a significant portion of physiological B lymphocytes. Incomplete TCRD rearrangements (V-D) thus serve as natural indicators of previous V(D)J recombinase activity. Functional V(D)J recombinase has recently been found in murine NK precursors. We tested whether physiological NK cells and other leukocyte subpopulations contained TCR rearrangements in humans. This would provide evidence that V(D)J recombinase was active in the ancestry cells and suggest common pathways among the positive cell types. TCRD were rearranged in 3.2–36% of NK cells but not in nonlymphoid leukocytes. The previously known phenomenon of TCRD transcription in NK cells is a possible mechanism that maintains the chromatin open at the TCRD locus. In comparison, TCRG rearrangements were frequent in T cells, low to negative in B and NK cells, and negative in nonlymphoid cells, suggesting a tighter control of TCRG. Levels of TCRD rearrangements were similar among the B lymphocyte subsets (B1-B2, naive-memory). In conclusion, human NK cells pass through a differentiation step with active V(D)J recombinase similar to T and B lymphocytes and unlike nonlymphoid leukocytes. This contradicts recent challenges to the concept of separate lymphoid and myeloid differentiation.

Manuscript describes producing keratin hydrolysate from sheep wool through two-stage technology whose principle consists in first having wool processed in an alkaline environment during the first stage, and then effecting hydrolysis in the second stage through the action of proteolytic enzyme. Experiments were planned in accordance with factor schemes of 23 types in which factors under study were influence of first stage hydrolysis duration (6-24 hours), duration of hydrolysis second stage (6-24 hours) and quantity of added proteolytic enzyme (1-5 %) on quantity of decomposed wool., Operational Program Research and Development for InnovationsEuropean Commission; European Regional Development Fund (ERDF)European Commission; national budget of the Czech Republic, within the framework of project Centre of Polymer Systems [CZ.1.05/2.1.00/03.0111]; TBU in Zlin - resources of specific university research [IGA/11/FT/11/D]