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The concept of electronic orbitals has enabled the understanding of a wide range of physical and chemical properties of solids through the definition of, for example, chemical bonding between atoms. In the transmission electron microscope, which is one of the most used and powerful analytical tools for high‐spatial‐resolution analysis of solids, the accessible quantity is the local distribution of electronic states. However, the interpretation of electronic state maps at atomic resolution in terms of electronic orbitals is far from obvious, not always possible, and often remains a major hurdle preventing a better understanding of the properties of the system of interest. In this review, the current state of the art of the experimental aspects for electronic state mapping and its interpretation as electronic orbitals is presented, considering approaches that rely on elastic and inelastic scattering, in real and reciprocal spaces. This work goes beyond resolving spectral variations between adjacent atomic columns, as it aims at providing deeper information about, for example, the spatial or momentum distributions of the states involved. The advantages and disadvantages of existing experimental approaches are discussed, while the challenges to overcome and future perspectives are explored in an effort to establish the current state of knowledge in this field. The aims of this review are also to foster the interest of the scientific community and to trigger a global effort to further enhance the current analytical capabilities of transmission electron microscopy for chemical bonding and electronic structure analysis. [ABSTRACT FROM AUTHOR]

There have been numerous reports in the literature of diverse bacteria capable of degrading pentachlorophenol (PCP). In order to gain further insight into the phylogenetic relationships of PCP-degrading bacteria, we examined four strains: Arthrobacter sp. strain ATCC 33790, Flavobacterium sp. strain ATCC 39723, Pseudomonas sp. strain SR3, andSphingomonas sp. strain RA2. These organisms were isolated from different geographic allocations and all of them degrade high concentrations (100-200 mg/L) of PCP. Southern blot analyses determined that these bacteria all harbour DNA that encodes similar, if not identical, genes involved in PCP degradation. Comparison of the 16S rRNA nucleotide sequences revealed that these organisms were very closely related and, in fact, represent a monophyletic group. The 16S rRNA analyses together with fatty acid and sphingolipid analyses strongly suggest that the four strains are members of the genus Sphingomonas. The close relationship of the four organisms is supported by nucleotide sequence analysis data of the pcpB locus encoding PCP-4-monooxygenase, the first enzyme in the PCP degradative pathway. [ABSTRACT FROM AUTHOR]

In the present study we investigate the CoO/Co 3 O 4 interface in order to determine its intriguing magnetic behavior, which can be utilized for tailoring magnetic properties, enabling spin transport, enhancing magnetic coupling, tuning device functionalities, and realizing miniaturized magnetic devices for various technological applications. We decipher the magnetic properties of the CoO/Co 3 O 4 interface from first principles calculations using Wien2k and probe them experimentally by employing electron energy-loss magnetic chiral dichroism (EMCD), which is an electron-energy loss spectrometry (EELS) based technique in the transmission electron microscope (TEM). Both, theory and experiment, are in perfect agreement and result in a ferromagnetic 2D-electron gas of 5Å thickness directly at the interface., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

A new material characterization technique is emerging for the transmission electron microscope (TEM). Using electron energy-loss spectroscopy, real space mappings of the underlying electronic transitions in the sample, so called orbital maps, can be produced. Thus, unprecedented insight into the electronic orbitals responsible for most of the electrical, magnetic and optical properties of bulk materials can be gained. However, the incredibly demanding requirements on spatial as well as spectral resolution paired with the low signal-to-noise ratio severely limits the day-to-day use of this new technique. With the use of simulations, we strive to alleviate these challenges as much as possible by identifying optimal experimental parameters. In this manner, we investigate representative examples of a transition metal oxide, a material consisting entirely of light elements, and an interface between two different materials to find and compare acceptable ranges for sample thickness, acceleration voltage and electron dose for a scanning probe as well as for parallel illumination., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

All-solid-state Li-ion batteries are one of the most promising energy storage devices for future automotive applications as high energy density metallic Li anodes can be safely used. However, introducing solid-state electrolytes needs a better understanding of the forming electrified electrode/electrolyte interface to facilitate the charge and mass transport through it and design ever-high-performance batteries. This study investigates the interface between metallic lithium and solid-state electrolytes. Using spectroscopic ellipsometry, we detected the formation of the space charge depletion layers even in the presence of metallic Li. That is counterintuitive and has been a subject of intense debate in recent years. Using impedance measurements, we obtain key parameters characterizing these layers and, with the help of kinetic Monte Carlo simulations, construct a comprehensive model of the systems to gain insights into the mass transport and the underlying mechanisms of charge accumulation, which is crucial for developing high-performance solid-state batteries., (© 2023. The Author(s).)

Digital image comparison and matching brings many advantages over the traditional subjective human comparison, including speed and reproducibility. Despite the existence of an abundance of image difference metrics, most of them are not suited for high-resolution transmission electron microscopy (HRTEM) images. In this work we adopt two image difference metrics not widely used for TEM images. We compare them to subjective evaluation and to the mean squared error in regards to their behaviour regarding image noise pollution. Finally, the methods are applied to and tested by the task of determining precipitate sizes of a model material., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Thermal damage to the muscle layer during mucosal application of argon plasma coagulation (APC) may be avoided by creating a fluid cushion within the submucosal layer, but the minimum injection volume needed or the ideal injection fluid are yet to be established. We conducted a systematic ex vivo study with this aim., Methods: All experiments were performed in an ex vivo porcine gastrointestinal tract model. Five different fluids (saline, Glyceol, Gelafundin, Voluven, and Eleview) of different volumes were injected into the submucosa of different parts of the gastrointestinal tract. APC was applied to the mucosa at different power settings. Immediately after APC treatment, the temperature was measured through a thermocouple placed inside the fluid cushion, just on top of the muscle layer. The minimum volume of fluid needed to protect the muscle layer from thermal damage was determined., Results: There was no difference in the temperature measured among the different injection fluids at the surface of the muscle, in all the locations, at equal injection volumes and power settings. The minimum amounts of fluid needed to protect the muscle layer were 2 and 3 mL for power settings of 30-90 W and 90-120 W, respectively., Conclusions: Normal saline and 4 commercially available submucosal injection fluids possess similar thermal protective effects. To reduce the likelihood of thermal damage to deeper layers when APC is applied, a minimum injection volume of 3 mL is recommended if less than 90 W power will be utilized over 3 sec., Competing Interests: Conflict of Interest: Roberta Maselli, Paul J. Belletrutti, Marco Spadaccini, Piera Alessia Galteri, Milena Di Leo and Alessandro Repici have no conflicts of interest or financial ties to disclose; Thomas Stäbler, Michael Ederer, Alexander Neugebauer, Markus D. Enderle are employees at the Research Department of Erbe Elektromedizin GmbH, (Copyright: © Hellenic Society of Gastroenterology.)

Introduction: Recently, a new urodynamic method for the assessment of stress urinary incontinence called high definition urethral pressure profilometry (HD-UPP) has been introduced. This method combines a novel microtip catheter with advanced signal processing to enable spatial data location and the reconstruction of a pressure image inside the urethra. In order to assess the reproducibility of HD-UPP data, we statistically evaluate HD-UPP datasets and compare them to data from a double balloon air-charged system., Materials and Methods: Both catheters are used on sedated female minipigs. Data from the microtip catheter are processed through a signal reconstruction algorithm, urodynamic features are extracted, and compared to the air-charged system. Reproducibility of HD-UPP data is assessed by statistically evaluating consecutive, intra-individual datasets., Results: HD-UPP delivers results in agreement with previous comparisons of microtip and air-charged systems. The average deviation of two consecutive, intra-individual pressure images is very low at 7 cm H 2 O., Conclusions: HD-UPP provides physicians with detailed information on the pressure distribution inside the urethra. Through comparison with an air-charged catheter, it is shown that HD-UPP delivers results in agreement with previous studies on the comparison of microtip and air-charged catheters. It provides excellent reproducibility, as the difference between sequentially measured profiles from the same minipig is significantly lower than the one between profiles from different minipigs., (© 2016 Wiley Periodicals, Inc.)

Background: Bipolar vessel sealing is an efficient electrosurgical procedure for the occlusion of blood vessels particularly during minimally invasive surgery. Reliable knowledge of the thermal spread is crucial for a safe application of bipolar vessel sealing instruments when operating close to thermo-sensitive structures, such as nerves. The evolution of the thermal spread over time and space depends on a variety of parameters, such as the biological tissue, the energy applied to the tissue, and the geometry of the vessel sealing instrument. Mathematical modeling has proven useful for the prediction of the thermal spread. It is, thus, a promising tool for the systematic analysis of the influence of geometrical changes on the thermal spread., Results: We present an experimentally validated in silico study to evaluate the impact of geometry variations on the progression of chicken egg white coagulation and the final shape of coagulated egg white as an approximation of the temporal and spatial evolution of the thermal spread during bipolar vessel sealing. Egg white has similar thermal and electrical properties to human tissue, with the advantage being that the spatial and temporal evolution of the thermal spread can be visually gauged. The simulations were performed using a mathematical model based on the finite element analysis of chicken egg white. The progression of egg white coagulation was predicted for two different peak voltages and various electrode geometries. Starting with two planar electrodes, one electrode was gradually changed to adopt a wedge shape. These changes to the geometry showed a distinct influence on the progression of egg white coagulation in the simulations. The predictions were successfully validated using an experimental setup with two different electrodes representing the extreme geometries., Discussion: The predicted spatial temperature distributions were experimentally validated for two geometries. Our simulation study shows that the geometry has a pronounced influence on the thermal spread and, thus, is a suitable parameter to reduce thermal damage. The in silico optimization of instrument designs is a suitable tool to accelerate the development of new vessel sealing instruments, with only a few promising designs having to be tested as prototypes.

Background: A common method for reconstruction of the anterior cruciate ligament (ACL) is it's replacement by a free avascular graft, using the gracilis and/or semitendinosus tendons. These grafts pass a vulnerable phase in the ligamentization-process during the 1 st year after reconstruction. The aims of this study were first to evaluate the vascularization of the pes anserinus superficialis (PAS) by the inferior medial genicular artery (IMGA) and second to develop a pedunculated surgical technique for ACL reconstruction, to preserve a maximal amount of natural vascularization of the tendons inserting at the PAS., Materials and Methods: First, the vascularization of the PAS was assessed in 12 fresh-frozen lower extremities. The IMGA was identified at its origin at the popliteal artery and perfused with a methylene blue solution. Second, a pedunculated ACL reconstruction was performed in 5 fresh-frozen lower extremities under maintenance of the distal tendon insertion at PAS., Results: The PAS is a highly vascularized structure. Vessels originate from the IMGA, running along the three tendons of the PAS in the paratendinous tissue. Histologically intratendinous vessels exist; however, perfusion of the inserting tendons through intratendinous vessels was not proven macroscopically. The pedunculated grafts could be positioned and fixed successfully into the bone tunnels in all knees., Conclusion: Although intratendinous vascularization of the tendons of the PAS via the IMGA was not proven, this study indicates a new possibility of ACL reconstruction. The described operation technique can be conducive to shorten the vulnerable phase of the graft-ligamentization after ACL reconstruction., Competing Interests: There are no conflicts of interest.

Introduction: Urethral pressure profilometry (UPP) is used in the diagnosis of stress urinary incontinence (SUI). SUI is a significant medical, social, and economic problem, affecting about 12.5% of the population. A novel microtip catheter was developed for UPP featuring an inclination sensor and higher angular resolution compared to systems in clinical use today. Therewith, the location of each measured pressure sample can be determined and the spatial pressure distribution inside the urethra reconstructed. In order to assess the performance and plausibility of data from the microtip catheter, we compare it to data from a double balloon air charged system., Materials and Methods: Both catheters are used on sedated female minipigs. Data from the microtip catheter are processed through a signal reconstruction algorithm, plotted and compared against data from the air-charged catheter., Results: The microtip catheter delivers results in agreement with previous comparisons of microtip and air-charged systems. It additionally provides a new level of detail in the reconstructed UPPs which may lead to new insights into the sphincter mechanism of minipigs., Conclusions: The ability of air-charged catheters to measure pressure circumferentially is widely considered a main advantage over microtip catheters. However, directional pressure readings can provide additional information on angular fluctuations in the urethral pressure distribution. It is shown that the novel microtip catheter in combination with a signal reconstruction algorithm delivers plausible data. It offers the opportunity to evaluate urethral structures, especially the sphincter, in context of the correct location within the anatomical location of the pelvic floor. Neurourol. Urodynam. 35:888-894, 2016. © 2015 Wiley Periodicals, Inc., (© 2015 Wiley Periodicals, Inc.)

Macrophages are cells with remarkable plasticity. They integrate signals from their microenvironment leading to context-dependent polarization into classically (M1) or alternatively (M2) activated macrophages, representing two extremes of a broad spectrum of divergent phenotypes. Thereby, macrophages deliver protective and pro-regenerative signals towards injured tissue but, depending on the eliciting damage, may also be responsible for the generation and aggravation of tissue injury. Although incompletely understood, there is emerging evidence that macrophage polarization is critical for these antagonistic roles. To identify activation-specific expression patterns of chemokines and cytokines that may confer these distinct effects a systems biology approach was applied. A comprehensive literature-based Boolean model was developed to describe the M1 (LPS-activated) and M2 (IL-4/13-activated) polarization types. The model was validated using high-throughput transcript expression data from murine bone marrow derived macrophages. By dynamic modeling of gene expression, the chronology of pathway activation and autocrine signaling was estimated. Our results provide a deepened understanding of the physiological balance leading to M1/M2 activation, indicating the relevance of co-regulatory signals at the level of Akt1 or Akt2 that may be important for directing macrophage polarization.

Background: Urethral pressure profilometry (UPP) is used in the diagnosis of stress urinary incontinence (SUI) which is a significant medical, social, and economic problem. Low spatial pressure resolution, common occurrence of artifacts, and uncertainties in data location limit the diagnostic value of UPP. To overcome these limitations, high definition urethral pressure profilometry (HD-UPP) combining enhanced UPP hardware and signal processing algorithms has been developed. In this work, we present the different signal processing steps in HD-UPP and show experimental results from female minipigs., Methods: We use a special microtip catheter with high angular pressure resolution and an integrated inclination sensor. Signals from the catheter are filtered and time-correlated artifacts removed. A signal reconstruction algorithm processes pressure data into a detailed pressure image on the urethra's inside. Finally, the pressure distribution on the urethra's outside is calculated through deconvolution. A mathematical model of the urethra is contained in a point-spread-function (PSF) which is identified depending on geometric and material properties of the urethra. We additionally investigate the PSF's frequency response to determine the relevant frequency band for pressure information on the urinary sphincter., Results: Experimental pressure data are spatially located and processed into high resolution pressure images. Artifacts are successfully removed from data without blurring other details. The pressure distribution on the urethra's outside is reconstructed and compared to the one on the inside. Finally, the pressure images are mapped onto the urethral geometry calculated from inclination and position data to provide an integrated image of pressure distribution, anatomical shape, and location., Conclusions: With its advanced sensing capabilities, the novel microtip catheter collects an unprecedented amount of urethral pressure data. Through sequential signal processing steps, physicians are provided with detailed information on the pressure distribution in and around the urethra. Therefore, HD-UPP overcomes many current limitations of conventional UPP and offers the opportunity to evaluate urethral structures, especially the sphincter, in context of the correct anatomical location. This could enable the development of focal therapy approaches in the treatment of SUI.

The coccolithophorid unicellular alga Emiliania huxleyi is known to form large blooms, which have a strong effect on the marine carbon cycle. As a photosynthetic organism, it is subjected to a circadian rhythm due to the changing light conditions throughout the day. For a better understanding of the metabolic processes under these periodically-changing environmental conditions, a genome-scale model based on a genome reconstruction of the E. huxleyi strain CCMP 1516 was created. It comprises 410 reactions and 363 metabolites. Biomass composition is variable based on the differentiation into functional biomass components and storage metabolites. The model is analyzed with a flux balance analysis approach called diurnal flux balance analysis (diuFBA) that was designed for organisms with a circadian rhythm. It allows storage metabolites to accumulate or be consumed over the diurnal cycle, while keeping the structure of a classical FBA problem. A feature of this approach is that the production and consumption of storage metabolites is not defined externally via the biomass composition, but the result of optimal resource management adapted to the diurnally-changing environmental conditions. The model in combination with this approach is able to simulate the variable biomass composition during the diurnal cycle in proximity to literature data.