Biocompatible surface functionalization architecture for a diamond quantum sensor.

Quantum metrology enables some of the most precise measurements. In the life sciences, diamond-based quantum sensing has led to a new class of biophysical sensors and diagnostic devices that are being investigated as a platform for cancer screening and ultrasensitive immunoassays. However, a broader application in the life sciences based on nanoscale NMR spectroscopy has been hampered by the need to interface highly sensitive quantum bit (qubit) sensors with their biological targets. Here, we demonstrate an approach that combines quantum engineering with single-molecule biophysics to immobilize individual proteins and DNA molecules on the surface of a bulk diamond crystal that hosts coherent nitrogen vacancy qubit sensors. Our thin (sub-5 nm) functionalization architecture provides precise control over the biomolecule adsorption density and results in near-surface qubit coherence approaching 100 µs. The developed architecture remains chemically stable under physiological conditions for over 5 d, making our technique compatible with most biophysical and biomedical applications.

A modified integrated physical advanced primary treatment to enhance particulate organic carbon removal in municipal wastewater treatment plants.

In the pursuit of a treatment approach that is both cost-effective and environmental-friendly, the applicability of microscreen (MS) techniques coupled with a primary sedimentation tank (PST) as a physical advanced primary treatment (APT) to enhance the removal of particulate organic carbon (POC) from municipal wastewater was investigated. A pilot unit, including a modified MS, adjustable to different meshes (including 20 and 15 µm) was operated continuously downstream to the PST at the Büsnau wastewater treatment plant in Stuttgart, Germany, and monitored for more than half a year. A strategy involving time-dependent backwashing and recirculation of MS permeate was employed to remove as much POC as possible from primarily treated wastewater, thereby extending the application of the MS. The optimal configuration, PST + 15-µm MS, achieved maximum removal efficiencies of 90% for turbidity, 90% for total suspended solids (TSS), and 80% for total chemical oxygen demand (TCOD). These results are significant, as comparable removal levels for these parameters were conventionally achieved using less eco-friendly methods such as physiochemical APT, including coagulation-flocculation with iron or aluminum salts followed by microscreening or sedimentation. However, this study's findings ascertained that solo physical APT applications could produce equivalent effluent quality with a much smaller footprint while keeping the advanced primary treated wastewater suitable for biological treatment.

Probing and manipulating embryogenesis via nanoscale thermometry and temperature control.

Understanding the coordination of cell-division timing is one of the outstanding questions in the field of developmental biology. One active control parameter of the cell-cycle duration is temperature, as it can accelerate or decelerate the rate of biochemical reactions. However, controlled experiments at the cellular scale are challenging, due to the limited availability of biocompatible temperature sensors, as well as the lack of practical methods to systematically control local temperatures and cellular dynamics. Here, we demonstrate a method to probe and control the cell-division timing in Caenorhabditis elegans embryos using a combination of local laser heating and nanoscale thermometry. Local infrared laser illumination produces a temperature gradient across the embryo, which is precisely measured by in vivo nanoscale thermometry using quantum defects in nanodiamonds. These techniques enable selective, controlled acceleration of the cell divisions, even enabling an inversion of division order at the two-cell stage. Our data suggest that the cell-cycle timing asynchrony of the early embryonic development in C. elegans is determined independently by individual cells rather than via cell-to-cell communication. Our method can be used to control the development of multicellular organisms and to provide insights into the regulation of cell-division timings as a consequence of local perturbations.

Depolarization Dynamics in a Strongly Interacting Solid-State Spin Ensemble.

We study the depolarization dynamics of a dense ensemble of dipolar interacting spins, associated with nitrogen-vacancy centers in diamond. We observe anomalously fast, density-dependent, and nonexponential spin relaxation. To explain these observations, we propose a microscopic model where an interplay of long-range interactions, disorder, and dissipation leads to predictions that are in quantitative agreement with both current and prior experimental results. Our results pave the way for controlled many-body experiments with long-lived and strongly interacting ensembles of solid-state spins.

Accessing osteocyte lacunar geometrical properties in human jaw bone on the submicron length scale using synchrotron radiation µCT.

The architectural properties of the osteocyte cell network provide a valuable basis for understanding the mechanisms of bone remodelling, mineral homeostasis, ageing and pathologies. Recent advances in synchrotron microtomography enable unprecedented three-dimensional imaging of both the bone lacunar network and the extracellular matrix. Here, we investigate the three-dimensional morphological properties of osteocyte lacunae in human healthy and bisphosphonate-related osteonecrotic jaw bone based on synchrotron X-ray computed tomography images, with a spatial isotropic voxel size of 300 nm. Bisphosphonate-related osteonecrosis of the jaw is a relatively new disease with increasing incidence, which remains poorly understood. A step forward in elucidating this malady is to assess whether, and how, the morphology of the osteocyte lacunar network is modified in the affected jaw tissue. We evaluate thousands of cell lacunae from five specimens of which three originate from patients diagnosed with bisphosphonate-associated osteonecrosis. In this exploratory study, we report three-dimensional quantitative results on lacunar volumes (296-502 µm(3)), shape (approximated by an ellipsoidal shape with principal axes a > b > c, such that a = 2.2b and a = 4c) and spatial distribution (i.e., 50% of the mineralized matrix volume is located within 12 µm to the closest lacunar boundary) at submicron resolution on such specimens. We observe that the average lacunar volumes of the bisphosphonate-related osteonecrotic jaw specimens were within the range of volumes found in the two specimens originating from healthy donors and conclude that lacunar volumes are not the key element in the course of bisphosphonate-related osteonecrotic jaw. In three out of five specimens we observe lacunar volume sizes in segmented osteons to be significantly different compared to lacunar volumes in the adjacent tissue regions. Furthermore, we quantify the number of lacunae containing small dense objects (on average 9%). In contrast to lacunar morphology we report the lacunar density (16,000-50,000 per mm(3)) to be different in jaw bone tissue compared to what has been reported in femoral sites.

An integrated physical-chemical system for concurrent carbon, nitrogen, and phosphorus removal in municipal wastewater treatment plants.

A substantial quantity of suspended solids (SS) present in municipal wastewater leads to the swift depletion of the ion exchange (IE) capacity of natural zeolites like Clinoptilolite (CIO). This limitation has become the primary factor contributing to the limited adoption of the IE technique within municipal wastewater treatment plants (WWTPs). However, an extensive lab-scale and pilot-scale study conducted over approximately one year has made it possible to efficiently apply the IE system using CIO (main grain size of 0.5-1.0 mm) upstream of the primary sedimentation tank (PST). The primary treated wastewater (PTWW) was introduced to the IE system either by pre-straining or without any pre-treatment. The IE system's capabilities for removing total suspended solids (TSS), chemical oxygen demand (COD), and phosphorus (P) while primarily focusing on ammonium (NH4+) recovery were undergone for a detailed investigation. Frequent backwashing, involving intermittent water and air injection, was used to mitigate clogging as the main problem of the IE system for treating PTWW. The results revealed a mean removal efficiency of 85 %, 60 %, 50 %, and 30 % for NH4+, TSS, TCOD, and total phosphorus (TP), respectively, per cycle exclusively for the IE system. As the system scaled up, a substantial reduction was observed in the adsorption capacity, shifting from approximately 12 to 1 g NH4+ (kgCIO)-1. Despite this drawback, the study's finding showed that prolonged treatment of PTWW for NH4+ removal and recovery in municipal WWTPs, besides substantially reducing carbonaceous pollutants, is applicable. Implementing this application will not only decrease the biological treatment costs for municipal wastewater but also yield valuable by-products, such as NH4Cl, which can serve as a foundational material for the production of ammonium chloride fertilizer. Therefore, transitioning to IE systems in municipal WWTPs will diminish the reliance on resource-intensive methods like the Harber-Bosch procedure for producing nitrogen fertilizer.

Valorization of organic carbon in primary sludge via semi-continuous dark fermentation: First step to establish a wastewater biorefinery.

In this study, lab-scale, bench-scale, and pilot-scale experiments were carried out to optimize short-chain fatty acids production from primary sludge. Batch tests showed the requirement of short retention times and semi-continuous operation mode showed a plateau of maximum daily productivity at 36-hours hydraulic retention time with minimal methanation. Optimization from pH 5 to pH 10 at 36 h-hydraulic retention time under long-term semi-continuous operating mode revealed that production of short-chain fatty acids was pH dependent and highest yields could be achieved at pH 7 by establishing optimum redox conditions for fermentation. Pilot-scale experiments at 32 °C showed that daily productivity (3.1 g∙Lreactor-1∙dHRT-1) and yields (150 mg∙gVS-1; OLR = 21 gVS∙Lreactor-1∙dHRT-1; pH 7) of short-chain fatty acids could be significantly improved, specifically for acetic and propionic acids. From these results, a robust dark fermentation step for recovery of valuable products from the solids treatment step in a biorefinery can be achieved.

Material attrition and bone micromorphology after conventional and ultrasonic implant site preparation.

OBJECTIVES: Little is known about the recently introduced ultrasonic implant site preparation. The purpose of this study was to compare material attrition and micromorphological changes after ultrasonic and conventional implant site preparations. MATERIAL AND METHODS: Implant site preparations were performed on fresh bovine ribs using one conventional (Straumann, Freiburg, Germany) and two ultrasonic (Piezosurgery; Mectron Medical Technology, Carasco, Italy and Variosurg; NSK, Tochigi, Japan) systems with sufficient saline irrigation. Sections were examined by environmental scanning electron microscopy (ESEM). Energy-dispersive X-ray spectroscopy (EDX) was performed to evaluate the metal attrition within the bone and the irrigation fluid. RESULTS ESEM: After conventional osteotomy, partially destroyed trabecular structures of the cancellous bone that were loaded with debris were observed, whereas after ultrasonic implant site preparations, the anatomic structures were preserved. EDX: None of the implant site preparation methods resulted in metal deposits in the adjacent bone structures. However, within the irrigation liquid, there was significantly higher metal attrition with ultrasonic osteotomy (P < 0.0001 and P < 0.0001 for Mectron and NSK, respectively). Whereas for Straumann system used, 15.5% of the SEM/EDX findings were drill-origin metals, this percentage increased to 37.3% and 37.9% with the application of Mectron and NSK, respectively. CONCLUSIONS: Ultrasonic implant site preparation is associated with the preservation of bone microarchitecture and with the increased attrition of metal particles. Therefore, copious irrigation seems to be even more essential for ultrasonic implant site preparation than for the conventional method.

The transmaxillary endoscopic approach to the orbit.

OBJECTIVE: In this surgical-anatomical cadaveric study we investigate the feasibility of the transmaxillary endoscopic approach to the intraorbital space. Anatomical landmarks are defined, the endoscopic view in the orbital space is studied and complications that can occur are discussed. METHODS: Nine formalin-fixed heads were used to study the transmaxillary endoscopic approach to the orbit. The approach was used twice on each head (once for each maxilla). Therefore, we report our results on 18 transmaxillary intraorbital approaches. For better differentiation of anatomical structures, the veins and arteries were injected with blue and red plastic respectively in six cadaveric heads. RESULTS: The transmaxillary approach enables viewing the inferior intraconal structures without endangering the infraorbital nerve and its artery and without diversion of the inferior rectus muscle. The optic nerve was visualised more easily through the approach medial to the inferior rectus muscle instead of lateral to the muscle since the ciliary nerves are in the way in the lateral approach. The combination of the approaches medial and lateral to the inferior rectus muscle allows very good identification of all important anatomical structures in the inferior intraconal space. CONCLUSION: The transmaxillary endoscopic approach to the orbit is a useful new approach in the surgical armamentarium for orbital lesions. The overview of the inferior part of the orbit is excellent, and the lateral part of the optic nerve can be visualised. Careful anatomical dissection allows visualisation of important anatomical structures in the orbit without damaging nerves or arteries.

Perceptions of media influence and performance among politicians in European democracies.

This study explores politicians' subjective views of the mediatisation of politics and the implication it has for their satisfaction with democracy. Based on previous research, we hypothesise a negative effect of their perception of media influence on their evaluation of the news media's performance as a public informant. These perceptions directly and indirectly influence politicians' satisfaction with democracy. The relationships were tested with a Structural Equation Model (SEM) based on comparative survey data from politicians in seven democracies (Austria, Denmark, France, Germany, Spain, Sweden, Switzerland). Results show that a strong influence runs from politicians' perception of the media's performance as regards public information to their satisfaction with the functioning of democracy. This influence is stable across countries. The SEM thus may provide a good explanation for why some politicians attack legacy media and excessively use social media to communicate with voters. Results also point to risks of media-driven democracies.

Micromorphometrical analyses of five different ultrasonic osteotomy devices at the rabbit skull.

OBJECTIVES: The recently introduced ultrasonic osteotome procedure is an alternative to conventional methods of osteotomy. The aim of the present study was to establish the differences between five recently introduced ultrasonic osteotomes and to perform micromorphological and quantitative roughness analyses of osteotomized bone surfaces. MATERIALS AND METHODS: Fresh, standard-sized bony samples were taken from a rabbit skull using the following ultrasonic osteotomes: the Piezosurgery 3 with insert tip OT7, Piezosurgery Medical with insert tip MT1-10, Piezon Master Surgery with insert tip SL1, VarioSurg with inert tip SG1, and Piezotome 2 with insert tip BS1 II. The required duration of time for each osteotomy was recorded. The prepared surfaces were examined via light microscopy, environmental surface electron microscopy (ESEM), and confocal laser scanning microscopy (CLSM). RESULTS: All of the investigated piezoelectric osteotomes preserved the anatomical structure of bone. The mean roughness values of the osteotomized bone edge obtained using the investigated piezoelectric osteotomes were as follows: 2.47 µm (Piezosurgery 3), 9.79 µm (Piezosurgery Medical), 4.66 µm (Piezon Master Surgery), 6.38 µm (VarioSurg), and 6.06 µm (Piezotome 2). Significantly higher roughness values were observed when using the Piezosurgery Medical in comparison with those achieved by the Piezosurgery 3 (P<0.0001) and Piezon Master Surgery (P=0.002). Different osteotomy durations were achieved using the different piezoelectric osteotomes: 144 s (Piezosurgery 3), 126 s (Piezosurgery Medical), 142 s (Piezon Master Surgery), 149 s (VarioSurg), and 137 s (Piezotome 2). CONCLUSIONS: In the present study, micromorphological differences following the use of various ultrasonic devices were clearly identified. According to this study, it can be concluded that the power and the composition of the teeth of the insert tip might impact procedure duration and cutting qualities.

Alveolar bone stress around implants with different abutment angulation: an FE-analysis of anterior maxilla.

OBJECTIVES: To comparatively assess the masticatory stress distribution in bone around implants placed in the anterior maxilla with three different labial inclinations. MATERIALS AND METHODS: Three-dimensional finite element models were fabricated for three situations in anterior maxilla: (1) a fixture in contact with buccal cortical plate restored by straight abutment, (2) a fixture inclined at 15 degrees, and (3) 20 degrees labially restored with corresponding angled abutment. A palatal bite force of 146 N was applied to a point 3 mm below the incisal edge. Stress distribution around the bone-fixture interface was determined using ANSYS software. RESULTS: The maximum compressive stress, concentrated in the labial crestal cortical bone, was measured to be 62, 108, and 122 MPa for 0-, 15-, and 20-degree labially inclined fixtures, respectively. The maximum tensile stress, concentrated in the palatal crestal cortical bone, was measured to be 60, 108, and 120 MPa for 0-, 15-, and 20-degree labially inclined fixtures, respectively. CONCLUSIONS: While all compressive stress values were under the cortical yield strength of 169 MPa, tensile stress values partially surpassed the yield strength (104 MPa) especially when a 20-degree inclination was followed for fixture placement.

Acrylic resin polymerization in direct contact to the abutment and the temperature at bone-implant interface: a pilot in vitro study.

Three autopolymerizing acrylic resins were applied to a titanium alloy abutment connected to 2 different diameters of an implant. The implants were embedded in fresh iliac bone of sheep in a 37°C water bath. Temperature changes were recorded via embedded thermocouples at the cervical (T1) and apical (T2) regions of the implant surface. Polymerization temperature of acrylic resins did not seem to exceed the critical threshold of 47°C.

Heat production during different ultrasonic and conventional osteotomy preparations for dental implants.

OBJECTIVES: The purpose of this study was to evaluate the intraosseous temperature changes during ultrasonic and conventional implant site preparation in vitro with respect to the effect of load and irrigation volume. MATERIAL AND METHODS: Implant sites were prepared using two different ultrasonic devices (Piezosurgery, Mectron Medical Technology and VarioSurg, NSK) and one conventional device (Straumann) at loads of 5, 8, 15 and 20 N and with irrigation volumes of 20, 50 and 80 ml/min. During implant site preparation, temperatures were measured in fresh, equally tempered bovine ribs using two thermocouples placed at a distance of 1.5 mm around the drilling site in cortical and cancellous bone. The preparation time was recorded. RESULTS: The heat production and time required for implant site preparation using both ultrasonic devices were significantly higher than those for conventional drilling (P<0.01). Increased loading had no effect on heat production. A higher irrigation volume was associated with a diminished temperature increase in the cortical bone for ultrasonic but not for conventional drilling, which resulted in significantly lower temperatures in cortical as compared with cancellous bone during ultrasonic implant site preparation. CONCLUSIONS: Ultrasonic implant site preparation is more time consuming and generates higher bone temperatures than conventional drilling. However, with the levels of irrigation, ultrasonic implant site preparation can be an equally safe method.

Trigeminocardiac reflex, bilateral sagittal split ramus osteotomy, Gow-Gates block: a randomized controlled clinical trial.

PURPOSE: The behavior of trigeminocardiac reflex (TCR) during maxillofacial surgeries has not yet been sufficiently studied and knowledge of its behavior is limited to some case reports. The present study aimed to assess the occurrence of TCR in bilateral sagittal split ramus osteotomy and to determine the possible effect of Gow-Gates block on its incidence. MATERIALS AND METHODS: Twenty candidates for bilateral sagittal split ramus osteotomy (included were American Society of Anesthesiologists I Class III patients with a prognathism of 3 to 5 mm) were given routine general anesthesia after at least 12 hours of fasting. All patients received Gow-Gates mandibular nerve block on 1 random side (case ramus; the other side was used as the control) after induction of general anesthesia before surgery. Pulse rate was recorded at baseline, soft tissue cutting, bone cutting, sagittal splitting, setback manipulation, and recovery. Mean pulse rate values were compared statistically using t test for the 2 sides in patients. RESULTS: No statistically significant differences were found between the blocked and control sides except during ramus sagittal splitting and setback manipulation (P < .0001), when a significantly decreased pulse rate was recorded for the control ramus compared with the blocked ramus. CONCLUSIONS: The present study provides further evidence for the complex neurophysiologic mechanism and probable prevention of peripheral TCR. The results of the present study should be further validated through future studies but already provide strong evidence that peripheral and central TCR may act differently based on slightly different pathways.

Buccal periosteal inversion (BUPI) for defect closure and keratinized gingiva width preservation after tooth extraction - technique modification.

INTRODUCTION: Several techniques and methods have been proposed to cover alveolar bone after tooth extraction when soft tissue is lacking. Some authors recommend soft tissue flap techniques, and others advocate different types of materials for socket covering. In this article, the authors use a modified buccal inversion technique for adequate coverage of the alveolar ridge to ensure its preservation and to minimize soft tissue shrinkage and loss of keratinized gingiva after tooth extraction. This local mucogingival-periosteal plastic procedure was named by the authors the "Buccal Periosteal Inversion technique" or simply BUPI. MATERIALS AND METHODS: After extraction of a fractured, endodontically compromised lower right first molar, the BUPI technique was performed to cover the alveolus. After reflecting the two-sided full-thickness flap, the periosteum was split in the cranial direction. The inverted periosteum is used to provide tension-free defect closure of the postextractional defect. Detailed technique implementation and patient postoperative healing are presented here in detail. RESULTS: Postoperative evaluation at six weeks was presented with photos showing adequate surgical site healing, no signs of infection or dehiscence, and no crestal shift of the keratinized gingiva. CONCLUSION: The buccal periosteal inversion (BUPI) technique is a modified technique that allows full socket coverage, avoiding a keratinized gingiva shift in the crestal direction using only the periosteum as a cover material. By inverting the buccal ridge periosteum alone from its normal position, the osteoclastic effect on the buccal bony wall will be eliminated, and this procedure abolishes the need for additional alveolar coverage materials.

Particulated wisdom teeth as an autologous bone substitute for grafting/filling material in bone defects: Case Report.

INTRODUCTION: Bone augmentation material using permanent teeth are confirmed in many articles to provide good histological and clinical results. Advances in osteoconduction and osteoinduction, low cost of material, no risk of disease transmission and elimination of foreign body reaction are important aspects not only to the clinician but to patient as well. Many techniques and devices to obtain graft material for bone augmentation out of teeth are found in the literature. MATERIAL AND METHODS: The wisdom teeth crush technique developed in our office and described in this case report is simple and no specific devices for teeth grinding were used. The graft material was obtained from impacted intact wisdom teeth without chemical conditioning of the particles with preservation of the dental pulp and the cells found in it. This study presents crushed autologous maxillary wisdom tooth as filling material in two bone defects in premaxilla caused by cysts removal. RESULTS: The clinical results and Panoramic X-ray evaluation at three months postoperatively were very promising. CONCLUSIONS: Although further clinical researches are necessary to evaluate this substitutive for bone augmentation technique, the authors believe it can be safely used by oral/maxillofacial surgeons. Key words:Particulated wisdom tooth, autologous augmentation, bone substitutes, wisdom teeth crush technique.

Adhesion Behaviour of Primary Human Osteoblasts and Fibroblasts on Polyether Ether Ketone Compared with Titanium under In Vitro Lipopolysaccharide Incubation.

The aim of this in vitro pilot study was to analyse the adhesion behaviour of human osteoblasts and fibroblasts on polyether ether ketone (PEEK) when compared with titanium surfaces in an inflammatory environment under lipopolysaccharide (LPS) incubation. Scanning electron microscopy (SEM) images of primary human osteoblasts/fibroblasts on titanium/PEEK samples were created. The gene expression of the LPS-binding protein (LBP) and the LPS receptor (toll-like receptor 4; TLR4) was measured by real-time polymerase chain reaction (PCR). Immunocytochemistry was used to obtain evidence for the distribution of LBP/TLR4 at the protein level of the extra-cellular-matrix-binding protein vinculin and the actin cytoskeleton. SEM images revealed that the osteoblasts and fibroblasts on the PEEK surfaces had adhesion characteristics comparable to those of titanium. The osteoblasts contracted under LPS incubation and a significantly increased LBP gene expression were detected. This was discernible at the protein level on all the materials. Whereas no increase of TLR4 was detected with regard to mRNA concentrations, a considerable increase in the antibody reaction was detected on all the materials. As is the case with titanium, the colonisation of human osteoblasts and fibroblasts on PEEK samples is possible under pro-inflammatory environmental conditions and the cellular inflammation behaviour towards PEEK is lower than that of titanium.

Bright sub-20-nm cathodoluminescent nanoprobes for electron microscopy.

Electron microscopy has been instrumental in our understanding of complex biological systems. Although electron microscopy reveals cellular morphology with nanoscale resolution, it does not provide information on the location of different types of proteins. An electron-microscopy-based bioimaging technology capable of localizing individual proteins and resolving protein-protein interactions with respect to cellular ultrastructure would provide important insights into the molecular biology of a cell. Here, we synthesize small lanthanide-doped nanoparticles and measure the absolute photon emission rate of individual nanoparticles resulting from a given electron excitation flux (cathodoluminescence). Our results suggest that the optimization of nanoparticle composition, synthesis protocols and electron imaging conditions can lead to sub-20-nm nanolabels that would enable high signal-to-noise localization of individual biomolecules within a cellular context. In ensemble measurements, these labels exhibit narrow spectra of nine distinct colours, so the imaging of biomolecules in a multicolour electron microscopy modality may be possible.