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In order to perform the inspection planning process on the coordinate measuring machine (CMM), it is necessary to model the measuring system with workpiece, CMM and fixture. The metrological analysis of the workpiece is then conducted, followed by the creation of a measurement program for simulation on a virtual measuring machine in a CAD environment. This paper presents the modelling and simulation of a virtual measuring system based on a real CMM using PTC Creo Parametric 5.0 software. The simulation involved programming the measuring path and generating a DMIS (*.ncl) file, which represents the standard modelled types of tolerance. The analysis of the metrology of the measuring part for the given forms of tolerance (location, perpendicularity, flatness, etc.) was performed. The components of the CMM and the assembly with defined kinematic connections are also modelled. Following the simulation and generation of the output DMIS file in PTC Creo using the virtual CMM, the real CMM was programmed and used for actual measurements. Subsequently, a measurement report was generated. The main result of this paper is the modelling of an offline Digital Measuring Twin (DMT) based on the DMIS file.

The anthelmintic macrocyclic lactones (MLs) are the most important endectocides in modern pharmacotherapy of parasitic infections. However, during the COVID 19 pandemic, ivermectin was used in humans against infection with the SARS-CoV-2 virus in doses significantly higher than the approved antiparasitic doses. This kind of application was created solely on the basis of in vitro tests, and is not officially approved in any country in the world. Therefore, we conducted a study on rats treated orally with 0.6, 1.2, 2.4 and 4.8 mg/kg of ivermectin for 5 days. Based on our investigation, ivermectin at the doses used in humans against the SARS-Co-2 virus (3, 6, 12 and 24 times higher than the antiparasitic dose 0.2mg/kg), causes changes in red blood cell counts and increases the levels of liver enzymes without visible clinical symptoms. Histopathological changes were recorded in the liver, kidneys and testicles of rats, and the highest dose tested led to bleeding in the brain tissue. Obviously, ivermectin somewhat increases concentration of the enzyme P-450 isoform 3A4, whose substrate it is, but the highest tested dose reduces its concentration in plasma to the control level. Notably, the concentrations of ivermectin recorded in plasma of treated rats, indicate that even high doses do not reach the in vitro IC50 value of ivermectin for SARS-CoV-2 reported in the literature. On the other hand, the concentrations of ivermectin in the brain approach the values that can manifest extremely toxic effects described in humans. Veliki odmerki ivermektina povzročajo toksične učinke pri podganah po kratkotrajnem peroralnem dajanju Izvleček: Protiglivični makrociklični laktoni (ML) so najpomembnejše učinkovine v sodobni farmakoterapiji parazitskih okužb. Vendar so med pandemijo covida-19 pri ljudeh proti okužbi z virusom SARS-CoV-2 uporabljali bistveno višje odmerke ivermektina od odobrenih antiparazitičnih odmerkov. Takšna uporaba je bila ustvarjena izključno na podlagi testov in vitro, vendar ni bila uradno odobrena v nobeni državi na svetu. Zato smo izvedli študijo na podganah, ki smo jih 5 dni peroralno zdravili z 0,6, 1,2, 2,4 in 4,8 mg ivermektina na kg telesne teže. Naša preiskava je pokazala, da ivermektin v povišanih odmerkih, ki se uporabljajo pri ljudeh proti virusu SARS-CoV-2 (3-, 6-, 12- in 24-krat večjih od antiparazitskega odmerka 0,2 mg/kg), povzroča spremembe v številu eritrocitov in zvišuje raven jetrnih encimov brez vidnih kliničnih simptomov. Histopatološke spremembe smo zabeležili v jetrih, ledvicah in testisih podgan, največji testirani odmerek pa je povzročil krvavitev v možganskem tkivu. Znano je, da ivermektin kot substrat nekoliko poveča koncentracijo encima P-450 izoforma 3A4, vendar največji testirani odmerek zmanjša njegovo koncentracijo v plazmi na kontrolno raven. Koncentracije ivermektina, zabeležene v plazmi zdravljenih podgan, kažejo, da tudi visoki odmerki ne dosežejo in vitro vrednosti IC50 ivermektina za SARS-CoV2, ki je navedena v literaturi. Po drugi strani pa se koncentracije ivermektina v možganih približujejo vrednostim, ki lahko povzročijo izjemno toksične učinke, opisane pri ljudeh. Ključne besede: ivermektin; toksičnost; SARS-CoV-2; citokrom P-450; P-gp; histopatološke spremembe; podgane

Improving the performance, efficiency and productivity of the machining, reducing energy consumption and establishing control over the machining process are the main goals of the production technologies development. This paper provides the basis for establishing of a process management and determining of optimal conditions for performing high-feed milling, as a special machining method. An experimental study of the analysis of the influence of process parameters, namely depth of cut and feed rate, on the output parameters of high-feed milling were carried out. As output indicators of the performance of the high-feed milling, namely the energy efficiency of the machine tool and the productivity of the machining process were analysed. Based on experimental data, analysis and modelling of the material removal rate per unit of time and electrical energy consumption were carried out. A workpiece made from aluminium was machined on a three-axis machining centre. By using the boundaries of the domain of process parameters and the optimization objective function, the optimization of the values of the process parameters was carried out. As an optimal solution, the following process parameters were obtained: cutting depth ap = 2 mm and feed rate vf = 1500 mm/min.

Abstract GCaMP is a genetically encoded calcium indicator (GECI) widely used in neuroscience research. It measures intracellular Ca2+ level by fluorescence changes as it directly binds to Ca2+. In this process, the effect of this calcium buffer on the intracellular calcium signaling and cell physiology is often not taken into consideration. However, growing evidence from calcium imaging studies shows GCaMP expression under certain conditions can generate aberrant activity, such as seizures. In this study, we examined the effect of GCaMP6 expression in the dentate gyrus (DG) on epileptogenesis. We found that viral expression of GCaMP6s but not GCaMP6f in the DG induces tonic–clonic seizures several weeks after viral injection. Cell-type specific expression of GCaMP6s revealed the granule cells (GCs) as the key player in GCaMP6s-induced epilepsy. Finally, by using slice electrophysiology, we demonstrated that GCaMP6s expression increases neuronal excitability in the GCs. Together, this study highlights the ability of GCaMP6s in DG-associated epileptogenesis.

Sustainable manufacturing is one of the most important and most challenging issues in present industrial scenario. With the intention of diminish negative effects associated with cutting fluids, the machining industries are continuously developing technologies and systems for cooling/lubricating of the cutting zone while maintaining machining efficiency. In the present study, three regression based machine learning techniques, namely, polynomial regression (PR), support vector regression (SVR) and Gaussian process regression (GPR) were developed to predict machining force, cutting power and cutting pressure in the turning of AISI 1045. In the development of predictive models, machining parameters of cutting speed, depth of cut and feed rate were considered as control factors. Since cooling/lubricating techniques significantly affects the machining performance, prediction model development of quality characteristics was performed under minimum quantity lubrication (MQL) and high-pressure coolant (HPC) cutting conditions. The prediction accuracy of developed models was evaluated by statistical error analyzing methods. Results of regressions based machine learning techniques were also compared with probably one of the most frequently used machine learning method, namely artificial neural networks (ANN). Finally, a metaheuristic approach based on a neural network algorithm was utilized to perform an efficient multi-objective optimization of process parameters for both cutting environment.

Biofilm removal from the apical region of the periodontal or peri-implant pocket, which is very difficult to achieve with mechanical instruments, is a major unresolved issue in dentistry. Here, we propose the use of photoacoustically induced streaming and secondary cavitation to achieve superior cleaning efficacy in the apical region of the periodontal and peri-implant pocket. We have used a prefabricated narrow wedge system that mimics the consistency of periodontal and peri-implant pockets of both healthy and severely inflamed tissue. We studied the effect of single-pulse modality Er:YAG on Pseudomonas aeruginosa biofilm removal. We used different laser energies, fiber-tip positions, and laser treatment durations. The cleaning process was monitored in real-time with a high-speed camera after each individual laser pulse application. The obtained results suggest that biofilm cleaning efficacy in a difficult-to-reach place in healthy model tissue is directly related to the onset of secondary cavitation bubble formation, which correlates with a significant improvement of biofilm removal from the apical region of the periodontal or peri-implant pocket. In comparison to the healthy tissue model, the laser energy in inflamed tissue model had to be increased to obtain comparable biofilm cleaning efficacy. The advantage of photoacoustic cavitation compared to other methods is that laser-induced cavitation can trigger secondary cavitation at large distances from the point of laser application, which in principle allows biofilm removal at distant locations not reachable with a laser fiber tip or other mechanical instruments.

This paper explores collaborative literary analysis between a human and AI assistant. Prompting the conversational agent Claude iteratively, the author directs an examination of Abbott’s Flatland structured around psychoanalytic critique and connections to scientific paradigm shifts. Each draft refines the analysis by incorporating academic conventions like citations and expanding discussion of social hierarchies. The iterative process elicits the AI’s unique interpretations while nudging it toward increased scholarly rigor. While noting Claude’s limitations in accuracy, the reflective commentary finds AI can productively expand human scholarship if treated as a partner, not just a tool. Additional ethical implications of advancing AI emergence in academia are considered, such as establishing frameworks for responsible and equitable integration. Overall, the collaborative project suggests measured, humane guidance elicits meaningful scholarly contributions from AI without compromising rigor. But care must be taken to avoid overlooking long-term pitfalls in our rush to capitalize on AI productivity gains. Author's note: This abstract and the title are by the AI, Claude 2

Copyright of FME Transactions is the property of University of Belgrade, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sustainable production requires reducing of production waste, energy consumption, and more efficient machining processes. However, in machining must be introduced advanced techniques for cooling and lubrication of cutting zone. An advanced techniques is minimum quantity lubrication (MQL), can be considered as a step towards sustainable machining. However, it is important to analyze cutting processes regard to energy consumption indicators, especially when machining materials that have a wide range of applications, such AISI 1045. In this study, the influence of process parameters on turning energy performance during turning of mentioned steel under MQL lubrication conditions were investigated. Full experiment plan was used, ANOVA was used for effect analyze, and RSM was used for modelling. Multi-objective optimization of process parameters, based on minimizing energy indicators, was performed. Procedure was defined cutting speed of 210 m/min, depth of cut of 1.5 mm, and feed rate of 0.224 mm/rev as optimal parameters. These parameters and MQL conditions can be used to get minimum energy indicators in AISI 1045 turning, especially in large-scale production.

Copyright of FME Transactions is the property of University of Belgrade, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, Teng et al. identify a population of glutamatergic neurons in the ventrolateral medulla that control Non-Rapid Eye Movement (NREM) sleep in mice. They uncover an excitatory brainstem-hypothalamic circuit that controls wake-sleep transitions.

Sleep is a conserved biological process in the animal kingdom. Understanding the neural mechanisms underlying sleep state transitions is a fundamental goal of neurobiology, important for the development of new treatments for insomnia and other sleep-related disorders. Yet, brain circuits controlling this process remain poorly understood. A key technique in sleep research is to monitor in vivo neuronal activity in sleep-related brain regions across different sleep states. These sleep-related regions are usually located deeply in the brain. Here, we describe technical details and protocols for in vivo calcium imaging in the brainstem of sleeping mice. In this system, sleep-related neuronal activity in the ventrolateral medulla (VLM) is measured using simultaneous microendoscopic calcium imaging and electroencephalogram (EEG) recording. By aligning calcium and EEG signals, we demonstrate that VLM glutamatergic neurons display increased activity during the transition from wakefulness to non-rapid eye movement (NREM) sleep. The protocol described here can be applied to study neuronal activity in other deep brain regions involved in REM or NREM sleep.

In periodontology and implantology, laser-induced cavitation has not yet been used to treat biofilm-related problems. In this study we have checked how soft tissue affects the evolution of cavitation in a wedge model representing periodontal and peri-implant pocket geometry. One side of the wedge model was composed of PDMS mimicking soft periodontal or peri-implant biological tissue, the other side was composed of glass mimicking hard tooth root or implant surface, which allowed observations of the cavitation dynamics with an ultrafast camera. Different laser pulse modalities, PDMS stiffness, and irrigants were tested for their effect on the evolution of cavitation in the narrow wedge geometry. The PDMS stiffness varied in a range that corresponds to severely inflamed, moderately inflamed, or healthy gingival tissue as determined by a panel of dentists. The results imply that deformation of the soft boundary has a major effect on the Er:YAG laser-induced cavitation. The softer the boundary, the less effective the cavitation. We show that in a stiffer gingival tissues model, photoacoustic energy can be guided and focused at the tip of the wedge model, where it enables generation of secondary cavitation and more effective microstreaming. The secondary cavitation was absent in severely inflamed gingival model tissue, but could be induced with a dual-pulse AutoSWEEPS laser modality. This should in principle increase cleaning efficiency in the narrow geometries such as those found in the periodontal and peri-implant pockets and may lead to more predictable treatment outcomes.

To perform basic research and development to realize future accelerator-driven systems, a lead-bismuth eutectic (LBE) alloy spallation target will be installed within the framework of the Japan Proton Accelerator Research Complex (J-PARC) project, Japan Atomic Energy Agency. The target will be bombarded by high-power pulsed proton beams (250 kW, 400 MeV, 25 Hz, and 0.5 ms in pulse duration). The beam window (BW) of the spallation target is critical because it should survive under severe conditions that occur, i.e., high temperature, high irradiation, intense stress, and various kinds of damage. Therefore, the target vessel should be carefully designed to obtain an adequate safety margin. Our previous research indicates that there is a stagnant flow region in the LBE at the BW tip due to the symmetric configuration of the target, which causes high temperature and concentration of stress on the BW. On the basis of our previous work, three types of upgraded target head designs are studied in the current research to reduce/move the stagnant flow region from the BW tip and to increase the target safety margin. Thermal-hydraulic analyses and structural analyses for the target head designs are carried out numerically under a steady-state condition. Results illustrate that the designs can almost eliminate the stagnant flow region in the LBE. As a consequence, the concentration of thermal stress on the BW is released and greatly decreased. The safety margin of the target is improved through this study. [ABSTRACT FROM AUTHOR]

Summary: Absence seizures, manifested by spike-wave discharges (SWD) in the electroencephalogram, display synchronous reciprocal excitation between the neocortex and thalamus. Recent studies have revealed that inhibitory neurons in the reticular thalamic (RT) nucleus and excitatory thalamocortical (TC) neurons are two subcortical players in generating SWD. However, the signals that drive SWD-related activity remain elusive. Here, we show that SWD predominately occurs during wakefulness in several mouse models of absence epilepsy. In more focused studies of Gnb1 mutant mice, we found that sensory input regulates SWD. Using in vivo recording, we demonstrate that TC cells are activated prior to the onset of SWD and then inhibited during SWD. On the contrary, RT cells are slightly inhibited prior to SWD, but are strongly activated during SWD. Furthermore, chemogenetic activation of TC cells leads to the enhancement of SWD. Together, our results indicate that sensory input can regulate SWD by activating the thalamocortical pathway.

The disinfection and removal of biofilm from titanium dental implants remains a great challenge in oral medicine. Here we present results of novel photoacoustic irrigation laser modalities for biofilm removal in model geometries mimicking the peri-implant pocket. The efficacy of single pulse (Er:YAG-SSP) and dual pulse (Er:YAG-AutoSWEEPS) photoacoustic irrigation modalities were determined for Enterococcus faecalis biofilm decontamination from titanium surfaces in narrow cylindrical and square gap geometries. The density of bacteria as well as the number of live bacteria were determined prior and after different photoacoustic treatments. Both SSP and AutoSWEEPS photoacoustic irrigation techniques removed at least 92% of biofilm bacteria during the 10 s photoacoustic treatment. The effectiveness of cleaning was better in the narrow square gap geometry compared to the cylindrical geometry. The dual pulse Er:YAG-AutoSWEEPS photoacoustic irrigation showed better results compared to SSP modality. No chemical adjuvants were needed to boost the effectiveness of the photoacoustic irrigation in the saline solution. The results imply that photoacoustic irrigation is an efficient cleaning method for debridement and decontamination in narrow geometries and should be considered as a new therapeutic option for the treatment of peri-implant diseases.

This experimental study was conducted to determine the ability of a novel mycotoxins detoxification agent (MR) at a concentration of 0.2% to reduce the toxicity of aflatoxin B1 (AFB1) or T-2 toxin, alone or in combination, and to examine its effect on performance, pathohistological changes (PH) and the residue of these toxins in the tissues of broiler chicks. A total of 96 broiler chicks were divided into eight equal groups: group C, which served as control (without any additives); group MR, which received the novel detoxification agent (supplemented with 0.2%); group E-I (0.1 mg AFB1/kg of diet); group E-II (0.1 mg AFB1/kg of diet + MR 0.2%); group E-III (0.5 mg T-2 toxin/kg of diet); group E-IV (0.5 mg T-2 toxin/kg of diet + 0.2% MR); group E-V (combination of 0.1 mg AFB1/kg, 0.5 mg T-2 toxin/kg of diet); and group E-VI (combination of 0.1 mg AFB1/kg, 0.5 mg T-2 toxin + 0.2% MR). Results indicate that feeds containing AFB1 and T-2 toxin, alone or in combination, adversely affected the health and performance of poultry. However, the addition of MR to diets containing AFB1 and T-2 toxin singly and in combination exerted a positive effect on body weight, feed intake, weight gain, feed efficiency and microscopic lesions in visceral organs. Residual concentration of AFB1 in liver samples was significantly (p < 0.05) decreased when chicks were fed diets supplemented with 0.2% of MR.

The application of remote sensing methods provides useful information that can be used for numerous research. Thus, spatial changes in soil, vegetation, hydrography and such can be analyzed. By analyzing the data obtained by remote sensing methods, high-quality and important data can be obtained for monitoring changes in soil movement caused by landslides. This method provides the possibility of determining the state of the observed space over a longer period of time. Historical aerial imagery has a high level of spatial detail analysis. Comparative analysis of the aerial imagery from the past, recent ones and other surveys can certainly provide information on the trend of ground movement, as well as lead to conclusions for taking specific measures. The present paper gives an example of the analysis of the particular area of the “Umka” landslide based on historical surveys. The “Umka” landslide is located along the right bank of the Sava River near the city of Belgrade, which, with its long-term activity, jeopardizes residential buildings, infrastructure facilities and the population that still lives on it.

Introduction. Peripheral arterial disease (PAD) is a progressive, occlusive and atherosclerotic vascular disease and patients with type 2 diabetes mellitus (DM) are at increased risk of developing this disease. The aim of the study was to determine the frequency of PAD in patients with type 2 DM by measuring the ankle-brachial index (ABI) in the family medicine clinic. Methods. The cross-sectional study included the patients with type 2 DM, registered at the Family Medicine Department of Primary Healthcare Center Laktaši. ABI measurement was carried out by means of the “Boso ABI Mess 100 Oscillometer” apparatus while patients were diagnosed with PAD if the ABI value was 1.3. Results. The study included 178 respondents with type 2 DM, aged ≥50 years, whereby 90 of them (50.6%) were men. PAD was found in 26 (14.6%) respondents. There was a statistically significant difference in ABI (left/ right leg) between the patients with PAD and the ones without it (0.82/0.84 vs. 1.04/1.05; p

Aim: Temporomandibular disorders (TMD) refer to functional disorders of the masticatory system, temporomandibular joint (TMJ) and masticatory muscles. The main objective of this study was to determine whether and to what extent temporomandibular disorders (TMD) affect the maximum bite force (MBF). Methods: The present study included subjects with and without temporomandibular disorder. The presence of TMD was assessed by means of the Helkimo clinical dysfunction index analysis. We measured the maximum bite pressure (MBP) and occlusal contact area (OCA) by means of a Fuji Prescale Pressure measurement film. Based on the MBP and OCA values obtained, MBF values were determined. Results: The MBF values were significantly lower in patients with TMD compared to subjects without TMD (P Conclusion: TMDs have a significant impact on MBF and masticatory muscle action potential. More research is needed to determine the impact of reduced maximum bite force on the functional efficiency of the masticatory system.