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Focused electron beam-induced deposition (FEBID) is a novel technique for the development of multimaterial nanostructures. More importantly, it is applicable to the fabrication of free-standing nanostructures. Experimenting at the nanoscale requires instruments with sufficient resolution and sensitivity to measure various properties of nanostructures. Such measurements (regardless of the nature of the quantities being measured) are particularly problematic in the case of free-standing nanostructures, whose properties must be separated from the measurement system to avoid possible interference. In this paper, we propose novel devices, namely operational micro-electromechanical system (opMEMS) bridges. These are 3D substrates with nanometer-scale actuation capability and equipped with electrical contacts characterised by leakage resistances above 100 GΩ, which provide a platform for comprehensive measurements of properties (i.e., resistance) of free-standing FEBID structures. We also present a use case scenario in which an opMEMS bridge is used to measure the resistance of a free-standing FEBID nanostructure.

Abstract The purpose of this study was to characterize Escherichia coli (E. coli) strains isolated from wild black grouse (Lyrurus tetrix), carried out due to the crossing of hiking trails with wild bird habitats from the Karkonosze National Park. Twenty-seven E. coli isolates were obtained from fecal samples collected during the winter months of 2017 and 2018. The strains were assigned to their relevant phylo-groups and the prevalence of virulence genes characteristic of APEC strains (irp2, astA, iss, iucD, papC, tsh, vat, cva/cvi, stx2f) was checked using PCR analysis. In addition, the phenotypic and genotypic resistance to antibiotics was determined. The entire study provided a better understanding of the potential bacteriological threat to wild birds of the Karkonosze National Park. The results showed that 55.6% of the strains belonged to phylo-group B1 (15/27), 33.3% to group B2 (9/27) and 11.1% to group D (3/27). Among the virulence genes tested, irp2 was detected in 25.9% of isolates (7/27), vat in 22.2% (6/27) and iucD in 3.7% (1/27). The tested E. coli strains showed susceptibility to most antimicrobials, only 14 (51.9%) of them were intermediate resistant or resistant to sulfamethoxazole. The presence of none of the tested genes responsible for resistance to selected antibiotics was identified. Our research indicates a low level of transfer of antimicrobial substances to the natural environment and confirms the effectiveness of the Karkonosze National Park’s activities to protect and restore black grouse habitats.

Introduction and aim: Adenoma pleomorphum (multiform adenoma) is the most popular bening tumor, that originates from the salivary glands. Neoplasm develops mainly from large salivary glands and its occurrence in the nasal cavity is rare and falls mainly in the 3-6 decade of life. Only 1% of all pleomorphic adenomas develop in the nasal and sinus cavities. Despite being a benign tumor, malignant transformation can occur in 2-10% of cases. Description of the case: We report a case of a 21-year-old female ethnically Polish patient with nasal multiform adenoma with initial diagnosis, which indicated a polyp. The final diagnosis was based on the histopathological examination of the resected lesion. The tumor was removed by an endoscopic method with no tissue margins, which may increase the risk of recurrence. Conclusions: Our case demonstrates that despite pleomorphic adenomas typically occurs in the 3rd to 6th decade of life, clinical symptoms are nondistinctive with a polyp and nasal cavity is a very rare location there should be always be increased vigilance leading to choosing best diagnostic measures to form right diagnosis.

One of the most advanced and versatile nanoscale diagnostic tools is atomic force microscopy. By enabling advanced imaging techniques, it allows us to determine various assets of a surface, including morphological, electrical, mechanical, magnetic, and thermal properties. Measuring local current flow is one of the very important methods of evaluation for, for instance, photovoltaic materials or semiconductor structures and other nanodevices. Due to contact areas, the current densities can easily reach above 1 kA/m2; therefore, special detection/measurement setups are required. They meet the required measurement range, sensitivity, noise level, and bandwidth at the measurement scale. Also, they prevent the sample from becoming damaged and prevent unwanted tip–sample issues. In this paper, we present three different nanoscale current measurement solutions, supported with test results, proving their performance.

Abstract Macrodontia is the enlargement of tooth dimensions of different ethologies. This work aims to show a histological evaluation of macrodontic teeth in guinea pigs. The material was obtained from animals postmortem. Ninety structural changes derived from 24 guinea pigs were evaluated. All teeth used in the study showed macrodontic changes. The samples were decalcified, dehydrated and embedded in paraffin. Material was cut in the transverse and longitudinal planes in relation to the alveolar bone. Histological evaluation included apical bud cells, pulp cavity cells, periodontium, dentin, enamel, cementum and alveolar bone tissue. Individual elements were evaluated with respect to their morphology and distribution. Moreover, the arrangement of the individual hard tooth structures was assessed on the teeth. No atypia was found among the cells that make up the apical bud, pulp or periodontal cavity. Displacement of periodontal cells or odontoblasts towards the pulp cavity as well as disorganization of the cell system in the pulp cavity were observed. Changes in the dentine ligaments and the reconstruction of the alveolar bone were also observed in areas where dentine and cement systems were affected. Dental slides were observed and showed that the enamel is also involved in structural remodelling of the pulp cavity. The histological assessment revealed that structural changes in macrodontic teeth involve the rearrangement of typical tooth tissues.

ABSTRACT Lagovirus europaeus (rabbit hemorrhagic disease virus [RHDV]) is a small, nonenveloped, single-stranded RNA virus that causes a severe, highly infectious, and fatal disease in rabbits (Oryctolagus cuniculus) called rabbit hemorrhagic disease (RHD). Since its discovery in the 1980s, it has posed a very serious threat to the global rabbit industry and the rabbit population in the wild. According to data from 2005 to 2018, the occurrence of RHD has been reported or suspected in 50 countries, with more than one-half of the reports being recorded in European countries. The main aim of the study was to detect Lagovirus europaeus (RHDV) strains found in domestic rabbits that died suddenly in the city of Wrocław in southwest Poland. All animals (n = 14) tested in this study died naturally and showed macroscopic features at necropsy that indicated the possibility of death from RHD. As a result of the research, the presence of L. europaeus virus was confirmed in 8 samples of all 14 samples collected. All strains of Lagovirus europaeus isolated in the present study showed 100% nucleotide identity to L. europaeus GI.1 strain FRG and a strain isolated in New Zealand, as well as the L. europaeus GI.1a Erfurt strain. This suggests that it is likely that L. europaeus GI.2 strains have so far not displaced L. europaeus GI.1 strains from the environment in Poland. IMPORTANCE Lagovirus europaeus (RHDV) causes a severe, highly infectious, and fatal disease in rabbits called RHD. The disease is a very serious threat to the global rabbit industry and the rabbit population in the wild. The aim of the study was to detect Lagovirus europaeus (RHDV) strains in domestic rabbits that died suddenly in Poland. The presence of RHDV was confirmed in 8 samples of all 14 samples collected. This is one of the very few reports on the existence of this virus in pet rabbits in Poland.

The measurement method, which utilizes nanomanipulation of the nanowires onto a specially prepared substrate, was presented. It introduced a four-point resistance measurement setup on a chip suited for scanning probe microscopy measurements, integrating connectors and a nanowire specimen. A study on the resistance and resistivity of the thermally post-treated ZnO nanowires at 200 °C and 300 °C in air showed the dependence of these electrical parameters on the annealing temperature. The investigations of the electrical properties of blocks built on the basis of nanowires and their related devices could provide a useful guide not only for designing, fabricating and optimizing electromechanical nanodevices based on nanowires but also for their safe operation in future electronic applications.

In this work, macro- and nanodiagnostic procedures for working, third-generation photovoltaic devices based on a modified polymer:fullerene (P3HT:PCBM) absorber were conducted using atomic force microscopy (AFM) and impedance spectroscopy (IS) equipment. All experiments were performed both in the dark and under irradiation with a specific light wavelength. Photoactive Kelvin probe force microscopy (p-KPFM) and impedance spectroscopy (p-IS) experiments were conducted on half- and whole-solar cell devices. Based on the p-KPFM measurements, the surface potential (SP) and surface photovoltage (SPV) on top of the active layer at the micro/nanoscale were estimated for various light wavelengths (red, green, blue, and white). For light in the red spectrum range, which was associated with an optical absorption edge and acceptor states that occurred in the band gap of the P3HT material after doping the donor polymer with iodine, the SPV was measured at levels of 183 mV, 199 mV, and 187 mV for the samples with 0%, 5% and 10% iodine doping, respectively. In addition, a macroscale investigation enabling the determination of the electrical parameters of the studied organic solar cells (OSCs) was carried out using p-IS. Based on the data obtained during p-IS experiments, it was possible to propose a series electrical equivalent circuit to define and describe the charge transfer phenomenon in the OSCs. Estimations of data obtained from the fitting of the experimental results of p-IS under white light allowed us to evaluate the average diffusion time of electric charges at 8.15 µs, 16.66 µs, and 24.15 µs as a function of organic layer thickness for the device without doping and with 5% and 10% iodine doping. In this study, we demonstrated that correlating information obtained at the macro- and nanoscale enabled a better understanding of the electrical charge distribution of OSCs for indoor applications.

The paper contains the results of the analysis of sodium alginate use as a material for making urethral stents, necessary for the treatment of urinary disorders. Strength tests of the material were carried out, analyzing the characteristics of the material in terms of its interaction with the urethra. The characteristics of the urethra, which is characterized by large deformations, were investigated experimentally. Based on the results of the experiments, geometric dimensions of the stent were developed. According to the results obtained, stent structure was developed, which was implanted into the rabbit urethra. The in vivo study confirmed the assumptions. The implanted stent was effectively and without damage expanded inside the urethra within the assumed diameter variation limits, free flow of urine during the urination was obtained after the implantation, and the proposed design fulfilled the strength assumptions resulting from the pressure of the urethra walls on the stent surface.

The aim of the current study was to to investigate the influence of cornelian cherry (Cornus mas L.; CM) extract on ovariectomy-induced metabolic changes including bone loss, obesity development, adipokines imbalance and oxidative stress. Intragastrical administration of CM ameliorated ovariectomy-induced weight gain and decreased accumulation of visceral fat tissue. It counteracted adipokines imbalance, increasing visfatin and resistin and decreasing adiponectin levels. CM reduced oxidative stress normalizing GPx, and SOD activity, and GSH/GSSG ratio. It ameliorated ovariectomy-induced decrease in femoral and tibial bone mineral density (BMD), prevented the deterioration in Young’s modulus and flexural strength and counteracted ovariectomy-induced decrease in serum calcium level. To our best knowledge this is the first study that demonstrated bone-protective properties of C. mas and its protection against ovarian-cessation obesity, oxidative stress and adipokines imbalance that belong to important risk factors of cardiovascular diseases.

The aim of the study was to investigate in animal model the influence of hops prenylflavonoids on hot flashes and bone loss. Xanthohumol (XN) and hop prenylflavonoids extract (HOP) restored twenty-four-hour variability of tail skin temperature in ovariectomized rats. Additionally XN and HOP increased femoral bone mineral density (BMD) (0.268 ± 0.019 g/cm2 and 0.256 ± 0.013 g/cm2 vs. 0.214 ± 0.015 g/cm2). In micro-computed tomography (mCT) XN and HOP led to a thickening of trabeculae in femurs and vertebral bodies. HOP increased serum osteocalcin (OC) (222.86 ± 39.62 pg/mL vs. 175.87 ± 58.91 pg/mL) and decreased tartrate-resistant acid phosphatase (TRACP) (0.714 ± 0.132 U/L vs. 1.251 ± 0.304 U/L), whereas in XN only decreased TRACP (0.738 ± 0.178 U/L). Results of our study showed that HOP and XN ameliorate ovariectomy induced disturbances in tail skin temperature (TST). Additionally, HOP exerts a mild protective effect on bone loss induced by decline in oestrogen level.

Contact tracing and quarantine are well established non-pharmaceutical epidemic control tools. The paper aims to clarify the impact of these measures in evolution of epidemic. The proposed deterministic model defines a simple rule on the reproduction number [Formula: see text] in terms of ratio of diagnosed cases and, quarantine and transmission parameters. The model is applied to the early stage of Covid19 crisis in Poland. We investigate 3 scenarios corresponding to different ratios of diagnosed cases. Our results show that, depending on the scenario, contact tracing prevented from 50% to over 90% of cases. The effects of quarantine are limited by fraction of undiagnosed cases. The key conclusion is that under realistic assumptions the epidemic can not be controlled without any social distancing measures.

Mangiferin has demonstrated in vitro inhibitory influence on RANKL (Receptor Activator of Nuclear Factor Kappa B Ligand) mediated osteoclasts activity. In this study we evaluated the effect of mangiferin on ovariectomy-induced osteopenia in rats. Animals were randomized into four groups: SHAM (“sham” operated group) and three ovariectomized groups (OVX-C – controls; OVX-M10 – mangiferin 10 mg/kg/day and OVX-M30 – mangiferin 30 mg/kg/day). Mangiferin administration began 3 months after ovariectomy and was continued for 6 consecutive months. In mangiferin-treated rats we demonstrated decrease in bCTX (beta C-terminated telopeptide of type I collagen) level and increase in BMD (bone mineral density) comparing to OVX-C. Bone histomorphometric parameters were in OVX-M10 and OVX-M30 significantly better than in OVX-C. No influence of mangiferin on OC (osteocalcin) level was detected. Thus mangiferin demonstrated antiresorptive influence on bone metabolism and it attenuated ovariectomy-induced bone changes.

Background: Acute myocarditis often progresses to heart failure because there is no effective, etiology-targeted therapy of this disease. Simvastatin has been shown to be cardioprotective by decreasing matrix metalloproteinases’ (MMPs) activity. The study was designed to determine whether simvastatin inhibits MMPs activity, decreases the severity of inflammation and contractile dysfunction of the heart in experimental autoimmune myocarditis (EAM). Methods: Simvastatin (3 or 30 mg/kg/day) was given to experimental rats with EAM by gastric gavage for 21 days. Then transthoracic echocardiography was performed, MMPs activity and troponin I level were determined and tissue samples were assessed under a light and transmission electron microscope. Results: Hearts treated with simvastatin did not show left ventricular enlargement. As a result of EAM, there was an enhanced activation of MMP-9, which was significantly reduced in the high-dose simvastatin group compared to the low-dose group. It was accompanied by prevention of myofilaments degradation and reduction of severity of inflammation. Conclusions: The cardioprotective effects of simvastatin in the acute phase of EAM are, at least in part, due to its ability to decrease MMP-9 activity and subsequent decline in myofilaments degradation and suppression of inflammation. These effects were achieved in doses equivalent to therapeutic doses in humans.

Aim o the study : To compare the potential of CD4+CD25– cells, isolated from both healthy rats and rats with CIA (Collagen-Induced Arthritis), for differentiation into regulatory T cells in the presence of all-trans retinoic acid in order to learn more about the activation mechanisms and therapeutic potential of regulatory T cells. Material and methods : Sorted CD4+CD25– cells were cultured in vitro with/without ATRA, and then the frequency of regulatory T cells and their ability to secrete IL-10 by CD4+ FOXP3+ cells was examined. Gene expression of the foxp3, rarα, rarβ, rxrβ, and ppar β/γ and protein expression of the Rarα, Rarβ, and Rxrβ in cells after stimulation with ATRA were also investigated. Results : CD4+CD25– cells isolated from healthy animals or from animals with CIA are characterised by different potential of the differentiation into CD4+CD25+ FOXP3+ cells. Retinoic acid receptor Rxrβ is present in the CD4+CD25– cells isolated from rats with CIA. Conclusions : We showed that although ATRA did not increase the frequency of Treg in culture, it significantly increased expression of rarα and rxrβ only in lymphocytes taken from diseased animals and foxp3 expression only in healthy animals. Moreover, after ATRA stimulation, the frequency of Treg-produced IL-10 tended to be lower in diseased animals than in the healthy group. The results imply that the potential of naïve cell CD4 lymphocytes to differentiate into Tregs and their putative suppressive function is dependent on the donor’s health status.

Background: Frequency of urethral stenosis makes it necessary to develop new innovative methods of treating this disease. This pathology most often occurs in men and manifests itself in painful urination, reduced urine flow, or total urinary retention. This is a condition that requires immediate medical intervention. Methods: Experimental tests were carried out on a rabbit in order to determine the changes of pressure in the urethra system and to estimate the velocity of urine flow. For this purpose, a measuring system was proposed to measure the pressure of a fluid-filled urethra. A fluoroscope was used to observe the deformability of the bladder and urethra canal. Results: Based on these tests, the range of changes in the urethra tube diameter, the pressures inside the system, and the flow velocity during micturition were determined. Conclusions: The presented studies allowed determining the behavior of the urethra under the conditions of urinary filling. The fluid-filled bladder and urethra increased their dimensions significantly. Such large changes require that the stents used for the treatment of urethral stenosis should not have a fixed diameter but should adapt to changing urethral dimensions.

Bacterial biofilm prevention and eradication are common treatment problems, hence there is a need for advanced and precise experimental methods for its monitoring. Bacterial resistance to antibiotics has resulted in an interest in using a natural bacterial enemy—bacteriophages. In this study, we present the application of quartz tuning forks (QTF) as impedance sensors to determine in real-time the direct changes in Pseudomonas aeruginosa PAO1 biofilm growth dynamics during Pseudomonas phage LUZ 19 treatment at different multiplicities of infection (MOI). The impedance of the electric equivalent circuit (EEC) allowed us to measure the series resistance (Rs) corresponding to the growth-medium resistance (planktonic culture changes) and the conductance (G) corresponding to the level of QTF sensor surface coverage by bacterial cells and the extracellular polymer structure (EPS) matrix. It was shown that phage impacts on sessile cells (G dynamics) was very similar in the 10-day biofilm development regardless of applied MOI (0.1, 1 or 10). The application of phages at an early stage (at the sixth h) and on three-day biofilm caused a significant slowdown in biofilm dynamics, whereas the two-day biofilm turned out to be insensitive to phage infection. We observed an inhibitory effect of phage infection on the planktonic culture (Rs dynamics) regardless of the MOI applied and the time point of infection. Moreover, the Rs parameter made it possible to detect PAO1 population regrowth at the latest time points of incubation. The number of phage-insensitive forms reached the level of untreated culture at around the sixth day of infection. We conclude that the proposed impedance spectroscopy technique can be used to measure the physiological changes in the biofilm matrix composition, as well as the condition of planktonic cultures in order to evaluate the activity of anti-biofilm compounds.

Although mud pumps are vital components of a drilling rig, their failures are frequent. The identification of technical condition of these high-pressure piston pumps is difficult. There are no reliable criteria for the assessment of mud pump condition. In this paper, faults of the pump valve module are identified by means of acoustic emission (AE) signals. The characteristics of these signals are extracted by wavelet packet signal processing. This method has been verified by experiments conducted on a NOV (National Oilwell Varco) -made triplex 14-P-220 mud pump (mounted in the drillship). The results show that the wavelet packet signal processing method can effectively extract the frequency band energy eigenvalues of the signals. Besides, some operational problems associated with high pressure piston mud pumps are presented. A non-invasive method for diagnosing the technical condition of such pumps is being developed at the Maritime University of Szczecin.

The study evaluated the anti-colibacteriosis efficacy of herbs in experimental infection by rabbit pathogenic strain of E. coli O103 eae+. It also studied the effects of herbal mixture added to feed or water on blood parameters. This animal model was used since some E. coli strains pathogenic for rabbits are similar to the strains that are pathogenic to humans. The components of herbal extracts were Rumex crispus, Pontentilla anserine, and Polygonum aviculare. Supplementation was carried out in water (ExpW group) or feed (ExpF group), and four weeks later the animals were infected with the E. coli O103 eae+ strain. The administration of herbs increased the mean concentration of total protein and serum albumin (p < 0.01) without causing disturbances of electrolyte and acid-base balance. The highest total antioxidant capacity (TAS) value (p < 0.01) was observed in the ExpF group. The administration of a mixture of herbs and feed caused more reduction in the number of E. coli in cecum than supplementation into water after an experimental infection. The herbs applied in rabbits did not harm the secretory functions of liver, electrolyte, and acid-base balance of the blood. The application of the tested herbal mixtures can control the activity of the intestinal microbial community.

Miniaturized and integrated analytical devices, including chemical sensors, are at the forefront of modern analytical chemistry. The construction of novel analytical tools takes advantage of contemporary micro- and nanotechnologies, as well as materials science and technology. Two electrochemical techniques were used in experiments: electrochemical impedance spectroscopy and cyclic voltammetry. The goal of this study was to investigate electron transfer resistance in a model solution containing Fe 2 + / 3 + ions and protein adsorption using integrated electrochemical cells with different geometry. Tests performed at various Fe 2 + / 3 + concentration allowed to verify that these cells work properly. The influence of bovine serum albumin adsorbing to the surface of the integrated electrochemical cells was investigated. In electrochemical impedance spectroscopy, the value of R c t increased with protein adsorption and the relative change of R c t was in range 21% to 55%. In cyclic voltammetry the decreasing amperometric response of the working electrode was used as evidence of protein adsorption on the electrode.

Miniaturized and integrated analytical devices, including chemical sensors, are at the forefront of modern analytical chemistry. The construction of novel analytical tools takes advantage of contemporary micro- and nanotechnologies, as well as materials science and technology. The goal of this study was investigate electron transfer resistance in model solution and protein adsorption using integrated electrochemical cell with different geometry.

In this work we present how to describe mechanical impedance of a photon force (PF) MEMS sensor dedicated to structures’ optomechanical studies. An actuating force (photon force) is caused by the reflection and absorption of the electromagnetic radiation beam due to the radiation pressure effect. Specially designed very soft (low k-constant, ca 10–150 mN/m) cantilevers are presented. The structures integrate a Lorentz loop, which enables electromagnetic actuation. The construction with two mirrors is proposed so that parasitic thermal actuation can be neglected. The MEMS displacement is measured with the use of a laser vibrometer. The mechanical impedance model is presented using which the stiffness is calculated. As validation measurements: thermal noise and known mass adding methods are used.