Pyrophyllite, with the chemical formula Al2Si4O10(OH)2, is a naturally occurring and abundant van der Waals mineral belonging to the group of phyllosilicates. It is very soft, layered crystal used ...for sculpting and an excellent electrical and thermal insulator aimed for the operation at high pressure and temperature. Here, for the first time, two-dimensional (2D) pyrophyllite obtained by both mechanical and liquid phase exfoliation is presented and investigated at the nanoscale. The layered structure provides low friction coefficient of around 0.1 as measured by friction force microscopy. The wear properties, studied by atomic force microscope (AFM) based scratching, are distinctly different from graphene. Since the wear is initiated at low normal forces, 2D pyrophyllite can be routinely carved by the AFM tip and it is suitable for scratching based nanolithography. According to our optical measurements, 2D pyrophillite is an insulator with a band gap of ∼5.2eV. Local current measurements by conductive AFM reveal that 2D pyrophyllite flakes behave as efficient electrical insulators with a breakdown voltage of around 6MV/cm. Therefore, the obtained results indicate possible applications of 2D pyrophyllite as a low-cost electric insulator and lubricant, as well as an easily-machinable material at the nanoscale.
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•First-time mechanical and liquid phase exfoliation of 2D pyrophyllite.•2D pyrophyllite provides low friction coefficient of around 0.1.•Routinely carved and suitable for scratching based nanolithography.•An insulator with a band gap of 5.2 eV and breakdown voltage of 6 MV/cm.•Low-cost electric insulator, lubricant and easily-machinable at the nanoscale.
Gentamicin, belonging to the aminoglycosides, possesses the greatest nephrotoxic effect of all other antibiotics from this group. On the other hand, pioglitazone, which represents peroxisome ...proliferator-activated receptor γ (PPARγ) agonist recently showed antiinflamatory, antioxidative effects, amelioration of endothelial dysfunction etc. Therefore, the goal of our study was to investigate the effects of pioglitazone on kidney injury in an experimental model of gentamicin-induced nephrotoxicity in rats. These effects were observed by following values of biochemical (serum urea and creatinine) parametars, total histological kidney score, urine level of kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) as well as parametars of oxidative stress (malondialdehyde, superoxide dismutase, catalase, total oxidant status, total antioxidant status, oxidative stress index and advanced oxidation protein products). It seems that pioglitazone protects the injured rat kidney in a U-shaped manner. Medium dose of pioglitazone (1 mg/kg, i.p.) was protective regarding biochemical (serum urea and creatinine), total histological score and the values of kidney injury molecule-1 (KIM-1) (P < 0.05 vs. control group, i.e. rats injected with gentamicin only). This finding could be of great importance for the wider use of aminoglycosides, with therapy that would reduce the occurrence of serious adverse effects, such as nephrotoxicity and acute renal failure.
Dispepsija je poremećaj koji obilježavaju dispeptički simptomi lokalizirani u žličici i vezani uz razgradnju hrane u početnom
dijelu probavnoga sustava. Kod funkcijske dispepsije, za razliku od ...organske dispepsije, ne postoji podležeća organska
bolest koja bi prouzrokovala dispeptičke simptome. Imune i promjene funkcije sluznice te motiliteta želuca, drukčiji sastav
mikrobiote i obrada signala u središnjem živčanom sustavu smatraju se odgovornim za nastanak poremećaja. Dijagnoza se
postavlja na temelju anamneze, kliničke slike i isključenjem drugih organskih bolesti probavnoga sustava koje se očituju
dispeptičkim simptomima. Terapija uključuje eradikaciju infekcije bakterijom Helicobacter pylori, inhibitore protonske pumpe,
prokinetike, neuromodulatore, biljne pripravke. Nažalost, kod dijela bolesnika navedena terapija dovodi do slabog ili nikakavog
poboljšanja. Učestalost funkcijske dispepsije sve više raste. Postala je jedna od češćih gastroenteroloških dijagnoza.
Kako bi se smanjili troškovi vezani uz dijagnostiku i liječenje poremećaja potrebno je do kraja rasvijetliti mehanizme te tako
omogućiti pronalazak odgovarajuće terapije za sve podskupine bolesnika.
Even though Industry 4.0 is primarily focused on the implementation of advanced digital technologies, this is not the only aspect that should be considered. One of the aspects that calls for ...attention is the ability to create a sustainable and agile industrial environment. In this sense, the role of project management is crucial for achieving business excellence in a new industrial paradigm. The main goal of this paper was to determine the impact of different levels of project management maturity on business excellence in the context of Industry 4.0. The research in the paper was made using a sample of 124 organizations, differing in industry type and size, and recognized through the business excellence awards or recognitions given by European Foundation for Quality Management (EFQM). Using the Project Management Maturity Model (ProMMM), a significant connection was found between project management maturity and business excellence. Considering technology advances, these relationships were further examined in the context of Industry 4.0. Empirically based conclusions were drawn, which contribute to the literature on project management and business excellence in the context of Industry 4.0. Practitioners can implement them for more effective project management with the intention of bringing excellence into the organization’s operations and results. Additionally, they can be useful to help organizations better cope with changing technology trends.
An efficient method for generating samples of two uniformly distributed random variables (RVs) on the interval (- 1,1) with prescribed correlation coefficients is proposed in this article. The need ...for research arises during the application of the Monte Carlo method (MCM) in determining uncertainty when the input quantities are correlated. The results of the experiment in determining the voltage ratio of a resistive divider are presented. Uncertainty was determined using the guide to the expression of uncertainty in measurement (GUM). The results were confirmed by MCM using the proposed FOLD method.
Pertussis continues to be a significant public health concern. We aimed to examine the epidemiological characteristics of pertussis in Vojvodina, which accounts for almost a third of Serbia's ...population. Our aim was to determine the overall and age-specific incidence and mortality rates of pertussis in Vojvodina from 1948 to 2023, as well as the coverage of immunization against pertussis from 1960 to 2023. In the period 1948-2023, 42,259 cases of pertussis were reported. Following the introduction of the DTwP vaccine (1960) in Serbia, the reported incidence of pertussis began to decline. In 2001, for the first time since introduction of pertussis surveillance in Vojvodina, no pertussis cases were reported. Since 2012, the reported incidence of pertussis has once again increased, and peaked (41.1/100,000) in 2023, approaching the incidence rates recorded shortly after the introduction of DTwP vaccine. A shift in the age profile of pertussis from children aged 0-6 years to school-aged children (7-14 years) occurred between 2012 and 2023, when 48.3% of pertussis cases occurred in this age group. Although the incidence rates of pertussis among individuals aged 20 years and older were significantly lower than among younger age groups, there is evidence of an increasing trend in pertussis cases, particularly among those aged 40-49 years, since 2012. Based on the findings of this study, it is imperative to introduce additional booster doses of the aP vaccine for individuals aged 14 years, along with implementing maternal immunization strategies targeting women of childbearing age.
Pituitary xanthogranulomatomas (XG) are a rare pathological entity caused by accumulation of lipid laden macrophages and reactive granuloma formation usually triggered by cystic fluid leakage or ...hemorrhage. Our aim was to compare clinical characteristics and presenting features of patients with secondary etiology of XG and those with no identifiable founding lesion (primary -“pure” XG) in order to gain new insights into this rare pituitary pathology. In a retrospective review of 714 patients operated for sellar masses, at tertiary center, we identified 16 (2.24%) with histologically confirmed diagnosis of pituitary XG over the period of 7 years (2015–2021). Patients were further analyzed according to XG etiology: “pure”- XG (n = 8) with no identifiable founding lesion were compared to those with histological elements of pituitary tumor or cyst – secondary XG (n = 8). We identified 16 patients (11 male), mean age 44.8 ± 22.3 years, diagnosed with pituitary XG. Secondary forms were associated with Ratke’s cleft cyst (RCC, n = 2) and pituitary adenoma (PA, n = 6). The most common presenting features in both groups were hypopituitarism (75%), headache (68.5%) and visual disturbances (37.5%). Predominance of male sex was noted (males 68.75%, females 31.25%), especially in patients with primary forms. Patients with primary pituitary XG were all males (p = 0.0256) and more frequently affected by panhypopituitarism (87.5% vs. 25%, p = 0.0406) compared to patients with secondary causes. Hyperprolactinemia was noted in pituitary tumor group with secondary etiology only (p = 0.0769). Majority of lesions were solid on magnetic resonance imaging - MRI (81.25%). Distinct clinical phenotype was observed dependent on the etiology of XG.
Ischemic reperfusion kidney injury (IRKI) is a complex pathophysiological event, which is the most common cause of the acute kidney injury. The key characteristic of IRKI is a reduction in glomerular ...filtration rate, which implies an underlying impairment in hemodynamic regulation. In recent decades, convincing evidence illuminated the molecular and pathological events in the acute kidney injury, revealing the role of ischemia/reperfusion, oxidative stress, apoptosis, inflammation, fibrosis and changes in gene expression which activate different signaling pathways. The cascade of inflammation events is a key mediator of IRKI, which includes the inflammation process, complement activation and mobilization of innate immunity. Oxidative stress represents the increased presence of various free radicals that cannot be buffered by the antioxidant capacity which comprises of enzymatic and non-enzymatic components. Renal tissue injury during ischemia/reperfusion comes as a result of membrane lipids peroxidation, oxidative damage of proteins and DNA and results in apoptosis and necrosis. It is evident from many studies that augmentation of the antioxidant defense mechanisms has a protective role on kidney tissue. In recent years, the importance of heat-shock proteins and MicroRNAs in the pathogenesis of IRKI has been revealed and there are promising indications that in future they could serve as diagnostic biomarkers or therapeutic targets. Striking changes in global gene expression were shown, providing a great potential for fundamental understanding and clinical management of IRKI. The clinical outcome among patients with kidney transplantation will have the furthermost advance from the better understanding of the underlying molecular pathology of IRKI.
The aim of this prospective study was to analyze accuracy of sentinel lymph node biopsy with methylene blue dye for intraoperative detection of lateral metastases in clinically N0M0 medullary ...microcarcinomas with calcitonin <1,000 pg/mL and selection of true-positive patients for one-time therapeutic lateral dissection. In addition to total thyroidectomy and central neck dissection, all patients had bilateral sentinel biopsy of jugulo-carotid regions after methylene blue injection to decide upon necessity for lateral dissection. If sentinels were benign on frozen section, additional non-sentinels were extirpated, with no further lateral dissection. If sentinels were malignant, one-time lateral dissection was performed. 20 patients were included in this study. Hereditary disease form was observed in 3/20 (15%) of patients with RET proto-oncogene mutation C634F; remaining 17/20 (85%) were negative for germline mutations. There were no allergic reactions to methylene blue and identification rate of sentinels was 100%. In total, 2/20 (10%) cN0 patients had lymphonodal metastases, thus were reclassified as pN1b. Remaining 18/20 (90%) were classified pN0 based on standard pathohistology. Frozen section findings on sentinels were 100% match with standard pathohistology, and there were no skip metastases in lateral compartments. Sensitivity, specificity and accuracy of sentinel biopsy method with methylene dye and frozen section were 100%. Dzodic’s sentinel lymph node biopsy method can be used for intraoperative assessment of lateral compartments and optimization of initial surgery of medullary microcarcinomas with calcitonin <1,000 pg/mL. This way, cN0 patients with sentinel metastases can receive one-time lateral dissection, and those without benefit from less extensive surgery.
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