34 research outputs found

    Ideal clocks - a convenient fiction

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    We show that no device built according to the rules of quantum field theory can measure proper time along its path. Highly accelerated quantum clocks experience the Unruh effect, which inevitably influences their time rate. This contradicts the concept of an ideal clock, whose rate should only depend on the instantaneous velocity.Comment: 5 page

    The atypical form of granulomatous lobular mastitis – diagnostic dilemmas: a case report

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    Idiopathic granulomatous mastitis (IGM) is a chronic inflammatory condition that may cause diagnostic difficulties during clinical tests and radiological examinations in terms of differentiation from contagious diseases, such as tuberculosis (TB) and fungal infections, as well as cancer. This report presents the case of a 23-year-old woman with granulomatous mastitis, along with a discussion of the diagnostic dilemmas based on a clinical test, mammography, ultrasonography and histopathological examination. IGM produces varied and non-specific manifestations on mammography and ultra­sonography. Therefore, histopathological examination is necessary to make an unambiguous diagnosis. The possibility of this condition must always be borne in mind to minimise the risk of an erroneous cancer diagnosis. There are no standard procedures in force for the treatment of IGM.Idiopathic granulomatous mastitis (IGM) is a chronic inflammatory condition that may cause diagnostic difficulties during clinical tests and radiological examinations in terms of differentiation from contagious diseases, such as tuberculosis (TB) and fungal infections, as well as cancer. This report presents the case of a 23-year-old woman with granulomatous mastitis, along with a discussion of the diagnostic dilemmas based on a clinical test, mammography, ultrasonography and histopathological examination. IGM produces varied and non-specific manifestations on mammography and ultrasonography. Therefore, histopathological examination is necessary to make an unambiguous diagnosis. The possibility of this condition must always be borne in mind to minimise the risk of an erroneous cancer diagnosis. There are no standard procedures in force for the treatment of IGM

    Effect of relativistic acceleration on localized two-mode Gaussian quantum states

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    We study how an arbitrary Gaussian state of two localized wave packets, prepared in an inertial frame of reference, is described by a pair of uniformly accelerated observers. We explicitly compute the resulting state for arbitrarily chosen proper accelerations of the observers and independently tuned distance between them. To do so, we introduce a generalized Rindler frame of reference and analytically derive the corresponding state transformation as a Gaussian channel. Our approach provides several new insights into the phenomenon of vacuum entanglement such as the highly non-trivial effect of spatial separation between the observers including sudden death of entanglement. We also calculate the fidelity of the two-mode channel for non-vacuum Gaussian states and obtain bounds on classical and quantum capacities of a single-mode channel. Our framework can be directly applied to any continuous variable quantum information protocol in which the effects of acceleration or gravity cannot be neglected.Comment: 21 pages, 13 figures. A few typos correcte

    Shoulder Dislocation Incidence and Risk Factors-Rural vs. Urban Populations of Poland.

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    (1) Background: The aim of this study was to analyze the incidence of shoulder dislocation and to estimate non-modifiable risk factors in rural and urban subgroups in Poland. (2) Methods: The study covered the entire Polish population, divided into urban and rural subgroups and observed between 1 January 2014 and 31 December 2014. The study population consisted of Polish patients with a diagnosis of shoulder dislocation (S43.0) in accordance with the International Statistical Classification of Diseases and Related Health Problems (ICD-10). Records were obtained from the public health care provider National Health Found (Narodowy Fundusz Zdrowia, NFZ). Based on these data, we assessed shoulder dislocation incidence and risk rates, stratifying the study sample by sex, age and place of residence (rural or urban) using the Central Statistical Office (GUS) personal territorial code (TERYT). (3) The incidence was 25.97/100,000 person-years in rural areas and 25.62/100,000 person-years in urban areas. We did not find significant differences in the incidence between the two subgroups. The highest incidence (75.12/100,000 person-years) and the highest risk for shoulder dislocation were found among subjects 80+ years old living in urban areas. Furthermore, men in the third decade of their life living in urban areas showed the highest risk (OR = 7.8, 95% CI; 6.44-9.45, p < 0.001). In both subgroups, the likelihood of shoulder dislocation was significantly lower for the female sex and among children ≤9 years old. However, girls living in rural areas presented with a significantly higher likelihood for dislocation compared with their peers living in urban environments. (4) Conclusions: No significant difference in the incidence rate of shoulder dislocation between Polish residents living in rural and urban areas emerged. The highest incidence was observed among female subjects 80+ years old living in urban environments. The highest risk was found among men in the third decade of their life living in urban areas. In addition, girls in the first decade of their life living in rural areas had more shoulder dislocations than girls living in urban environments. Shoulder dislocation is dominant in female subjects aged 70-79 living in rural areas and in females 80+ years old living in urban areas

    Prevalence of hypoparathyroidism after thyroid surgery depending on diagnosis, the extent of the procedure, and the presence of parathyroid glands in the postoperative examination.

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    Introduction Postoperative hypoparathyroidism can be one of the complications associated with total thyroid removal due to cancer or benign goitre. Purpose The paper aimed to evaluate the prevalence of hypoparathyroidism in patients operated on due to thyroid cancer and nodular goitre, including procedures performed between January 2015 and March 2019 at the Department of Oncological Surgery of the Medical University of Silesia in Katowice. Material and methods The studied group consisted of 595 patients operated on due to cancer and benign nodular goitres. Calcium and phosphate metabolism was assessed using PTH and ionised calcium tests four hours after the surgery. Ionised calcium was checked 30 days after the procedure. Patients who had borderline or below-normal PTH levels in the postoperative period were also subjected to PTH testing after 30 days. In patients with low PTH levels, supplementation with calcium and vitamin D3 was introduced after the surgery. Results Compared to patients operated on for benign goitres, persons diagnosed with cancer were significantly more likely to have PTH levels below 15 pg/ml and serum ionised calcium levels below 4 mg/dl after 30 days following the surgery. The recovery rate was 65.05% vs 82.6% (p < 0.003) and 64.2% vs 84.25% (p < 0.001). The results were similar among patients who underwent lateral and central lymphadenectomy – 33.3% vs 67.3% (p < 0.021) and 25.6% vs 67.6% (p < 0.018). In patients with mild goitres, no significant differences in the recovery rate were observed – 82.6% vs 92.8% (p < 0.327) and 84.25% vs 92.3% (p < 0.437). Patients in whom parathyroid glands were found in the postoperative material were significantly more likely to have decreased PTH and calcium levels after 30 days following the procedure. The recovery rate was 64.1% vs 78.9% (p < 0.027) and 58.06% vs 80.8% (p < 0.004). Conclusions Hypoparathyroidism is not an uncommon occurrence after thyroidectomy, even in facilities with extensive experience in this matter. Compared to total thyroid removal due to benign goitre, surgery for cancer with associated central and lateral lymphadenectomy significantly increases the risk of postoperative hypoparathyroidism. In surgical practice, it is reasonable to conduct routine Ca and PTH level checks after the procedure and 30 days following thyroidectomy

    Level of oxytocin prior to rugby and handball matches: An exploratory study among groups of Polish players

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    The aim of the present exploratory study was to assess the changes in urinary oxytocin (OT) concentration during the period between five days before, and on the day of match, among rugby and handball players. Nine male rugby players with a mean age of 27.62 years (SD = 4.21) and 18 male handball players with a mean age of 17.03 years (SD = 0.57) participated. Urinary oxytocin level was measured by ELISA immunoassay as a ratio to the concentration of creatinine [mg/ml] measured through colorimetric detection. The relative level of OT to creatinine (OT/CRE) significantly differed between the type of player (rugby or handball) but not between times of measurements. Significant differences were only between OT/CRE level in a day of match in rugby players and in 5 days before match in handball players (p<0.05). There was no change in oxytocin levels during the time periods between five days before and on the day of a match, in either of the two kinds of players. The change in oxytocin might be traceable during the match but not before a match and this perhaps depends on a more subtle context of competition, but not on the assumption of competition. Further studies are needed based on more homogenous group with higher number of matches

    The Usefulness of Spectral Mammography in Surgical Planning of Breast Cancer Treatment—Analysis of 999 Patients with Primary Operable Breast Cancer

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    Contrast-enhanced spectral mammography (CESM) is a promising, digital breast imaging method for planning surgeries. The study aimed at comparing digital mammography (MG) with CESM as predictive factors in visualizing multifocal-multicentric cancers (MFMCC) before determining the surgery extent. We analyzed 999 patients after breast cancer surgery to compare MG and CESM in terms of detecting MFMCC. Moreover, these procedures were assessed for their conformity with postoperative histopathology (HP), calculating their sensitivity and specificity. The question was which histopathological types of breast cancer were more frequently characterized by multifocality–multicentrality in comparable techniques as regards the general number of HP-identified cancers. The analysis involved the frequency of post-CESM changes in the extent of planned surgeries. In the present study, MG revealed 48 (4.80%) while CESM 170 (17.02%) MFMCC lesions, subsequently confirmed in HP. MG had MFMCC detecting sensitivity of 38.51%, specificity 99.01%, PPV (positive predictive value) 85.71%, and NPV (negative predictive value) 84.52%. The respective values for CESM were 87.63%, 94.90%, 80.57% and 96.95%. Moreover, no statistically significant differences were found between lobular and NST cancers (27.78% vs. 21.24%) regarding MFMCC. A treatment change was required by 20.00% of the patients from breast-conserving to mastectomy, upon visualizing MFMCC in CESM. In conclusion, mammography offers insufficient diagnostic sensitivity for detecting additional cancer foci. The high diagnostic sensitivity of CESM effectively assesses breast cancer multifocality/multicentrality and significantly changes the extent of planned surgeries. The multifocality/multicentrality concerned carcinoma, lobular and invasive carcinoma of no special type (NST) cancers with similar incidence rates, which requires further confirmation

    The Role of Education for Security in the Context of Cybercrime Threat

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    W niniejszym artykule zaprezentowano wyzwania stojące przed edukacją dla bezpieczeństwa w dobie społeczeństwa informacyjnego i zagrożeń związanych z cyberprzestępczością. W związku ze zmianami technologicznymi, które zachodzą w szybko i gwałtownie zmieniającym się współczesnym społeczeństwie, pojawiają się nowe kategorie zagrożeń dla bezpieczeństwa współczesnego człowieka. W rezultacie skuteczna i efektywna edukacja dla bezpieczeństwa musi reagować na zmiany, które przejawiają się w postaci nowych zagrożeń.This article presents the challenges facing education for security in the era of information society and threats related to cybercrime. Due to technological changes, new categories of threats to the security of modern man appear. As a result, effective and effective education for safety must respond to changes that are manifested in the form of new threats
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