Primary mediastinal choriocarcinoma masquerading as lung metastasis: a rare disease with a fatal outcome

Background: Most germ cell tumors eg. choriocarcinomas are located in the gonads, however about 2–5% arise from extragonadal regions, such as the mediastinum, retroperitoneum, and central nervous system. Non-gestational choriocarcinoma in mediastinum without a detectable primary in the gonads is termed primary mediastinal choriocarcinoma. Materials and method: Contrast-enhanced whole body computed tomography scan and correlated with tumour markers such as beta human chorionic gonadotropin are used to assess the mediastinal mass. Confirmation of diagnosis was made with image guided biopsy, histopathological examination and special staining. Results: Primary mediastinal choriocarcinoma was confirmed by lack of testicular lesion on ultrasound examination and presence of mediastinal mass with multiple metastatic lesions. Confirmation by CKAE1/AE3 (immunohistochemical study) positive which showed presence of multinucleated epithelial cells. Conclusion: Contrast-enhanced computed tomography is useful tool to diagnose this condition as also provide image guided access for biopsy. In correlation with tumour markers investigation and special immunohistochemical studies can help to clinch the diagnosis

A systematical characterization of teo2–v2o5 glass system using boron (Iii) oxide and neodymium (iii) oxide substitution: Resistance behaviors against ionizing radiation

This study aimed to performan extensive characterization of a 74.75TeO2–0.25V2O5–(25 - x)B2O3-xNd2O3 glass system with (x = 0, 0.5, 1.0, and 1.5 mol%) for radiation shielding properties. Linear and mass attenuation coefficients were determined using Phy-X PSD software and compared with the simulation using Monte Carlo software MCNPX (version 2.7.0). Half value layer, mean free path, tenth value layer, effective atomic number, exposure buildup factor, and energy absorption buildup factors of VTBNd0.0, VTBNd0.5, VTBNd1.0, and VTBNd1.5 glasses were determined, respectively. The results showed that boron (III) oxide and neodymium (III) oxide substitution has an obvious impact on the gamma ray attenuation properties of the studied glasses. It can be concluded that the VTBNd1.5 sample with the highest content of neodymium (III) oxide (1.5 mol%) is the superior sample for shielding of gamma radiation in the investigated energy range. © 2021 by the authors

The influence of heavy elements on the ionizing radiation shielding efficiency and elastic properties of some tellurite glasses: Theoretical investigation

The impact of adding PbO and WO3 on the mechanical properties and radiation shielding efficiency of 4 different glass samples labeled as TWP1, TWP2, TWP3, and TWP4 (samples codes) was studied via the Makishima and Mackenzie model (MMD), Rocherulle model (RD), XCOM database, FLUKA code, and Phys-X/PSD software. According to MMD, Young's (Y), bulk (K), shear (G) modulus values increase from 59.13 to 62.80 GPa, from 37.76 to 43.86 GPa, from 25.48 to 26.55 GPa, and from 71.73 to 79.26 GPa for TWP1 and TWP4 glasses, respectively. 277.833, 358.768, 465.048 and 570.786 cm−1 values are the highest linear attenuation coefficient (μ) values for TWP1, TWP2, TWP3 and TWP4 glasses at 0.015 MeV. The results refer that the TWP4 glass sample has the highest radiation shielding and mechanical properties. The results indicated that the addition of lead and tungsten to the investigated samples improves their elastic and radiation shielding properties. Thus, the TWP4 sample is the best compared to the other glass samples. © 2020 The Author

Cadmium oxide reinforced 46V2O5–46P2O5–(8−x)B2O3–xCdO semiconducting oxide glasses and resistance behaviors against ionizing gamma rays

This study aimed to determine the contribution of B2O3/CdO substitution on gamma-ray attenuation behaviors of 46V2O5–46P2O5–(8−x)B2O3–xCdO (x = 0–8 mol%) glass system. Accordingly, attenuation coefficients along with half and tenth value layers of five different samples were determined in 0.015 MeV–15 MeV photon energy range. Moreover, effective atomic numbers and effective atomic weight along with exposure and energy absorption buildup factors were determined in same energy range. The result showed that B2O3/CdO substitution has a direct effect on behaviors of studied semiconducting oxide glasses against ionizing gamma-rays. Our findings showed that increasing CdO reinforcement has an obvious impact on gamma-ray attenuation properties especially in the low energy range, where photoelectric effect dominates the photon–matter interaction. Moreover, half-value layer, mean-free path and tenth value layer also decrease with an increase in the content of CdO in the composition. Consequently, VPBCd8 sample with 8% mole CdO additive was reported with the minimum half-value layer, the mean-free path, tenth value layer exposure build-up factor and energy absorption build-up factors. The outcomes would be useful for scientific community to observe the most suitable substitution type along with related semiconducting oxide glass composition to provide the aforementioned shielding properties in terms of needs and utilization requirements. © 2021 The AuthorsThe authors thank Taif University Researchers Supporting Project number (TURSP-2020/12), Taif University, Taif, Saudi Arabia

Individual identification via electrocardiogram analysis

Background: During last decade the use of ECG recordings in biometric recognition studies has increased. ECG characteristics made it suitable for subject identification: it is unique, present in all living individuals, and hard to forge. However, in spite of the great number of approaches found in literature, no agreement exists on the most appropriate methodology. This study aimed at providing a survey of the techniques used so far in ECG-based human identification. Specifically, a pattern recognition perspective is here proposed providing a unifying framework to appreciate previous studies and, hopefully, guide future research. Methods: We searched for papers on the subject from the earliest available date using relevant electronic databases (Medline, IEEEXplore, Scopus, and Web of Knowledge). The following terms were used in different combinations: electrocardiogram, ECG, human identification, biometric, authentication and individual variability. The electronic sources were last searched on 1st March 2015. In our selection we included published research on peer-reviewed journals, books chapters and conferences proceedings. The search was performed for English language documents. Results: 100 pertinent papers were found. Number of subjects involved in the journal studies ranges from 10 to 502, age from 16 to 86, male and female subjects are generally present. Number of analysed leads varies as well as the recording conditions. Identification performance differs widely as well as verification rate. Many studies refer to publicly available databases (Physionet ECG databases repository) while others rely on proprietary recordings making difficult them to compare. As a measure of overall accuracy we computed a weighted average of the identification rate and equal error rate in authentication scenarios. Identification rate resulted equal to 94.95 % while the equal error rate equal to 0.92 %. Conclusions: Biometric recognition is a mature field of research. Nevertheless, the use of physiological signals features, such as the ECG traits, needs further improvements. ECG features have the potential to be used in daily activities such as access control and patient handling as well as in wearable electronics applications. However, some barriers still limit its growth. Further analysis should be addressed on the use of single lead recordings and the study of features which are not dependent on the recording sites (e.g. fingers, hand palms). Moreover, it is expected that new techniques will be developed using fiducials and non-fiducial based features in order to catch the best of both approaches. ECG recognition in pathological subjects is also worth of additional investigations

In Silicon Monte Carlo Simulation Trials for Investigation of V2O5 Reinforcement Effect on Ternary Zinc Borate Glasses: Nuclear Radiation Shielding Dynamics

In the current study, promising glass composites based on vanadium pentoxide (V2O5)- doped zinc borate (ZnB) were investigated in terms of their nuclear-radiation-shielding dynamics. The mass and linear attenuation coefficient, half-value layer, mean free path, tenth-value layer, effective atomic number, exposure-buildup factor, and energy-absorption-buildup factor were deeply simulated by using MCNPX code, Phy-X PSD code, and WinXcom to study the validation of ZBV1, ZBV2, ZBV3, and ZBV4 based on (100−x)(0.6ZnO-0.4B2O3)(x)(V2O5) (x = 1, 2, 3, 4 mol%) samples against ionizing radiation. The results showed that attenuation competencies of the studied glasses slightly changed while increasing the V2O5 content from 1 mol% to 4 mol%. The domination of ZnO concentration in the composition compared to B2O3 makes ZnO substitution with V2O5 more dominant, leading to a decrease in density. Since density has a significant role in the attenuation of gamma rays, a negative effect was observed. It can be concluded that the aforementioned substitution can negatively affect the shielding competencies of studied glasses. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Multiple characterization of some glassy-alloys as photon and neutron shields: In-silico Monte Carlo investigation

In the present work, the nuclear radiation shielding proficiency of eight glassy alloys (Gd25RE25Co25Al25 (RE = Tb, Dy and Ho)) containing different amounts of rare earth elements was investigated with MCNPX simulation codes. Mass attenuation coefficients (μ/ρ) of the glassy alloys were simulated in the energy interval of 0.2-20 MeV by exploiting MCNPX codes, and the generated data were found to match with theoretical WinXCOM results. Next, other crucial photon attenuation parameters, effective atomic number (Zeff), Half Value Layer (HVL), and Mean Free Path (MFP), were gotten out using μ/ρ values. It was seen that Er20Tm20 and Er20Tb20 samples replaced with Er by Gd had the highest Zeff and μ/ρ values, whereas HVL and MFP values were the smallest among the other glassy alloys. Geometric progression (GP) procedure was enjoyed to achieve the exposure and energy absorption buildup factors (EBF and EABF) for the glassy alloys proposed. EABFs and EBFs took the largest and lowest values for Gd25Tb25 and Er20Tm20, respectively, to the other samples. Furthermore, the glassy alloys' neutron reduction abilities were estimated by acquiring fast neutron removal cross-sections (∑R). It was noticed that the ∑R values of the glassy alloys are increased with the rising sample density and seen to be comparable to ∑R values of water and ordinary concrete. The results obtained from this study are important in that they show that glassy alloys can be used as radiation shielding. © 2021 The Author(s). Published by IOP Publishing Ltd

Developed selenium dioxide-based ceramics for advanced shielding applications: Au2O3 impact on nuclear radiation attenuation

The current research article aims to study the radiation shielding competence of a newly developed PbO-B2O3-SeO2-Er2O3:Au2O3 glass ceramic. The concentrations of the constituent oxides were 40, 10, 49.5, and 0.5 mol % for PbO, B2O3, SeO2, and Er2O3, respectively. The studied ceramic specimens were denoted by EA0, EA25, EA50, EA75 and EA100, and their density values were 5.87, 5.92, 5.94, 6.09, and 6.10 g/cm3, respectively. The radiation shielding competence and photon buildup factors of the present ceramics were investigated under the Au2O3/SeO2 substitution with ratio up to 0.1 mol %. The obtained results reveal that the MAC values were reported with 0.233 cm2/g difference between the minimum and the maximum Au2O3 reinforced samples. The highest MAC values were reported for EA100 sample, which has the highest Au2O3 additive in its chemical structure. At 4 MeV photon energy, HVL values were reported as 3.2658 cm, 3.2352 cm, 3.2212 cm, 3.139 cm and 3.1309 cm for EA0, EA25, EA50, EA75 and EA100, respectively. Moreover, the highest values of EBF were observed for the EA100, and the lowest values of EBF were observed for EA0. Therefore, it can be concluded that the present ceramics possess high level shielding competence to use for various applications of gamma radiation. © 2021The authors extend their appreciation to the Deanship of Scientific Research at King Khalid University for the financial support through research groups program under grant number (R.G.P2/98/41)

Promising applicable heterometallic Al2O3/PbO2 nanoparticles in shielding properties

Hetrometal oxides of (1 - x)Al2O3/xPbO2(NPs) nanoparticles with different PbO2content(x = 0, 0.3, 0.4, 0.5, 0.6 and 0.7) have been prepared by irradiation method. The NPs powder hasbeen checked by X-ray diffraction (XRD). XRD measurements affirmed the presence of bothpure NPs and nanocomposites of (1 - x)Al2O3/xPbO2NPs with different PbO2contents. Thecalculated structural parameters which using the experimental result of XRD charts to givea complete image of these measurements. Moreover, the results using FLUKA code showedthat the values attenuation coefficient (_m), high effective atomic number (Zeff) and neu-tron shielding parameters increase as the lead dioxide increase in the Al2O3/PbO2samples.While the values of half-value layer (HVL) and mean free path (MFP) decrease with increas-ing PbO2content. The investigated shielding features of the chosen Al2O3/PbO2would beadvantageous for exposure control. © 2020 The Authors.The authors extended their appreciation to the Deanship of Scientific Research at King Khalid University for funding this work through the research group program under grant number R.G.P.2/33/41

Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks