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The impact of different photovoltaic models for a combined solar array and pumped hydro storage system was investigated. Al-Wehda dam located in Harta city in the northern of Jordan was used to validate the approach. The two-diode (TD), single-diode (SD), and ideal single-diode (ISD) solar models were evaluated in terms of the solar array size, reliability, and ecological effects. The impoundment of Al-Wehda dam was taken as the upper reservoir of the pumped hydro facility of the proposed renewable energy system. It was found that the PV power is more accurately modelled by considering the recombination loss in the TD solar model. This leads to a more realistic sizing and precise system evaluation. Results were obtained using the particle swarm optimization (PSO) algorithm and the whale optimization algorithm (WOA) for validation purposes. For instance, the PSO results showed that the realistic TD model is reliable, with an index of reliability of 98.558%. Further, it is the most ecological solution with an annual emissions reduction of 21.5198 Gg. The optimized values are 44,840 solar panels and 65.052 M.m3 of the lower reservoir volume for the TD model. The number of PV panels are reduced by 16.67% and 7.93%, respectively, with the ISD and SD relative to the TD model.

Current voltage characteristics were measured for Cd3Se97 and Cd3Se76S21 thin film samples as a function of temperature and thickness. Static I-V curves of the investigated samples are typical for a memory switch. The mean value of the threshold voltage V¯th increases with film thickness (in the range ≈ (200 - 700nm)) and decreases with increasing temperature (in the range (303 - 365k)) and increases with the addition of sulfur S . The obtained mean value≈ 0.48 of the ratio ϵ/ΔEσ(where e is the threshold voltage activation energy & ?Es, the conduction activation energy) for the investigated compositions agree with the value of 0.5 obtained theoretically on the basis of an electrothermal model. Moreover, the obtained value of ?Tbreakdown for most of the investigated compositions are in the same order with those obtained before. Therefore the switching phenomenon in the investigated compositions can be explained according to the electrothermal model. [ABSTRACT FROM AUTHOR]

Background/objectives: New teaching methods are warranted to meet the demand for increased flexibility in medical education while making optimal use of the limited resources of educators. The COVID-19 pandemic forced universities to resort to online-only teaching, even for training of psychomotor skills. The objectives of this study were: (I) to investigate the performance of students without previous experience in ear, nose and throat (ENT) examination after completing an asynchronous online teaching course in an objective standardized clinical examination (OSCE) and (II) to evaluate the degree of over- and underestimation of their abilities., Methods: The study was designed as a prospective, single-institution medical education cohort study. Medical students (n = 54; 3rd/4th year, no previous head and neck examination skills) completed a comprehensive online training for basic head and neck examination skills 1-14 days before undergoing an OSCE on 5 different examination items (cervical lymph node examination, oral/oropharyngeal examination, otoscopy, Weber/Rinne hearing test, anterior rhinoscopy). Expert-evaluated theoretical knowledge and practical abilities were measured using Likert scales (1 = high proficiency to 5 = low proficiency). Participants self-evaluated their own skills before and after the OSCE (5-point Likert scales)., Results: Students achieved an overall good to medium skill level in basic head and neck examination after online training. Increased psychomotor complexity of tasks contributed to worse performance. Expert evaluation of practical skills was better in male participants and those who rated their preparation as thorough. Low/no misjudgment (discrepancy between self- and expert-evaluation) was observed in most participants, while high discrepancy levels (strong misjudgment) were mainly attributable to the students' underestimation of their own abilities., Conclusions: Online training of head and neck examination skills is a cost- and resource-efficient introduction to skill training and was inevitable during the pandemic. However, it cannot replace practical hands-on training, especially in tasks with high psychomotor requirements. Refresher-courses could compensate for cancelled skill training during the pandemic., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

We aimed to investigate the effects of 18 F-FDG PET voxel intensity normalization on radiomic features of oropharyngeal squamous cell carcinoma (OPSCC) and machine learning-generated radiomic biomarkers. Methods: We extracted 1,037 18 F-FDG PET radiomic features quantifying the shape, intensity, and texture of 430 OPSCC primary tumors. The reproducibility of individual features across 3 intensity-normalized images (body-weight SUV, reference tissue activity ratio to lentiform nucleus of brain and cerebellum) and the raw PET data was assessed using an intraclass correlation coefficient (ICC). We investigated the effects of intensity normalization on the features' utility in predicting the human papillomavirus (HPV) status of OPSCCs in univariate logistic regression, receiver-operating-characteristic analysis, and extreme-gradient-boosting (XGBoost) machine-learning classifiers. Results: Of 1,037 features, a high (ICC ≥ 0.90), medium (0.90 > ICC ≥ 0.75), and low (ICC < 0.75) degree of reproducibility across normalization methods was attained in 356 (34.3%), 608 (58.6%), and 73 (7%) features, respectively. In univariate analysis, features from the PET normalized to the lentiform nucleus had the strongest association with HPV status, with 865 of 1,037 (83.4%) significant features after multiple testing corrections and a median area under the receiver-operating-characteristic curve (AUC) of 0.65 (interquartile range, 0.62-0.68). Similar tendencies were observed in XGBoost models, with the lentiform nucleus-normalized model achieving the numerically highest average AUC of 0.72 (SD, 0.07) in the cross validation within the training cohort. The model generalized well to the validation cohorts, attaining an AUC of 0.73 (95% CI, 0.60-0.85) in independent validation and 0.76 (95% CI, 0.58-0.95) in external validation. The AUCs of the XGBoost models were not significantly different. Conclusion: Only one third of the features demonstrated a high degree of reproducibility across intensity-normalization techniques, making uniform normalization a prerequisite for interindividual comparability of radiomic markers. The choice of normalization technique may affect the radiomic features' predictive value with respect to HPV. Our results show trends that normalization to the lentiform nucleus may improve model performance, although more evidence is needed to draw a firm conclusion., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Background: Intra-ductal cancer (IDC) is the most common type of breast cancer, with intra-lobular cancer (ILC) coming in second. Surgery is the primary treatment for early stage breast cancer. There are now irrefutable data demonstrating that the immune context of breast tumors can influence growth and metastasis. Adjuvant chemotherapy may be administered in patients who are at a high risk of recurrence. Our goal was to identify the processes underlying both types of early local recurrences., Methods: This was a case-control observational study. Within 2 years of receiving adjuvant taxan and anthracycline-based chemotherapy, as well as modified radical mastectomy (MRM), early stage IDC and ILC recurred. Vimentin, α-smooth muscle actin (SMA), platelet-derived growth factor (PDGF), matrix metalloproteinase (MMP1), and clustered differentiation (CD95) were investigated., Results: Of the samples in the ductal type group, 25 showed local recurrence, and 25 did not. Six individuals in the lobular-type group did not experience recurrence, whereas seven did. Vimentin (p = 0.000 and 0.021), PDGF (p = 0.000 and 0.002), and CD95 (p = 0.000 and 0.045) expressions were significantly different in ductal and lobular carcinoma types, respectively. Measurement of ductal type was the sole significant difference found in MMP1 (p = 0.000) and α-SMA (p = 0.000). α-SMA and CD95 were two variables that helped the recurrence mechanism in the ductal type according to the pathway analysis. In contrast, the CD95 route is a recurrent mechanism for the lobular form., Conclusions: While the immune system plays a larger role in ILC, the tumor microenvironment and immune system both influence the recurrence of IDC. According to this study, improving the immune system may be a viable cancer treatment option., (© 2024. The Author(s).)

Although most cases of acute pancreatitis (AP) are minor, severe cases are associated with a substantial risk of death. Acute pancreatitis (AP) is a common illness. Therefore, it is critical to assess AP severity as soon as possible. This review aimed to ascertain the predictive significance of the CRP to albumin ratio in individuals with AP. We searched PubMed, Science Direct, and Cochrane Library electronic databases Until January 2023. Studies that reported the CRP/alb ratio at admission and its relationship to the severity or death of patients with AP were included. Using a random-effects model, we computed the pooled mean difference (MD) and 95% confidence interval (CI). The quality of the included studies was evaluated using the Newcastle-Ottawa scale. This meta-analysis combined data from six trials with a total of 2244 patients. Upon admission, the CRP/alb ratio was higher in patients with severe AP than in those with mild to moderate AP (pooled MD:3.59; 95% CI:2.51-4.68; p<0.00001). Additionally, non-survivor AP patients had a substantially higher CRP/alb ratio than survivor AP patients (pooled MD:2.12; 95% CI:0.43-3.8; p<0.01). Individuals with AP may benefit from a high CRP/ALB ratio as a preliminary indicator of poor prognosis.

Introduction: Oncoplastic breast surgery has become a major player in modern breast surgery.It broadens the indications for breast-conserving surgery. More challenging cases are being treated more with what so-called "extreme oncoplastic breast surgery" which is defined as a breast-conserving operation, using oncoplastic techniques, in a patient who, in most physicians' opinions, requires a mastectomy., Methods: Replacement and/or displacement oncoplastic techniques with contralateral symmetrization to three female patients with breast cancer were done by an oncoplastic breast surgeon., Outcomes: The three patients had smooth recoveries with good aesthetic,oncologic and psychological outcomes., Conclusion: Oncoplastic breast surgery can be a better option than mastectomy with good oncologic, Psychological and aesthetic outcomes, even with extreme cases, yet long-term studies are needed., Competing Interests: The authors declare no conflicts of interest., (© 2022 The Authors. Published by Elsevier Ltd on behalf of IJS Publishing Group Ltd.)

With over 500 million confirmed cases and 6.2 million deaths worldwide, the novel coronavirus has highlighted the underlying disparities in healthcare, unpreparedness to deal with a new disease and the need for monitoring and surveillance for a post-infectious syndrome as well as complicated diseases. Initially, children were thought to be spared but reports of a new phenomenon manifesting as Kawasaki-like disease, toxic shock syndrome, and multi-system inflammatory syndrome, which developed after a few weeks of severe COVID-19 infection, emerged in the pediatric population. As the pandemic progressed, increased prevalence of multi-system inflammatory syndrome in children (MIS-C) related to COVID-19 was seen in non-Hispanic blacks, Asians, and Latinos as compared to the white population drawing attention to a possible role of ethnicity and socio-economic disparities. The CDC currently reports that 31% of MIS-C cases were seen in Black Non-Hispanics and 26% in Latinos, who were historically more affected in previous pandemics. Furthermore, MIS-C cases in developing countries showed higher mortality as compared to high-income countries, which points toward the role of social determinants of health and limitations in a low-resource set up in increasing the disease burden of MIS-C, which should be treated as a public health emergency. Our review highlights the role of ethnicity, socio-economic factors, comorbidities, and differences in populations affected by MIS-C in high-income vs. low- and middle-income countries., Competing Interests: Author AN is employed by Hamad Medical Corporation. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Asghar, Sharaf, Butt, Shaikh, Shekha, Waris, Ullah and Nashwan.)

In medical school, practical capacity building is a central goal. During the COVID-19 pandemic, a shift to online teaching methods in university was mandated in many countries to reduce risk of SARS-CoV-2 transmission. This severely affected the teaching of psychomotor ability skills such as head and neck examination skills, resulting in a share of students that have only been taught such ENT-specific examination skills with online courses; our study aimed to measure performance and capacity of self-evaluation in these students. After completing a new extensive online Ear Nose Throat (ENT) examination course, we conducted a standardized clinical skills exam for nine different ENT examination items with 31 students. Using Likert scales, self-evaluation was based on questionnaires right before the clinical skills exam and objective evaluation during the exam was assessed following a standardized regime. Self-evaluation and objective evaluation were correlated. To compare the exclusive online teaching to traditional hands-on training, a historic cohort with 91 students was used. Objective examination performance after in-classroom or online teaching varied for single examination items while overall assessment remained comparable. Overall, self-evaluation did not differ significantly after online-only and in-classroom ENT skill teaching. Nevertheless, misjudgment of one's skill level increased after online-only training compared to in-classroom teaching. Highest levels of overestimation were observed after online training in simple tasks. While gender and interest in ENT did not influence self-evaluation and misjudgment, higher age of participants was associated with an overestimation of skills. Medical students with online-only training during the COVID-19 pandemic achieved similar ENT examination skills to those with traditional on-campus training before the pandemic. Nevertheless, students with online-only training were more prone to misjudge their skills when they assessed their skills. Due to the COVID-19 pandemic, current medical students and graduates might therefore lack individual specific psychomotor skills such as the ENT examination, underlining the importance of presence-based teaching.

Cancer stem cells (CSCs) are accountable for the progress of head and neck squamous cell carcinoma (HNSCC). This exploratory study evaluated the expression of molecular CSC markers in different tissues of HNSCC patients. Tissue specimens of primary tumor, lymph node metastases and macroscopically healthy mucosa of 12 consecutive HNSCC patients, that were treated with surgery and adjuvant radio(chemo)therapy upon indication, were collected. Samples were assessed for the expression of p16 as a surrogate for HPV-related disease and different molecular stem cell markers (ALDH1A1, BCL11B, BMI-1, and CD44). In the cohort, seven patients had HPV-related HNSCC; six thereof were oropharyngeal squamous cell carcinoma. While expression of BMI-1 and BCL11B was significantly lower in healthy mucosa than both tumor and lymph node metastasis, there were no differences between tumor and lymph node metastasis. In the HPV-positive sub-cohort, these differences remained significant for BMI-1. However, no significant differences in these three tissues were found for ALDH1A1 and CD44. In conclusion, this exploratory study shows that CSC markers BMI-1 and BCL11B discriminate between healthy and cancerous tissue, whereas ALDH1A1 and CD44 were expressed to a comparable extent in healthy mucosa and cancerous tissues.

Human adipose-derived stem/stromal cells (ASCs) are increasingly used as auto-transplants in regenerative medicine to restore tissue defects or induce wound healing, especially in cancer patients. The impact of ASCs on squamous cell carcinoma of the upper aerodigestive tract (UAT) including head and neck and esophageal squamous cell carcinoma (HNSCC and ESCC) is not yet fully understood. ASCs were cultured from subcutaneous, abdominal lipoaspirates of five patients, who received auto-transplants to the head and neck. Supernatants were tested for paracrine effects in functional in vitro assays of proliferation of HNSCC tumor cell line FaDu and ESCC cell line Kyse30, and their cell migration/invasion capacities in Boyden chambers, in addition to endothelial tube formation assay using human umbilical vein endothelial cells (HUVECs). All ASC-derived supernatants enhanced proliferation of FaDu cells, invasive migration, and tube formation by HUVECs, compared to controls. Of five patients' lipoaspirates, ASC-derived supernatants of four patients increased proliferation and invasive migration in Kyse30 cells. The data suggests that ASCs can promote tumor cell proliferation, invasiveness, and neo-angiogenesis in these tumor cell lines of the UAT and HUVEC in a paracrine manner. Although clinical studies on the subject of oncological safety are still needed, these findings emphasize the importance of complete tumor removal before ASCs are used in the head and neck.

Locoregional failure remains a therapeutic challenge in oropharyngeal squamous cell carcinoma (OPSCC). We aimed to devise novel objective imaging biomarkers for prediction of locoregional progression in HPV-associated OPSCC. Following manual lesion delineation, 1037 PET and 1037 CT radiomic features were extracted from each primary tumor and metastatic cervical lymph node on baseline PET/CT scans. Applying random forest machine-learning algorithms, we generated radiomic models for censoring-aware locoregional progression prognostication (evaluated by Harrell's C-index) and risk stratification (evaluated in Kaplan-Meier analysis). A total of 190 patients were included; an optimized model yielded a median (interquartile range) C-index of 0.76 (0.66-0.81; p = 0.01) in prognostication of locoregional progression, using combined PET/CT radiomic features from primary tumors. Radiomics-based risk stratification reliably identified patients at risk for locoregional progression within 2-, 3-, 4-, and 5-year follow-up intervals, with log-rank p-values of p = 0.003, p = 0.001, p = 0.02, p = 0.006 in Kaplan-Meier analysis, respectively. Our results suggest PET/CT radiomic biomarkers can predict post-radiotherapy locoregional progression in HPV-associated OPSCC. Pending validation in large, independent cohorts, such objective biomarkers may improve patient selection for treatment de-intensification trials in this prognostically favorable OPSCC entity, and eventually facilitate personalized therapy., Competing Interests: Declaration of Competing Interest SPH: None declared. KS: None declared. TZ: None declared. PB: None declared. CR: None declared. RF has acted as speaker and consultant for GE Healthcare and has a research agreement (beta tester) and support from GE Healthcare. RF is also a founder and stockholder of 4intelligent Inc.; and a clinical research scholar (chercheur-boursier clinician) supported by the Fonds de recherche en santé du Québec (FRQS). BHK: None declared. AP: None declared. BLJ: None declared. MLP: None declared. CL has research agreements with Siemens Medical Solutions and GE Healthcare. BB: None declared. AM: None declared. SP: None declared., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Accurate risk-stratification can facilitate precision therapy in oropharyngeal squamous cell carcinoma (OPSCC). We explored the potential added value of baseline positron emission tomography (PET)/computed tomography (CT) radiomic features for prognostication and risk stratification of OPSCC beyond the American Joint Committee on Cancer (AJCC) 8th edition staging scheme. Using institutional and publicly available datasets, we included OPSCC patients with known human papillomavirus (HPV) status, without baseline distant metastasis and treated with curative intent. We extracted 1037 PET and 1037 CT radiomic features quantifying lesion shape, imaging intensity, and texture patterns from primary tumors and metastatic cervical lymph nodes. Utilizing random forest algorithms, we devised novel machine-learning models for OPSCC progression-free survival (PFS) and overall survival (OS) using "radiomics" features, "AJCC" variables, and the "combined" set as input. We designed both single- (PET or CT) and combined-modality (PET/CT) models. Harrell's C-index quantified survival model performance; risk stratification was evaluated in Kaplan-Meier analysis. A total of 311 patients were included. In HPV-associated OPSCC, the best "radiomics" model achieved an average C-index ± standard deviation of 0.62 ± 0.05 ( p = 0.02) for PFS prediction, compared to 0.54 ± 0.06 ( p = 0.32) utilizing "AJCC" variables. Radiomics-based risk-stratification of HPV-associated OPSCC was significant for PFS and OS. Similar trends were observed in HPV-negative OPSCC. In conclusion, radiomics imaging features extracted from pre-treatment PET/CT may provide complimentary information to the current AJCC staging scheme for survival prognostication and risk-stratification of HPV-associated OPSCC.

Background/aim: The incidence of human papilloma virus (HPV)-related head and neck squamous cell carcinoma (HNSCC) has been increasing in the last decades. Analysis of oral brushing or rinsing samples for screening or stratification could potentially improve screening and prevention., Patients and Methods: Oral brushes and mouthwashes were taken from 20 patients with HPV-associated HNSCC before definite therapy. HPV genotyping was performed for the detection of 14 high-risk HPV subtypes and correlated to DNA isolated from tumor tissue., Results: Ten of 20 patients were tested HPV positive by using either method. There was a significant correlation between macroscopic visibility of tumor and positive HPV detection (p<0.001) and HPV detection and tumor size (p<0.001). HPV was detected in all macroscopically visible tumors. Half of the HPV cases who had macroscopically invisible tumors were missed by both methods., Conclusion: Both techniques are limited in the detection of macroscopically non-visible and small tumors. Therefore, the application of these techniques for screening or diagnosis of HNSCC is not recommended., (Copyright© 2020, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Acute appendicitis is the most common surgical condition with which patients present in emergency departments worldwide. It is also a rare cause of intestinal obstruction. Here, we report a case of a 53-year-old man who presented with a clinical picture of mechanical small bowel obstruction. Leucocytosis was not demonstrated on the routine blood investigation in our case, in contrast to the findings for most patients with acute appendicitis. Acute appendicitis, as the cause of the intestinal obstruction, was diagnosed by computed tomography of the abdomen. The patient was treated using diagnostic laparoscopy and laparoscopic appendectomy. This case was compared with those previously reported in the medical literature to determine the frequency of the case and the surgical management.

Under steady-state conditions, aged neutrophils are removed from the circulation in bone marrow, liver, and spleen, thereby maintaining myeloid cell homeostasis. The fate of these aged immune cells under inflammatory conditions, however, remains largely obscure. Here, we demonstrate that in the acute inflammatory response during endotoxemia, aged neutrophils cease returning to the bone marrow and instead rapidly migrate to the site of inflammation. Having arrived in inflamed tissue, aged neutrophils were found to exhibit a higher phagocytic activity as compared with the subsequently recruited nonaged neutrophils. This distinct behavior of aged neutrophils under inflammatory conditions is dependent on specific age-related changes in their molecular repertoire that enable these "experienced" immune cells to instantly translate inflammatory signals into immune responses. In particular, aged neutrophils engage Toll-like receptor-4- and p38 MAPK-dependent pathways to induce conformational changes in β2 integrins that allow these phagocytes to effectively accomplish their mission in the front line of the inflammatory response. Hence, ageing in the circulation might represent a critical process for neutrophils that enables these immune cells to properly unfold their functional properties for host defense., (© 2016 by The American Society of Hematology.)

Objective: Betahistine is a histamine H(1)-receptor agonist and H(3)-receptor antagonist that is administered to treat Menière's disease. Despite widespread use, its pharmacological mode of action has not been entirely elucidated. This study investigated the effect of betahistine on guinea pigs at dosages corresponding to clinically used doses for cochlear microcirculation., Methods: Thirty healthy Dunkin-Hartley guinea pigs were randomly assigned to five groups to receive betahistine dihydrochloride in a dose of 1,000 mg/kg b. w. (milligram per kilogram body weight), 0.100 mg/kg b. w., 0.010 mg/kg b. w., 0.001 mg/kg b. w. in NaCl 0.9% or NaCl 0.9% alone as placebo. Cochlear blood flow and mean arterial pressure were continuously monitored by intravital fluorescence microscopy and invasive blood pressure measurements 3 minutes before and 15 minutes after administration of betahistine., Results: When betahistine was administered in a dose of 1.000 mg/kg b. w. cochlear blood flow was increased to a peak value of 1.340 arbitrary units (SD: 0.246; range: 0.933-1.546 arb. units) compared to baseline (p<0.05; Two Way Repeated Measures ANOVA/Bonferroni t-test). The lowest dosage of 0.001 mg/kg b. w. betahistine or NaCl 0.9% had the same effect as placebo. Nonlinear regression revealed that there was a sigmoid correlation between increase in blood flow and dosages., Conclusions: Betahistine has a dose-dependent effect on the increase of blood flow in cochlear capillaries. The effects of the dosage range of betahistine on cochlear microcirculation corresponded well to clinically used single dosages to treat Menière's disease. Our data suggest that the improved effects of higher doses of betahistine in the treatment of Menière's disease might be due to a corresponding increase of cochlear blood flow.