Application of the method of parallel trajectories on modeling the dynamics of COVID-19 third wave.

In this paper, we present a new method for successfully simulating the dynamics of COVID-19, experimentally focusing on the third wave. This method, namely, the Method of Parallel Trajectories (MPT), is based on the recently introduced self-organized diffusion model. According to this method, accurate simulation of the dynamics of the COVID-19 infected population evolution is accomplished by considering not the total data for the infected population, but successive segments of it. By changing the initial conditions with which each segment of the simulation is produced, we achieve close and detailed monitoring of the evolution of the pandemic, providing a tool for evaluating the overall situation and the fine-tuning of the restrictive measures. Finally, the application of the proposed MPT on simulating the pandemic's third wave dynamics in Greece and Italy is presented, verifying the method's effectiveness.

Criticality in epidemic spread: An application in the case of COVID19 infected population.

Recently, it has been successfully shown that the temporal evolution of the fraction of COVID-19 infected people possesses the same dynamics as the ones demonstrated by a self-organizing diffusion model over a lattice, in the frame of universality. In this brief, the relevant emerging dynamics are further investigated. Evidence that this nonlinear model demonstrates critical dynamics is scrutinized within the frame of the physics of critical phenomena. Additionally, the concept of criticality over the infected population fraction in epidemics (or a pandemic) is introduced and its importance is discussed, highlighting the emergence of the critical slowdown phenomenon. A simple method is proposed for estimating how far away a population is from this "singular" state, by utilizing the theory of critical phenomena. Finally, a dynamic approach applying the self-organized diffusion model is proposed, resulting in more accurate simulations, which can verify the effectiveness of restrictive measures. All the above are supported by real epidemic data case studies.

Acute partial passive stretching increases range of motion and muscle strength.

AIM: The purpose of this study was to investigate the effects of partial passive stretching (PPS) on peak torque (PT) and joint range of motion (ROM) in healthy subjects. METHODS: Twenty-two males (mean age 20.4±1.0 yrs, height 181.1±4.2 cm and weight 75.8±6.8 kg) participated in the study. Quadriceps and hamstrings PT at different angular velocities was obtained on an isokinetic dynamometer. Standing leg method hop was tested for the stretched and unstretched leg. Each subject performed PPS for 20 seconds. The stretching procedure was repeated 5 times for each muscle group. The whole stretching program lasted for 6 minutes and 20 seconds followed by 5 seconds resting period. RESULTS: Directly after the stretching procedure significant increases were observed of PT in quadriceps and hamstrings, however, only at 300o.s⁻¹ (P<0.05). Joint ROM was increased in all subjects (P<0.05). The distance in single length hop was increased significantly in the stretched leg following stretching (P<0.05). No changes were observed in the unstretched leg. CONCLUSION: Our results indicated that the PPS altered ROM, maximal concentric isokinetic strength at high angle velocities and single length hop only for the stretched leg. These findings suggest that PPS may be an effective technique for enhancing muscle performance.

A boundary value problem of heat transfer within DBD-based plasma jet setups.

We claim an analytical solution for the thermal boundary value problem that arises in DBD-based plasma jet systems as a preliminary and consistent approach to a simplified geometry. This approach involves the outline of a coaxial plasma jet reactor and the consideration of the heat transfer to the reactor solids, namely, the dielectric barrier and the grounded electrode. The non-homogeneous initial and boundary value thermal problem is solved analytically, while a simple cut-off technique is applied to deal with the appearance of infinite series relationships, being the outcome of merging dual expressions. The results are also implemented numerically, supporting the analytical solution, while a Finite Integration Technique (FIT) is used for the validation. Both the analytical and numerical data reveal the temperature pattern at the cross-section of the solids in perfect agreement. This analytical approach could be of importance for the optimization of plasma jet systems employed in tailored applications where temperature-sensitive materials are involved, like in plasma biomedicine.

Dynamic measurement of the force required to move a liquid drop on a solid surface.

We measured the forces required to slide sessile drops over surfaces. The forces were measured by means of a vertical deflectable capillary stuck in the drop. The drop adhesion force instrument (DAFI) allowed the investigation of the dynamic lateral adhesion force of water drops of 0.1 to 2 µL volume at defined velocities. On flat PDMS surfaces, the dynamic lateral adhesion force increases linearly with the diameter of the contact area of the solid-liquid interface and linearly with the sliding velocity. The movement of the drop relative to the surfaces enabled us to resolve the pinning of the three-phase contact line to individual defects. We further investigated a 3D superhydrophobic pillar array. The depinning of the receding part of the rim of the drop occurred almost simultaneously from four to five pillars, giving rise to peaks in the lateral adhesion force.

Trastuzumab beyond progression in HER2-positive advanced breast cancer: the Royal Marsden experience.

BACKGROUND: Recent UK clinical guidance advises against continuing trastuzumab (T) beyond disease progression (PD) in the absence of brain metastases in patients with HER-2 positive (+ve) advanced breast cancer .We have retrospectively evaluated the outcome of patients with HER-2+ve locally advanced (LA) or metastatic breast cancer (MBC) who continued T beyond PD, treated in our unit. METHODS: All HER-2+ve patients on our prospectively maintained database with LA or MBC who received T beyond PD after adjuvant or one line of T for advanced disease were assessed for response and outcome. From the timepoint of T continuation beyond PD, we calculated the overall disease control rate, time to progression (TTP), and overall survival (OS). RESULTS: One hundred and fourteen patients with HER-2+ve LA or MBC treated with T beyond PD were identified. The main site of disease was visceral in 84 (74%) patients. Seventy-six (66%) had one line of chemotherapy before continuation of T beyond PD and 21 (19%) had two or more. Post-progression, 66 (58%) received T combined with chemotherapy. Of the 93 (82%) patients with documented clinical or radiological response evaluation, 67 (59%) were considered as having stable disease or better. The median TTP was 24 weeks (95% CI: 21-28) and the median OS was 19 months (95% CI: 12-24). CONCLUSION: Our results from an unselected group of patients provide additional evidence that continuation of T beyond PD is of clinical benefit.

Prostate sarcomatoid carcinoma as accidental finding in transurethral resection of prostate specimen. A case report and systematic review of current literature.

BACKGROUND: Sarcomatoid carcinoma of the prostate is an extremely rare and highly aggressive neoplasm that accounts for less than 0.1% of primary prostate malignancies. Long-term survival rates for adult patients with prostate sarcomatoid carcinoma are poor. Surgical treatment seems to be the most effective therapeutic approach. In contrast radiation therapy alone has shown limited efficacy. AIM: The purpose of the study is to present a case of sarcomatoid carcinoma of the prostate treated with a combination of radiotherapy and TURP. CASE REPORT: A 76-year-old man treated with TURP due to acute urinary retention was finally diagnosed with sarcomatoid carcinoma upon pathology examination of the surgical specimen. Patient was initially treated with external beam radiotherapy. Six months later, he presented with urinary retention suggesting extension of the tumor into the bladder neck. Pathology report diagnosed prostate sarcomatoid carcinoma containing also large areas of necrosis. Patient underwent an extensive TURP and he received a second round radiotherapy. One year after the initial diagnosis of sarcomatoid carcinoma, patient is free of symptoms and follow up investigation shows no evidence of metastatic disease. CONCLUSIONS: Radiation therapy in combination with extensive TURP may delay disease progression.

Stemless reverse total shoulder arthroplasty: a systematic review of contemporary literature.

PURPOSE: Reverse shoulder prostheses are increasingly used for treatment of rotator cuff tear arthropathy and other degenerative shoulder diseases. In recent years, aiming for bone stock preservation has led to the design of metaphyseal humeral components without a stem. The aims of this study were to evaluate the complication and reintervention rates, as well as the clinical and radiographic outcomes in patients who underwent reverse shoulder arthroplasty (RSA) with stemless implants. METHODS: A systematic review of the literature was completed until May 2020 using PubMed, EMBASE, CINAHL and Cochrane databases, according to PRISMA guidelines. RESULTS: The literature search revealed 2942 studies, of which 13 were included in this review, with a total of 517 patients and a mean follow-up between 6.4 and 101.6 months. The total complication rate was 6.5%, while 3.3% were humeral associated complications. Finally, the rate of shoulders that underwent a reintervention was 6.7%, with 1.4% relating to a humeral component reason. Stemless RSA led to substantial improvements in patient reported outcome measures and range of motion across all studies. Scapular notching was reported in 15.2%, and lucencies around humeral component were reported in 0.8% of shoulders. CONCLUSION: Stemless RSA resulted in low complication and reintervention rates at the mid-term follow-up. The reported clinical and radiological outcomes showed that these prostheses have at least equivalent outcomes with their stemmed counterparts. Further studies are required to investigate the long-term longevity and performance of the stemless humeral implants. LEVEL OF EVIDENCE: Level IV; Systematic Review.

Comparison of perfused volume segmentation between cone-beam CT and 99mTc-MAA SPECT/CT for treatment dosimetry before selective internal radiation therapy using 90Y-glass microspheres.

PURPOSE: To compare the reliability and accuracy of the pre-treatment dosimetry predictions using cone-beam computed tomography (CBCT) versus 99mTc-labeled macroaggregated albumin (MAA) SPECT/CT for perfused volume segmentation in patients with hepatocellular carcinoma treated by selective internal radiation therapy (SIRT) using 90Y-glass microspheres. MATERIALS AND METHODS: Fifteen patients (8 men, 7 women) with a mean age of 68.3±10.5 (SD) years (range: 47-82 years) who underwent a total of 17 SIRT procedures using 90Y-glass microspheres for unresectable hepatocellular carcinoma were retrospectively included. Pre-treatment dosimetry data were calculated from 99mTc-MAA SPECT/CT using either CBCT or 99mTc-MAA SPECT/CT to segment the perfused volumes. Post-treatment dosimetry data were calculated using 90Y imaging (SPECT/CT or PET/CT). The whole liver, non-tumoral liver, and tumor volumes were segmented on CT or MRI data. The mean absorbed doses of the tumor (DT), non-tumoral liver, perfused liver (DPL) and perfused non-tumoral liver were calculated. Intra- and interobserver reliabilities were investigated by calculating Lin's concordant correlation coefficients (ρc values). The differences (biases) between pre- and post-treatment dosimetry data were assessed using the modified Bland-Altman method (for non-normally distributed variables), and systematic bias was evaluated using Passing-Bablok regression. RESULTS: The intra- and interobserver reliabilities were good-to-excellent (ρc: 0.80-0.99) for all measures using both methods. Compared with 90Y imaging, the median differences were 5.8Gy (IQR: -12.7; 16.1) and 5.6Gy (IQR: -13.6; 10.2) for DPL-CBCT and DPL-99mTc-MAA SPECT/CT, respectively. The median differences were 1.6Gy (IQR: -29; 7.53) and 9.8Gy (IQR: -28.4; 19.9) for DT-CBCT and DT-99mTc-MAA SPECT/CT respectively. Passing-Bablok regression analysis showed that both CBCT and 99mTc-MAA SPECT/CT had proportional biases and thus tendencies to overestimate DT and DPL at higher post-treatment doses. CONCLUSION: CBCT may be a reliable segmentation method, but it does not significantly increase the accuracy of dose prediction compared with that of 99mTc-MAA SPECT/CT. At higher doses both methods tend to overestimate the doses to tumors and perfused livers.

Modelling the electric field in reactors yielding cold atmospheric-pressure plasma jets.

The behavior of the electric field in Cold Atmospheric-Pressure Plasma jets (CAPP jets) is important in many applications related to fundamental science and engineering, since it provides crucial information related to the characteristics of plasma. To this end, this study is focused on the analytic computation of the electric field in a standard plasma reactor system (in the absence of any space charge), considering the two principal configurations of either one-electrode or two-electrodes around a dielectric tube. The latter is considered of minor contribution to the field calculation that embodies the working gas, being an assumption for the current research. Our analytical technique employs the cylindrical geometry, properly adjusted to the plasma jet system, whereas handy subdomains separate the area of electric activity. Henceforth, we adapt the classical Maxwell's potential theory for the calculation of the electric field, wherein standard Laplace's equations are solved, supplemented by the appropriate boundary conditions and the limiting conduct at the exit of the nozzle. The theoretical approach matches the expected physics and captures the corresponding essential features in a fully three-dimensional fashion via the derivation of closed-form expressions for the related electrostatic fields as infinite series expansions of cylindrical harmonic eigenfunctions. The feasibility of our method for both cases of the described experimental setup is eventually demonstrated by efficiently incorporating the necessary numerical implementation of the obtained formulae. The analytical model is benchmarked against reported numerical results, whereas discrepancies are commented and prospective work is discussed.

Sanitary effect of FE-DBD cold plasma in ambient air on sewage biosolids.

Sewage sludge is treated by means of cold plasma and stabilization in terms of biological load deactivation is achieved. The plasma is produced by floating electrode dielectric barrier discharge operating with air under atmospheric pressure conditions. The process is presented in detail and the discharge is characterized electrically. Additionally, simulation of the thermal flow inside the process chamber is implemented, using computational fluid dynamics. Deactivation of the serotypes S. Paratyphi B., S. Livingstone, S. Mbandaka and S. Typhimurium, and Escherichia coli and Coliforms, is hereby claimed. The process involves mean electrical power in the range of tens of watts, treatment time in the scale of minutes, and maximum instantaneous temperature <400 K. The present work is a preliminary contribution towards the promotion of advanced methods for the pro-ecological management of biosolids, according to European Regulations.

Time and chemotherapy treatment trends in the treatment of elderly patients (age>or=70 years) with non-small cell lung cancer.

AIMS: Palliative chemotherapy in non-small cell lung cancer (NSCLC) has been established since 1995 and little chemotherapy treatment was given to these patients before 1990. This retrospective study investigates the treatment outcome of elderly patients (age>or=70 years) with NSCLC over the past 13 years in a large UK cancer centre. MATERIALS AND METHODS: A comparison of all-cause survival between the time periods 1990-1994, 1995-1999 and 2000-2004 was adjusted for age, gender, stage and performance status. A comparison of survival was also made between three age groups: 70-74, 75-79 and 80+ years. RESULTS: Between 1990 and 2004, 302 patients>or=70 years had NSCLC. There were differences in age and performance status between the time periods. There was no improvement in median survival between the three time periods (P=0.6). There was little difference in outcome between the three age cohorts. CONCLUSIONS: The analysis shows that there has been no significant improvement in survival for elderly patients with advanced lung cancer treated with chemotherapy in the past 13 years.

Circulating tissue inhibitor of matrix metalloproteinase-4 (TIMP-4) in systemic sclerosis patients with elevated pulmonary arterial pressure.

Decreased levels of matrix metalloproteinases (MMPs) or excess levels of their tissue inhibitors (TIMPs) may contribute to dysregulation of extracellular matrix turnover in systemic sclerosis (SSc). In a cross-sectional study of 106 SSc patients, we measured serum levels of TIMP-4 which is preferentially expressed in cardiovascular structures and searched for correlations with simultaneously performed echocardiography measurements of pulmonary artery systolic pressure (PASP), myocardial performance, and pulmonary function tests. TIMP-4, but not MMP-9, levels were significantly raised in patients with SSc than controls. However, in the subgroup of patients with PASP measurements lower to 40 mmHg (n = 69), TIMP-4 levels were comparable to controls irrespective of the presence of diffuse or limited skin involvement, or lung fibrosis. Individual PASP measurements suggestive of pulmonary hypertension were associated with increased TIMP-4 serum levels (P = .03), independently of age, extent of skin sclerosis, or lung fibrosis, suggesting a cardiopulmonary vasculature-specific role of TIMP-4 activation in SSc.

A national human neuroimaging collaboratory enabled by the Biomedical Informatics Research Network (BIRN).

The aggregation of imaging, clinical, and behavioral data from multiple independent institutions and researchers presents both a great opportunity for biomedical research as well as a formidable challenge. Many research groups have well-established data collection and analysis procedures, as well as data and metadata format requirements that are particular to that group. Moreover, the types of data and metadata collected are quite diverse, including image, physiological, and behavioral data, as well as descriptions of experimental design, and preprocessing and analysis methods. Each of these types of data utilizes a variety of software tools for collection, storage, and processing. Furthermore sites are reluctant to release control over the distribution and access to the data and the tools. To address these needs, the Biomedical Informatics Research Network (BIRN) has developed a federated and distributed infrastructure for the storage, retrieval, analysis, and documentation of biomedical imaging data. The infrastructure consists of distributed data collections hosted on dedicated storage and computational resources located at each participating site, a federated data management system and data integration environment, an Extensible Markup Language (XML) schema for data exchange, and analysis pipelines, designed to leverage both the distributed data management environment and the available grid computing resources.

Snapping knee syndrome in an athlete caused by the semitendinosus and gracilis tendons. A case report.

We report a case of symptomatic subluxation of the semitendinosus and gracilis over the posteromedial corner of the tibia manifesting with snapping. This is the first such case recorded in non-Asian population and in a high-demand athlete. Snapping was reproduced on active extension of the knee and at initiation of flexion and could be readily palpated over the posteromedial aspect of the tibia. Dynamic ultrasound, a key diagnostic tool in such conditions, revealed abrupt anterior subluxation of the semitendinosus and gracilis tendons during active terminal extension over the insertion of the semimembranosus as well as areas of tendinopathy corresponding with the site of subluxation. Due to failure of conservative treatment, surgery was undertaken, involving tenotomy and resection of a 10-12 cm segment of the semitendinosus and gracilis. The patient returned to the same level of sporting activities within 4 months and remained symptom-free 18 months post-operatively. The role of eccentric loading of the knee joint, as well as the "protective" role of the accessory tendinous bands and aponeurotic expansions of the semitendinosus and gracilis is discussed.

Point-shear wave elastography predicts liver hypertrophy after portal vein embolization and postoperative liver failure.

PURPOSE: To correlate point-shear wave elastography (SWE) with liver hypertrophy after right portal vein embolization (RPVE) and to determine its usefulness in predicting postoperative liver failure in patients undergoing partial liver resection. PATIENTS AND METHODS: Point-SWE was performed the day before RPVE in 56 patients (41 men) with a median age of 66 years. The percentage (%) of future remnant liver (FRL) volume increase was defined as: %FRLpost-%FRLpre%FRLpre×100 and assessed on computed tomography performed 4 weeks after RPVE. RESULTS: Median (range) %FRLpre and %FRLpost was respectively, 31.5% (12-48%) and 41% (23-61%) (P<0.001), with a median %FRL volume increase of 25.6% (-8; 123%). SWE correlated with %FRL volume increase (P=-0.510; P<0.001). SWV (P=0.003) and %FRLpre (P<0.001) were associated with %FRL volume increase at multivariate regression analysis. Forty-three patients (77%) were operated. Postoperative liver failure occurred in 14 patients (32.5%). Median SWE was different between the group with (1.68m/s) and without liver failure (1.07m/s) (P=0.018). The AUROC of SWE predicting liver failure was 0.724 with a best cut-off of 1.31m/s, corresponding to a sensitivity of 21%, specificity of 96%, positive predictive value 75% and negative predictive value of 72%. SWE was the single independent preoperative variable associated with liver failure. CONCLUSIONS: SWE assessed by point-SWE is a simple and useful tool to predict the FRL volume increase and postoperative liver failure in a population of patients with liver tumor.

The novel activation of ABL by fusion to an ets-related gene, TEL.

In human leukemia, activation of the ABL proto-oncogene locus on chromosome 9 most commonly occurs as a result of its fusion to the BCR locus on chromosome 22. The resulting chimeric protein displays an elevated tyrosine kinase activity. We have identified a novel activation of ABL which involves a gene located on chromosome 12, designated TEL. Like BCR, TEL is fused in-frame with ABL and produces a fusion protein with an elevated tyrosine kinase activity when assayed in an immune complex. The amino-terminal sequences of TEL encode a helix-loop-helix motif which may mediate dimerization.

Nucleotide sequence of the dihydrofolate reductase gene of methotrexate-resistant Lactobacillus casei.

The nucleotide sequence of the dihydrofolate reductase (DHFR) gene of a methotrexate-resistant strain of Lactobacillus casei, which is the source of DHFR for nuclear magnetic resonance (NMR) studies, has been determined. The derived amino acid sequence differs from that obtained by protein sequencing by the presence of aspartic acid instead of asparagine at position 8 and proline instead of leucine at position 90. The nucleotide sequences of 320-bp 5' and 335-bp 3' flanking regions of this gene have also been determined.

Classical information and distillable entanglement

We establish a quantitative connection between the amount of lost classical information about a quantum state and the concomitant loss of entanglement. Using methods that have been developed for the optimal purification of mixed states, we find a class of mixed states with known distillable entanglement. These results can be used to determine the quantum capacity of a quantum channel which randomizes the order of transmitted signals.

The effect of medial meniscectomy on strain distribution in the proximal part of the tibia.

The tibiae of five fresh adult human cadaver legs (amputated proximal to the knee) were instrumented with twenty-five strain-gauge rosettes and were tested in axial compression, simulating single-limb stance, at loads of as much as 2450 newtons. We compared the status of the normal knee, with menisci intact, with the status of the same knee after partial or total medial meniscectomy. The resultant changes in strain on the cortical bone of the tibia indicated that medial meniscectomy caused reduced compressive strains on the whole of the lateral aspect of the tibia, while on the medial aspect compressive strains were increased at all levels beyond seventy millimeters distal to the joint-line; however, within fifty millimeters of the joint-line on the medial aspect, there was a significant reduction of compressive strains.