Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Novel Technique for Securing Data Communication Systems by Using Cryptography and Steganography

The information security becoming more important and attracting much attention nowadays as the number of data being exchanged over the internet increased. There are various techniques to secure data communication, but the well-known and widely used techniques are cryptography and steganography. Cryptography changes the form of data in another form that is unreadable by anyone except the intended receiver. Steganography hide the existence of the secret data in other cover media so no one can detect the hidden data except the authorized receiver. In this paper, we proposed a new technique for securing the data communication systems by combining cryptography and steganography techniques. The cryptography algorithm that was used in this paper is Modified Jamal Encryption Algorithm (MJEA); it is a symmetric (64-bit) block encryption algorithm with (120-bit) key. For steganography we designed an enhanced form of Least Significant Bit (LSB) algorithm with (128-bit) Steg-Key. The performance of the proposed technique has been evaluated by considering several experimental tests such as impressibility test, embedding capacity test and security test. For this purpose, the proposed technique was applied on several 24-bit colored PNG cover images. Different simulation metrics adopted in the evaluation process such as Peak Signal to Noise Ratio (PSNR), Mean Square Error (MSE), the payload embedding capacity and the histogram distribution analysis. Furthermore, an image quality comparison between the proposed technique and other LSB algorithms similar to our work has been conducted. All experimental results proved the strength of the proposed algorithm in securing the transition of data over unsecure channel to protect it against any attack. Furthermore, the simulation results show the superiority of our proposed algorithm when compared with other algorithms in terms of PSNR and embedding capacity

PP 11-13 and Health Professions, King Saud Bin Abdulaziz University for Health sciences, Ministry of National Guard Health Affairs, Mail Code (3124), PO Box 3660

Abstract: In this article we present our results on a study of performance gap among our male and female college students. Our choice for the study tool for this work was the force concept inventory (FCI). We gave the test to our students twice; before and after our instructions on force and motion. The overall performance of male and female students in both tests along with details about individual questions is reported. The mean percentage scores showed a gender gap in favor of male students. Male students outperformed female students in almost every one of the thirty questions of the inventory in both the pre and the post test

Diffusion and conversion dynamics for neutral muonium in aluminum nitride

Muon spin depolarization rates and hyperfine decoupling curves imply the existence of a neutral muonium center to high temperatures in AlN, providing an experimental model for interstitial atomic hydrogen. This center has a hyperfine interaction close to that of the free atom, but with a small temperature-dependent dipolar contribution indicating weak anisotropy. We discuss the site assignment and present results on the diffusion of these centers in AlN and associated conversion rates obtained from the depolarization data. Low-temperature motion is due to tunneling while thermally activated processes dominate at high temperatures. Diffusion-limited conversion out of the mobile atomic state is observed in both regimes

Investigating the Knowledge of Vector Concepts of First Year Medical Students

Purpose: We report in this article the results of a study conducted on our first year medical students. This study is supposed to serve as an initial general survey of students' knowledge of vector concepts. Our goal here is to get initial insights on students’ misconceptions when about vectors. The results from this study should help plan our next stage of this particular research project. Method: Our test tool was the test of understanding vectors “TUV” first developed by Pablo Barniol and Genaro Zavala in 2014.1 The test was given to a total of 240 students at the beginning of the semester before they were exposed to any vector related instruction (pre-test). Results: We found weak overall performance of our students represented in very low scores in the test (average score 26%). We were also able to determine the major misconceptions held by students by examining their wrong answers for each question. Some of the misconceptions found were: using tip-to-tip method rather than tail-to-tip to add or subtract vectors, the component of a vector (x or y) has a magnitude equal to the vector magnitude, and multiplying a vector with a negative sign doesn't change its direction. Full list of vectors misconceptions is reported in the discussion. Discussion: Results reveal some serious problems in vector concepts understanding that require some attention and careful future planning. Based on the results, we recommended adding a special section on vector concepts to be given to students right at the start of the semester to prepare them better for the course

Anisotropic muonium centers in aluminum nitride

An atomic-like neutral muonium center with a small anisotropy is inferred from hyperfine decoupling curves and longitudinal relaxation data on AIN. The isotropic contribution of A = 4422 M Hz, 99% of the full vacuum value, is accompanied by a weak dipolar term with D = 144 MHz as average values extracted from complete decoupling curves at a few temperatures. Simulations assuming the four nitrogen antibonding sites well reproduce the decoupling data. The hyperfine constants are consistent with those previously obtained from fitting temperature-dependent longitudinal relaxation rates to a simple model for Mu(0) motion. (c) 2005 Elsevier B.V. All rights reserved

Muonium states and dynamics in 4H and 6H silicon carbide

Two isotropic Mu(0) centers are found in 4H Silicon Carbide (SiC) and a total of four Mu(0) states are seen in the 6H-SiC polytype. We report the temperature dependence of hyperfine constants, signal amplitudes, and relaxation rates for three Mu(0) centers in p-type 6H-SiC from spin precession data at 6T. Low-field results for the diamagnetic fraction imply two ionization steps with energies of 0.21 and 0.88 eV. Additional dynamics seen in several different SiC samples are discussed; however, specific assignments of site or charge-state transitions are not yet certain. (c) 2005 Elsevier B.V. All rights reserved

Motion of Mu(+) in Transparent Conducting Oxides

We have been investigating diamagnetic muonium centers in several optically transparent conducting oxides by zero field (ZF) muon spin depolarization. In this report we present our findings on single crystal beta - Ga2O3. ZF data from Ga2O3 are represented with a single static Kubo Toyabe (sKT) function over the whole scanned temperature range. Below room temperature we confirm shallow donor ionization. Between 400 and 500 K, sKT relaxation rates indicate local motion for Mu(+) among a set of similar sites. Above 500 K the relaxation rate decreases and reaches a plateau staying roughly constant up to 650 K. This behaviour is consistent with Mu(+) finding an energetically more favorable site with a smaller local dipolar field. Above 650K the depolarization rate starts to decrease again. We attribute this behavior to the onset of global Mu(+) diffusion. We have performed transverse field muon spin rotation experiments at low temperatures to investigate Mu(0) ionization. We will discuss the general trend of Mu(+) behavior and possibility of a second shallow Mu donor

Motion of positively charged muonium in ZnO

We report on a study of the motional characteristics of positively charged muonium defect centers in ZnO as an analog for H+ behavior. Muon spin depolarization measurements at zero applied magnetic field were completed from 20 K to 400 K, with preliminary results to 750 K. Results at the lower temperatures imply that Mu(+) occupied two sites, and indicate local motion as thermally assisted tunneling with a characteristic energy of similar to 60 meV, as well as a site change transition above 200 K with barrier energy similar to 440 meV. Based on theoretical results, we have tentatively assigned these features to tunneling among three equivalent oxygen anti-bonding sites (AB(perpendicular to)) and a transition to a lower-energy bond-centered site (BC parallel to) oriented along the c-axis. Preliminary fits suggest that global diffusion of muonium occurs above 400 K, with a diffusion barrier energy of similar to 0.7 eV. Published by Elsevier B.V

Muonium dynamics in transparent conducting oxides

The motional and electrical properties of positively charged muonium (Mu(+)) centers in single crystal beta-Ga2O3 are investigated via zero field muon spin relaxation (ZF-MuSR). Below room temperature we find two distinct shallow muonium centers with ionization energies of 7 and 16 meV. Above room temperature, at least three different Mu(+) signals are resolved; two of these are metastable while the third shows characteristics of a stable ground state. As the temperature is elevated, metastable centers undergo several transitions. We obtain the relevant barrier energies associated with these site-change transitions. By 700 K, most muons occupy the mobile ground state, and an activation energy of about 1.65 eV is inferred for Mu(+) diffusion from the hop rates obtained for this state. (C) 2011 Elsevier B.V. All rights reserved