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Introduction The bifrontal transbasal approach is an anterior midline skull base approach to anterior skull base, sellae region and, if needed, to posterior skull base in the midline, often used for tumoral lesions but also useful for vascular or infectious pathologies. Methods Descriptive anatomic study, 5 formalin-fixed human cadaveric heads were used injected with colored silicone. The dissection was made step-by-step to describe every anatomic structure encountered. The working distance was obtained from the posterior wall of the frontal sinus with and without orbital rim to the pituitary stalk, the sellae, the pontomedullary sulcus, and the anterior margin of the foramen magnum. Results Stepwise anatomic dissection was performed dividing the surgical technique into 6 stages: soft-tissue stage, bone stage, sinus stage, clival stage, intradural, and measurements. The objective of making the supraorbital osteotomy was to improve the vision over the neural structures without brain retraction and limited to the midline supraorbital rim to avoid aggressive manipulation and injury to the orbit. The working distances measured with the orbital rim were on average: to the pituitary stalk, 70.5 mm; to the sellae, 81.3 mm; to the pontomedullary sulcus, 97 mm; and the foramen magnum, 99.5 mm. Without the orbital rim measures were: to the pituitary stalk, 57 mm; to the sellae, 62.5 mm; to the pontomedullary sulcus, 96 mm; and the foramen magnum, 98.5 mm. Conclusions The addition of osteotomies including removing of the orbital rim improves the access to the central skull base with special benefits on the working distances to the sellae region.

Worldwide population is in permanent growth, leading to an over-presser on the food resources. This demand leads to an over-exploitation of land and water resources. Recently, the quinoa plant has attracted attention as alternative crop with high nutritive value and high tolerance to the marginal conditions. In this study, a field experiment was conducted during two successive seasons to investigate the effect of deficit irrigation on the agronomic performance. Four treatments of deficit irrigation (100%, 50%, 33% ETc and rainfed) were applied to one variety in the first season and to four genotypes (two varieties and two lines). The results were evaluated by measuring biomass and seed quinoa yield, water-use efficiency, harvest index, seed size and 1000 seeds weight. Results show that the implementation of deficit irrigation is an appropriate strategy to reduce the use of agricultural water and maintain relatively high yields. On the other hand, the results of the economic quality reflected by the size and weight of seed yield, indicates that quinoa can be considered a well-adapted to the conditions of water scarcity culture. According to agronomic parameters, L143 line followed by the line L11 showed a high potential of adaptation under the different treatments of stress, while the “Puno” variety presented the best performance under the favorable conditions of irrigation (100% ETc). info:eu-repo/semantics/publishedVersion

Background Both drug‐coated balloon (DCB) angioplasty and conventional plain balloon angioplasty (PBA) can be implemented to treat hemodialysis dysfunction. The present study aims to compare the safety and efficacy of these 2 approaches by conducting a meta‐analysis of available randomized controlled trials. Methods and Results PubMed, Cochrane Library, and Embase databases were queried from establishment to January 2021. A total of 18 randomized controlled trials including 877 and 875 patients in the DCB and PBA groups, respectively, were included in the present meta‐analysis. Target lesion primary patency, circuit patency, target lesion revascularization, and mortality were pooled. Odds ratios (ORs) were reported with 95% CIs. Publication bias was analyzed with funnel plot and Egger test. Target lesion primary patency was higher among patients who underwent DCB (OR, 2.93 [95% CI, 2.13–4.03], P P P P =0.005]). Compared with the PBA group, the DCB group had lower odds of target lesion revascularization during follow‐up (OR, 0.43 [95% CI, 0.23–0.82], P =0.001 at 6 months; OR, 0.74 [95% CI, 0.32–1.73], P =0.490 at 1 year). The OR of mortality was comparable between 2 groups at 6 months (OR, 1.18; 95% CI, 0.42–3.33 [ P =0.760]) and 1 year (OR, 0.93; 95% CI, 0.58–1.48 [ P =0.750]). Conclusions Based on evidence from 18 randomized controlled trials, DCB angioplasty is superior to PBA in maintaining target lesion primary patency and circuit patency among patients with dialysis circuit stenosis. DCB angioplasty also reduces target lesion revascularization with a similar risk of mortality compared with PBA.

Objective To analyze the three-dimensional relationships of the operculoinsular compartments, using standard hemispheric and white matter fiber dissection and review the anatomy of association fibers related to the operculoinsular compartments of the Sylvian fissure and the main white matter tracts located deep into the insula. The secondary aim of this study was to improve the knowledge on this complex region to safely address tumor, vascular, and epilepsy lesions with an integrated perspective of the topographic and white matter fiber anatomy using 2D and 3D photographs. Methods Six cadaveric hemispheres were dissected. Two were fixed with formalin and the arteries were injected with red latex dye; the remaining four were prepared using the Kingler method and white fiber dissections were performed. Results The insula is located entirely inside the Sylvian fissure. The topographic hemispheric anatomy, Sylvian fissure, opercula, surrounding sulci and gyri, as well as the M2, M3, and M4 segments were identified. The anatomy of the insula, with the sulci and gyri and the limiting sulci, were also identified and described. The main white matter fiber tracts of the operculoinsular compartments of the Sylvian fissure as well as the main association and commissural fibers located deep in the insula were dissected and demonstrated. Conclusions Complementing topographic anatomy with detailed study of white matter fibers and their integration can help the neurosurgeon to safely approach lesions in the insular region, improving postoperative results in the microsurgical treatment of aneurysmal lesions, insular tumors, or epilepsy surgery.

This paper is the continuation of a research carried out by Alabish et.al, which depicts the scattering objects effects on a blocked indoor wireless 5G link by a human body using a simple approach. Some measurement were made on the scattering effects due to having an object close to the link in this case it is a human body. In this paper, more measurements were conducted at 32 GHz. The double knife-edge diffraction (DKED) model was used in order to foresee the attenuation due to human body. To test the prediction precision of the model, simulation was then compared with measurements. The obtained results indicate that the assumed simple models for the indoor links performed well.

We describe the Kottamia Faint Imaging Spectro-Polarimeter (KFISP) that has been recently developed and designed to be mounted to the Cassegrain focus of the 1.88m telescope at Kottamia Astronomical Observatory (KAO), Egypt. The optical design of KFISP is developed such that it can be used in various modes of operation. These are: direct imaging, spectroscopic (low and medium resolution), polarimetric imaging, and spectro-polarimetric. The KFISP is an all-refractive design to meet the polarimetric requirements and includes a focal reducer with a corrector section, collimator section, parallel beam section (containing various imaging components), and camera section. The corrector section gives an unvignetted Field-of-View (FoV) of 8ʹ × 8ʹ and the collimator section has a focal length of 305 mm and matches the focal ratio of the input beam. The parallel beam section is 200 mm long and near the middle of it there is an image of the telescope pupil. The camera section includes 5 elements and has a focal length of 154.51 mm which gives an instrument effective final focal ratio of f/6.14 (acting as a telescope focal reducer of 1:2 ratio). The KFISP contains an internal calibration system which hosts the calibration light injection system, an integrating sphere equipped with the required calibration light sources. The opto-mechanical parts of KFISP contain double-layered carbon fiber strut structure and comprises its subsystems of slit and guider assemblies, filter wheel drawer, grism wheel drawer, polarimetric components cubical box, and CCD camera which is integrated with camera optics. The KFISP has been fully commissioned, mounted and is being tested in all modes of operation. In this paper we introduce the ambitious scientific goals, the optical setups of KFISP, its opto-mechanical implementation and the performance analysis of the instrument. In addition, we will present sample of the first light observations obtained from the instrument.

Introduction Reporting Medication Errors (MEs) is a critical issue that confronts healthcare providers and institutions all over the world, yet this issue has only recently been examined in developing countries. Purpose To explore the perceptions of Jordanian nurses around reporting MEs and to identify potential barriers to reportage in their context. Methodology A qualitative descriptive approach was followed; whereby24 Jordanian nurses were interviewed. Results Two main themes emerged. The first revolved around nurses' perceptions of ME reporting, and the second theme pertained to the daily barriers that prevented them from reporting MEs. Conclusion This study identified many individual behaviors and system defects that exacerbate the lack of ME reporting in Jordan. The results point to an opportunity for Jordanian hospital managers to acknowledge these problems and thereby facilitate their resolution and increase the quality of healthcare in their organizations.

Purpose To develop and validate a multiparameterized artificial neural network (ANN) on the basis of personal health information for prostate cancer risk prediction and stratification. Methods The 1997 to 2015 National Health Interview Survey adult survey data were used to train and validate a multiparameterized ANN, with parameters including age, body mass index, diabetes status, smoking status, emphysema, asthma, race, ethnicity, hypertension, heart disease, exercise habits, and history of stroke. We developed a training set of patients ≥ 45 years of age with a first primary prostate cancer diagnosed within 4 years of the survey. After training, the sensitivity and specificity were obtained as functions of the cutoff values of the continuous output of the ANN. We also evaluated the ANN with the 2016 data set for cancer risk stratification. Results We identified 1,672 patients with prostate cancer and 100,033 respondents without cancer in the 1997 to 2015 data sets. The training set had a sensitivity of 21.5% (95% CI, 19.2% to 23.9%), specificity of 91% (95% CI, 90.8% to 91.2%), area under the curve of 0.73 (95% CI, 0.71 to 0.75), and positive predictive value of 28.5% (95% CI, 25.5% to 31.5%). The validation set had a sensitivity of 23.2% (95% CI, 19.5% to 26.9%), specificity of 89.4% (95% CI, 89% to 89.7%), area under the curve of 0.72 (95% CI, 0.70 to 0.75), and positive predictive value of 26.5% (95% CI, 22.4% to 30.6%). For the 2016 data set, the ANN classified all 13,031 patients into low-, medium-, and high-risk subgroups and identified 5% of the cancer population as high risk. Conclusion A multiparameterized ANN that is based on personal health information could be used for prostate cancer risk prediction with high specificity and low sensitivity. The ANN can further stratify the population into three subgroups that may be helpful in refining prescreening estimates of cancer risk.

Several studies have linked codeletion of chromosome arms 1p/19q in low-grade gliomas (LGG) with positive response to treatment and longer progression-free survival. Hence, predicting 1p/19q status is crucial for effective treatment planning of LGG. In this study, we predict the 1p/19q status from MR images using convolutional neural networks (CNN), which could be a non-invasive alternative to surgical biopsy and histopathological analysis. Our method consists of three main steps: image registration, tumor segmentation, and classification of 1p/19q status using CNN. We included a total of 159 LGG with 3 image slices each who had biopsy-proven 1p/19q status (57 non-deleted and 102 codeleted) and preoperative postcontrast-T1 (T1C) and T2 images. We divided our data into training, validation, and test sets. The training data was balanced for equal class probability and was then augmented with iterations of random translational shift, rotation, and horizontal and vertical flips to increase the size of the training set. We shuffled and augmented the training data to counter overfitting in each epoch. Finally, we evaluated several configurations of a multi-scale CNN architecture until training and validation accuracies became consistent. The results of the best performing configuration on the unseen test set were 93.3% (sensitivity), 82.22% (specificity), and 87.7% (accuracy). Multi-scale CNN with their self-learning capability provides promising results for predicting 1p/19q status non-invasively based on T1C and T2 images. Predicting 1p/19q status non-invasively from MR images would allow selecting effective treatment strategies for LGG patients without the need for surgical biopsy.

Objective The objective of this study was to compare transcortical and posterior interhemispheric approaches to the atrium using a combined approach of white matter fiber dissections and magnetic resonance (MR) tractography. Methods Ten cerebral hemispheres were examined and dissected from the lateral-to-medial surface and from the medial-to-lateral surface, with special attention to the white matter tracts related to the atrium. MR tractography was used to show the relationship of three-dimensional white matter fibers with the atrium of the lateral ventricle and to compare with cadaveric dissection results. Results The atrium was related laterally to the superior longitudinal fasciculus II and III, middle longitudinal fasciculus, arcuate fasciculus, vertical occipital fasciculus, and sagittal stratum. Medially, it is related to the superior longitudinal fasciculus I, cingulum, sledge runner, and forceps major. Conclusions A combined approach of cadaveric white matter fiber dissections and MR tractography were used to describe the main white matter tracts related to the posterior interhemispheric approach and the transcortical approach, providing an in-depth understanding of the three-dimensional anatomy of white matter fibers and the atrium. In the present study, among approaches examined, the posterior interhemispheric parasplenial transprecuneus approach placed fewer eloquent tracts at risk; however, traversing the sledge runner and the forceps major is unavoidable by this approach.

Background: Cerebellar mutism (CM) is defined as the lack of speech production, despite an intact state of consciousness and cognitive function, that happens secondary to a cerebellar insult. To the best of our knowledge, only five cases have thus far been described in the English literature. In this paper, we report the sixth incidence overall, which is also the first case of a CM associated with penetrating head injury. The relevant literature is reviewed and analyzed, our current knowledge of the neuroanatomical and functional relations is summarized, and potential future research endeavors are indicated. Case Description: An 8-year-old girl was transferred to our hospital having had fallen on a rod that penetrated her neck behind the ear. An urgent computed tomography scan of the head revealed a right cerebellar contusion with surrounding edema. Three days later, she became mute but was still obeying commands. Repeat imaging showed a resolving cerebellar contusion with increased edema and mass effect. By day 9, she had uttered a few words. At 1-month follow-up, the child had regained normal speech. Conclusion: Posttraumatic CM is a rare and probably underreported condition with only six documented cases to date. Although it may well be on the same spectrum as postoperative CM, further understanding of the exact mechanism, clinical course, and prognosis of this entity is bound to significantly improve the recovery and quality of life of head trauma patients.

Background and Objective: Artemisinin-based combination therapies are the first-line antimalarial drugs used to treat uncomplicated Plasmodium falciparum malaria in many endemic countries worldwide. This study was conducted to assess the efficacy and tolerability of two fixed-dose formulations of artesunate-amodiaquine and artemether-lumefantrine for the treatment of Plasmodium falciparum malaria in Chad. Methodology and Results: A two-arm single cohort study was conducted assessing the efficacy artesunate-amodiaquine and artemether-lumefantrine for the treatment of children with uncomplicated falciparum malaria. This study was carried out from December 14, 2019 to March 14, 2020 at the Massakory I Health Center in Chad. Primary efficacy endpoint was day 28, parasitological cure rate. Secondary endpoints were parasite and fever clearance times and tolerability. A total of 113 patients were included, including 56 in the artesunate-amodiaquine arm and 57 in the artemether-lumefantrine arm. In intention to treat these patients, the Adequate Clinical and Parasitological Response on day 28 were 100% for the two groups. No early treatment failure was observed. The drugs were well tolerated and no serious adverse events were noted. Conclusion: Both forms of Artemisinin-based combination therapy were still effective and safe in the treatment of uncomplicated P. falciparum malaria in Chad. Further studies are warranted in different regions of Chad for monitoring of drug resistance.

Colorectal cancer (CRC) is third in prevalence and mortality among all cancers in the US. Currently, the United States Preventative Services Task Force (USPSTF) recommends anyone ages 50-75 and/or with a family history to be screened for CRC. To improve screening specificity and sensitivity, we have built an artificial neural network (ANN) trained on 12 to 14 categories of personal health data from the National Health Interview Survey (NHIS). Years 1997-2016 of the NHIS contain 583,770 respondents who had never received a diagnosis of any cancer and 1409 who had received a diagnosis of CRC within 4 years of taking the survey. The trained ANN has sensitivity of 0.57 ± 0.03, specificity of 0.89 ± 0.02, positive predictive value of 0.0075 ± 0.0003, negative predictive value of 0.999 ± 0.001, and concordance of 0.80 ± 0.05 per the guidelines of Transparent Reporting of Multivariable Prediction Model for Individual Prognosis or Diagnosis (TRIPOD) level 2a, comparable to current risk-scoring methods. To demonstrate clinical applicability, both USPSTF guidelines and the trained ANN are used to stratify respondents to the 2017 NHIS into low-, medium- and high-risk categories (TRIPOD levels 4 and 2b, respectively). The number of CRC respondents misclassified as low risk is decreased from 35% by screening guidelines to 5% by ANN (in 60 cases). The number of non-CRC respondents misclassified as high risk is decreased from 53% by screening guidelines to 6% by ANN (in 25,457 cases). Our results demonstrate a robustly-tested method of stratifying CRC risk that is non-invasive, cost-effective, and easy to implement publicly.

Lung cancer is the most common cause of cancer-related death globally. As a preventive measure, the United States Preventive Services Task Force (USPSTF) recommends annual screening of high risk individuals with low-dose computed tomography (CT). The resulting volume of CT scans from millions of people will pose a significant challenge for radiologists to interpret. To fill this gap, computer-aided detection (CAD) algorithms may prove to be the most promising solution. A crucial first step in the analysis of lung cancer screening results using CAD is the detection of pulmonary nodules, which may represent early-stage lung cancer. The objective of this work is to develop and validate a reinforcement learning model based on deep artificial neural networks for early detection of lung nodules in thoracic CT images. Inspired by the AlphaGo system, our deep learning algorithm takes a raw CT image as input and views it as a collection of states, and output a classification of whether a nodule is present or not. The dataset used to train our model is the LIDC/IDRI database hosted by the lung nodule analysis (LUNA) challenge. In total, there are 888 CT scans with annotations based on agreement from at least three out of four radiologists. As a result, there are 590 individuals having one or more nodules, and 298 having none. Our training results yielded an overall accuracy of 99.1% [sensitivity 99.2%, specificity 99.1%, positive predictive value (PPV) 99.1%, negative predictive value (NPV) 99.2%]. In our test, the results yielded an overall accuracy of 64.4% (sensitivity 58.9%, specificity 55.3%, PPV 54.2%, and NPV 60.0%). These early results show promise in solving the major issue of false positives in CT screening of lung nodules, and may help to save unnecessary follow-up tests and expenditures.

Schizophrenia has been proposed to result from impairment of functional connectivity. We aimed to use machine learning to distinguish schizophrenic subjects from normal controls using a publicly available functional MRI (fMRI) data set. Global and local parameters of functional connectivity were extracted for classification. We found decreased global and local network connectivity in subjects with schizophrenia, particularly in the anterior right cingulate cortex, the superior right temporal region, and the inferior left parietal region as compared to healthy subjects. Using support vector machine and 10-fold cross-validation, nine features reached 92.1% prediction accuracy, respectively. Our results suggest that there are significant differences between control and schizophrenic subjects based on regional brain activity detected with fMRI.

Aims Primary care management of diabetes was examined using the Caribbean Health Research Council (CHRC) guidelines. Methods We retrospectively examined a cross-section of 646 type 2 people with diabetics over 12 months with 1st visit between 1997 and 2005. Results There were more women (65.8%) than men (34.2%) with age range between 29 and 89 years. Blood pressure and weight were evaluated in >95% of patients at each centre. Waist circumference and BMI were not measured at any time and HbA 1 c was infrequently measured (1.6–7%) over the 12 months. Information on family history (87.5%), smoking and alcohol (78.1%), exercise (21.4%), socioeconomic status (19.4%) and education (0.3%), and fasting blood sugar (97.2%), lipid profile (51.8%) and serum creatinine (37.9%) were assessed at the 1st visit. At follow-up patients were advised on treatment compliance (47.2%), diet (34.2%), exercise (18.5%) and rarely on home monitoring of blood glucose (0.3%). Peripheral sensations, pedal pulses (6%), visual acuity (3.3%), fundoscopy (12.1%) and ECG (3.9%) were scarcely examined at the annual visit. Conclusions Current management of diabetes in primary care in Trinidad falls short of Caribbean guideline recommendations. The CHRC and Ministry of Health should jointly educate caregivers of diabetes to implement the guidelines, with annual audits to identify shortfalls in management.

Radiochromic film (RCF) has been shown to be a precise and accurate secondary planar dosimeter for acute exposure radiation fields. However, its application to low dose-rate brachytherapy has been questioned because of possible dose-rate effects. To address this concern, we have measured the optical density (OD) of Model 55-2 RCF as a function of time (interval between the completion of irradiation and densitometry using a 633 nm laser scanner) following exposure (from less than 1 hour to 90 days) for single and split doses from 1 Gy to 100 Gy. Our work demonstrates that film darkening as a function of post-irradiation time depends significantly on total dose, with films exposed to lower doses developing faster than films given higher doses. At 1 Gy, the OD 90 days after exposure is 200% larger than that measured 1 h after exposure compared to a 20% increase over 90 days for doses larger than 20 Gy. An empirical model with time-independent, fast and slow growth terms was used to fit single exposure data. The dependence of the resulting best-fit parameters on dose was investigated. Splitting the dose into two fractions (20 Gy followed by doses of 1-80 Gy 24 h later) results in modest post-irradiation time-dependent changes in the total optical density (at most 15% at small doses), which dissipates within 20 hours following the second exposure. This experimental finding is consistent with the predictions of a simple cumulative dose superposition model. Overall, both experimental and empirical modeling suggest that dose-rate effects may be relatively small despite the strong dependence of film darkening kinetics on total dose. However, more experimental evaluation of radiochromic film response dependence on dose rate and dose-time-fractionation patterns is needed.

International audience; Proteins are separated in field flow fractionation (FFF) according to a well-established mechanism described as the “Normal or Brownian” mode. In the case of the sub-technique using a hollow fiber, the focalization/relaxation position can be observed visually only with a transparent holder and using dyes as samples. Whatever the choice of instrumentation, a dye-free method is proposed to determine the center of the zone from experimental fractograms by means of only two sample elutions. It is also possible to determine and model the kinematics of the sample toward the equilibrium focalization/relaxation position as well as the real dimensions of the fiber during the separation process.

Purpose: To test the amorphous silicon (aSi) electronic portal imaging device(EPID) for quality assurance (QA) of the multi‐leaf collimators(MLC) and to validate its use as a dynamic intensity‐modulated radiation therapy(IMRT) QA device. Method and Materials: Established MLC QA for IMRT utilizes dosimetric outputs from a single point in phantom with a chamber, and radiographic film to capture the density‐pattern of the MLC. We propose using the aSi EPID 2D‐density distribution to replace the chamber/film for MLC QA, and to verify the dosimetry and mechanics of the MLC for IMRT. A protocol was developed to acquire QA data from the aSi EPID to provide tests for high dose gradients, average output doses, mechanical leaf stability, speed and positioning. The effects of various EPID exposed areas (2×2, 4×4, 6×6 cm2) were used for intercomparison measurements with ion chamber and film. Results:Radiographic film output at gantry angle 270° relative to 0° varies by less than 2%, while the film measurements at other gantry/collimator angles agree within 1% with the ionization chamber. For the same conditions, EPID outputs vary by 1%–5% depending upon exposed area. Output variations may be due to mechanical shifts, gantry and EPID sag, or MLC drifts due to gravity. Minimizing these effects is under further investigation. Conclusion: A method has been developed to utilize the aSi EPID for MLC QA. The 2D density distributions of the EPID offer the potential for more quantitative analysis, and this procedure can be integrated into a routine program for comprehensive dynamic MLC‐based IMRT and EPID QA. Conflict of Interest: This work supported in‐part by Varian Medical Systems.