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Machine translation for low-resource languages poses significant challenges, primarily due to the limited availability of data. In recent years, unsupervised learning has emerged as a promising approach to overcome this issue by aiming to learn translations between languages without depending on parallel data. A wide range of methods have been proposed in the literature to address this complex problem. This paper presents an in-depth investigation of semi-supervised neural machine translation specifically focusing on translating Arabic dialects, particularly Egyptian, to Modern Standard Arabic. The study employs two distinct datasets: one parallel dataset containing aligned sentences in both dialects, and a monolingual dataset where the source dialect is not directly connected to the target language in the training data. Three different translation systems are explored in this study. The first is an attention-based sequence-to-sequence model that benefits from the shared vocabulary between the Egyptian dialect and Modern Arabic to learn word embeddings. The second is an unsupervised transformer model that depends solely on monolingual data, without any parallel data. The third system starts with the parallel dataset for an initial supervised learning phase and then incorporates the monolingual data during the training process.

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STUDY DESIGN: Retrospective radiographic study. PURPOSE: We hypothesized that the pedicle is almost perpendicular to the interlaminar line in the sagittal plane of the lumbar vertebrae. The current study aimed to define the lumbar lamina-pedicle inclination to verify the right-angle concept and to estimate the safety zones of sagittal inclination during pedicle screw insertion. To the best of our knowledge there are no previous similar studies. OVERVIEW OF LITERATURE: Based on our observations in different spinal disorders including deformities, we noted that following a sagittal (cranial-caudal) trajectory perpendicular to the interlaminar line joining the two adjacent vertebrae would work well in most of the vertebral levels. METHODS: This was a retrospective study on normal lumbar spine lateral radiographs of patients who presented with low back pain and were reviewed by two observers. Different inclination angles were constructed to estimate the safety zones of the pedicle screws' sagittal inclination. RESULTS: Radiographs of 30 consecutive patients, 25 females and five males, with a mean age of 39.43±11.18 years, were studied. The mean angle of the interlaminar line and the pedicle axis was almost orthogonal at all the levels, with a range of 89.16°-94.63°, which was not affected by the lumbar sagittal profile. The safety zones of the pedicle screws were measured, and they revealed a safe sagittal range of 19.73°-24.40° if the screw was inserted from the pedicle axis, 21.03°-22.59° if inserted from the most cephalic part, and 13.31°-17.03° if inserted from the most caudal part. CONCLUSIONS: Our results confirmed the perpendicularity of the interlaminar line with the pedicle axis in the lumbar spine at all the levels. The interlaminar line is a useful guide for pedicle screw sagittal inclination.

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STUDY DESIGN: Retrospective radiographic study. PURPOSE: The hypothesis of this study was that the pedicle axis (PA) is almost perpendicular to the interlaminar line (ILL) in the sagittal plane of the thoracic vertebrae. The objective of the current study was to define the thoracic lamina-PA inclination in order to verify the right-angle concept and to estimate the safety zones for sagittal inclination during pedicle screw insertion. The authors, to the best of their knowledge, are unaware of previous similar studies. OVERVIEW OF LITERATURE: Based on the study's observations of different spinal disorders, including deformities, it was noted that following a sagittal cranial-caudal trajectory perpendicular to the ILL and joining the two adjacent thoracic vertebrae would work well at most vertebral levels. METHODS: This was a retrospective study on the computed tomography (CT) chest scans of patients with no spinal pathologies. The ILL-PA, superior and inferior safe angles of the pedicle screw trajectories, and the exit zone of the screw perpendicular to the ILL were reviewed by two observers via three-dimensional multiplanar reconstruction mode of the Horos DICOM software (https://horosproject.org/). RESULTS: The CT chest images of 30 consecutive patients (20 males and 10 females) with a mean age of 49.87±15.48 years (range, 24-74 years) were evaluated. The mean ILL-PA angle was almost orthogonal for all levels. This angle ranged between 86.21°±3.01° at D5 and 90.59°±2.72° at D10. The safety zones of the sagittal inclination of the pedicle screws were demonstrated. The results revealed that the least safe angle was when the screw was directed cranially along the middle part of the pedicle between 4.43°±0.75° at D8 and 6.94°±1.19° at D11. CONCLUSIONS: The results of this study confirmed the ILL-PA angle perpendicularity in the thoracic spine at all levels. The ILL is a useful guide for pedicle screw sagittal inclination.

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Background. This prospective randomized study compares the incidence of silent deep venous thrombosis (DVT) among 2 groups of patients who underwent laparoscopic bariatric surgery. The first group received mechanical thromboprophylaxis only, while the second group received a combination of mechanical and chemical thromboprophylaxis. Methods. This study included 150 morbidly obese patients who underwent primary one-stage laparoscopic bariatric surgery (sleeve gastrectomy and mini-gastric bypass) over a 6-month period. Patients were randomly assigned to 2 groups: group A (n = 75) was subjected to mechanical thromboprophylaxis in the form of perioperative elastic stockings on both lower limbs and early postoperative ambulation, and group B (n = 75) was subjected to combined mechanical thromboprophylaxis and chemical thromboprophylaxis in the form of 40 mg subcutaneous enoxaparin 12 hours before surgery and postoperative enoxaparin (40 mg subcutaneous every 24 hours) for 2 weeks. Bilateral lower limb venous duplex was done for all patients before discharge, on the second and fourth weeks postoperatively, to detect silent DVT. Results. Nine patients out of 150 patients developed silent DVT (6%). All patients among group A were subjected to mechanical thromboprophylaxis only (12%) [P = .247, relative risk: .45, 95% confidence interval; .37-.62]. There was no silent DVT among group B who received combined mechanical and chemical thromboprophylaxis. No bleeding complications were reported in both groups. Conclusion. Combined mechanical and mechanical thromboprophylaxis is effective and safe in the prevention of silent DVT after laparoscopic bariatric surgery. Trial registration: The trial was registered in the Thai Clinical Trials Registry (TCTR20200127002) on January 20, 2020 retrospectively.

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Purpose: To assess the quality and accuracy of glaucoma referrals from ophthalmologist. Methods: Retrospective review of patients chart with referral letter to a tertiary glaucoma center between January and December 2017. Patients aged <16 years, lens-induced glaucoma, uveitic glaucoma, and glaucoma following retinal and corneal surgery were excluded. Results: A total of 184 patients referred by 55 ophthalmologists were included. Mean patient age (SD) was 57.8 ± 14 years. Intraocular pressure was not documented in the referral letter in 113 (61%) patients, gonioscopy in 174 (95%) patients, disc findings in 149 (81%) patients, and visual fields in 175 (95%) patients. Thirteen (37%) of the 35 patients referred as open angle glaucoma were found to have angle closure glaucoma. Pseudoexfoliation glaucoma was diagnosed in 29 (16%) patients, of which 18 were missed by the referring ophthalmologist. Conclusion: In our study >90% of referral letter did not have the essential parameters. A standard template for glaucoma referral is suggested, which will help the patient to get better transfer of care.

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Most of the widely used scales to evaluate scars are subjective relying on clinical observations. There is a growing need to find out a noninvasive objective tool for this purpose. The study is aimed at evaluating the value of the high-resolution ultrasound in the assessment of the scars when compared with a clinical evaluation scoring system, the Vancouver Scar Scale (VSS). The study included 22 patients with hypertrophic scars or keloids. At baseline, scars were assessed using the Vancouver Scar Scale and high-resolution ultrasound (13-MHz probe). Patients received three Nd:YAG laser sessions (100 J/cm2 fluence, pulse width 50 ms, frequency rate 2 Hz, and spot size 7 mm) at 1-month intervals. Pulses were applied in a painting motion till reaching the clinical end point which is mild erythema. After the 3rd session, lesions were evaluated again using the VSS and the high-resolution ultrasound. The Vancouver Scar Scale decreased significantly after treatment in both treatment groups. Radiological evaluations showed significant improvement in lesion thickness and echogenicity, but not the lesion vascularity. There was a significant difference between the improvement percent measured by the VSS and high-resolution ultrasound (p = 0.001). The percent of HTS improvement was higher than that of keloid improvement. Among all the studied variables, it seems that female sex is the only factor which predicts better treatment outcome. The combined clinical and radiological assessment of scars is helpful in assessing these lesions and comparing the efficacy of different treatment modalities.

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One of the most famous algorithms that appeared in the area of image segmentation is the Fuzzy C-Means (FCM) algorithm. This algorithm has been used in many applications such as data analysis, pattern recognition, and image segmentation. It has the advantages of producing high quality segmentation compared to the other available algorithms. Many modifications have been made to the algorithm to improve its segmentation quality. The proposed segmentation algorithm in this paper is based on the Fuzzy C-Means algorithm adding the relational fuzzy notion and the wavelet transform to it so as to enhance its performance especially in the area of 2D gel images. Both proposed modifications aim to minimize the oversegmentation error incurred by previous algorithms. The experimental results of comparing both the Fuzzy C-Means (FCM) and the Wavelet Fuzzy C-Means (WFCM) to the proposed algorithm on real 2D gel images acquired from human leukemias, HL-60 cell lines, and fetal alcohol syndrome (FAS) demonstrate the improvement achieved by the proposed algorithm in overcoming the segmentation error. In addition, we investigate the effect of denoising on the three algorithms. This investigation proves that denoising the 2D gel image before segmentation can improve (in most of the cases) the quality of the segmentation.

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BACKGROUND/AIMS: Vascular diseases are a major cause of morbidity and mortality in end-stage renal disease (ESRD) patients and they cannot be explained entirely by the prevalence of traditional risk factors for atherosclerosis. The role of hyperhomocysteinemia as an additional risk factor in the development of accelerated atherosclerosis and/or thrombosis in these patients has been suggested possibly due to homocysteine (Hcy) induced endothelial cell injury. This study was aimed at evaluation of the Hcy status in children with chronic renal failure (CRF) especially in those suffering from ESRD and the possible role of folic acid and vitamin B12 therapy in the correction of hyperhomocysteinemia if present. METHODS: This study included 40 patients with CRF, 30 on regular hemodialysis (HD) treatment (group I) and 10 on conservative (medical) treatment (group II) in comparison to 20 healthy age- and sex-matched controls (group III). The basal serum levels of Hcy, folic acid and vitamin B12 as well as plasma level of activated protein C resistance (APC-R) were measured in patients and controls. RESULTS: The mean serum Hcy was significantly higher in those on regular HD (17.9 +/- 10.07 micromol/l) in comparison to those on conservative treatment (8.05 +/- 2.99 micromol/l) (p < 0.001) and controls (7.07 +/- 2.24 micromol/l) (p < 0.001), while there was no significant variation between the latter two groups. The mean values of APC-R, folic acid and vitamin B12 failed to show any significant difference in the three studied groups. No significant difference in the basal Hcy level between patients with previous history of vaso-occlusive disease and those without was found. Half of the patients on regular HD (group Ia) (n = 15) were given folic acid as 50 mg of 5-formyl-tetrahydrofolate (the active form of folic acid) intravenously once weekly after the dialysis session for 4 weeks. The other half (group Ib) (n = 15) received in addition to folic acid therapy, vitamin B12 1,000 microg hydroxycobalamine once intramuscularly. After therapy the mean Hcy decreased significantly in those who received folic acid and vitamin B12 (7.80 +/- 3.77 micromol/l) (p < 0.001) to a level comparable to the basal levels in conservative and control groups, whereas a non-significant decrease was found in those who received folic acid only (13.3 +/- 11.47 micromol/l) (p > 0.05). CONCLUSIONS: Hcy is high in children with ESRD on regular HD and combined therapy of the active form of folic acid and vitamin B12 is of value in decreasing Hcy values comparable to that in controls.

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