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Clustering using deep autoencoders has been thoroughly investigated in recent years. Current approaches rely on simultaneously learning embedded features and clustering the data points in the latent space. Although numerous deep clustering approaches outperform the shallow models in achieving favorable results on several high-semantic datasets, a critical weakness of such models has been overlooked. In the absence of concrete supervisory signals, the embedded clustering objective function may distort the latent space by learning from unreliable pseudo-labels. Thus, the network can learn non-representative features, which in turn undermines the discriminative ability, yielding worse pseudo-labels. In order to alleviate the effect of random discriminative features, modern autoencoder-based clustering papers propose to use the reconstruction loss for pretraining and as a regularizer during the clustering phase. Nevertheless, a clustering-reconstruction trade-off can cause the \textit{Feature Drift} phenomena. In this paper, we propose ADEC (Adversarial Deep Embedded Clustering) a novel autoencoder-based clustering model, which addresses a dual problem, namely, \textit{Feature Randomness} and \textit{Feature Drift}, using adversarial training. We empirically demonstrate the suitability of our model on handling these problems using benchmark real datasets. Experimental results validate that our model outperforms state-of-the-art autoencoder-based clustering methods.

The geographical location of Egypt at the crossroads of several major cultural areas between North Africa and the Middle East has contributed to its population history.To analyse the genetic structure of the population living in two geographical parts of Egypt.A sample of 112 Egyptians from the North African part of Egypt (Ismailia sample) and a sample of 52 Egyptians from the Asian part Sinai, have been analysed using 10 Alu insertion polymorphisms.The results of the present study showed a significant genetic difference between the Sinai and Ismailia samples. The latter showed an evident genetic affinity with North African populations; whereas the Sinai sample was found to be genetically closer to the Middle East populations. The Sinai sample showed a low average heterozygosity, unlike that found in the Ismailia sample.This study provides new insights into the genetic structure of the Egyptian population living in a land bridge between Africa and Asia. Results suggest a genetic discontinuity between the Sinai population and that of the North African part of Egypt. This discontinuity would have been maintained thanks to geo-climatic and social factors.

ObjectiveTo evaluate whether the clinical benefit and relapse rates in anti-muscle-specific kinase (MuSK) myasthenia gravis (MG) differ depending on the protocol of rituximab followed. MethodsThis retrospective multicentre study in patients with MuSK MG compared three rituximab protocols in terms of clinical status, relapse, changes in treatment, and adverse side effects. The primary effectiveness endpoint was clinical relapse requiring a further infusion of rituximab. Survival curves were estimated using Kaplan-Meier methods and survival analyses were undertaken using Cox proportional-hazards models. ResultsTwenty-five patients were included: 11 treated with protocol 4 + 2 (375 mg/m(2)/4 weeks, then monthly for 2 months), five treated with protocol 1 + 1 (two 1 g doses 2 weeks apart), and nine treated with protocol 4 (375 mg/m(2)/4 weeks). Mean follow-up was 5.0 years (SD 3.3). Relapse occurred in 18.2%, 80%, and 33.3%, and mean time to relapse was 3.5 (SD 1.5), 1.1 (SD 0.4), and 2.5 (SD 1.4) years, respectively. Based on Kaplan-Meier estimates, patients treated with protocol 4 + 2 had fewer and later relapses than patients treated with the other two protocols (log-rank test P = 0.0001). Patients treated with protocol 1 + 1 had a higher risk of relapse than patients treated with protocol 4 + 2 (HR 112.8, 95% CI, 5.7-2250.4, P = 0.002). Patients treated with protocol 4 showed a trend to a higher risk of relapse than those treated with protocol 4 + 2 (HR 9.2, 95% CI 0.9-91.8, P = 0.059). InterpretationThis study provides class IV evidence that the 4 + 2 rituximab protocol has a lower clinical relapse rate and produces a more durable response than the 1 + 1 and 4 protocols in patients with MuSK MG. I. Illa received research support from the Fondo de Investigacion en Salud, Instituto de Salud Carlos III, Ministry of Health (Spain), FIS PI16/01440 (Fondos FEDER). E. Cortes-Vicente was supported by a FIS grant (CM16/00096) from Fondo de Investigacion en Salud, Instituto de Salud Carlos III, Ministry of Health (Spain) and Fondo Social Europeo.

AbstractOnly a few studies have assessed the long-term duration of the humoral immune response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).In this nationwide longitudinal study from the Faroe Islands with close to full participation of all individuals on the Islands with PCR confirmed COVID-19 during the two waves of infections in the spring and autumn 2020 (n=172 & n=233), samples were drawn at three longitudinal time points (3, 7 and 12 months and 1, 3 and 7 months after disease onset, respectively).Serum was analyzed with a direct quantitative IgG antibody binding ELISA to detect anti–SARS-CoV-2 spike RBD antibodies and a commercially available qualitative sandwich RBD ELISA kit measuring total antibody binding.The seropositive rate in the convalescent individuals was above 95 % at all sampling time points for both assays. There was an overall decline in IgG titers over time in both waves (p < 0.001). Pairwise comparison showed that IgG declined significantly from the first sample until approximately 7 months in both waves (p < 0.001). After that, the antibody level still declined significantly (p < 0.001), but decelerated with an altered slope remaining fairly stable from 7 months to 12 months after infection. Interestingly, the IgG titers followed a U-shaped curve with higher antibody levels among the oldest (67+) and the youngest (0– 17) age groups compared to intermediate groups (p < 0.001).Our results indicate that COVID-19 convalescent individuals are likely to be protected from reinfection up to 12 months after symptom onset and maybe even longer. We believe our results can add to the understanding of natural immunity and the expected durability of SARS-CoV-2 vaccine immune responses.

Ramanathan K Kasimanickam,1 Ashish Ranjan,2 GV Asokan,3 Vanmathy R Kasimanickam,1 John P Kastelic41Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA; 2Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK, USA; 3College of Health Sciences, University of Bahrain, Salmaniya Medical Complex, Manama, Bahrain; 4Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, CanadaAll authors contributed equally to this workAbstract: Bacteria growing as adherent biofilms are difficult to treat and frequently develop resistance to antimicrobial agents. To counter biofilms, various approaches, including prevention of bacterial surface adherence, application of device applicators, and assimilation of antimicrobials in targeted drug delivery machinery, have been utilized. These methods are also combined to achieve synergistic bacterial killing. This review discusses various multimodal technologies, presents general concepts, and describes therapies relying on the principles of electrical energy, ultrasound, photodynamics, and targeted drug delivery for prevention and treatment of biofilms.Keywords: biofilm, antimicrobial, drug carrier, hybrid technology, nanotechnology

الملخص: أهداف البحث: يعد فقر الدم المنجلي من أكثر أمراض خضاب الدم المنتشرة في العالم. ومن مضاعفات المرض تكون حصى المرارة وتتفاوت الأعراض المصاحبة لحصى المرارة من كونها صامتة ولا تظهر على المريض أي أعراض، إلى حدوث التهابات المرارة، والقنوات الصفراوية وكذلك البنكرياس. تهدف هذه الدراسة إلى تحديد نسبة حدوث حصوات المرارة لدى الأطفال المصابين بفقر الدم المنجلي في السعودية. طرق البحث: تمت الدراسة عن طريق مراجعة السجلات الطبية لجميع المرضى الذين تتراوح أعمارهم ما بين عامين إلى ثمانية عشر عاما المصابين بفقر الدم المنجلي. ودراسة عوامل الخطورة المرتبطة بتكوين حصوات المرارة. النتائج: أظهرت النتائج حدوث حصوات المرارة بنسبة ٢٧٪ لدى المرضى المصابين بفقر الدم المنجلي عند متوسط عمر سبعة سنوات تقريبا. ومن عوامل الخطورة التي ساهمت في زيادة تكون الحصوات بشكل ملحوظ هي زيادة العمر، وارتفاع نسبة خضاب الدم من النوع ''س'' وزيادة حجم كريات الدم الحمراء. كما لوحظت زيادة نسبة الحصى لدى الذكور عن الاناث، والسعوديين عن غيرهم، ومرضى فقر الدم المنجلي عن فقر الدم المنجلي والبحر المتوسط، لكن هذه الاختلافات لم تكن ذات مدلولات إحصائية. الاستنتاجات: وجدت الدراسة أن نسبة حدوث حصى المرارة عالية لدى الأطفال المصابين بفقر الدم المنجلي. وكانت العلاقة مع العمر وزيادة نسبة خضاب الدم من النوع ''س'' وزيادة حجم كريات الدم الحمراء علاقة ذات دلالة إحصائية. Abstract: Objective: Sickle cell disease is one of the most common inherited hemoglobinopathies in the world. Chronic haemolysis predisposes individuals to the development of bilirubinate cholelithiasis, which can be asymptomatic or can result in cholecystitis, choledocholithiasis, cholangitis, and gallstone pancreatitis. We aimed to determine the prevalence of cholelithiasis and associated gallstone disease among patients with paediatric sickle cell disease in a Saudi hospital. Methods: This retrospective study was conducted among all patients aged between 2 and 18 years. We reviewed the medical records of patients diagnosed with sickle cell anaemia. Mean and standard deviation were calculated for quantitative variables, and the Student t-test was used to compare means. The chi-square test was used to assess those risk factors possibly associated with cholelithiasis. A P-value of ≤0.05 was considered statistically significant. Results: Approximately 75% of participants developed cholelithiasis (27.5%) at a mean age of 6.9 ± 3.4 years. The frequency of cholelithiasis was significantly higher with increasing age (40.8% in participants 12 years and older) and among those with high levels of haemoglobin S (Hb S) and mean corpuscular volume (MCV). Moreover, cholelithiasis was more frequent among males than females, Saudis than non-Saudis, and in those with sickle cell disease than in those with sickle thalassemia. However, these differences were not statistically significant. Conclusion: In this study, the prevalence of cholelithiasis among children with sickle cell anaemia was found to be high. This association was significantly increased with age and high levels of MCV and Hb S. الكلمات المفتاحية: حصى المرارة, فقر الدم المنجلي, Keywords: Cholelithiasis, Gallstones, Sickle cell anaemia

Abstract Monitoring marine biodiversity is costly and practical solutions have to be implemented to identify species and their preferred habitats, particularly in this era of rapid global change. Citizen science has proven to be effective and with high potential for monitoring efforts, and has been extensively applied to biodiversity. We have used the citizen science approach to engage the general public and stakeholders to contribute improving the current knowledge of sea snake biodiversity in Qatar and the Gulf Region. Logistic regression analysis using demographic data from interview surveys conducted in Qatar has indicated that the people having seen more sea snakes are older than 30 years and are Qatari citizens and/or fishermen from India. Of the ten species of sea snakes listed in the literature to be present in the Gulf Region, most of them have been reported for Qatar, Bahrain, United Arab Emirates and Saudi Arabia. However, the number of species present is often assumed based on their occurrence within the Arabian Gulf rather than on actual captures and appropriate identification. The creation of marine reference biological scientific collections to properly identify the species and make accurate biodiversity inventories is an urgent priority for the countries in the Gulf region. To this end, contributions by stakeholders and the general public for this study have proven to be very useful. However a larger networking with local and international scientists and stakeholders is still needed to adequately survey the country’s current biodiversity, identify research priorities and eventually provide the scientific input needed to assist biodiversity management related to renewable resource management and marine conservation in the Arabian Gulf Region.