90 research outputs found

    Covid-19 detection using modified xception transfer learning approach from computed tomography images

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    The significance of efficient and accurate diagnosis amidst the unique challenges posed by the COVID-19 pandemic underscores the urgency for innovative approaches. In response to these challenges, we propose a transfer learning-based approach using a recently annotated Computed Tomography (CT) image database. While many approaches propose an intensive data preprocessing and/or complex model architecture, our method focuses on offering an efficient solution with minimal manual engineering. Specifically, we investigate the suitability of a modified Xception model for COVID-19 detection. The method involves adapting a pre-trained Xception model, incorporating both the architecture and pre-trained weights from ImageNet. The output of the model was designed to make the final diagnosis decisions. The training utilized 128 batch sizes and 224x224 input image dimensions, downsized from standard 512x512. No further da processing was performed on the input data. Evaluation is conducted on the 'COV19-CT-DB' CT image dataset, containing labeled COVID-19 and non-COVID-19 cases. Results reveal the method's superiority in accuracy, precision, recall, and macro F1 score on the validation subset, outperforming the VGG-16 transfer model and thus offering enhanced precision with fewer parameters. Furthermore, compared to alternative methods for the COV19-CT-DB dataset, our approach exceeds the baseline approach and other alternatives on the same dataset. Finally, the adaptability of the modified Xception transfer learning-based model to the unique features of the COV19-CT-DB dataset showcases its potential as a robust tool for enhanced COVID-19 diagnosis from CT images

    Psikolojik İhtiyaçlar Ölçeğinin Geliştirilmesi: Güvenirlik ve Geçerlik Çalışması

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    Bu araştırma genç yetişkin bireylerin psikolojik ihtiyaçlarını belirlemek amacıyla geliştirilmiş olan“Psikolojik ihtiyaçlar Ölçeğinin” geçerlik ve güvenirliğini test etmek amacıyla yapılmıştır. Ölçeğingeliştirilmesi sırasıyla; madde havuzu oluşturulabilmesi için ön veri toplama, nitel verilerin analiziyapılarak ölçeğin; maddelerini hazırlama, kapsam geçerliği için uzman görüşü alma, denemeuygulaması, verilerin analizinde Açımlayıcı Faktör Analizi ve Doğrulayıcı Faktör Analizi ile aracıngüvenirlik - geçerlik çalışmasının yapılması, şeklinde bir yol izlenmiştir. Araştırmanın örneklemini2019-2020 yılı içinde Kafkas üniversitesinin farklı fakültelerinde öğrenim görmekte olan 18-27 yaşarası toplam 1075 üniversite öğrencisi oluşturmaktadır. Ölçeğin Taslak maddeleri, Murray’inkuramında yer verdiği 25 psikolojik ihtiyacı ve toplam 356 maddeyi kapsayacak biçimdeoluşturulmuştur. Analiz sonuçlarına göre güvenilir bulunmayan maddeler çıkarılmış ve son olarak 50maddelik ve 4 boyutlu bir ölçek yapısı ortaya çıkmıştır. Bu boyutlar sırasıyla 1. faydalı olma/şefkatgösterme (olumlu sosyal davranış) 20 maddeden (Açıklanan varyans %22.47), 2. cinsellik 9 maddeden(Açıklanan varyans %13.59), 3. üstünlük/başatlık/gösteriş yapma 12 maddeden (Açıklanan varyans%13.68), 4. kendini açma 9 maddeden (Açıklanan varyans %9.21) maddeden oluşmaktadır. Ölçek%58.96 luk bir varyans açıklamıştır. Bu değerler ölçeğin açıkladığı varyans yükünün yeterli olduğunugöstermektedir. Ölçeğin güvenirliği için madde analizine bağlı olarak hesaplanan Cronbach Alpha içtutarlılık katsayıları .909 olarak bulunmuştur. Sonuç olarak, üniversite öğrencileri örneklemindegeliştirilen Psikolojik İhtiyaçlar Ölçeğinin yetişkinlerin psikolojik ihtiyaçlarını ölçmede geçerli vegüvenilir bir araç olduğu ortaya konmuştur

    Choroidal Thickness in Patients with Mild Cognitive Impairment and Alzheimer’s Type Dementia

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    Aim. To asses both choroidal thickness differences among Alzheimer’s type dementia (ATD) patients, mild cognitive impairment (MCI) patients, and healthy control (C) subjects and choroidal thickness relationships with cognitive performance. Methods. A total of 246 eyes of 123 people (41 ATD, 38 MCI, and 44 healthy C subjects) were included in this study. Complete ophthalmological and neurological examination was performed in all subjects. Choroidal thicknesses (CT) were measured at seven locations: the fovea, 500-1500-3000 μm temporal and 500-1500-3000 μm nasal to the fovea by enhanced depth imaging optical coherence tomography (EDI-OCT). Detailed neurological examination including mini mental state examination (MMSE) test which evaluates the cognitive function was applied to all participants. Results. The ages and genders of all participants were similar in all groups. Compared with healthy C subjects, the CT measurements at all regions were significantly thinner both in patients with ATD and in patients with MCI than in healthy C subjects (p<0.05). The MMSE scores were significantly different among ATD patients, MCI patients, and healthy C subjects. They were 19.3±1.8, 24.8±0.9, and 27.6±1.2 in ATD, MCI, and healthy controls, respectively (p<0.001). There were also significant correlation between MMSE score and choroidal thickness at each location (p<0.05). Conclusions. CT was reduced in ATD patients and MCI patients. Since vascular structures were affected in ATD patients and MCI patients, they had thin CT. Besides CT was correlated with degree of cognitive impairment. Therefore CT may be a new biomarker in diagnosis and follow-up of MCI and ATD patients

    Treatment of Vegetable Oil Refining Wastes

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    Kaya, D, and Hung, YT (2020). Treatment of vegetable oil refining wastes. In: "Evolutionary Progress in Science, Technology, Engineering, Arts, and Mathematics (STEAM)", Wang, Lawrence K. and Tsao, Hung-ping (editors). Volume 2, Number 2, February 2020; 80 pages. Lenox Institute Press, Newtonville, NY, 12128-0405, USA. No. STEAM-VOL2-NUM2-FEB2020; ISBN 978-0-9890870-3-2. --------------- ABSTRACT: The common vegetable oils are soybean, sesame, sunflower, corn, canola, and cotton seeds. Their yields, compositions and physical and chemical properties determine their usefulness in various applications aside edible uses. Crude oils obtained by pressing of such vegetable seeds are not usually considered to be edible before the removal of various nonglyceride compounds through operations known as refining. The refining processes remove undesirable materials such as phospholipids, monoacylglycerols, diacylglycerols, free fatty acids, colour and pigments, oxidised materials, etc., but, may also remove valuable minor components such as antioxidants and vitamins (carotenes and tocopherols). The major steps involved in chemical refining include degumming, neutralizing, bleaching, and deodorizing which are the main sources of the effluent. The chapter covers refining steps, its environmental impacts, waste characterization, source reduction, recovery and treatment technologies

    Cognitive performance of primary open-angle glaucoma and normal-tension glaucoma patients

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    ABSTRACT Purpose: To assess cognitive performance differences among primary open-angle glaucoma (POAG) patients, normal-tension glaucoma (NTG) patients, and healthy control (C) subjects. Methods: A total of 60 participants (20 POAG, 20 NTG, and 20 C subjects) were included in this study. A detailed ophthalmologic examination was performed on all participants. A spectral domain-optical coherence tomography (SD-OCT) system was used to measure the ganglion cell-inner plexiform layer (GC-IPL) and retinal nerve fiber layer (RNFL) thicknesses. To assess the cognitive performance of all participants, detailed neurological examinations, including the mini-mental state examination (MMSE), were performed by the same neurologist. Results: There were no significant differences among the groups in terms of age (p =0.348) or gender (p =0.935). The mean RNFL thicknesses were significantly different among the groups (85.2 ± 14.7, 76.8 ± 10.3, and 91.4 ± 7.7 µm in the POAG, NTG, and C subjects, respectively; p <0.001). The mean GC-IPL thicknesses were 77.5 ± 9.7 µm in the POAG group, 73.4 ± 7.8 µm in the NTG group, and 78.8 ± 3.8 µm in the C group. Differences among the groups were not statistically significant (p =0.085). MMSE scores were 26.1 ± 1.4, 25.7 ± 2.3, and 28.8 ± 0.9 in the POAG, NTG, and C groups, respectively. There were significant differences among the three groups (p <0.001). Specifically, there were significant differences between the NTG and C groups (p <0.001), and between the POAG and C groups (p =0.001). There was no significant difference between the POAG and NTG groups (p =0.595). Conclusions: There appear to be similar risk factors in glaucoma and neurodegenerative disorders that cause deterioration in cognitive performance. Comparing the low MMSE scores of the POAG and NTG patients with the scores of healthy C participants supports our hypothesis. Consequently, it is recommended that a neurologist should also examine glaucoma patients

    Variability in RT-qPCR assay parameters indicates unreliable SARS-CoV-2 RNA quantification for wastewater surveillance

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    Due to the coronavirus disease 2019 (COVID-19) pandemic, wastewater surveillance has become an important tool for monitoring the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within communities. In particular, reverse transcription-quantitative PCR (RT-qPCR) has been used to generate large datasets aimed at detecting and quantifying SARS-CoV-2 RNA in wastewater. Although RT-qPCR is rapid and sensitive, there is no standard method yet, there are no certified quantification standards, and experiments are conducted using different assays, reagents, instruments, and data analysis protocols. These variations can induce errors in quantitative data reports, thereby potentially misleading interpretations, and conclusions. We review the SARS-CoV-2 wastewater surveillance literature focusing on variability of RT-qPCR data as revealed by inconsistent standard curves and associated parameters. We find that variation in these parameters and deviations from best practices, as described in the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines suggest a frequent lack of reproducibility and reliability in quantitative measurements of SARS-CoV-2 RNA in wastewater

    Passive Sampling to Scale Wastewater Surveillance of Infectious Disease: Lessons Learned From COVID-19

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    Much of what is known and theorized concerning passive sampling techniques has been developed considering chemical analytes. Yet, historically, biological analytes, such as Salmonella typhi, have been collected from wastewater via passive sampling with Moore swabs. In response to the COVID-19 pandemic, passive sampling is re-emerging as a promising technique to monitor SARS-CoV-2 RNA in wastewater. Method comparisons and disease surveillance using composite, grab, and passive sampling for SARS-CoV-2 RNA detection have found passive sampling with a variety of materials routinely produced qualitative results superior to grab samples and useful for sub-sewershed surveillance of COVID-19. Among individual studies, SARS-CoV-2 RNA concentrations derived from passive samplers demonstrated heterogeneous correlation with concentrations from paired composite samples ranging from weak (R2 = 0.27, 0.31) to moderate (R2 = 0.59) to strong (R2 = 0.76). Among passive sampler materials, electronegative membranes have shown great promise with linear uptake of SARS-CoV-2 RNA observed for exposure durations of 24 to 48 h and in several cases RNA positivity on par with composite samples. Continuing development of passive sampling methods for the surveillance of infectious diseases via diverse forms of fecal waste should focus on optimizing sampler materials for the efficient uptake and recovery of biological analytes, kit-free extraction, and resourceefficient testing methods capable of rapidly producing qualitative or quantitative data. With such refinements passive sampling could prove to be a fundamental tool for scaling wastewater surveillance of infectious disease, especially among the 1.8 billion persons living in low-resource settings served by non-traditional wastewater collection infrastructure

    Length-weight relationships of 28 fish species caught from demersal trawl survey in the Middle Black Sea, Turkey

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    This study provides updated the length-weight relationships and Fulton's condition factor of 28 fish species belonging to 23 families from the Black Sea. Samples were collected along the depths between 0-100 meters by demersal trawl surveys conducted seasonally from May 2017 to September 2019. A total of 83,885 specimens were collected. The length-weight relationships and Fulton's condition factor, minimum, maximum and mean lengths, total weights, descriptive statistics, and growth type were provided for all the species. The results indicate that LWR parameters of b varied from 2.2039 to 3.737 and Fulton's condition factor varied between 0.004 and 1.18. These findings could be useful for monitoring and management of sustainable fisheries and habitat health

    Monkeypox Outbreak: Wastewater and Environmental Surveillance Perspective

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    Monkeypox disease (MPXD), a viral disease caused by monkeypox virus (MPXV), is an emerging zoonotic disease endemic in some countries of Central and Western Africa but seldom reported outside the affected region. Since May 2022, MPXD has been reported at least in 74 countries globally, prompting the World Health Organization to declare the MPXD outbreak a Public Health Emergency of International Concern. As of July 24, 2022, 92% (68/74) of the countries with reported MPXD cases had no historical MPXD case reports. From the One Health perspective, the spread of MPXV in the environment poses a risk not only to humans but also to small mammals and may, ultimately, spread to potent novel host populations. Wastewater-based surveillance (WBS), has been extensively utilized for monitoring communicable diseases, particularly during the ongoing coronavirus disease, the COVID-19 pandemic It helped to monitor infectious disease caseloads as well as specific viral variants circulating in communities. The detection of MPXV DNA in various body fluids, including respiratory and nasal secretions, saliva, urine, feces, and semen of infected individuals, supports the possibility of using WBS as an early proxy for the detection of MPXV infections. WBS of MPXV DNA can be used to monitor MPXV activity/trends in sewerage network areas even before detecting laboratory-confirmed clinical cases within a community. However, several factors affect the detection of MPXV in wastewater including, but not limited to, routes and duration time of virus shedding by infected individuals, infection rates in the relevant affected population, environmental persistence, the processes and analytical sensitivity of the used methods. Further research is needed to identify the key factors that impact the detection of MPXV biomarkers in wastewater and improve the utility of WBS of MPXV as an early warning and monitoring tool for safeguarding human health. In this review, we shortly summarize aspects of MPXV outbreak relevant to wastewater monitoring and discuss the challenges associated with WBS.Peer reviewe
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