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3D printed stacked antenna for WLAN drone communication
No full textUnmanned Aerial Vehicle or drone technologies have spread rapidly into areas such as search and rescue, monitoring, surveillance, emergency assistance, delivery of goods, and aerial photography and video. The design of compact, low cost, and multi resonant frequency antenna models has become a critical research study for these applications. Although one of the most popular antenna designs that have such specifications are Microstrip Patch Antennas (MPA), they have the handicap of narrow operation band. Stacking is one of the techniques that not only improve the bandwidth of the antenna but also makes it possible to increase its gain and expand its operation band. Herein, design of a low cost low weight wideband Stacked (MPA) design suitable for WLAN drone communication applications is studied. By using unique features of 3D printing technology the proposed design will be prototyped for satisfying the aimed design goals. For this purpose, the antenna is simulated in CST Microwave Studio by a 3D electromagnetic based model, and maximum gain level that is approaching 9.3 dBi at 5.8 GHz frequency has been achieved. Next, the antenna design is prototyped using 3D printing technology, and a gain level of 7.5, 8.3 dBi are measured at the operating frequencies 5.2 GHz and 5.8 GHz WLAN applications. The results show that the proposed antenna achieves higher performance than its counterparts in literature based on measures such as operation bandwidth, gain, size and manufacturing costs. © Yildiz Technical University. All Rights Reserved
Opinions of female academicians on oocyte freezing: a qualitative study
No full textOBJECTIVE: The aim of this study was to evaluate the opinions of female academicians about oocyte freezing. METHODS: This qualitative study included 12 single academic women who had not yet entered menopause, did not have children, and were continuing their doctoral education in Istanbul, Turkey, between August and September 2022. Data were collected with semi-structured interviews and evaluated by content analysis. RESULTS: Three main themes were "Difficulty of fertility in academics," "Advantages of oocyte freezing," and "Concerns about oocyte freezing." Participants mostly had positive attitudes about the advantages of oocyte cryopreservation, but they had concerns about pregnancies obtained with frozen oocytes. CONCLUSION: The academic women attributed fertility as an obstacle to their career and experienced anxiety about fertility. They were aware of the advantages of oocyte cryopreservation; however, they defined the pregnancy with oocyte freezing as artificial
The ailments that stem from cheese and relevant precautions taken in the Ottoman Empire from the 19th century to the 20th century
No full textThe increase in cheese production, sale, and consumption due to the settled lives of societies has led to an increase in cheese-related diseases. It has become essential to better understand cheese-borne diseases and to develop control measures. In this study, cheese-related diseases and precautions taken in the Ottoman Empire from the 19th to the 20th centuries were investigated in Ottoman archival sources. Of these documents, cheese spoilage was detected in 12 and cheese-related disease in 9. Cheeses that caused diseases or disorders in the relevant period were called spoiled cheese. One document states that a person died of a cheese-borne illness. Cheese poisoning occurs mainly from unsalted, fresh cheeses. It has been determined that tin-free copper pots were used in cheese production and sales and covered with herbs such as hemlock during maturation. In the relevant period, microbiological and chemical analyses of cheeses in terms of health were carried out in food control laboratories. Since the mercury chloride solution is used to disinfect animal udders, it has been stated that it contaminates the milk used in cheese production. Authorities have requested a boric acid solution (5% boric acid in hot water) instead of this solution for udder disinfection. In the Ottoman Empire, it was requested to take necessary sanitation and hygiene measures to prevent spoilage and cheese-related diseases in the production areas or sales places of cheese. Clean and tinned containers should be used in cheese production, storage, and sale, and poisonous herbs should not be used during cheese ripening. It was also essential to analyze them in laboratories at internal and external customs. Knowing the precautions taken in the past to prevent the deterioration of food or the occurrence of diseases has led to modern food safety practices being applied today
Reversible Logic-Based Hexel Value Differencing-A Spatial Domain Steganography Method for Hexagonal Image Processing
No full textThe field of steganography has witnessed considerable advancements in square-pixel-based image processing (SIP). However, the application of steganography in Hexel (Hexagonal pixel)-based Image Processing (HIP) is still underexplored. This study introduces a pioneering spatial steganography method called the Reversible Logic-Based Hexel Value Differencing (RLBHVD) method in the HIP domain. Our approach draws inspiration from Pixel-Value-Differencing (PVD), a SIP fundamental spatial-domain (S-D) steganography method. Initially, the image is transformed into the HIP domain using the custom software infrastructure developed for this project. Due to the absence of commercial equipment capable of producing HIP-domain images, traditional digital imaging systems are employed with their sensor components, analog-to-digital conversion units, and square-pixel-based displays. Once the image is converted, it is partitioned into standardized heptads, each comprising seven hexels. Simultaneously, the secret message is segmented for embedding into the hexels within each heptad. Unlike SIP-domain PVD, which embeds segments into independent pixel pairs, our method performs iterative embedding within each heptad. Additionally, we leverage Feynman gates, a core element of reversible logic, to achieve retrieval of both the cover image and the secret message. Unlike PVD in SIP, our approach enables reversibility in the recovery process. Experimental results demonstrate that our proposed method, RLBHVD, outperforms its SIP counterpart, PVD, by achieving a low Mean Squared Error (MSE), high Peak Signal-to-Noise Ratio (PSNR), and significant similarity between the stego-image and cover image histograms. These findings highlight the efficacy and superiority of our HIP-based steganography approach in comparison to existing SIP methods
Comparison of Compassion Fatigue, Burnout and Compassion Satisfaction of Oncology-Hematology & Dialysis Nurses
No full textBackground: It is known that health professionals who work with chronic patients for a long time are at risk in terms of compassion fatigue and burnout. Purpose: The study aims to compare the levels of compassion fatigue, burnout, and compassion satisfaction of nurses working on oncology-hematology and dialysis and determine the predictors. Methods: This study was carried out using descriptive and correlational research design. The research was conducted with 278 nurses. Participants were enrolled using a convenience sampling technique from the oncology-hematology inpatient services, outpatient chemotherapy units, and bone marrow transplant units and dialysis nurses of purposively selected hospitals in Istanbul, Turkey. Personal information form and Professional Quality of Life-IV. Potential predictors were analyzed using univariate analysis. We conducted multiple stepwise linear regression analyses to reveal the outcome variables. Results: A sub-analysis comparing the dialysis specialty with the oncology-hematology revealed that dialysis nurses report significantly higher compassion fatigue scores than oncology nurses. Working willingly in the current unit and the level of received social support were determined as predictors for all outcome variables. Conclusions: This is the first study comparing compassion fatigue, burnout, and compassion satisfaction levels of oncology-hematology and dialysis nurses. This study indicates the need for nurse managers to be aware of compassion fatigue and plan compassion fatigue prevention programs. In addition, this study guides the interventional studies to be conducted in the future
LC-MS/MS and GC-MS profiling, antioxidant, enzyme inhibition, and antiproliferative activities of Thymus leucostomus HAUSSKN. & VELEN. extracts
No full textThe chemical composition as well as antioxidant, antiproliferative, and enzyme inhibition activities of extracts from aerial parts of Thymus leucostomus H ausskn. & V elen. obtained with hexane, methanol, and water were evaluated. Results showed that the methanol extract had significantly (p < 0.05) the highest total phenolic content (TPC; 107.80 mg GAE/g) and total flavonoids content (TFC; 25.21 mg RE/g) followed by the aqueous extract (102.72 mg GAE/g and 20.88 mg RE/g, respectively). LC-MS/MS-guided profiling of the three extracts revealed that rosmarinic acid (34.8%), hesperetin (42.9%), and linoleic acid (18%) were the dominant compounds in the methanol, aqueous and hexane extracts, respectively. GC-MS analysis of the hexane extract showed that ɣ-sitosterol (29.9%) was the major constituent. The methanol extract displayed significantly (p < 0.05) the highest Cu++, Fe+++, and Mo(VI) ions scavenging and reducing properties while the aqueous extract exerted significantly (p < 0.05) the highest metal chelating power (42.51 mg EDTAE/g). Both the hexane and methanol extracts effectively inhibited the acetylcholinesterase enzyme (2.63 and 2.65 mg GALAE/g, respectively) while the former extract exerted significantly (p < 0.05) the highest butyrylcholinesterase (2.32 mg GALAE/g), tyrosinase (19.73 mg KAE/g), and amylase (1.16 mmol ACAE/g) inhibition capacity. The aqueous extract exhibited the best glucosidase inhibition property (0.49 mmol ACAE/g). The methanol and hexane extracts exerted a higher cytotoxic effect on HT-29 (IC50: 8.12 µg/mL) and HeLa (IC50 = 8.08 µg/mL) cells, respectively. In conclusion, these results provide valuable insight into the potential use of T. leucostomus bioactive extracts in different pharmaceutical applications. © 2023 Deutsche Pharmazeutische Gesellschaft
Annular neutrophilic dermatoses
No full textNeutrophilic dermatoses (NDs) constitute a group of diseases characterized by sterile neutrophilic infiltrations. Many NDs usually present with infiltrated erythematous plaques, nodules, urticarial plaques, or pustules. Lesions may show variability, and atypical presentations may develop among NDs. Annular lesions have been reported in many NDs and may lead to diagnostic problems. Clinical features and histopathologic findings such as localization of the neutrophilic infiltrate, existence of other cell types, and absence of true vasculitis may be helpful to distinguish NDs. Some of these NDs are associated with infections, inflammatory diseases, and malignancies. In most NDs, systemic steroids and dapsone are very effective and usually first choices. Colchicine, antimicrobials such as doxycycline, tetracycline, and sulfapyridine, and other immunosuppressants such as cyclosporin, methotrexate, and mycophenolate mofetil have been used successfully in treating many NDs. Tumor necrosis factor α inhibitors have also been used successfully in treating many NDs. Janus kinase inhibitors are effective in CANDLE (chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature) syndrome, anakinra in neutrophilic urticarial dermatosis, and intravenous immunoglobulin in resistant pyoderma gangrenosum. We discuss the diagnosis and management of NDs that may present with annular lesions. © 2023 Elsevier Inc
HEAVY WORK INVESTMENT AND ITS PREMISES
No full textThere exist some concepts such as workaholism, career satisfaction, work-life balance, work commitment and financial needs, which cause workers to put in more effort at the workplace and subsequently, an increase in their working hours. The main reason why these concepts are called premises is related to the fact that they are defined as factors leading heavy work investment (HWI) in the literature. Overworking has been a concept which could be measured only through time during work until recently, however, it is currently regarded as a concept which covers much more than heavy work as a result of HWI. The present study contributes to the literature by determining the interaction of HWI with its premises. In order to determine whether HWI is formed with effort or via time dimensions and which premises have been effective in its formation, 372 people working in Kars were surveyed on HWI and its premises. The data collected were analysed through Statistical Package for the Social Sciences (SPSS) and Analysis of Moment Structures (AMOS). Due to the limited number of studies on HWI in the literature, the effect of premises on HWI was investigated by developing more than one model. In fact, HWI-Time Commitment (TC) had a negative mediation effect between career satisfaction and premises while HWI-Work Intensity (WI) did not have any effect
Efficacy of keratometric values obtained from Sirius topographer® in nidek axial length-scan® for intraocular lens calculation after penetrating keratoplasty
No full textBackground: To evaluate the accuracy of keratometric values obtained from Scheimpflug (Sirius) topography using Nidek AL-Scan optical biometry (OB) for intraocular lens (IOL) power calculating after penetrating keratoplasty (PK). Methods: Thirty eyes of 26 patients were included in this study. The demographic information, complete ophthalmic examination, IOL calculation technique, and its effect on final refractive results were evaluated. Results: The mean age of the patients was 52.76 ± 16.20 years. The mean K readings using Nidek AL-Scan OB, mean simulated K (SimK) (3mm), and mean pupillary power (MPP) (4.5mm) K readings using Sirius were 41.92 ± 5.05 D, 42.99 ± 5.78 D, and 43.30±6.23 D (p= 0.515). Conclusions: Both devices correctly calculated IOL power after PK; however, Sirius SimK (3mm) gave the lowest mean absolute error (MAE) results and can be safely used for IOL power calculation. © 2022 Elsevier B.V