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Fractional delay and fractional doppler estimation and mitigation framework in otfs systems
No full textOrthogonal time-frequency space (OTFS) modulation is fast becoming a popular modulation scheme for high-mobility wireless communication due to its ability to render time-varying channels invariant and sparse. However, due to the limited time duration and frequency bandwidth of the transmitted OTFS signal, the occurrence of fractional delay and Doppler shifts becomes inevitable, causing both inter-delay interference (IDeI) and inter-Doppler interference (IDI). In this paper, an impulse-based channel estimation method is used, which takes advantage of the fact that the pilot impulse is a pulse tone (pulsone). A pulsone maintains its shape despite time delay and Doppler shift operations, as well as being self-dual between time and frequency domains. Exploiting these two features, a low-complexity algorithm is proposed to estimate the fractional delay and fractional Doppler channel. We derive the Cramer-Rao lower bound (CRLB) of the estimated fractional channel and show that the developed estimator is efficient. Then, we provide the computational complexity analysis of the proposed algorithm. After that, we show and stress that the proposed channel estimation scheme is better in terms of the channel normalized mean squared error (NMSE) and the bit-error rate (BER). Lastly, the simulation results are confirmed via real experimental results.Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK
The role of copeptin in viral lower respiratory tract infections in child: a prospective case-control study
No full textBackground: Lower respiratory tract infection (LRTI) is a leading cause of morbidity and mortality among children globally. Copeptin, released by the pituitary gland, serves as a biomarker for various conditions and, as a neuroendocrine stress hormone, is useful in acute conditions. This study aimed to determine the role of copeptin levels in LRTI in children and whether it can reliably predict pneumonia severity. Materials and Methods: This prospective case-control study was performed between April and October 2023. The study included four groups: (i) patients diagnosed with bronchiolitis (Group 1, n=25), (ii) patients diagnosed with mild to moderate pneumonia (Group 2, n=25), (iii) patients diagnosed with severe pneumonia (Group 3, n=25), and (iv) a control group (Group 4, n=26). Results: Copeptin values differed significantly between the groups (p0.586 ng/ml. For the identification of patients with severe pneumonia versus those with mild to moderate pneumonia, copeptin exhibited a sensitivity of 97.9 % and specificity of 94.7 % with a cut-off value of >1.215 ng/ml. The copeptin level exhibited a positive correlation with fibrinogen and FAR levels while demonstrating a negative correlation with albumin levels (r=0.354, ⁎⁎P=0.002; r=0.408, ⁎⁎⁎P<0.001; and r=−0.334, ⁎⁎P=0.003, respectively). Conclusions: Copeptin demonstrates potential as a predictor of disease severity in children with pneumonia. It can also serve as a valuable tool to guide physicians in differentiating between bronchiolitis and pneumonia, as well as in diagnosing severe pneumonia
Orthopaedic patients’ emergency department attendance behavior in relation to weather conditions: temperature, rain, day and time, and regional thursday effect
No full textGreat variation was noticed in emergency department (ED) afflux in relation to daily weather conditions, including difficulties in arranging the correct number of orthopaedic on-calls on the floor. This study aimed to quantify the association between the number of patients referred to the orthopaedic team from the ED and weather conditions, particularly daily temperature and rain. Data were obtained from a large state research hospital’s ED attendance. Weather information for the local area for the year was obtained from the regional meteorological office. Data were evaluated using descriptive statistics, with one-way analysis of variance for the relationship between the day of the week and patient numbers, the Pearson test for correlations between daily ED patient flow and daily temperature and the Spearman correlation test for correlations between daily patient flow and daily rain status. A positive and meaningful correlation existed between daily patient influx and daily temperature, along with a negative correlation between daily patient flow and daily rain. Throughout the year, significantly more patients were referred to the orthopaedic team on Thursdays than on any other day of the week. Patients tended to visit the ED more on warm days and days without rain. These results may help in organising daily, monthly or seasonal on-call orthopaedic team requirements despite the challenges. Incorporating climate forecasts into planning the on-call service might help alleviate the stress on the team
Reasons, associated factors, and attitudes toward breastfeeding mothers' use of complementary medicine products: a study from Türkiye
No full textBackground: The use of Complementary Medicine Products (CMPs) has been increasing worldwide, including among breastfeeding mothers. This study aims to investigate the reasons and associated factors of CMP use among breastfeeding mothers in Turkey, alongside their attitudes and experiences. Methods: A descriptive cross-sectional study was conducted using a self-administered, anonymous online survey between 17 December 2023 and 17 March 2024. Women from diverse regions across Türkiye, aged 18 years or older, with a child aged 36 months or younger, who were currently breastfeeding or had breastfed, were invited to participate in the survey. Results: Among 445 mothers who completed the survey, 334 (75.1%) reported using at least one CMP during breastfeeding, with vitamin D, iron supplements, and fennel being the most frequently used. Educational level, employment status, and being a health worker were found to be factors associated with CMP use during breastfeeding, with those having university or higher education, being employed, or working in healthcare showing higher usage rates. The most common reasons for CMP use were “staying healthy” (60.2%) and “supporting immunity” (59.3%). While 91.9% of mothers perceived at least one CMP they used as beneficial, 14.4% of mothers using CMPs experienced adverse effects with at least one product. Safety perceptions of mothers who used CMP varied, with 45.8% believing CMPs were generally safe during breastfeeding. Among CMP users, doctors were chosen as the most trusted (n = 310, 92.8%) information source. A majority of mothers (85.6%) reported that they would like to receive more information about the safety and effectiveness of CMPs. Conclusions: Breastfeeding mothers often use CMPs to stay healthy and support immunity. While healthcare providers are the most trusted source of information, many women get advice from family, friends, or herbalists, and some use CMPs without any recommendations. This underscores the importance of healthcare providers’ role in guiding mothers on the safe and informed use of both prescribed and self-prescribed CMPs
Cancer-on-chip: a breakthrough organ-on-a-chip technology in cancer cell modeling
No full textCancer remains one of the leading causes of death worldwide. The unclear molecular mechanisms and complex in vivo microenvironment of tumors make it difficult to clarify the nature of cancer and develop effective treatments. Therefore, the development of new methods to effectively treat cancer is urgently needed and of great importance. Organ-on-a-chip (OoC) systems could be the breakthrough technology sought by the pharmaceutical industry to address ever-increasing research and development costs. The past decade has seen significant advances in the spatial modeling of cancer therapeutics related to OoC technology, improving physiological exposition criteria. This article aims to summarize the latest achievements and research results of cancer cell treatment simulated in a 3D microenvironment using OoC technology. To this end, we will first discuss the OoC system in detail and then demonstrate the latest findings of the cancer cell treatment study by Ooc and how this technique can potentially optimize better modeling of the tumor. The prospects of OoC systems in the treatment of cancer cells and their advantages and limitations are also among the other points discussed in this study
Incidence of lymphedema and other complications in patients operated on for gynecological cancer including utilization of two lymph node dissection techniques
No full textBackground: To assess the impact of the lymph node dissection (LND) technique on short- and long-term complications. This retrospective review included patients who underwent hysterectomy, oophorectomy, and pelvic ± para-aortic LND for gynecological malignancies (cervical, endometrial, and ovarian) from 2020 to 2022 in our Gynecological Oncology Surgery clinic. Methods and Results: Among 147 patients who underwent pelvic LND for gynecological malignancy, 48 had procedures involving scissors and 99 had procedures involving unipolar cautery. There was no significant difference in the numbers of extracted pelvic and para-aortic lymph nodes between groups. The extents of LND were comparable between the scissors and unipolar cautery groups (p = 0.945). The scissors group exhibited less fluid drainage between days 2 and 5 postoperatively (1300 [600-3100] vs 1800 [600-3400]; p = 0.038). In terms of primary early and late clinical outcomes, there were no significant differences in lymphocele (16.7% vs 15.2%; p = 0.494) and lymphedema (18.8% vs 17.2%; p = 0.491) rates between groups. Conclusions: After retroperitoneal LND for gynecological malignancy, early complications such as lymphocele and late complications such as lower extremity lymphedema did not significantly differ between procedures using cold scissors and procedures using unipolar cautery
A biomechanical study of locking spongious screws and failure rates are higher than expected in plate fixation
No full textLocking plates have a rapidly growing process especially in the past decades and results are satisfactory especially in the osteoporotic bones compared to non-locking compression plates. There are many forms of failure in the fracture fixation of locking plates, and screw pull-out is one of the main failure reasons. In this study, we aim to investigate pull-out failure in locking plates using locking spongious screws. The pull-out force of an FDA approved locking plate system (LPS) and anonymous locking plate using the single lead head locking spongious screw (LPuLSS) was evaluated in vitro on the PCF-15 and PCF-10 osteoporotic sawbone models. A total of 28 individual plate-bone models were tested and pull-out force was evaluated on a distraction machine. The moment of separation of the screws from the bone blocks was noted. In the first study using PCF15 bone model, in Group 1, the pull-out force has an average of 606.82 N. In Group 2, the pull-out force has an average of 294.15 N. According to these results, Group 1 adhere to the bone model 206.29% more strongly than those in Group 2 (P = 0.025). In the second study using PCF 10, in Group 3, the average pull-out force was 166.50 N and in Group 4 the average was 42.83 N. According to these results, Group 3 adhere to the bone model 388.74% more strongly than those in Group 4 (P = 0.002). Locking plates are mostly used in osteoporotic bones and this study demonstrated that the single lead head locking spongious screws which is currently used worldwide have a serious technical problem which arouses with difference of the thread pitch distances on the body and on the head causes pull-out failure
Established focal therapy-hifu, ire, or cryotherapy-where are we now?-a systematic review and meta-analysis
No full textIntroduction: Focal Therapy (FT) is a treatment option for the treatment of limited volume clinically significant prostate cancer (csPCa). We aim to systematically review outcomes of established FT modalities to assess the contemporary baseline and identify gaps in evidence that will aid in further trial and study design. Methods: We conducted a systematic review and meta-analysis of all primary studies reporting outcomes of FT using cryotherapy, high-intensity focused ultrasound (HIFU), and irreversible electroporation (IRE). We described patient inclusion criteria, selection tools, treatment parameters, and surveillance protocols, and pooled overall survival (OS), cancer-specific survival (CSS), metastasis-free survival (MFS), biochemical progression (BP), biopsy, secondary treatment, sexual, and urinary function outcomes. Composite failure was defined as salvage whole gland ablation, radical treatment, hormonal therapy or transition to watchful waiting. Synthesis: We identified 49 unique cohorts of men undergoing FT between 2008 and 2024 (21 cryotherapy, 20 HIFU, and 8 IRE). Median follow-up ranged from 6 to 63 months. Pooled OS was 98.0%, CSS 99.3%, and MFS 98.5%. Pooled BP was 9.4%/year. Biopsy was mandated post-FT within 24 months in 36/49 (73.5%) cohorts, with pooled csPCa (GG ≥ 2) rates of 22.2% overall, 8.9% infield, and 12.3% outfield. The pooled rate of secondary FT was 5.0%, radical treatment 10.5%, and composite failure 14.1%. Of 35 studies reporting sexual function, 45.7% reported a low, 48.6% moderate, and 5.7% severe impact. For 34 cohorts reporting urinary function, 97.1% reported a low impact. No differences were noted between cryotherapy, HIFU, or IRE in any of the outcomes. Conclusion: FT with cryotherapy, HIFU, and IRE is associated with good short-intermediate term oncological and functional outcomes. However, outcome reporting is heterogeneous and often incomplete. Long-term follow-up and standardized reporting are required to better define and report FT outcomes.National Medical Research Council, Singapor
Curcumin-loaded emulsome nanoparticles induces apoptosis through p53 signaling pathway in pancreatic cancer cell line panc-1
No full textPancreatic cancer is a global health problem with a poor prognosis, limited treatment options and low survival rates of patients. Thus, the exploration of novel treatment approaches is crucial. Curcumin shows promise in pancreatic cancer. Curcumin has anticancer properties promoting apoptosis through the p53 pathway. However, adverse effects and low bioavailability are curcumin's main drawbacks and its delivery by nanoparticles could improve its effectiveness as a treatment option. Curcumin-loaded emulsome nanoparticles (CurEm) have shown promise in colorectal, hepatocellular, and prostate cancers. This study aims to evaluate the anticancer potential of CurEm in pancreatic cancer cell line PANC-1. The cytotoxic effects of CurEm on PANC-1 cells show cytotoxicity in dose and time-dependent manner. The selected dose 30 μM CurEm resulted spheroidal morphology in PANC-1 cells and colony forming and scratch assay conducted demonstrated significant growth inhibition and decrease in migration ability, respectively. Cell cycle analysis shows that CurEm induces G2/M arrest in PANC-1 cells. CurEm-treated PANC-1 cells showed a significant increase in p53 and Caspase 3 genes, while a significant decrease in Bcl-2 genes compared to untreated group. Western blot results showed parallel results to qPCR analysis for Bcl-2 protein levels. Interestingly, we saw low p53 protein levels in CurEm-treated PANC-1 cells. These findings shed light on the potential of CurEm as an effective and stable therapeutic approach for pancreatic cancer
Artificial intelligence meets the world experts; updates and novel therapies in autoimmunity - the 14th international congress on autoimmunity 2024 (AUTO14), Ljubljana
No full textThe bi-annual international congress on autoimmunity is a huge opportunity for the medical community to discuss the latest updates in the field. During the 14th congress 2024 (AUTO14) in Ljubljana, artificial intelligence (AI) occupied special attention due to its recent and ongoing unequivocal role in various medical fields including autoimmunity. For instance, through a challenging debate between world-experts and the most popular AI bot used (ChatGPT), several clinical cases including a case of vasculitis were discussed in the plenary sessions. ChatGPT agreed with the clinical decisions made by the experts nevertheless, the bot added additional aspects related to the specific case. In this regard, ChatGPT emphasized the need for osteoporosis prophylaxis in a patient planned to be treated with systemic steroids for a long time. Furthermore, AUTO14 included the newest updates on most autoimmune disorders, distributed among tens of sessions. Among others, infection and autoimmunity, the sequalae of the pandemic of COVID-19, as well as COVID-19 vaccines were discussed as well. Due to the high numbers of the works presented, and for ensuring that important updates are not missed; we divided our paper into sections. The subtitles throughout the paper correspond to different sessions of the congress, all presenting new updates in the field. A figure aiding in navigating throughout the paper was also provided