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Generatect: text-conditional generation of 3d chest ct volumes
No full textText-conditional medical image generation is vital for radiology, augmenting small datasets, preserving data privacy, and enabling patient-specific modeling. However, its applications in 3D medical imaging, such as CT and MRI, which are crucial for critical care, remain unexplored. In this paper, we introduce GenerateCT, the first approach to generating 3D medical imaging conditioned on free-form medical text prompts. GenerateCT incorporates a text encoder and three key components: a novel causal vision transformer for encoding 3D CT volumes, a text-image transformer for aligning CT and text tokens, and a text-conditional super-resolution diffusion model. Without directly comparable methods in 3D medical imaging, we benchmarked GenerateCT against cutting-edge methods, demonstrating its superiority across all key metrics. Importantly, we explored GenerateCT’s clinical applications by evaluating its utility in a multi-abnormality classification task. First, we established a baseline by training a multi-abnormality classifier on our real dataset. To further assess the model’s generalization to external datasets and its performance with unseen prompts in a zero-shot scenario, we employed an external dataset to train the classifier, setting an additional benchmark. We conducted two experiments in which we doubled the training datasets by synthesizing an equal number of volumes for each set using GenerateCT. The first experiment demonstrated an 11% improvement in the AP score when training the classifier jointly on real and generated volumes. The second experiment showed a 7% improvement when training on both real and generated volumes based on unseen prompts. Moreover, GenerateCT enables the scaling of synthetic training datasets to arbitrary sizes. As an example, we generated 100,000 3D CT volumes, fivefold the number in our real dataset, and trained the classifier exclusively on these synthetic volumes. Impressively, this classifier surpassed the performance of the one trained on all available real data by a margin of 8%. Lastly, domain experts evaluated the generated volumes, confirming a high degree of alignment with the text prompts. Access our code, model weights, training data, and generated data at https://github.com/ibrahimethemhamamci/GenerateCT.Helmut Horten Foundatio
Nuclear energy utilization and the expectations of emission-reduction gains: empirical evidence from economic trajectory of selected utilizing states
No full textAs the global quest for clean energy grows, the environmentally friendly nature of nuclear energy as a potential non-fossil energy source is generating interest around the world. Therefore, we examine whether nuclear energy utilization has significantly driven carbon emission reduction among the utilizing states. Empirical analyses were conducted using second-generation techniques. The analyses conducted also incorporated testing the EKC theory, as well as examining the effects of natural resources and economic growth on emissions in the sample countries. The empirical analyses cover data from 2000 to 2020 for a total of 27 nuclear energy-using countries as obtained from the Statistical Review of World Energy (Bp, 2021). The findings show that neither the use of nuclear energy nor natural resources significantly reduces carbon emissions across the countries. Additionally, the EKC hypothesis of reduction in emission levels as income expands beyond a certain threshold does not hold for the countries. Moreover, the causality analysis shows that there is a one-way causality from emissions to nuclear energy use. These findings thus highlight the need for more research on how to minimize the indirect carbon footprint that is associated with nuclear energy utilization
Vnotes as a salvage method for adnexectomy and high uterosacral ligament suspension after vaginal hysterectomy under epidural anesthesia: a feasibility and safety study
No full textObjective: To evaluate the feasibility and safety of transvaginal natural orifice transluminal endoscopic surgery (vNOTES) for performing adnexectomy and high uterosacral ligament suspension (HUSLS) after vaginal hysterectomy (VH) under epidural anesthesia. Method: This was a retrospective case series of 42 women who underwent VH for stage II or greater apical prolapse according to pelvic organ prolapse quantification (POP-Q); however, adnexectomy could not performed and replace the vNOTES technique. The procedure continued with vNOTES adnexectomy and bilateral HUSLS under epidural anesthesia. Patient demographics, operation outcomes, and short-term and long-term complications were analyzed. Patients’ quality of life was assessed with the Pelvic Floor Distress Inventory-20 (PFDI-20) at the 24-month visit. Results: vNOTES procedures were performed successfully under epidural anesthesia in all patients. One patient was converted to general anesthesia due to ureter injury. The mean age of the patients was 54 years. The mean operating time for all procedures was 55 min (range 42–122). The mean blood loss was 90 ml. All patients ambulated 6 h later. The mean pain score 24 h later according to the visual analog scale (VAS) was 2 (range 0–5). The median length of hospital stay was 1 night (range 1–3). There were no complications or morbidities during the postoperative period. Each POP-Q score significantly improved at the 6-month visit (p < 0.05). While the preoperative mean total PFDI-20 score was 20.4 ± 6.6, it significantly decreased to 8 ± 1.2 24 months later (p < 0.05). Conclusion: The vNOTES technique is a good option when adnexectomy can not be performed after VH. The procedure can be completed safely under epidural anesthesia by performing HUSLS for apical support along with adnexectomy. In this way, patients combine the advantages of scarless minimally invasive surgery with the advantages of epidural anesthesia. Introductıon
Comparison of the effects of orthoses on hallux valgus angle and plantar pressure in individuals with hallux valgus
No full textBackground:Hallux valgus (HV) is a condition characterized by the lateral deviation of the first phalanx and medial deviation of the first metatarsal, leading to subluxation of the first metatarsophalangeal joint. Various orthotic applications are employed in the treatment of HV deformity. This study aimed to compare the effects of a toe separator (TS) and dynamic orthosis (DO) on hallux valgus angle (HVA), plantar pressure (PP), and quality of life (QoL).Methods:Thirty individuals aged between 18 and 65 years who had mild to moderate HV deformity were included in our study. Participants were randomized into TS and DO groups. Pretest and post-test evaluations at 4 weeks included goniometric measurement for HVA, PP measurement using the Sensor Medica device, QoL assessment using the American Orthopaedic Foot & Ankle Society-Hallux MTP-IP Scale and Manchester-Oxford Foot Questionnaire, and numerical evaluation scale for orthosis satisfaction.Results:No statistically significant changes were observed in HVA measurements (p > 0.05). In the DO group, significant differences were observed in PP assessment for right rearfoot loading (p = 0.048) and total average pressure measurement of the right foot (p = 0.025). QoL assessments were observed significant differences in the DO group compared with the TS group (p < 0.05).Conclusions:After a 4-week period of wearing the TS and DO orthoses, no change in HVA was observed. In the DO group, a more balanced load distribution between the right and left foot (50.2% left, 49.8% right) and a more pronounced effect in reducing deformity-related pain and improving QoL by increasing functionality were noted
520 nm and 660 nm light-emitting diodes modulates pancreatic development and beta cell functions in zebrafish embryos
No full textGreen and Red LEDs increase insulin production, but their comparative effects on pancreatic and beta cell development are unclear. Zebrafish embryos were divided into three groups: Control (n = 60), Green (G) (n = 60), and Red (R) (n = 60), then irradiated for three days (14 hours/day) with 0.5 W/cm2 G (λpeak = 520 nm, 180 mA) and R (λpeak = 660 nm, 210 mA). At the end of 72 h, pancreatic and beta cells, circadian rhythm, and oxidative stress gene were analyzed using RT-PCR. Malondialdehyde, nitric oxide, superoxide dismutase, and glutathione levels were also evaluated. In the Red group, pancreatic area increased by ~97.13% compared to the Control group and by approximately ~62.16% compared to the G group (both p < 0.0001), and no significant difference in beta cell area (p = 0.964). G group insulin expression increased 2.31-fold compared to R group (p < 0.0001). Red LED treatment increased MDA levels (p < 0.001), oxidative stress (fth1b, nqo1) (p < 0.0001), and per1b during the photophase (p < 0.0001) compared to G group. R LED treatment increases oxidative stress and disrupts circadian rhythm, leading to reduced insulin secretion. The positive effects of G LED treatment have potential for metabolic syndrome, diabetes, and pancreatic diseases.Scientific and Technological Research Council of Turkiye (TUBITAK) ; Scientific Research Projects Foundation (BAP) of the Marmara Universit
Generalization of ρ-ideals associated with an m-system and a special radical class
No full textLet phi not equal S subset of R be an m-system of a ring R, and let. be a special radical. This study introduces the concept of S-rho-ideals in noncommutative rings. This notion extends the previously studied rho-ideals and can also be seen as a generalization of the right S-prime ideals. We show how some properties associated with rho-ideals have evolved into results within these generalizations. Relationships between S-rho-ideals and other types of ideals like rho-ideals, right S-prime ideals, and S-finite ideals are shown. We show the behaviour of this notion in related rings. The construction of (S boxed plus M)-rho-ideals in idealization rings is presented for an R- R-bimodule M. Additionally, we introduce S-P-ideals using Baer-McCoy radical P and examine their properties
Hippocampal connectivity dynamics and volumetric alterations predict cognitive status in migraine: a resting-state fMRI study
No full textThe etiology of cognitive decline linked to migraine remains unclear, with a growing recurrence rate and potential increased dementia risk among sufferers. Cognitive dysfunction has recently gained attention as a significant problem among migraine sufferers that can be related to alterations in hippocampal function and structure. This study explores hippocampal subfield connectivity and volume changes in migraine patients. We recruited 90 individuals from Alanya University's Neurology Department, including 49 migraine patients and 41 controls, for functional and anatomical imaging. Using the CONN toolbox and FreeSurfer, we assessed functional connectivity and subfield volumes, respectively. Montreal Cognitive Assessment (MOCA) was used to assess cognition in the entire sample. As a result, migraine patients exhibited significantly lower MOCA scores compared to controls (p<.001). Also, we found significant differences in hippocampal subfields between migraine patients and control groups in terms of functional connectivity after adjusting for years of education; here we showed that the left CA3 showed higher connectivity with right MFG and right occipitolateral cortex. Furthermore, the connectivity of left fimbria with the left temporal lobe and hippocampus and the connectivity of the right hippocampal-tail with right insula, heschl's gyrus, and frontorbital cortex were lower in the migraineurs. Additionally, volumes of specific hippocampal subfields were significantly lower in the migraineurs (whole hippocampus p = 0.004, whole hippocampus head p = 0.003, right CA1 head p = 0.006, and right HATA p = 0.005) compared to controls. In conclusion, these findings indicate that migraine-associated cognitive impairment involves significant functional and structural brain changes, particularly in the hippocampus, which may heighten dementia risk. This pioneering study unveils critical hippocampal alterations linked to cognitive function in migraine sufferers, underscoring the potential for these changes to impact dementia development
The effect of oral water and ice popsicle exposure on the management of thirst in the immediate postoperative period
No full textPurpose: Thirst is a high-incidence condition that causes patients to experience problems in the early postoperative period in the postanesthesia care unit (PACU). The study was conducted to determine the effect of oral water and ice application in managing early postoperative thirst. Design: Randomized controlled trial. Methods: The study was conducted between January and April 2017 with 150 patients who were transferred from the operating room of a university hospital to the PACU and met the research criteria. The patients were divided into treatment (water group = 50, ice group = 50) and control (n = 50) groups. Patients in the intervention group received oral water/ice application after admission to the PACU after surgery. Patients in the control group received routine treatment and care. Findings: In intragroup comparisons before and after the application, there was a statistically significant decrease in thirst, dry mouth, dry throat, and difficulty in swallowing in the water and ice groups (P .05). Conclusions: Postoperative oral water/ice application was an effective and safe nursing intervention to reduce thirst, dry mouth, dry throat, and difficulty in swallowing. Ice application was more effective
Boosting the electrochemical performance of ternary metal oxide anode in lithium-ion batteries via biomass-derived carbon nanodot modification
No full textTransition metal oxides deliver high capacity but demonstrate a short cycle life when they are utilized as the anode active material in lithium ion batteries. This study offers an innovative solution to this problem by designing new composite materials in which, the modification of ternary transition metal oxide by carbon nanodots is utilized. Carbon nanodots isolated from Phoenix Dactylifera L. seeds are used by the authors for the first time to process hydrothermally produced zinc nickel ferrite powders. Subsequently, the combination is treated in a rotating evaporator to provide a uniform mix. Then, the finished product is heated to 600 °C in air. Once these powders (ternary metal oxide from hydrothermal (Sample 1) and C-dot modified ternary metal oxide (Sample 2)) are utilized as anode active materials, Sample 2 performs 1224.74 mAh g−1 at the 200th cycles upon the application of 0.1 mA g−1 current load in cycling. Sample 2 tested under various current loads ranging from 0.1 to 2 A g−1 it delivers 1229.08 mAh g−1 at the 270th cycle. It is thus demonstrated that through careful material selection and process design it is possible to synthesize sustainable anode active materials that could withstand high current loads, with long cycle life. It is anticipated that the encouraging outcomes of this study would open up new vistas to design sustainable composite anode active materials.Istanbul Medipol University ; Istanbul Technical Universit
Risk factors in addition to short and long-term outcomes with thin catheter surfactant administration failure in preterm infants: a retrospective analysis
No full textObjective: To evaluate the incidence of thin catheter surfactant administration (TCA) failure and compare short and long-term neonatal outcomes who failed TCA or did not. Design: Single-center retrospective cohort study. Infants between 25 and 30 weeks of gestational age with respiratory distress syndrome and receiving 200 mg/kg poractant alfa via thin catheter administration were included. TCA failure was defined as the need for early mechanical ventilation (< 72 h). Infants were divided into two groups those who failed TCA or those who did not. Results: The TCA failure rate was 24.6%. Initial oxygen requirement (0.39% vs. 0.36%) and the number of small for gestational age infants were significantly higher in the TCA failure group (15% vs. 7.9%). Infants who failed TCA had a higher pneumothorax (6.7% vs. 1.1%, p = 0.03), BPD (15% vs.5.5%, p = 0.02), late-onset sepsis (36.7% vs. 18%, p = 0.04), retinopathy of prematurity rates (11.7% vs. 3.3%, p = 0.02) and an increased duration of respiratory support. However, Bayley Scales of Infant Development II scores were comparable between groups at 18 and 26 months of corrected age. Conclusion: Infants who fail TCA are at increased risk for short-term complications despite favourable long-term neurodevelopmental outcomes. Identifying infants at risk of TCA failure may help early prevention of morbidities and individualise their management