65 research outputs found

    Who discovered the binary system and arithmetic? Did Leibniz plagiarize Caramuel?

    Get PDF
    Gottfried Wilhelm Leibniz (1646–1716) is the self-proclaimed inventor of the binary system and is considered as such by most historians of mathematics and/or mathematicians. Really though, we owe the groundwork of today’s computing not to Leibniz but to the Englishman Thomas Harriot and the Spaniard Juan Caramuel de Lobkowitz (1606–1682), whom Leibniz plagiarized. This plagiarism has been identified on the basis of several facts: Caramuel’s work on the binary system is earlier than Leibniz’s, Leibniz was acquainted—both directly and indirectly—with Caramuel’s work and Leibniz had a natural tendency to plagiarize scientific works.2017-1

    Light-induced ferroelectric modulation of p-n homojunctions in monolayer MoS2

    Get PDF
    The association of 2D materials and ferroelectrics offers a promisingapproach to tune the optoelectronic properties of atomically thin TransitionMetal Dichalcogenides (TMDs). In this work, the combined effect offerroelectricity and light on the optoelectronic properties of monolayer(1L)-MoS2 deposited on periodically poled lithium niobate crystals is explored.Using scanning micro-photoluminescence, the effect of excitation intensity,scanning direction, and domain walls on the 1L-MoS2 photoluminescenceproperties is analyzed, offering insights into charge modulation of MoS2 . Thefindings unveil a photoinduced charging process dependent on theferroelectric domain orientation, in which light induces charge generation andtransfer at the monolayer-substrate interface. This highlights the substantialrole of light excitation in ferroelectrically-driven electrostatic doping in MoS 2 .Additionally, the work provides insights into the effect of the strong,nanometrically confined electric fields on LiNbO3 domain wall surfaces,demonstrating precise control over charge carriers in MoS2 , and enabling thecreation of deterministic p-n homojunctions with exceptional precision. Theresults suggest prospects for novel optoelectronic and photonic applicationinvolving monolayer TMDs by combining light-matter interaction processesand the surface selectivity provided by ferroelectric domain structuresPID2019-108257GB-I00, PID2022-137444NB-I00, TED2021-132219A-I00, PID2022-142331NB-I00, PID2019-108257GB-I00, PID2019-106268GB-C31, PID2022-138908NB-C3

    Experimental study of hybrid-knife endoscopic submucosal dissection (ESD) versus standard ESD in a Western country

    Get PDF
    BACKGROUND: Endoscopic submucosal dissection (ESD) is an effective but time-consuming treatment for early neoplasia that requires a high level of expertise. OBJECTIVE: The objective of this study was to assess the efficacy and learning curve of gastric ESD with a hybrid knife with high pressure water jet and to compare with standard ESD. MATERIAL AND METHODS: We performed a prospective non survival animal study comparing hybrid-knife and standard gastric ESD. Variables recorded were: Number of en-bloc ESD, number of ESD with all marks included (R0), size of specimens, time and speed of dissection and adverse events. Ten endoscopists performed a total of 50 gastric ESD (30 hybrid-knife and 20 standard). RESULTS: Forty-six (92 %) ESD were en-bloc and 25 (50 %) R0 (hybrid-knife: n = 13, 44 %; standard: n = 16, 80 %; p = 0.04). Hybrid-knife ESD was faster than standard (time: 44.6 +/- 21.4 minutes vs. 68.7 +/- 33.5 minutes; p = 0.009 and velocity: 20.8 +/- 9.2 mm(2)/min vs. 14.3 +/- 9.3 mm(2)/min (p = 0.079). Adverse events were not different. There was no change in speed with any of two techniques (hybrid-knife: From 20.33 +/- 15.68 to 28.18 +/- 20.07 mm(2)/min; p = 0.615 and standard: From 6.4 +/- 0.3 to 19.48 +/- 19.21 mm(2)/min; p = 0.607). The learning curve showed a significant improvement in R0 rate in the hybrid-knife group (from 30 % to 100 %). CONCLUSION: despite the initial performance of hybrid-knife ESD is worse than standard ESD, the learning curve with hybrid knife ESD is short and is associated with a rapid improvement. The introduction of new tools to facilitate ESD should be implemented with caution in order to avoid a negative impact on the results

    Clinical validation of risk scoring systems to predict risk of delayed bleeding after EMR of large colorectal lesions

    Get PDF
    [Background and Aims]: The Endoscopic Resection Group of the Spanish Society of Endoscopy (GSEED-RE) model and the Australian Colonic Endoscopic Resection (ACER) model were proposed to predict delayed bleeding (DB) after EMR of large superficial colorectal lesions, but neither has been validated. We validated and updated these models.[Methods]: A multicenter cohort study was performed in patients with nonpedunculated lesions ≥20 mm removed by EMR. We assessed the discrimination and calibration of the GSEED-RE and ACER models. Difficulty performing EMR was subjectively categorized as low, medium, or high. We created a new model, including factors associated with DB in 3 cohort studies.[Results]: DB occurred in 45 of 1034 EMRs (4.5%); it was associated with proximal location (odds ratio [OR], 2.84; 95% confidence interval [CI], 1.31-6.16), antiplatelet agents (OR, 2.51; 95% CI, .99-6.34) or anticoagulants (OR, 4.54; 95% CI, 2.14-9.63), difficulty of EMR (OR, 3.23; 95% CI, 1.41-7.40), and comorbidity (OR, 2.11; 95% CI, .99-4.47). The GSEED-RE and ACER models did not accurately predict DB. Re-estimation and recalibration yielded acceptable results (GSEED-RE area under the curve [AUC], .64 [95% CI, .54-.74]; ACER AUC, .65 [95% CI, .57-.73]). We used lesion size, proximal location, comorbidity, and antiplatelet or anticoagulant therapy to generate a new model, the GSEED-RE2, which achieved higher AUC values (.69-.73; 95% CI, .59-.80) and exhibited lower susceptibility to changes among datasets.[Conclusions]: The updated GSEED-RE and ACER models achieved acceptable prediction levels of DB. The GSEED-RE2 model may achieve better prediction results and could be used to guide the management of patients after validation by other external groups. (Clinical trial registration number: NCT 03050333.)Research support for this study was received from “La Caixa/Caja Navarra” Foundation (ID 100010434;project PR15/11100006)

    Serum CD26 is related to histopathological polyp traits and behaves as a marker for colorectal cancer and advanced adenomas

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Serum CD26 (sCD26) levels were previously found diminished in colorectal cancer (CRC) patients compared to healthy donors, suggesting its potential utility for early diagnosis. Therefore we aimed to estimate the utility of the sCD26 as a biomarker for CRC and advanced adenomas in a high-risk group of patients. The relationship of this molecule with polyp characteristics was also addressed.</p> <p>Methods</p> <p>sCD26 levels were measured by ELISA in 299 symptomatic and asymptomatic patients who had undergone a colonoscopy. Patients were diagnosed as having no colorectal pathology, non-inflammatory or inflammatory bowel disease, polyps (hyperplastic, non-advanced and advanced adenomas) or CRC.</p> <p>Results</p> <p>At a 460 ng/mL cut-off, the sCD26 has a sensitivity and specificity of 81.8% (95% CI, 64.5-93.0%) and 72.3% (95% CI, 65.0-77.2%) for CRC regarding no or benign colorectal pathology. Clinicopathological analysis of polyps showed a relationship between the sCD26 and the grade of dysplasia and the presence of advanced adenomas. Hence, a 58.0% (95% CI, 46.5-68.9%) sensitivity detecting CRC and advanced adenomas was obtained, with a specificity of 75.5% (95% CI, 68.5-81.0%).</p> <p>Conclusions</p> <p>Our preliminary results show that measurement of the sCD26 is a non-invasive and reasonably sensitive assay, which could be combined with others such as the faecal occult blood test for the early diagnosis and screening of CRC and advanced adenomas. Additional comparative studies in average-risk populations are necessary.</p
    corecore