467 research outputs found

    Bovine Sperm Sexing Alters Sperm Morphokinetics and Subsequent Early Embryonic Development

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    In artificial insemination the use of sex-sorted bovine sperm results in reduced conception, the causes of which are only partly understood. Therefore, we set out to investigate the effects of sexing on bovine sperm function and early embryonic development. Computer-assisted semen analysis (CASA) of sperm of the same bulls (n = 5), before and after sexing, demonstrated significantly reduced fast (A) and slow (B) progressively motile sperm (p [less than] 0.05) after sexing. Sexed-sperm also revealed significantly less hyperactivated sperm (p [less than] 0.05). As shown by time-lapse videomicroscopy of in vitro produced embryos (n = 360), embryos derived from sexed-sperm displayed significantly increased incidences of arrest at the 4-cell stage (p [less than] 0.05). The relative risk for shrinkage/fusion of blastomeres with subsequent lysis was 1.71 times higher in the embryos derived from sexed-sperm as compared to conventional embryos (p [less than] 0.05) resulting in significantly reduced blastocyst rates (p [less than] 0.001). The relative risk for cleavage was 2.36 times lower in the embryos derived from sex-sorted sperm (p [less than] 0.001). Additionally, sexed-sperm-derived embryos showed reduced survival times (hazard ratio HR = 1.54, p [less than] 0.001) which were bull dependent (p [less than] 0.001). However, the percentage of apoptotic cells was similar to conventional embryos. Furthermore, embryos derived from sexed-sperm were found to reach developmental stages at similar timings as conventional embryos. Our results suggest that reduced conception rates after sexing are due to altered sperm morphokinetics, decreasing the chance of sperm to reach and fertilise the oocyte, and aberrant early embryonic development

    Human-Robot Interaction using VAHR: Virtual Assistant, Human, and Robots in the Loop

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    Robots have become ubiquitous tools in various industries and households, highlighting the importance of human-robot interaction (HRI). This has increased the need for easy and accessible communication between humans and robots. Recent research has focused on the intersection of virtual assistant technology, such as Amazon's Alexa, with robots and its effect on HRI. This paper presents the Virtual Assistant, Human, and Robots in the loop (VAHR) system, which utilizes bidirectional communication to control multiple robots through Alexa. VAHR's performance was evaluated through a human-subjects experiment, comparing objective and subjective metrics of traditional keyboard and mouse interfaces to VAHR. The results showed that VAHR required 41% less Robot Attention Demand and ensured 91% more Fan-out time compared to the standard method. Additionally, VAHR led to a 62.5% improvement in multi-tasking, highlighting the potential for efficient human-robot interaction in physically- and mentally-demanding scenarios. However, subjective metrics revealed a need for human operators to build confidence and trust with this new method of operation.Comment: 7 pages, 7 figure

    Characterization of different DLC and DLN electrodes for biosensor design

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    International audienceDiamond-Like Carbon and Carbon-Like Nanocomposite electrodes, novel materials in the field of biosensors, made with different ratio of sp3/sp2 carbon hybridization or doped with elements such as Ni, Si and W, were characterized electrochemically by cyclic voltammetry and by amperometric measurements towards hydrogen peroxide. SiCAr1 and SiCNi5% were chosen as sensitive transducers for elaboration of amperometric glucose biosensors. Immobilization of glucose oxidase was carried out by cross-linking with glutareldehyde. Measurements were made at a fixed potential + 1.0 V in 40 mM phosphate buffer pH 7.4. SiCAr1 seems to be more sensitive for glucose (0.6875 µA/mM) then SiCNi5% (0.3654 µA/mM). Detections limits were respectively 20 µM and 30 µM. Michaelis-Menten constants for the two electrodes were found around 3 mM. 48% and 79% of the original response for 0.5 mM glucose remained respectively for both electrodes after 10 days

    In vitro evaluation of the color stability and surface roughness of a new composite flow

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    The aim of this study was to evaluate the color stability and the surface roughness of a bulk-fill composite flow (SDR® Plus) by comparison to an ORMOCER-based composite (Ceram.x® Universal SphereTEC?) in order to confirm the validity of using SDR® Plus

    The Quantum Theory of MIMO Markovian Feedback with Diffusive Measurements

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    Feedback control engineers have been interested in MIMO (multiple-input multiple-output) extensions of SISO (single-input single-output) results of various kinds due to its rich mathematical structure and practical applications. An outstanding problem in quantum feedback control is the extension of the SISO theory of Markovian feedback by Wiseman and Milburn [Phys. Rev. Lett. {\bf 70}, 548 (1993)] to multiple inputs and multiple outputs. Here we generalize the SISO homodyne-mediated feedback theory to allow for multiple inputs, multiple outputs, and \emph{arbitrary} diffusive quantum measurements. We thus obtain a MIMO framework which resembles the SISO theory and whose additional mathematical structure is highlighted by the extensive use of vector-operator algebra.Comment: 17 pages, 2 figure

    Patterns of ascending aortic dilatation and predictors of surgical replacement of the aorta: A comparison of bicuspid and tricuspid aortic valve patients over eight years of follow-up

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    Background: Predictors of thoracic aorta growth and early cardiac surgery in patients with bicuspid aortic valve are undefined. Our aim was to identify predictors of ascending aorta dilatation and cardiac surgery in patients with bicuspid aortic valve (BAV). Methods: Forty-one patients with BAV were compared with 165 patients with tricuspid aortic valve (TAV). All patients had LV EF > 50%, normal LV dimensions, and similar degree of aortic root or ascending aorta dilatation at enrollment. Patients with more than mild aortic stenosis or regurgitation were excluded. A CT-scan was available on 76% of the population, and an echocardiogram was repeated every year for a median time of 4 years (range: 2 to 8 years). Patterns of aortic expansion in BAV and TAV groups were analyzed by a mixed-effects longitudinal linear model. In the time-to-event analysis, the primary end point was elective or emergent surgery for aorta replacement. Results: BAV patients were younger, while the TAV group had greater LV wall thickness, arterial hypertension, and dyslipidemia than BAV patients. Growth rate was 0.46 ± 0.04 mm/year, similar in BAV and TAV groups (p = 0.70). Predictors of cardiac surgery were aorta dimensions at baseline (HR 1.23, p = 0.01), severe aortic regurgitation developed during follow-up (HR 3.49, p 0.04), family history of aortic aneurysm (HR 4.16, p 1.73), and history of STEMI (HR 3.64, p < 0.001). Conclusions: Classic baseline risk factors were more commonly observed in TAV aortopathy compared with BAV aortopathy. However, it is reassuring that, though diagnosed with aneurysm on average 10 years earlier and in the absence of arterial hypertension, BAV patients had a relatively low growth rate, similar to patients with a tricuspid valve. Irrespective of aortic valve morphology, patients with a family history of aortic aneurysm, history of coronary artery disease, and those who developed severe aortic regurgitation at follow-up, had the highest chances of being referred for surgery

    Quality of life impact and recovery after ureteroscopy and stent insertion: Insights from daily surveys in STENTS

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    BACKGROUND: Our objective was to describe day-to-day evolution and variations in patient-reported stent-associated symptoms (SAS) in the STudy to Enhance uNderstanding of sTent-associated Symptoms (STENTS), a prospective multicenter observational cohort study, using multiple instruments with conceptual overlap in various domains. METHODS: In a nested cohort of the STENTS study, the initial 40 participants having unilateral ureteroscopy (URS) and stent placement underwent daily assessment of self-reported measures using the Brief Pain Inventory short form, Patient-Reported Outcome Measurement Information System measures for pain severity and pain interference, the Urinary Score of the Ureteral Stent Symptom Questionnaire, and Symptoms of Lower Urinary Tract Dysfunction Research Network Symptom Index. Pain intensity, pain interference, urinary symptoms, and bother were obtained preoperatively, daily until stent removal, and at postoperative day (POD) 30. RESULTS: The median age was 44 years (IQR 29,58), and 53% were female. The size of the dominant stone was 7.5 mm (IQR 5,11), and 50% were located in the kidney. There was consistency among instruments assessing similar concepts. Pain intensity and urinary symptoms increased from baseline to POD 1 with apparent peaks in the first 2 days, remained elevated with stent in situ, and varied widely among individuals. Interference due to pain, and bother due to urinary symptoms, likewise demonstrated high individual variability. CONCLUSIONS: This first study investigating daily SAS allows for a more in-depth look at the lived experience after URS and the impact on quality of life. Different instruments measuring pain intensity, pain interference, and urinary symptoms produced consistent assessments of patients\u27 experiences. The overall daily stability of pain and urinary symptoms after URS was also marked by high patient-level variation, suggesting an opportunity to identify characteristics associated with severe SAS after URS

    Overcoming failure in infrastructure risk governance implementation: large dams journey

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    [EN] There is ample recognition of the risk inherent in our very existence and modes of social organization, with a reasonable expectation that implementing risk governance will result in enhanced resilience as a society. Despite this, risk governance is not a mainstream approach in the infrastructure sector, regardless of the increasing number of peer-reviewed published conceptualizations, mature procedures to support its application, or public calls to cope with systemic risks in our modern societies. This paper aims to offer a different view on the issue of risk governance, with focus in the analysis of the root causes of its relatively low degree of implementation in the infrastructure sector. We later analyze the impact of such essential causes, which we have grouped and labeled as the ontology, the concerns, the anathemas, and the forgotten, in the specific field of large dams. 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