Optimizing headspace temperature and time sampling for identification of volatile compounds in ground roasted Arabica coffee

Equilibration time and temperature were the factors studied to choose the best conditions for analyzing volatiles in roasted ground Arabica coffee by a static headspace sampling extraction method. Three temperatures of equilibration were studied: 60, 80, and 90 degrees C. A larger quantity of volatile compounds was extracted at 90 degrees C than at 80 or 60 degrees C, although the same qualitative profile was found for each. The extraction of the volatile compounds was studied at seven different equilibration times: 30, 45, 60, 80, 100, 120, and 150 min. The best time of equilibration for headspace analysis of roasted ground Arabica coffee should be selected depending on the chemical class or compound studied. One hundred and twenty-two volatile compounds were identified, including 26 furans, 20 ketones, 20 pyrazines, 9 alcohols, 9 aldehydes, 8 esters, 6 pyrroles, 6 thiophenes, 4 sulfur compounds, 3 benzenic compounds, 2 phenolic compounds, 2 pyridines, 2 thiazoles, 1 oxazole, 1 lactone, 1 alkane, 1 alkene, and 1 acid

Laboratory and numerical experimentation for masonry in compression

In this paper, the initial part of a laboratory and numerical experimental campaign dedicated to historical masonry is described. One leaf masonry panels with regular texture are built in order to simulate a historical material characterised by strong resisting elements and weak mortar joints. Laboratory tests are first dedicated to masonry components and then to the behaviour in compression of masonry panels, which is applied both orthogonal and parallel to bed joints, in order to highlight the orthotropic behaviour of the material. First of all, the mechanical parameters of masonry constituents are calibrated and then a heterogeneous finite element model is introduced and calibrated for reproducing the orthotropic behaviour of masonry, together with the initial elastic response and the initial nonlinear behaviour due to the first level of damage

Nano-HPLC-HRMS analysis to evaluate leptin level in milk samples: A pilot study

Leptin is a 16 kDa lipophilic protein hormone secreted by adipocytes and its most significant function is to inform the brain with negative feedback that regulates food intake. Recently the protein found in human breast milk was related to breast feeding and onset of obesity, and the evidence of a low probability to develop pediatric obesity in children fed with breast milk was also confirmed. Since leptin could have a critical role, its quantitation both in human breast, bovine milk and in infant formula products is interesting. For this reason, we developed an analytical method based on immunoaffinity purification followed by an analysis with nano-High Pressure Liquid Chromatography coupled with High Resolution Mass Spectrometry analyzer (nano-HPLC-HRMS) to identify and quantify leptin in milk samples and performed a pilot study using samples of human breast milk, bovine milk and infant formulas. With an obtained lower limit of quantitation (LLOQ) of 100 ng mL−1 we quantified leptin in human breast milk finding an average of 6.70 ng mL−1. Our results show that leptin was under LLOQ both in bovine milk and in infant formula products. In conclusion, the developed analytical method here described was suitable to quantify leptin in milk samples with a good sensitivity and selectivity, and without the use of radioactive reagents

Augmented reality system for digital rectal examination training and assessment: system validation

Background: Digital rectal examination is a difficult examination to learn and teach because of limited opportunities for practice; however, the main challenge is that students and tutors cannot see the finger when it is palpating the anal canal and prostate gland inside the patients. Objective: This paper presents an augmented reality system to be used with benchtop models commonly available in medical schools with the aim of addressing the problem of lack of visualization. The system enables visualization of the examining finger, as well as of the internal organs when performing digital rectal examinations. Magnetic tracking sensors are used to track the movement of the finger, and a pressure sensor is used to monitor the applied pressure. By overlaying a virtual finger on the real finger and a virtual model on the benchtop model, students can see through the examination and finger maneuvers. Methods: The system was implemented in the Unity game engine (Unity Technologies) and uses a first-generation HoloLens (Microsoft Inc) as an augmented reality device. To evaluate the system, 19 participants (9 clinicians who routinely performed digital rectal examinations and 10 medical students) were asked to use the system and answer 12 questions regarding the usefulness of the system. Results: The system showed the movement of an examining finger in real time with a frame rate of 60 fps on the HoloLens and accurately aligned the virtual and real models with a mean error of 3.9 mm. Users found the movement of the finger was realistic (mean 3.9, SD 1.2); moreover, they found the visualization of the finger and internal organs were useful for teaching, learning, and assessment of digital rectal examinations (finger: mean 4.1, SD 1.1; organs: mean 4.6, SD 0.8), mainly targeting a novice group. Conclusions: The proposed augmented reality system was designed to improve teaching and learning of digital rectal examination skills by providing visualization of the finger and internal organs. The initial user study proved its applicability and usefulness

Determinants of Contraceptive Options among Postpartum Women Attending Selected Health Care Facilities in Nigeria: A Cross-Sectional Study

Introduction: Differences in availability and choices of contraceptive methods among postpartum women have been found to influence their quality of life as the fertility rate is very high, and the contraceptive usage rate persistently remains low in Nigeria. Objectives: This study assessed the determinants of contraceptive options among postpartum women in Nigeria. Methods: Two Local Governments were randomly selected from the four Local Governments. Within these two local governments, five health facilities were selected. A multistage sampling technique was used to select the 240 respondents, while a structured questionnaire was used to collect data. Results: Findings from the study indicated that 81.7% of the respondents have planned to have their current baby, and about 65.4% of the women have resumed sexual activities since delivery. Of those who have resumed sexual activities, the majority, 91.1% did so 6 weeks after delivery. Some form of contraceptive usage was prominent among 59.2% of the respondents, as the most common contraceptive method used was withdrawal (24.8%). Contraceptive prevalence was slightly lower for urban respondents than rural respondents, although the relationship was not significant. Also, there was a statistically significant relationship between the current use of contraceptives and resumption of sexual activities since delivery (p = .001), resumption of menstruation (p = .001), and information received about postpartum family planning (p = 0.013). Conclusion: Findings from this study emphasize the urgent need for enhanced accessibility and availability of contraceptive methods, with a parallel emphasis on targeted interventions and effective communication strategies to promote contraceptive uptake and family planning. Addressing these determinants is vital in improving postpartum women's overall quality of life in the study area

Gluten contamination of canned and dry grain-free commercial pet foods determined by HPLC-HRMS

The aim was to determine the absence of gluten in pet food samples marked as ‘grain-free’ and ‘gluten-free’ diets, to assess the reliability of manufacturer labelling of such products. A total of 15 diets labelled as grain- or gluten-free and 2 commercial diets containing wheat were sampled. An analytical procedure using high-pressure liquid chromatography coupled with mass spectrometry with high power of resolution was developed and applied to determine specific markers of wheat gluten. The results are expressed as mg of wheat flour type ‘00’ present in 1 g of feed. The quantification limit (LOQ) obtained in the flour for ion m/z 894.5043, z = 2, is 4 mg of flour per gram. In 14 out of the 15 samples from a grain- or gluten-free diet the quantifier ion signal was < LOQ, while in 1 out of the 15 samples 10 mg of flour/g feed were measured.Highlights Adverse reaction to gluten in dogs have been documented in certain breeds Gluten is tricky to detect and measure in pet food Contamination of gluten in pet food samples marked as ‘grain-free’ and ‘gluten-free’ diets An analytical procedure was developed using HPLC coupled with HRM

Solar photodegradation of irinotecan in water: optimization and robustness studies by experimental design

Irinotecan, a widely prescribed anticancer drug, is an emerging contaminant of concern that has been detected in various aquatic environments due to ineffective removal by traditional wastewater treatment systems. Solar photodegradation is a viable approach that can effectively eradicate the drug from aqueous systems. In this study, we used the design of experiment (DOE) approach to explore the robustness of irinotecan photodegradation under simulated solar irradiation. A full factorial design, including a star design, was applied to study the effects of three parameters: initial concentration of irinotecan (1.0-9.0 mg/L), pH (5.0-9.0), and irradiance (450-750 W/m(2)). A high-performance liquid chromatography coupled with a high-resolution mass spectrometry (HPLC-HRMS) system was used to determine irinotecan and identify transformation products. The photodegradation of irinotecan followed a pseudo-first order kinetics. In the best-fitted linear model determined by the stepwise model fitting approach, pH was found to have about 100-fold greater effect than either irinotecan concentration or solar irradiance. Under optimal conditions (irradiance of 750 W/m(2), 1.0 mg/L irinotecan concentration, and pH 9.0), more than 98% of irinotecan was degraded in 60 min. With respect to irradiance and irinotecan concentration, the degradation process was robust in the studied range, implying that it may be effectively applied in locations and/or seasons with solar irradiance as low as 450 W/m(2). However, pH needs to be strictly controlled and kept between 7.0 and 9.0 to maintain the degradation process robust. Considerations about the behavior of degradation products were also drawn

High-speed imaging of Strombolian explosions: The ejection velocity of pyroclasts

Explosive volcanic eruptions are defined as the violent ejection of gas and hot fragments from a vent in the Earth's crust. Knowledge of ejection velocity is crucial for understanding and modeling relevant physical processes of an eruption, and yet direct measurements are still a difficult task with largely variable results. Here we apply pioneering high-speed imaging to measure the ejection velocity of pyroclasts from Strombolian explosive eruptions with an unparalleled temporal resolution. Measured supersonic velocities, up to 405 m/s, are twice higher than previously reported for such eruptions. Individual Strombolian explosions include multiple, sub-second-lasting ejection pulses characterized by an exponential decay of velocity. When fitted with an empirical model from shock-tube experiments literature, this decay allows constraining the length of the pressurized gas pockets responsible for the ejection pulses. These results directly impact eruption modeling and related hazard assessment, as well as the interpretation of geophysical signals from monitoring networks

Cattle Segmentation and Contour Detection Based on Solo for Precision Livestock Husbandry

Segmenting objects such as herd of cattle in natural and cluttered images is among the herculean dense prediction tasks of computer vision application to agriculture. To achieve the segmentation goal, we based the segmentation on the model of single objects by locations (SOLO) which is capable of exploiting the contextual cues and segmenting individual cattle by their locations and sizes. For its simple approach to instance segmentation with the use of instance categories, SOLO outperforms Mask R-CNN which uses detect-then-segment approach to predict a mask for each instance of cattle. The model is trained using synchronized stochastic gradient descent (SGD) over GPU to achieve a mAP of 0.94 making it 0.02 higher than the result recorded by the Mask R-CNN model. By using the focal loss, the proposed approach achieved 32.23 ADE on cattle contour detection making its performance better than the Mask R-CNN’s performance