Experiments of convective evaporation of refrigerant R513A in a horizontal stainless-steel tube

Refrigerant R513A represents an interesting solution for the retrofit of conventional high-GWP fluorinated gases, such as R134a, R401A, R401B and R409A for low and medium temperature applications. R513A is an azeotropic mixture (almost zero-temperature glide at any operating pressure) made up of R134a and R1234yf (44% and 56% in mass, respectively), allowing at the same time a very low GWP of 580 and favourable safety characteristics such as no flammability and no toxicity (A1 ASHRAE class). The boiling performance of this blend is scarcely explored and studied in scientific literature, especially in case of commercial tubes typically adopted for refrigeration purposes. For this reason, this paper presents two-phase flow boiling experiments of refrigerant R513A in a 6.00 mm horizontal stainless-steel tube. Heat is provided by means of Joule effect directly on the tube surface, and the peripheral average heat transfer coefficients are obtained by measuring the temperatures at four sides (top, bottom, left and right) of the channel. The effect of the operating conditions is experimented and discussed, by varying the mass flux between 150 and 300 kg/m2 s, saturation temperature between 20 and 50°C and imposed heat flux between 5 and 20 kW/m2. Also, a comparison with the boiling performance of refrigerant R134a is proposed within the same operating conditions. Finally, the assessment of well-known flow boiling prediction methods is presented and discussed

Mental Stress Increases Meal-Induced Symptoms Severity by Sympathetic Hyperactivity and Enhanced Endocrine Response in Patients With Postprandial Distress Syndrome

Background and Aim: Previous data show that psychological stress may alter gastric sensorymotor function. Neuro-hormonal mechanisms underlying this phenomenon in dyspeptic patients remain to be clarified. Aim of the present study is to assess autonomic nervous system activity and hypothalamic-pituitary-adrenal (HPA) axis hormones in response to mental stress before and after meal in dyspeptic patients. Subjects and methods: Fifteen patients with postprandial distress syndrome (PDS) (8 M, 21-40 years) and eight healthy controls (4 M, 19-28 years) underwent electrogastrography (EGG) and gastric emptying study (13C-octanoic acid breath test) using a 480 Kcal solid meal. Heart rate variability assessment (LF/HF ratio) by ECG and CRF, ACTH and cortisol on serum samples collected every 30 minutes for 5 hours were also evaluated. Dyspeptic symptoms (postprandial fullness and early satiety) were scored at same time points by analogue visual scale and expressed as sum of total symptoms scores (TSS). The study protocol, with and without a standardized mental stress (MS) test (serial numeric calculations for ten minutes) before the meal, was repeated in a random order in two different days. Results: Dyspeptic symptoms were present only in patients and were exclusively meal-related. In patients, but not in controls, MS significantly increased symptoms severity (TSS: 738±635 vs 288±301, p<0.05). LF/HF ratio was significantly higher in patients during postprandial period with than without MS (5.38±3.48 vs 2.78±0.92; p<0.05), whereas in controls it remained unmodified. In addition, a significant increase of ACTH postprandial levels after MS in patients (stress 6.63±3.11 pg/ml vs no-stress 3.72±2.07; p<0.05) was found, while in controls no modifications were observed. CRF and cortisol were unmodified both in patients and controls. Gastric emptying rate was delayed in 60 % of patients, but it was not influenced by MS. EGG did not show any modification. Conclusions: In PDS patients, concurrent administration of mental stress and meal increases symptoms severity by inducing enhanced sympathetic activity and increased HPA endocrine output. As the gastric emptying looks not altered, we can assume that these neuro-hormonal responses mainly affect gastric sensitive functio

Xanthan-Based Hydrogel for Stable and Efficient Quasi-Solid Truly Aqueous Dye-Sensitized Solar Cell with Cobalt Mediator

9siAqueous dye-sensitized solar cells (DSSCs) are emerging as a promising alternative to enhance both the lifetime and environmental friendliness of traditional DSSCs. Herein, a cobalt-based, jellified (with xanthan gum) aqueous electrolyte, leading to a valuable efficiency exceeding 4% (VOC = 847 mV, JSC = 6.73 mA cm−2, fill factor =  74%), is reported. Design of experiment is used to precisely and significantly study, at a multivariate level, the effects produced by the Co2+ concentration, Co2+/Co3+ ratio, and xanthan gum amount modifications on the overall photovoltaic parameters of lab-scale solar cells.partially_openopenS. Galliano, F. Bella, M. Bonomo, F. Giordano, M. Grätzel, G. Viscardi, A. Hagfeldt, C. Gerbaldi, C. BaroloGalliano, S.; Bella, F.; Bonomo, M.; Giordano, F.; Grätzel, M.; Viscardi, G.; Hagfeldt, A.; Gerbaldi, C.; Barolo, C

Parasite Load and STRs Genotyping of Toxoplasma gondii Isolates From Mediterranean Mussels ( Mytilus galloprovincialis) in Southern Italy

oxoplasmosis is a zoonotic food-borne disease caused by Toxoplasma gondii, a land-derived protozoan parasite that infects a broad range of terrestrial and aquatic hosts. T. gondii may reach coastal waters via contaminated freshwater runoff and its oocysts may enter into the marine food web. Marine invertebrates as mussels being filter feeders are exposed and may concentrate T. gondii oocysts representing a potential source of infection for animals and humans. The present works investigated the prevalence, parasite burden and genotypes of T. gondii in the Mediterranean mussels (Mytilus galloprovincialis) from southern Italy. We sampled a total of 382 individual Mediterranean mussels from May to August 2018 from seven production sites in the Gulf of Naples (Campania region). An additional sample including 27 farmed Mediterranean mussels was obtained in February 2018 from a mollusk depuration plant in Corigliano Calabro (Calabria region). T. gondii DNA was detected in 43 out of 409 (10.5%) Mediterranean mussels from seven out of eight sampling sites. The number of T. gondii copies/g in the digestive gland ranged from 0.14 to 1.18. Fragment analysis of Short Tandem Repeats (STRs) at 5 microsatellite loci was performed from 10 T. gondii PCR positive samples revealing the presence of five distinct genotypes including one corresponding to type I and four atypical genotypes. These findings suggest potential implications of epidemiological importance for human and animal health because both type I and atypical genotypes could be highly pathogenic

Annexin V C/T-1 polymorphism and pregnancy complications

The \u20131T variant of the annexin V gene, which has been suggested to have a protective role against thrombotic disease, was evaluated in 140 women with pregnancy complications and 317 control women with uncomplicated pregnancies. The presence of the -1 CT or TT genotype did not show a protective effect in normal pregnancies

Using a CO2 Surgical Laser for Piglet Castration to Reduce Pain and Inflammation, and to Improve Wound Healing

The objectives of this preliminary study were to determine the ability of a CO2 surgical laser to 1) reduce pain, 2) reduce inflammation, and 3) improve wound healing of piglets undergoing surgical castration. Two-day old male Yorkshire × Landrace piglets were used and randomly assigned to one of three treatments (n = 10 piglets/treatment group): surgical castration with the CO2 laser, surgical castration with a scalpel, or sham (uncastrated control). Piglets were video recorded in their pens for 1 h pre-procedure and from 0-2, 6-8, and at 24 h post-procedure for behavior scoring. Surgical site images were collected at baseline, 0, 8, 24, 48, 72, 96, 120, 144, and 168 h post-castration for wound healing assessment. Infrared thermography (IRT) images of the surgical site were also taken at baseline, 0, 0.5, 8, and 24 h post-procedure to assess inflammation. Finally, blood was collected from each piglet at baseline and 0.5 h post-castration to assess cortisol levels, prostaglandin E metabolite (PGEM), and pig-major acute phase protein (pig-MAP) concentration. Laser-castrated piglets displayed more pain behav­iors across the observation period than scalpel-castrated piglets (P = 0.049). Laser-castrated piglets also displayed significantly more agonistic behavior than both scalpel-castrated and sham piglets (P = 0.005 and P = 0.036, respectively); yet, laser-castrated piglets had significantly lower temperatures at the site of incision compared to scalpel-castrated piglets (P = 0.0211). There was no significant difference in wound healing or any of the blood parameters assessed between laser-castrated and scalpel-castrated piglets. There was evidence of thermal tissue damage on the scrotum of piglets that were castrated using the CO2 laser. This may have resulted in the unremarkable healing time and the increased pain behavior observed in this study. The surgical laser technique should be refined before conclusions can be made regarding the utility of a CO2 laser for piglet castration

TERAVOLT: Thoracic Cancers International COVID-19 Collaboration.

Prior publications on small subsets of cancer patients infected with SARS CoV-2 have shown an increased risk of mortality compared to the general population. Furthermore, patients with thoracic malignancies are thought to be at particularly high risk given their older age, smoking habits, and pre-existing cardio-pulmonary comorbidities. For this reason, physicians around the world have formed TERAVOLT, a global consortium dedicated to understanding the impact of COVID-19 on patients with thoracic malignancies