Sulfonic acid coating of refractory sand for three-dimensional printing applications

Abstract: Rapid sand casting processes by additive manufacturing are predominantly based on furfuryl alcohol resin bonded sand catalysed with sulfonic acid. The prior coating of the refractory sand with sulfonic acid is a crucial process to ensure the suitability of the sand for threedimensional printing applications. The present paper investigated the sulfonic acid coating process of a local silica sand, which was found to have potential for three-dimensional printing applications in previous studies. Experimental conditions included sulfonic acid catalyst addition and mixing time. Coated sand was assessed for flowability and mechanical properties of test specimens produced by three-dimensional printing using a Voxeljet VX 1000. The optimum catalyst addition ranged between 0.3 and 0.6% yielding to transverse strength in the order of 110 to 165 KN/m2 and tensile strength ranging from 710 to 770 KN/m2

The Tomato Strikes Back: Plant Response to Environmental Stress

Introduction Tomato is an important vegetable. Its production is threatened due to altered weather patterns which increase environmental stressors such as flooding1, 2 and herbivory3 to crops. Plants respond in many ways. Stressed plants strike back to environmental stress by altering their chemistry4: Volatile Organic Compounds (VOCs) emissions Defensive secondary metabolites2 Stress induced physiological changes in plants impact growth and development of insects. This study is broken into two experiments: The plant response to flooding stress The insect performance on flooded plant

Cardiac myosin binding protein-C variants in paediatric-onset hypertrophic cardiomyopathy: natural history and clinical outcomes

Background: Variants in the cardiac myosin-binding protein C gene (MYBPC3) are a common cause of hypertrophic cardiomyopathy (HCM) in adults and have been associated with late-onset disease, but there are limited data on their role in paediatric-onset HCM. The objective of this study was to describe natural history and clinical outcomes in a large cohort of children with HCM and pathogenic/likely pathogenic (P/LP) MYBPC3 variants. / Methods and results: Longitudinal data from 62 consecutive patients diagnosed with HCM under 18 years of age and carrying at least one P/LP MYBPC3 variant were collected from a single specialist referral centre. The primary patient outcome was a major adverse cardiac event (MACE). Median age at diagnosis was 10 (IQR: 2–14) years, with 12 patients (19.4%) diagnosed in infancy. Forty-seven (75%) were boy and 31 (50%) were probands. Median length of follow-up was 3.1 (IQR: 1.6–6.9) years. Nine patients (14.5%) experienced an MACE during follow-up and five (8%) died. Twenty patients (32.3%) had evidence of ventricular arrhythmia, including 6 patients (9.7%) presenting with out-of-hospital cardiac arrest. Five-year freedom from MACE for those with a single or two MYBPC3 variants was 95.2% (95% CI: 78.6% to 98.5%) and 68.4% (95% CI: 40.6% to 88.9%), respectively (HR 4.65, 95% CI: 1.16 to 18.66, p=0.03). / Conclusions: MYBPC3 variants can cause childhood-onset disease, which is frequently associated with life-threatening ventricular arrhythmia. Clinical outcomes in this cohort vary substantially from aetiologically and genetically mixed paediatric HCM cohorts described previously, highlighting the importance of identifying specific genetic subtypes for clinical management of childhood HCM

Cholécystectomies Laparoscopiques Pour Cholécystite Aigue Lithiasique Versus Lithiase Vésiculaire Symptomatique

Introduction: The aim of this work was to highlight the therapeutic and prognostic difficulties between a laparoscopic cholecystectomy for acute gallstone cholecystitis (CAL) and uncomplicated symptomatic vesicular lithiasis (LVS) as well as the reasons for conversion to laparotomy. Patients and Methods: This was a prospective comparative and analytic study over 18 months. Patients admitted and operated for CAL or LVS in the A Surgery Department of the National Hospital of Niamey (HNN) were included. Results: The study involved 61 patients divided into two groups. Group 1 (30 patients) corresponding to patients operated for CAL, group 2 (31 patients) corresponding to patients operated for LVS. Laparoscopic cholecystectomy accounted for 61% of all cholecystectomies performed and 1.45% of surgical activity during the same period. The average age in group 1 was 43.7 years with extremes of 14 and 61 years. In group 2, the average age was 38.9 years with extremes ranging from 12 to 55 years. Women were predominantly represented with 63.3% and 96.7% respectively for groups 1 and 2. Patients were overweight in 9 cases for group 1 (30% of cases) and 12 cases in group 2 (38%), 7% of cases). Hepatic colic was the main sign of appeal in all patients in both groups. In group 1; 26 out of 30 cases or 86.7% of cases had leukocytosis, whereas in group 2, leukocytosis was normal in 30 cases, ie 96.8% of cases. Accessibility of the vesicle was difficult in 73.3% of cases in group 1 against 22.6% of cases in group 2. The vesicle was distended and necrotic in groups 1 in 76.7% and 10 respectively. % of cases. On the other hand, in 25.8% of cases, the vesicle was distended and without any necrosis in group 2. The rate of conversion to laparotomy was 6.55% (4 cases) and exclusively concerned group 1. Operative follow-up immediate outcomes were simple in 98.34% of cases. The complications involved 2 patients in group 1 (1.66% of the total), including parietal suppuration and biliary leakage. Mean operative time was 68.7 min in group 1 versus 41.6 min in group 2. Mean duration of hospitalization was 4.3 days with extremes between 2 and 10 days in group 1 versus1,7 days with extremes ranging from 1 to 7 days in group 2. Mortality was zero. Conclusion: In recent years, laparoscopic surgery has made remarkable progress in Niger. Laparoscopic cholecystectomy seems to be more difficult to perform with significant morbidity in the case of CAL than LVS. The risk of per and postoperative complications can be estimated from the clinical data (acute cholecystitis or symptomatic vesicular lithiasis) and the surgeon's experience. In a cholecystectomy that lasts more than 2 hours, the cumulative risk of complications is highe

Retinoic acid regulates avian lung branching through a molecular network

Retinoic acid (RA) is of major importance during vertebrate embryonic development and its levels need to be strictly regulated otherwise congenital malformations will develop. Through the action of specific nuclear receptors, named RAR/RXR, RA regulates the expression of genes that eventually influence proliferation and tissue patterning. RA has been described as crucial for different stages of mammalian lung morphogenesis, and as part of a complex molecular network that contributes to precise organogenesis; nonetheless, nothing is known about its role in avian lung development. The current report characterizes, for the first time, the expression pattern of RA signaling members (stra6, raldh2, raldh3, cyp26a1, rar alpha, and rar beta) and potential RA downstream targets (sox2, sox9, meis1, meis2, tgf beta 2, and id2) by in situ hybridization. In the attempt of unveiling the role of RA in chick lung branching, in vitro lung explants were performed. Supplementation studies revealed that RA stimulates lung branching in a dose-dependent manner. Moreover, the expression levels of cyp26a1, sox2, sox9, rar beta, meis2, hoxb5, tgf beta 2, id2, fgf10, fgfr2, and shh were evaluated after RA treatment to disclose a putative molecular network underlying RA effect. In situ hybridization analysis showed that RA is able to alter cyp26a1, sox9, tgf beta 2, and id2 spatial distribution; to increase rar beta, meis2, and hoxb5 expression levels; and has a very modest effect on sox2, fgf10, fgfr2, and shh expression levels. Overall, these findings support a role for RA in the proximal-distal patterning and branching morphogenesis of the avian lung and reveal intricate molecular interactions that ultimately orchestrate branching morphogenesis.The authors would like to thank Ana Lima for slide sectioning and Rita Lopes for contributing to the initiation of this project. This work has been funded by FEDER funds, through the Competitiveness Factors Operational Programme (COMPETE), and by National funds, through the Foundation for Science and Technology (FCT), under the scope of the Project POCI-01-0145-FEDER-007038; and by the Project NORTE-01-0145- FEDER-000013, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio

Interactions between whole-body heating and citalopram on body temperature, antidepressant-like behaviour, and neurochemistry in adolescent male rats

Evidence suggests that affective disorders are associated with altered thermoregulation, and it has been hypothesized that therapeutic strategies targeting body-to-brain thermosensory systems may be effective for treating depression. Consistent with this hypothesis, a recent randomized, double blind, placebo-controlled clinical trial has suggested that infrared whole-body hyperthermia has therapeutic potential for the treatment of depression. Preclinical models may help uncover the mechanism(s) underlying the antidepressant-like effects of whole-body heating. We have previously shown that exposure to whole-body heating potentiates antidepressant-like behavioural responses following administration of a behaviourally subthreshold dose of the selective serotonin reuptake inhibitor citalopram, but the neurochemical and behavioural interactions between whole body heating and behaviourally effective doses of citalopram are not known. In these experiments, we examined the effects of whole-body heating, either with or without treatment of a suprathreshold dose of citalopram (20 mg/kg, s.c.), on body temperature, antidepressant-like behavioural responses in the forced swim test, and tissue concentrations of serotonin and its metabolite, 5-hydoxyindoleacetic acid (5-HIAA), in the prefrontal cortex of adolescent male Wistar rats. Although whole-body heating did not potentiate the behavioural effects of suprathreshold citalopram, citalopram was observed to increase body temperature and potentiate the effects of whole-body heating on body temperature. Whole-body heating, by itself, decreased serotonin concentrations in the infralimbic cortex to a level similar to that observed following treatment with citalopram, suggesting that these treatments have convergent effects on a mesolimbocortical system innervating the medial prefrontal cortex, an effect that was correlated with effects of treatment on body temperature