Strength and microstructure of mortar with sand substitutes

U radu se razmatra čvrstoća i mikrostruktura morta u kojem se kao zamjena za riječni pijesak (RS) koriste drobljeni pijesak (MS) i granitni prah (GP) u raznim udjelima. Za postizanje maksimalne tlačne čvrstoće i vlačne čvrstoće pri cijepanju, optimalni težinski udio GP u RS iznosi 15 %. Svojstva čvrstoće morta koji sadrži MS bolja su od odgovarajućih svojstava mortova RS i GP, bez obzira na vrijeme njege. Za mortove MS i GP provedena je toplinska analiza, mikrostrukturna analiza i mineraloška analiza, a pritom su korišteni postupci TGA, SEM, XRD i FT-IR.The strength and microstructure of mortars incorporating manufactured sand (MS) and various levels of granite powder (GP) as substitutes for river sand (RS) are considered in the paper. The optimum RS substitution by GP is 15 % by mass for the maximum compressive and splitting tensile strength. Strength properties of mortars containing MS are better when compared to RS and GP mortars, irrespective of the curing period. The thermal analysis, microstructural analysis, and mineralogical analysis are conducted on MS and GP mortars using TGA, SEM, XRD and FT-IR techniques

Rebar properties in sand-substitute mortars after exposure to high temperatures

U ovom se radu istražuje utjecaj zagrijavanja, metoda hlađenja i debljine zaštitnog sloja na ponašanje (čvrstoću i duktilnost) rebraste armature promjera 12 mm ugrađene u mort u kojem je riječni pijesak zamijenjen granitnim prahom i proizvedenim pijeskom, pri čemu debljina zaštitnog sloja iznosi 30 i 50 mm. Na temperaturama iznad 500 °C, toplinsko naprezanje uzrokovalo je nasumično ljuskanje zaštitnog sloja, a vlačna ispitivanja upozorila su na smanjenje čvrstoće i povećanje duktilnosti armature pri hlađenju na zraku, dok je suprotna pojava uočena pri gašenju vodom.This study investigates the effects of fire, cooling methods, and cover thickness, on the behaviour (strength and ductility) of 12-mm diameter rebars embedded in mortars with river sand (RS) substitutes such as granite powder and manufactured sand, with 30 and 50 mm cover thickness. Beyond 500°C, thermal stress induced random spalling of mortar cover, and tension test results showed strength decrement and ductility increment of rebars for air cooling, while the vice versa was observed for water quenching

Sodium-coupled Monocarboxylate Transporters in Normal Tissues and in Cancer

SLC5A8 and SLC5A12 are sodium-coupled monocarboxylate transporters (SMCTs), the former being a high-affinity type and the latter a low-affinity type. Both transport a variety of monocarboxylates in a Na+-coupled manner. They are expressed in the gastrointestinal tract, kidney, thyroid, brain, and retina. SLC5A8 is localized to the apical membrane of epithelial cells lining the intestinal tract and proximal tubule. In the brain and retina, its expression is restricted to neurons and the retinal pigment epithelium. The physiologic functions of SLC5A8 include absorption of short-chain fatty acids in the colon and small intestine, reabsorption of lactate and pyruvate in the kidney, and cellular uptake of lactate and ketone bodies in neurons. It also transports the B-complex vitamin nicotinate. SLC5A12 is also localized to the apical membrane of epithelial cells lining the intestinal tract and proximal tubule. In the brain and retina, its expression is restricted to astrocytes and Müller cells. SLC5A8 also functions as a tumor suppressor; its expression is silenced in tumors of colon, thyroid, stomach, kidney, and brain. The tumor-suppressive function is related to its ability to mediate concentrative uptake of butyrate, propionate, and pyruvate, all of which are inhibitors of histone deacetylases. SLC5A8 can also transport a variety of pharmacologically relevant monocarboxylates, including salicylates, benzoate, and γ-hydroxybutyrate. Non-steroidal anti-inflammatory drugs such as ibuprofen, ketoprofen, and fenoprofen, also interact with SLC5A8. These drugs are not transportable substrates for SLC5A8, but instead function as blockers of the transporter. Relatively less is known on the role of SLC5A12 in drug transport

Prediction of overall survival for patients with metastatic castration-resistant prostate cancer : development of a prognostic model through a crowdsourced challenge with open clinical trial data

Background Improvements to prognostic models in metastatic castration-resistant prostate cancer have the potential to augment clinical trial design and guide treatment strategies. In partnership with Project Data Sphere, a not-for-profit initiative allowing data from cancer clinical trials to be shared broadly with researchers, we designed an open-data, crowdsourced, DREAM (Dialogue for Reverse Engineering Assessments and Methods) challenge to not only identify a better prognostic model for prediction of survival in patients with metastatic castration-resistant prostate cancer but also engage a community of international data scientists to study this disease. Methods Data from the comparator arms of four phase 3 clinical trials in first-line metastatic castration-resistant prostate cancer were obtained from Project Data Sphere, comprising 476 patients treated with docetaxel and prednisone from the ASCENT2 trial, 526 patients treated with docetaxel, prednisone, and placebo in the MAINSAIL trial, 598 patients treated with docetaxel, prednisone or prednisolone, and placebo in the VENICE trial, and 470 patients treated with docetaxel and placebo in the ENTHUSE 33 trial. Datasets consisting of more than 150 clinical variables were curated centrally, including demographics, laboratory values, medical history, lesion sites, and previous treatments. Data from ASCENT2, MAINSAIL, and VENICE were released publicly to be used as training data to predict the outcome of interest-namely, overall survival. Clinical data were also released for ENTHUSE 33, but data for outcome variables (overall survival and event status) were hidden from the challenge participants so that ENTHUSE 33 could be used for independent validation. Methods were evaluated using the integrated time-dependent area under the curve (iAUC). The reference model, based on eight clinical variables and a penalised Cox proportional-hazards model, was used to compare method performance. Further validation was done using data from a fifth trial-ENTHUSE M1-in which 266 patients with metastatic castration-resistant prostate cancer were treated with placebo alone. Findings 50 independent methods were developed to predict overall survival and were evaluated through the DREAM challenge. The top performer was based on an ensemble of penalised Cox regression models (ePCR), which uniquely identified predictive interaction effects with immune biomarkers and markers of hepatic and renal function. Overall, ePCR outperformed all other methods (iAUC 0.791; Bayes factor >5) and surpassed the reference model (iAUC 0.743; Bayes factor >20). Both the ePCR model and reference models stratified patients in the ENTHUSE 33 trial into high-risk and low-risk groups with significantly different overall survival (ePCR: hazard ratio 3.32, 95% CI 2.39-4.62, p Interpretation Novel prognostic factors were delineated, and the assessment of 50 methods developed by independent international teams establishes a benchmark for development of methods in the future. The results of this effort show that data-sharing, when combined with a crowdsourced challenge, is a robust and powerful framework to develop new prognostic models in advanced prostate cancer.Peer reviewe

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Functional features and genomic organization of mouse NaCT, a sodium-coupled transporter for tricarboxylic acid cycle intermediates.

In the present study, we report on the molecular cloning and functional characterization of mouse NaCT (Na+-coupled citrate transporter), the mouse orthologue of Drosophila Indy. Mouse NaCT consists of 572 amino acids and is highly similar to rat and human NaCTs in primary sequence. The mouse nact gene coding for the transporter is approx. 23 kb long and consists of 12 exons. When expressed in mammalian cells, the cloned transporter mediates the Na+-coupled transport of citrate and succinate. Competition experiments reveal that mouse NaCT also recognizes other tricarboxylic acid cycle intermediates such as malate, fumarate and 2-oxo-glutarate as excellent substrates. The Michaelis-Menten constant for the transport process is 38+/-5 mM for citrate and 37+/-6 mM for succinate at pH 7.5. The transport process is electrogenic and exhibits an obligatory requirement for Na+. Na+-activation kinetics indicates that multiple Na+ ions are involved in the activation process. Extracellular pH has a differential effect on the transport function of mouse NaCT depending on whether the transported substrate is citrate or succinate. The Michaelis-Menten constants for these substrates are also influenced markedly by pH. When examined in the Xenopus laevis oocyte expression system with the two-microelectrode voltage-clamp technique, the transport process mediated by mouse NaCT is electrogenic. The charge-to-substrate ratio is 1 for citrate and 2 for succinate. The most probable transport mechanism predicted by these studies involves the transport of citrate as a tervalent anion and succinate as a bivalent anion with a fixed Na+/substrate stoichiometry of 4:1. The present study provides the first unequivocal evidence for the electrogenic nature of mammalian NaCT

A Comparative Study of Fine‑Needle Aspiration and Nonaspiration Cytology Diagnosis in Thyroid Lesions

Background: Aspiration cytology is one of the first-line diagnostic tests in thyroid malignancies. Fine-needle aspiration cytology (FNAC) in thyroid lesions causes hemorrhagic smear and cell trauma, often leading to the repetition of smear and delay in diagnosis. This study was conducted to identify the diagnostically superior technique with regard to thyroid swelling and to assess the quality of smears obtained from FNAC and fine-needle nonaspiration cytology (FNNAC). Methodology: This was a prospective diagnostic study carried out for 2 years in a tertiary care center from South India. All patients with complaints of thyroid swellings, after examination, underwent FNNAC, followed by FNAC of the lesion. They underwent thyroidectomy when indicated. The final postoperative biopsy reports were compared with the preoperative reports of these two techniques (FNNAC and FNAC). The quality of smears was compared using Mair's score. Results: The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in diagnosing malignancy were 93.4%, 100%, 100%, 98.78%, and 98.96% for FNNAC and 94.12%, 100%, 100%, 98.82%, and 99% for FNAC, respectively, which were comparable. Regarding the quality of smears, FNNAC had more smears with less blood in the background. FNAC had more smears with adequate cellularity. The difference in overall Mair's score between the two techniques was not significant (P = 0.28). Conclusion: No difference was found in the accuracy of FNAC and FNNAC in diagnosing thyroid lesions. Furthermore, the smear quality of both techniques was comparable. Hence, either can be used based on the operator's preference and experience

Redox-active pigeon excreta mediated metal oxides nanosheets for enhancing co-catalyst for photovoltaic performance in dye-sensitized solar cells

Pigeon excreta (PE) contains a significant amount of organic components, which are harmful to the environment and humans. Hence, the proper disposal of PE deals with practical problems. Furthermore, using PE for other energy sources is an efficient innovation. In this study, an innovative technique was implemented for producing agglomeration free and distinct metal oxides using PE as a surfactant and capping agent. The different characterizations and their analysis explain the mechanism involved in forming distinct metal oxide nanosheets utilizing PE. The obtained samples were confirmed by the characteristic peaks of PE mediated metal oxides such as (NiO, Co3O4 and CuO) observed in X-ray diffraction (43.47°, 36.61° and 35.71°), and the UV-DRS band-gap narrowing (2.4, 2.13 and 2.02 eV). In the FTIR spectrum, it is clearly evident that there is a high amine group in the PE which plays a key role in reducing the agglomeration in the metal oxides. The morphology of PE mediated NiO, Co3O4 and CuO revealed nanoflakes and nanosheets like structures identified from FE-SEM analysis. The photovoltaic performance of the PE mediated metal oxides showed improved photocurrent conversion efficiencies of 1.2–1.6 times more than pure metal oxides. Among all, the CuO-PE had the most significant photovoltaic performance, with a photoconversion efficiency of 3.22 %. The reduction of I3− to 3I− along the counter electrode/electrolyte interaction is facilitated by the PE mediated transition metal oxides, as shown by the photocurrent response, Tafel plot and electrical impedance spectroscopy results, which were discussed in detail