Effect of GTAW on the Mechanical Properties of Mild Steel

GTAW is considered highly popular in manufacturing. The welding factors such as welding voltage, welding current...etc., play a significant role in determining the welding quality. This study discusses the effect of GTAW factors on the mechanical properties of commercial steel welding. Base metal thickness, welding current and welding speed are factors that will be optimized for maximum tensile strength and hardness using Taguchi’s design. The analysis found that base metal thickness had the highest effect on tensile strength and hardness of the welding, followed by welding current. The welding speed had a lower influence. The optimized combination is the base metal thickness of 10 mm, the welding current of 170A and the welding speed of 100 mm/mi

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

Effect of UV irradiation on apatite deposition on anodised TiO2 coating formed under mixed acid solution

Anodic oxidation method is used to produce thick TiO2 coating layer in a mixture of acids electrolyte to modify the TiO2 which is naturally formed on Ti with only few nanometers thick and inert. The TiO2 coating is then underwent in vitro test to evaluate their bioactivity in simulation body fluid (SBF). In the present work, oxide coatings of TiO2 were formed on Ti-Cp foil under potentials of 150V at current density of 100 mA.cm-2 for 10 min. Multiple characterization techniques were used. X-ray diffraction (XRD) is used to obtain mineralogical phase. Scanning electron microscope (SEM) is used to obtain surface morphology. Chemical absorption of the apatite precipitation was tested by using Fourier transform infrared spectroscopy (FT-IR). Surface morphology from the results shows an increased porosity with smaller pore size for TiO2 formed in mixed acids with higher molar concentration. According to in vitro results it was concluded that apatite precipitation was higher on TiO2 coatings with increased Ti-Ofunctional groups formed using UV