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An endeavour was put forward to friction stir weld flat plates of AZ80A Mg alloy by employing the central composite based design technique of response surface methodology, taking into consideration the parameters namely tool rotational speed, traverse speed, tool’s tilt angle, and pin geometry of the employed tool. Numerical model was formulated to correlate the relationship amidst the employed parameters of FSW process and the responses, namely tensile strength and elongation percentage of the AZ80A Mg alloy joints. The formulated model was also optimized to attain AZ80A Mg alloy joints possessing highest value of tensile strength. Competency of the formulated numerical model was validated employing the analysis of variance and the observations of the affirmation experiments plotted in the form of scatter diagrams revealed an appreciable agreement with the values of the anticipated models. Response and contour plots generated from the established numerical model was employed to understand the interactive impacts of the parameters of FSW process on the variables of the response. AZ80A mg alloy joints fabricated during the employment of tool possessing straight cylindrical geometry at atilt angle of 0.630, rotational speed of 962.077 rpm, tool traverse speed of 2.105 mm sec ^−1 possessed the highest tensile strength of 195.299 MPa and was proven to be free from flaws.

This experimental investigation aims to formulate quadratic regression based empirical model taking into account the parameters of friction stir welding (FSW) process for predicting the optimized process parameters to maximize the response (i.e., ultimate tensile strength) of the distinctive alloys of Mg joints. Parameters of FSW process taken into consideration includes tool’s traverse speed, axial force and rotational speed of tool and response being the fabricated joint’s tensile strength. A central composite rotatable category 3–factor, 5 level design based matrix was formulated and response surface methodology was used to obtain regression based models, to generate contour plots and to visualize the interactive impacts of parameters on the joint’s tensile strength. Formulated quadratic regression based model was validated employing analysis of variance. Comparison amidst the realistic and anticipated values of the response announced the superior fitting accuracy of the formulated quadratic model. For a constant tool’s rotational speed (of 1000 rpm to 1250 rpm), the tensile strength was observed to be highly sensitive to the axial force values than the tool traverse speed values. Mean tensile strength of the friction stir welded AZ31B, AZ80A, AZ91C, AM50A and ZK51A-T5 Mg joints during the employment of optimized process parameters were found to be 217.5 MPa, 251.4 MPa, 231.9 MPa, 192.1 MPa and 173.2 MPa respectively, thereby exhibiting perfect agreement with the anticipated values.

High-performance steel has emerged as an advanced structural material in the construction practice of industrial buildings, due to its excellent properties. However, fire poses a significant threat to cold-formed steel structures, as they are prone to deform and buckle under the exposure, potentially leading to building collapse. This study aimed to evaluate the post-fire web-crippling behaviour of high performance CFS sections for End Two Flange (ETF) and Interior Two Flange (ITF) load cases. Two types of specimens were used: CFS webs without holes and CFS webs with circular holes. All test specimens were heated according to the ISO 834 standard fire curve and were subsequently cooled by air or water. A total of 52 specimens (ambient and post-fire) were tested under ETF and ITF load conditions. The load-deflection behaviour and failure modes were evaluated through experimental and numerical analysis. Finite element modelling was used to compare the load-deflection behaviour and failure modes of CFS members with experimental results. The experimental results indicate that the web load-carrying capacity of the high-performance steel member decreases drastically as the heating duration increases. Furthermore, the ITF load case specimens exhibited a lower strength loss than the ETF load case specimens at elevated temperatures. There was an excellent agreement between the experimental and FEM results in terms of the load-carrying capacity and failure modes of high performance CFS.

Tuberculosis (TB) is a chronic condition that weakens the immune system, causes structural changes in the lungs, and can lead to infections by other bacterial pathogens. Very few studies have been done to understand the magnitude of co-infection with other bacterial pathogens, so this study was conducted to understand the co-infection pattern and burden. A total of 174 microbiologically confirmed pulmonary TB patients' samples, identified by cartridge-based nucleic acid amplification test, were further tested for other bacterial pathogens by culture over a period of five months from May 2023 to September 2023. The isolates' identification and drug susceptibility were performed using the VITEK 2 system (bioMérieux, Marcy-l'Étoile, France). Of the 174 pulmonary samples tested, 19 samples grew a significant amount of other bacterial pathogens, making the prevalence 10.91% (19/174). Among the pulmonary samples tested, 54.59% were sputum, 38.5% were bronchoalveolar lavage, and 6.89% were endotracheal aspirate. Additionally, 70.11% of the patients tested were in the age group of 19-60 years. Of the patients who had co-infection, 94.73% (18/19) were male. The most common bacterial infection was caused by Pseudomonas aeruginosa , which was identified in 36.84% of the co-infection cases (7/19). This was followed by Acinetobacter baumannii in 31.57% (6/19), Klebsiella pneumoniae in 26.31% (5/19), and Stenotrophomonas maltophilia in 5.28% (1/19). Acinetobacter baumannii and Klebsiella pneumoniae showed high drug resistance, ranging from 60% to 100% against various groups of drugs tested. None of the patient samples with co-infection showed rifampicin resistance. Among all the samples with co-infection, the majority (42.10%, or 8/19) had a high load of Mycobacterium tuberculosis complex detected by CBNAAT Ultra (Cepheid, Sunnyvale, California). Pseudomonas aeruginosa , Acinetobacter baumannii , and Klebsiella pneumoniae are unusual pathogens causing infection in community patients and are known to cause illness in hospitalized patients. These organisms' resistance was also similar to the resistance shown by hospital-acquired infections. This indicates that bacterial co-infection in pulmonary TB patients will be similar to the pattern of hospital-acquired infections. The high prevalence of bacterial co-infections (10.91%) in patients with pulmonary TB poses a significant challenge as these bacterial pathogens are not susceptible to anti-tubercular drugs. Therefore, comprehensive screening for other bacterial infections in all pulmonary TB patients is crucial for effective treatment and outcomes., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Institutional Ethics Committee of ESIC MC&H, Faridabad issued approval 134 X/11/13/2024- IEC/DHR/04. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Bir et al.)

We report a rare case of splenic tuberculosis (TB) in a male patient with a competent immune system who had no previous record of pulmonary TB. A 56-year-old male patient came to our outpatient department complaining of upper abdominal pain with a few episodes of vomiting for three days. He had alcoholism, smoked for 15 years, and had no past history of diabetes mellitus, hypertension, TB, or HIV. An abdominal ultrasound and CT scan at admission showed pancreatitis with a splenic abscess. After five days of admission, the patient's vitals deteriorated, and he had severe abdominal pain. CT scan suggested a splenic abscess rupture with hemoperitoneum. An emergency exploratory laparotomy was performed, and a splenectomy was done due to the splenic abscess rupture. A cartridge-based nucleic acid amplification test from splenic intracapsular fluid detected a trace Mycobacterium tuberculosis complex. The patient was discharged after starting first-line antitubercular treatment for six months. After three months of follow-up, the patient was doing well with no complaints., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Ranjan et al.)

Background: This study aims to compare the performance of line probe assay (LPA) on smear-negative samples with that of smear-positive samples for diagnosing pulmonary tuberculosis (PTB) and first-line drug sensitivity testing (FL DST)., Methods: A total of 196 sputum samples including both smear-positive (112) and negative (84) samples of patients suspected of PTB were subjected to LPA for TB detection and FL DST. TB culture followed by MPT 64 Ag was done and conventional FL DST was performed on all culture-positive isolates. Results of LPA on smear-negative were compared with smear-positive samples., Results: The LPA confirmed the diagnosis of PTB in 104/112 smear-positive cases but in only 36/84 smear-negative cases. The assay had 47.36%, 72.72%, and 88.88% sensitivity and 86.96%, 95.23%, and 95.65% specificity in smear-negative cases compared to 89.09%, 95.83%, and 98.07% sensitivity and 100%, 98.36%, and 98.24% specificity in smear-positive cases for detecting Mycobacterium tuberculosis (MTB), rifampicin (RMP) resistance, and isoniazid (INH) resistance, respectively., Conclusion: LPA performance was better on smear-positive than smear-negative sputum samples. Further larger studies are needed to justify the use of LPA on smear-negative pulmonary samples for diagnosis., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Nandwani et al.)

A highly selective turn-on sensor for paramagnetic Fe 3+ ions based on (E)-N'-((2-aminophenyl)(phenyl)methylene)thiophene-2-carbohydrazide is successfully synthesized. The sensor BPTH is significantly selective and sensitive towards Fe 3+ ions over other interfering metal ions especially Cu 2+ and Co 2+ ions with a lowest limit of recognition 1.48 × 10 -7  M. The turn-on sensing mechanism involves enhanced charge transfer. Fe 3+ ion forms strong binding with the ligand with a K a value about 8.23 × 10 4  M -1 and a 1:1 stoichiometric ratio is confirmed by Job's plot experiment. With Fe 3+ ion, the yellow ligand BPTH change to a green fluorescent and reversible with 1 equivalent of EDTA. Practical application of sensor is demonstrated in real sample analysis., (© 2023. The Author(s), under exclusive licence to European Photochemistry Association, European Society for Photobiology.)

A novel quinoxaline-hydrazinobenzothiazole based sensor was synthesized and characterized using NMR, FTIR, and Mass spectroscopy techniques. The sensor achieves the distinct "single-point" colorimetric and fluorescent detection of Cu 2+ , Co 2+ , Ni 2+ and Hg 2+ ions with distinguishable color changes from yellow to red, pale red, pale brown and orange, respectively. The UV-visible and fluorescence emission spectral investigation revealed the excellent single-point sensing ability of the probe towards four different heavy metal ions with a ratiometric response. Nanomolar levels of detection of about 1.16 × 10 -7 M, 9.92 × 10 -8 M, 8.21 × 10 -8 M, and 1.14 × 10 -7 M for Cu 2+ , Co 2+ , Ni 2+ and Hg 2+ ions, respectively, were achieved using our sensor, which are below the US-EPA permissible limits. Additionally, the sensor was utilized for naked eye detection under normal daylight. Quantitative determination of the metal ions in real water samples was also demonstrated.

The increase in the population creates an increased demand for construction activities with eco-friendly, sustainable, and high-performance materials. Insulated concrete form (ICF) is an emerging technology that satisfies the sustainability demands of the construction sector. ICF is a composite material (a combination of expanded polystyrene (EPS) and geopolymer concrete (GPC)) that enhances the performance of concrete (such as thermal insulation and mechanical properties). To investigate the axial strength performance, five different types of prototypes were created and tested. Type I (without reinforcement): (a) hollow EPS without concrete, (b) alternative cells of EPS filled with concrete, (c) and all the cells of EPS filled with concrete; and Type II (with reinforcement): (d) alternative cells of EPS filled with concrete; (e) and all the cells of EPS filled with concrete. Amongst all the five prototypes, two grades of GPC were employed. M15 and M20 grades are used to examine the effectiveness in terms of cost. For comparing the test results, a reference masonry unit was constructed with conventional clay bricks. The main aim of the investigation is to examine the physical and mechanical performance of sandwich-type ICFs. The presence of polystyrene in ICF changes the failure pattern from brittle to ductile. The result from the study reveals that the Type II prototype, i.e., the specimen with all the cells of EPS filled with concrete and reinforcement, possesses a maximum load-carrying capacity greater than the reference masonry unit. Therefore, the proposed ICF is recommended to replace the conventional load-bearing system and non-load-bearing walls.

Background: Rapidly growing mycobacteria (RGM) comprise nearly half of the validated species of nontuberculous mycobacteria (NTM) and have been reported to have a higher incidence in Asia as compared to Europe and America. There is limited information on RGM infections from South Asia. Hence, the present study aimed to ascertain the incidence of pulmonary infections due to RGM in Delhi and to review the status of available information on the prevalence of RGM in South Asia, a region endemic for tuberculosis., Methods: We analyzed 933 mycobacterial isolates obtained from pulmonary samples in Delhi and performed species identification by polymerase chain reaction (PCR)-restriction analysis (restriction fragment length polymorphism) and line probe assay. Drug susceptibility testing (DST) was performed by broth microdilution method. We also reviewed reports available on pulmonary infections in South Asia, attributed to RGM., Results: Of the 933 mycobacterial isolates studied, NTM were identified in 152 (16.3%). Of these, 65/152 (42.8%) were RGM comprising Mycobacterium fortuitum (34/65; 52.3%), Mycobacterium abscessus (25/65; 38.5%), Mycobacterium chelonae (3/65; 4.61%), Mycobacterium mucogenicum (2/65; 3.1%), and Mycobacterium smegmatis (1/65; 1.5%). On applying the American Thoracic Society/Infectious Diseases Society of America guidelines, 11/25 (44%) M. abscessus, 3/3 (100%) M. chelonae, and both isolates of M. mucogenicum were found to be clinically relevant. DST revealed that maximum susceptibility of the RGM was seen to linezolid, clarithromycin, and amikacin., Conclusions: Of the RGM isolated in the present study, 16/65 (24.6%) were found to be clinically relevant. Hence, it is important to recognize these organisms as potential pathogens to identify patients with RGM disease to initiate appropriate therapy., Competing Interests: None

Background: The mortality associated with lower respiratory tract infection is high. Indiscriminate use of antimicrobials leads to alteration of respiratory tract flora and development of multi-drug resistance. Rapid diagnostic tests to confirm infection can guide the clinicians about antimicrobial treatment. So the present study was planned to evaluate the role of direct gram stain examination as a rapid and simple test to help clinicians for appropriate patient management., Methods: The present study was conducted on 1000 respiratory specimens which were processed using conventional microbiological techniques. Gram stain smear and culture results were compared statistically to assess the sensitivity, specificity, positive and negative predictive value. The agreement between gram stain smear examination and culture was calculated using kappa statistics., Results: Potential pathogens were obtained from 28 of 209 deeply coughed out sputum samples (13.3%) and from 19 of 315 saliva mixed sputum samples (6%). Out of 473 tracheal aspirates, 115 (24.3%) had potential pathogens. The sensitivity for predicting infection was higher for good quality sputum samples (54%) as compared to poor quality sputum samples (37%). The gram stain and culture of tracheal samples had a good agreement for predicting infection whereas there was only moderate agreement for sputum sample., Conclusion: Gram stain smear examination from respiratory samples can be used to guide empiric antibiotic therapy pending final culture sensitivity results if the attending physicians ensure appropriate sample collection and transport. In absence of these supportive measures smear examination should not be relied upon for empiric treatment., (Copyright © 2019. Published by Elsevier B.V.)

Nocardia, a branching, filamentous bacteria, is widely distributed in the environment and can cause human infection in immune-compromised hosts. Inhalation of Nocardia leads to pulmonary disease. Microbiology laboratory processed the clinical samples from patients with respiratory infections. Smears were prepared from the samples and were stained and cultured. Five cases were positive for Nocardia. They were treated with the trimethoprim-sulfamethoxazole combination. The disease was cured in three patients, and two died due to other comorbid conditions leading to complications. Nocardiosis is encountered in parts of the world even where it is not endemic due to increased world travel. So physicians and laboratory staff should be aware of this and try to diagnose it. Early detection can lead to the prompt initiation of treatment and reduced mortality in these patients. Patients with disseminated or severe nocardiosis should be treated with combination therapy with two or more active agents.

Background: With the evolution of education, there has been a shift from the use of traditional teaching methods, such as didactic or rote teaching, towards non-traditional teaching methods, such as viewing of role plays, simulation, live interviews and the use of virtual environments. Mental state examination is an essential competency for all student healthcare professionals. If mental state examination is not taught in the most effective manner so learners can comprehend its concepts and interpret the findings correctly, it could lead to serious repercussions and subsequently impact on clinical care provided for patients with mental health conditions, such as incorrect assessment of suicidal ideation. However, the methods for teaching mental state examination vary widely between countries, academic institutions and clinical settings., Objectives: This systematic review aimed to identify and synthesize the best available evidence of effective teaching methods used to prepare student health care professionals for the delivery of mental state examination., Inclusion Criteria: This review considered evidence from primary quantitative studies which address the effectiveness of a chosen method used for the teaching of mental state examination published in English, including studies that measure learner outcomes, i.e. improved knowledge and skills, self-confidence and learners' satisfaction., Search Strategy: A three-step search strategy was undertaken in this review to search for articles published in English from the inception of the database to December 2014. An initial search of MEDLINE and CINAHL was undertaken to identify keywords. Secondly, the keywords identified were used to search electronic databases, namely, CINAHL, Medline, Cochrane Central Register of Controlled Trials, Ovid, PsycINFO and, ProQuest Dissertations & Theses. Thirdly, reference lists of the articles identified in the second stage were searched for other relevant studies., Methodological Quality: Studies selected were assessed by two independent reviewers for methodological validity prior to inclusion in the review using the standardized critical appraisal instruments from the Joanna Briggs Institute's Meta-Analysis of Statistics Assessment and Review Instrument embedded within the System for the Unified Management, Assessment and Review of Information. Any disagreements that arose between the reviewers were resolved through discussion between the reviewers., Data Extraction: Data was extracted using data extraction tools developed by the Joanna Briggs Institute Quantitative data was extracted from papers using standardized data extraction tools from the Joanna Briggs Institute's Meta-Analysis of Statistics Assessment and Review Instrument., Data Synthesis: The included studies were found to be heterogeneous in terms of participants and teaching methods. Moreover, a wide variety of instruments were used to determine impact and outcomes of the teaching methods. Hence, findings of the included articles were presented in a narrative summary., Results: A total of 12 articles were included in this review with consensus from all reviewers. The evidence retrieved in this study suggests that non-traditional teaching methods, such as videotapes, virtual simulation, standardized patients and reflection, improve learners' understanding and skills of mental state examination as opposed to traditional teaching methods like lectures and provision of reading materials. However, studies that specifically compared the effectiveness of one method over another were limited to comparison between lectures with videotaped interviews and virtual simulations. It was shown that both videotaped interviews and virtual simulations were superior to lectures. In videotaped teaching, interactions between patients and learners performing mental state examination were shown for the learner’s discussion while virtual simulations mimicked patient symptoms in computer applications. Virtual simulation was notably a unique learning opportunity for the learners as it allowed learning to take place without the use of diminishing real life resources. However, in view of the high cost and learners’ difficulty in negotiating the virtual environment, videotaped teaching remained as the more commonly used method of teaching mental state examination., Conclusions: This systematic review study identified teaching strategies utilized in the teaching of mental state examination and their effectiveness. Videotapes was the most widely used and effective approach, that is, until the issue of high cost and ease of maneuver in virtual simulation could be overcome. There were also potential benefits of other teaching, such as reflection and use of standardized patients, and educators could consider these in the teaching of mental state examination. Future research could focus more on the comparison of various teaching methods to offer more evidence on the use of one teaching method over another., (The Joanna Briggs Institute.)