Effect of plasma sprayed flyash based composite coatings on corrosion resistance.

With the aim of exploring the possibility of achieving a low-cost thermal spray coating to prevent wear, erosion and corrosion. In the current study, flyash-Al2O3 and flyash-SiC composite coatings were effectively created using the air plasma spray process on substrates of Al6061 alloy. NiCr material is used as the bond coat to improve the bond strength between the coat and the substrate. Taguchi's DoE method is applied to for spray process parameters optimization. In addition, the developed coating is subjected to microstructure analysis and long-term immersion corrosion testing (1 year) in an aqueous environment to assess corrosion properties. The results revealed that the over a certain test period, the developed flyash-SiC coating has greater corrosion resistance than the uncoated and flyash-Al2O3 coated Al6061. It is noticed that the corrosion resistance of the flyash-Al2O3 coating shifts to a negative value with respect to the uncoated substrate. The uncoated sample is extensively pitted and locally corroded, as shown by the SEM image of the corroded surface. Flyash-corroded Al2O3's surface exhibits extensive degradation in the form of peeling, breaking, and cracking of the splats. With flyash-SiC composite coating a very minor corrosion splat deterioration is seen.

Urodynamic profile of lower urinary tract symptoms in young men: A testimony of the truth?

Aim: To evaluate the impact of urodynamic study (UDS) in the management of young men presenting with lower urinary tract symptoms (LUTSs). Materials and Methods: This is a retrospective, observational study of urodynamic findings of 128 patients presented with LUTS at the Department of Urology, Institute of Nephrourology, Bangalore, over a period of 5 years (August 2014 to July 2019). Pre- and post-UDS diagnoses as well as treatment modalities were compared to evaluate the usefulness of UDS. Results: A total of 110 patients (86%) had abnormal UDS findings. Before UDS, 55 (43%) patients were clinically diagnosed for overactive bladder; after UDS, bladder outlet obstruction (BOO) was seen in 32 (25%) patients and detrusor overactivity in 18 (14.1%). Clinically, BOO was diagnosed in 36 (28.1%) patients; however, urodynamic findings of BOO were seen only in 23 (18%) patients. Pre-UDS, bladder underactivity was suspected in 23 (18%); however, underactive detrusor was noted in 20 (15.6%) patients, and 3 (2.4%) patients were normal on UDS. Post-UDS, antibiotics were not prescribed to anyone. 18 (14%) patients underwent surgery after UDS confirmation of BOO. 67 patients (52.3%) had their clinical diagnosis changed following UDS. Concomitant changes in the management were required for 59 patients (46%). Conclusion: Etiologies of LUTSs in young men are more varied. Clinical diagnosis and treatment are often empirical and inaccurate. UDS is useful to achieve accurate diagnosis and to guide appropriate treatment. Video urodyanamics should be used to evaluate LUTS in young men.

Influence of Solid Lubricant Addition on Friction and Wear Response of 3D Printed Polymer Composites.

In this study, acrylonitrile butadiene styrene (ABS) and graphite powder-a solid lubricant-were filled and characterized for friction and wear responses. The fused deposition modeling (FDM) technique was utilized to synthesize ABS-graphite composites. A twin-screw extrusion approach was employed to create the composite filament of graphite-ABS that is suitable for the FDM process. Three graphite particle ratios ranging from 0% to 5% were explored in the ABS matrix. The wear and friction properties of ABS composites were examined using a pin on disc tribometer at varied sliding velocities and weights. As a result of the graphite addition in the ABS matrix, weight losses for FDM components as well as a decreased coefficient of friction were demonstrated. Furthermore, as the graphite weight percentage in the ABS matrix grows the value of friction and wear loss decreases. The wear mechanisms in graphite filled ABS composites and ABS were extensively examined using scanning electron microscopy and confocal microscopy.

Mechanical Properties of PC-ABS-Based Graphene-Reinforced Polymer Nanocomposites Fabricated by FDM Process.

This experimental study investigates the mechanical properties of polymer matrix composites containing nanofiller developed by fused deposition modelling (FDM). A novel polymer nanocomposite was developed by amalgamating polycarbonate-acrylonitrile butadiene styrene (PC-ABS) by blending with graphene nanoparticles in the following proportions: 0.2, 0.4, 0.6, and 0.8 wt %. The composite filaments were developed using a twin-screw extrusion method. The mechanical properties such as tensile strength, low-velocity impact strength, and surface roughness of pure PC-ABS and PC-ABS + graphene were compared. It was observed that with the addition of graphene, tensile strength and impact strength improved, and a reduction in surface roughness was observed along the build direction. These properties were analyzed to understand the dispersion of graphene in the PC-ABS matrix and its effects on the parameters of the study. With the 0.8 wt % addition of graphene to PC-ABS, the tensile strength increased by 57%, and the impact resistance increased by 87%. A reduction in surface roughness was noted for every incremental addition of graphene to PC-ABS. The highest decrement was seen for the 0.8 wt % addition of graphene reinforcement that amounted to 40% compared to PC-ABS.

Analysis of the Effect of Parameters on Fracture Toughness of Hemp Fiber Reinforced Hybrid Composites Using the ANOVA Method.

In today's world, global warming has become a concern. To overcome this, we need to reduce the carbon footprints caused by the production of materials. Much of the time, this is equivalent to the same amount of CO2 emissions per tonne of production. This is a serious concern and needs to be overcome by identifying alternative materials to have as minimal a carbon footprint as possible. In this context, hemp fiber is by far the best natural fiber when compared to its peers. As per the survey conducted by the Nova institute, hemp has CO2 emissions of only 360 Kg/tonne, whereas jute has CO2 emissions of 550 Kg/tonne, kenaf 420 Kg/tonne, and flax 350 Kg/tonne. This paper presents an experimental study of the fracture toughness of hemp-reinforced hybrid composites (HRHC). The effect of the parameters on the fracture toughness behavior of HRHC is studied using the Taguchi technique. It uses different filler combinations with hemp fiber and epoxy. Hemp fiber is used as the reinforcement, epoxy resin is used as a matrix, and banana fiber, coconut shell powder, and sawdust are used as fillers. The experimental plan is prepared using an orthogonal array and analyzed using Minitab software. The obtained results were analyzed using ANOVA and main effects plots. It was observed that the fracture toughness increases with a decrease in thickness. The fracture toughness is affected by the fiber content in the range of 25%-35% and is also affected by the filler materials.

A comparative study of minimally invasive percutaneous nephrolithotomy and retrograde intrarenal surgery for solitary renal stone of 1-2 cm.

BACKGROUND: PCNL is the treatment of choice for renal stones. But wide array of complications due to larger tract size(>20 Fr) has lead to development of improved techniques like miniPCNL(<20 Fr) and RIRS(Retrograde intrarenal surgery). AIM AND OBJECTIVE: To perform a study comparing miniPCNL with RIRS for renal stones 1-2 cm with respect to stone free rate , complications and quality of life. MATERIALS AND METHODS: A prospective, randomised study was carried out our tertiary care centre, recruiting 40 patients in each group from Dec 2016 to Oct 2018. Patients demographic characteristics, operative findings, surgical outcomes and quality of life( SF-36 questionnaire) were recorded with 3 months of follow-up. RESULTS: RIRS has longer operative time (69.75 min > 51.58 min; p=0.003), lesser radiation exposure (p=0.012), shorter hospital stay (p =0.15), lesser blood loss and lesser post operative pain on POD1 and POD2 (p =0.005, p=0.001 respectively). RIRS group patients sufferred more post op complications (p=0.03 )of which urosepsis was most common. Stone free rate is significantly better(p =0.003) in miniPCNL group on POD1 , while SFR's at 1 month (miniPCNL-90% and RIRS -85%) and 3 month (miniPCNL- 92.5% and RIRS -87.5%) was better in miniPCNL group, but statistically insignificant.On subgroup analysis SFR in lower pole calculus was better in miniPCNL group at 1month and 3 month (p=0.008). Second intervention for stone clearance was required in 3 patients of miniPCNL and 5 patients of RIRS, out of which 4 had lower pole stone.No significant differnce was found in quality of life in both groups at 1 month. CONCLUSION: MiniPCNL is a better treatment modality for higher single step stone free rate, shorter operative time and fewer postop complication. RIRS has SFR slightly less than miniPCNL but has less radiation exposure and much less post operative pain. There is no significant difference in quality of life in both groups.

Emergence of additive manufacturing in global scale during the crisis of 2019-nCoV (novel corona virus).

The global pandemic COVID-19 has emerged as a bane for the human race. The emergence of this disease was initially noted in Wuhan, China and slowly spreading to large number of countries. The greater number of positive cases and increasing mortality rate clubbed with no prescribed medication to cure has led to greater impact on global society and has badly hit the manufacturing sector. Additive Manufacturing (AM) is considered to be primary source of manufacturing in meeting the supply chain towards medical devices and protection kits. This paper discusses the response of global AM community in development of essential products in the desired time span for greater cure.

Identification of risk factors associated with Coxiella burnetii infection in cattle and buffaloes in India.

The etiological agent Coxiella burnetii is a highly infectious gram-negative bacterium that can affect multiple species. Many reports confirm its presence in humans, domestic ruminants and rodents in India. This study was aimed to investigate the risk factors associated with C. burnetii infection in bovine populations in Punjab, India. This study was conducted using a stratified two-stage random sampling approach. Twenty-two villages representing all districts of the state were selected. Bovine farmers were interviewed and detailed information about their management and husbandry practices was collected using a structured questionnaire. Blood, milk and genital swab samples were collected from the cattle and buffaloes owned by the farmers. An animal was declared C. burnetii infected by using a combination of tests in parallel, i.e. if it was positive in serological or molecular tests (IgG indirect ELISA or Trans-PCR assay). A herd was considered positive if at least one animal in the herd was declared C. burnetii infected using the above definition. Three binomial logistic regression models were constructed to evaluate the association of (a) geographical location, herd characteristics, and farm management practices with the herd status (herd model), (b) individual animal related factors with the C. burnetii infection status (individual animal model), and (c) production and health related factors with C. burnetii infection status in adult females (adult female model). We collected a total of 610 blood, 610 genital swabs and 361 milk samples from 378 cattle and 232 buffaloes in 179 herds/households. The practice of throwing away aborted materials outside the farm as compared to burial/burning (adjusted odds ratio [OR] 3.0, 95 % confidence interval [CI] 1.14-7.87, p = 0.02) was associated with larger odds of being a C. burnetii infected herd. On the other hand, separation of the animals from the rest of the herd during parturition had a protective effect for being a C. burnetii infected herd (adjusted OR 0.31, 95 % CI 0.18-0.77, p = 0.01). Being cattle as compared to buffalo (adjusted OR 3.37, 95 % CI 1.23-9.20, p = 0.02) and older (adjusted OR 3.37, 95 % CI 1.23-9.20, p = 0.02) were associated with larger odds of C. burnetii infection. The current study highlights that farm practices such as improper aborted material disposal and not separating the animals from the rest of the herd during parturition are important risks for the occurrence of C. burnetii infection in the bovine populations in the state.

Bilateral retrograde pyelography leading to anuria.

Retrograde pyelography (RGP) is done to evaluate the collecting system when intravenous contrast studies are contraindicated due to renal insufficiency or prior adverse reactions. We report a patient who developed acute renal shutdown following bilateral RGP in the same sitting done for evaluation of positive malignant cytology of urine. A 65-year-old man on treatment for left stroke and hypertension, with a baseline serum creatinine of 1.9 mg/dl presented with painless haematuria for 2 months. Plain computed tomogram revealed a small papillary growth on the posterior wall of the urinary bladder. Transurethral resection revealed inflammatory atypia. As the patient continued to have haematuria, he was taken up for bilateral ureteric washings for cytology and bilateral RGP. A 5-Fr universal ureteral catheter was used to cannulate the ureters, urine was aspirated for cytology and 6 ml of 76% meglumine diatrizoate (1:2) was injected, and sufficient opacification with no abnormality or pyelosinus/venous or lymphatic reflux was noted. In the immediate postoperative period, he developed anuria and the serum creatinine rose to 3.6 mg/dl on postoperative day 1 and to 7.5 mg/dl on day 5. He needed three sessions of haemodialysis. Ultrasonography showed no hydroureteronephrosis. Urine output improved and his serum creatinine stabilized at the preoperative level of 1.8 mg/dl. The patient is doing well with stable renal function at 12 months. Although RGP is useful, it needs to be done with caution if a bilateral procedure is contemplated. This entity is seldom reported, and routine double-J stenting following unilateral/bilateral RGP also needs evaluation.

Prevalence of Coxiella burnetii in cattle and buffalo populations in Punjab, India.

Q fever is an important zoonosis of animal and public health significance but there is very limited information about its prevalence in the Punjab state of India. The current study was designed to estimate Q fever prevalence in cattle and buffalo populations of the state. We randomly selected 22 villages, one from each of the 22 districts of Punjab. Households in these villages were randomly selected using village voter lists to ensure representative sample collection. Blood, vaginal swab and milk samples were collected from the animals in these enrolled households. Serum samples were screened using Coxiella burnetii specific IgG ELISA whereas milk and genital swab samples were subjected to a Trans-PCR assay. The agreement (Cohan's Kappa) between shedding of C. burnetii in milk and genital secretions and between ELISA and Trans-PCR was estimated. The selected PCR products were sequenced, and phylogenetic analyses were performed. We collected 610 blood samples, 610 genital swabs and 361 milk samples from 610 bovines (378 cattle and 232 buffaloes) in 179 households. Considering all tests in parallel and after adjusting for clustering, we estimated an overall individual animal prevalence of Q fever of 7.0% (95% CI: 4.7, 9.4). There was a low agreement between shedding of C. burnetii in milk and genital secretion (kappa: 14.3%; 95% CI: 5.6, 22.9) and between ELISA and Trans-PCR (10.3%; 95% CI: 3.2, 17.4%). Phylogenetic analysis confirmed all samples to be of C. burnetii. The results suggest that the disease is present in the state and further epidemiological information should be collected to determine its zoonotic potential and its impact on animal and public health in Punjab, India.

Evaluation of Testicular Workup for Ischemia and Suspected Torsion score in patients presenting with acute scrotum.

BACKGROUND: Testicular torsion is one of the causes of acute scrotum and it requires timely evaluation and surgical treatment. Color Doppler is considered investigation of choice, but it may delay treatment, as, many times, it may not be available for emergency situations. Barbosa et al. created Testicular Workup for Ischemia and Suspected Torsion (TWIST) score based on clinical parameters for clinical diagnosis of testicular torsion. We have evaluated this score in our population. MATERIALS AND METHODS: We retrospectively calculated TWIST score in patients of acute scrotum admitted to tertiary teaching institute. Patients without complete TWIST score were excluded from the study. The scoring system consisted of testicular swelling (2 points), hard testicle (2), absent cremasteric reflex (1), nausea/vomiting (1), and high-riding testis (1). Statistical analysis was done to evaluate the validity of scores. RESULTS: A total of 118 patients were included in the study, out of which 45 (38%) patients had testicular torsion. The mean age of patients was 16.6 years in testicular torsion patients and 15.2 years in other patients. Cutoff for low-risk and high-risk patients was two and five, respectively. Fifty percent, 26.2%, and 23.8% of patients were present in low-, intermediate-, and high-risk groups. Negative predictive value of TWIST score for low-risk patients was 96.61% while positive predictive value for high-risk patients was 92.86%. CONCLUSIONS: TWIST score has high predictive value and can be used for clinical diagnosis of testicular torsion. It can decrease the need of color Doppler in about 50% of cases and can prevent delay in treatment.

Spectral domain OCT documented resolution of recalcitrant macular edema after intravitreal bevacizumab in branch retinal vein occlusion.

PURPOSE: Cystoid macular edema is one of the important causes of visual loss in branch retinal vein occlusion. Proximity of the cyst to the external limiting membrane and disruption of the layer on time domain optical coherence tomography is associated with poor final visual outcomes. The authors describe pre- and post-intravitreal bevacizumab spectral domain optical coherence tomography features in a case of cystoid macular edema associated with branch retinal vein occlusion that was resolved after treatment with intravitreal bevacizumab. METHODS: A 50-year-old woman was diagnosed with cystoid macular edema due to branch retinal vein occlusion and underwent intravitreal injection with bevacizumab after the primary treatment with laser photocoagulation failed. RESULTS: The patient's visual acuity recovered from 20/40 to 20/20. Spectral domain optical coherence tomography documented complete resolution of a large foveal cyst (150 micronm by 280 micronm) and recovery of the discontinuity of the external limiting membrane 1 week after treatment. CONCLUSIONS: Spectral domain optical coherence tomography is a useful tool in identifying the ultrastructural changes associated with cystoid macular edema associated with branch retinal vein occlusion and identifying the possible factors involved in prognosticating visual outcome after effective treatment.