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Simple Summary: The relatively high prevalence of microbial infections and the rising resistance to traditional antibiotics are the causes of the need for revolutionary antibiotics. Nanotechnology, a technique that employs materials featuring nanometer size, has grown in popularity for therapeutic uses and is very intriguing as a means of eradicating or limiting the activity of several pathogens. Silver nanoparticles have been shown to have antimicrobial properties against fungi and bacteria. The unique properties of silver nanoparticles, such as their high surface-area-to-volume ratio and the ability to release silver ions, can cause damage to the microbial cell membrane, interfere with cellular processes, and make them effective against a wide range of microorganisms. Synthesis of nanoparticles via natural products could potentiate their therapeutic activities. Moreover, phosphatase enzyme is also known to possess antimicrobial effects, and there is a fungus (Fusarium oxysporum) reported to have phosphatase enzymes in its extracellular fluid. Therefore, we focused on synthesizing silver nanoparticles by using extracellular proteins released by Fusarium oxysporum and thereafter evaluated its biological activities against pathogenic microbes. Our findings illustrated that synthesized nanoparticles showed prominent anti-microbicidal activities against various pathogenic bacterial and fungal species. Thus, these nanoparticles may be used against drug-resistant infections. Nanotechnology based on nanoscale materials is rapidly being used in clinical settings, particularly as a new approach for infectious illnesses. Recently, many physical/chemical approaches utilized to produce nanoparticles are expensive and highly unsafe to biological species and ecosystems. This study demonstrated an environmentally friendly mode of producing nanoparticles (NPs) where Fusarium oxysporum has been employed for generation of silver nanoparticles (AgNPs), which were further tested for their antimicrobial potentials against a variety of pathogenic microorganisms. The characterization of NPs was completed by UV–Vis spectroscopy, DLS and TEM, where it has been found that the NPs were mostly globular, with the size range of 50 to 100 nm. The myco-synthesized AgNPs showed prominent antibacterial potency observed as zone of inhibition of 2.6 mm, 1.8 mm, 1.5 mm, and 1.8 mm against Vibrio cholerae, Streptococcus pneumoniae, Klebsiella pneumoniae and Bacillus anthracis, respectively, at 100 µM. Similarly, at 200 µM for A. alternata, A. flavus and Trichoderma have shown zone of inhibition as 2.6 mm, 2.4 mm, and 2.1 mm, respectively. Moreover, SEM analysis of A. alternata confirmed the hyphal damage where the layers of membranes were torn off, and further EDX data analysis showed the presence of silver NPs, which might be responsible for hyphal damage. The potency of NPs may be related with the capping of fungal proteins that are produced extracellularly. Thus, these AgNPs may be used against pathogenic microbes and play a beneficial role against multi-drug resistance. [ABSTRACT FROM AUTHOR]

Detailed experimental and numerical investigations were carried out for evaluating the dynamic response of the stacked target plates toward moderate (100–250 m/s) velocity projectile impact. A single stage gas gun was utilized to launch the hemispherical and the blunt projectile toward two different hetro-stacked configurations (Al-St and St-Al). A comprehensive experimental (high speed 3D-DIC) and numerical (FE) evaluation was conducted to obtain the transient and post-impact behavior of the target plates. Influence of different projectile shapes on the full-field transient deformation profiles of different stacking configurations was studied in detail. Also, typical perforation parameters like plug size, shape, and perforation hole diameters were carefully measured and analyzed. A comprehensive error measure was utilized to quantify the similarity between the experimental and simulation results, a very good agreement was observed. [ABSTRACT FROM AUTHOR]

Bioplastics, synthesized by several microbes, accumulates inside cells under stress conditions as a storage material. Several microbial enzymes play a crucial role in their degradation. This research was carried to test the biodegradability of poly-β-hydroxybutyrate (PHB) utilizing PHB depolymerase, produced by bacteria isolated from sewage waste soil samples. Potent PHB degrader was screened based on the highest zone of hydrolysis followed by PHB depolymerase activity. Soil burial method was employed to check their degradation ability at different incubation periods of 15, 30, and 45 days at 37±2°C, pH 7.0 at 60% moisture with 1% microbial inoculum of Aeromonas caviae Kuk1-(34) (MN414252). Without optimized conditions, 85.76% of the total weight of the PHB film was degraded after 45 days. This degradation was confirmed with Fourier-transform infrared spectroscopy (FTIR) and Scanning electron microscope (SEM) analysis. The presence of bacterial colonies on the surface of the degraded film, along with crest, holes, surface erosion, and roughness, were visible. Media optimization was carried out in statistical mode using Plackett Burman (PB) and Central Composite Design (CCD) of Response Surface Methodology (RSM) by considering ten different factors. Analysis of Variance (ANOVA), Pareto chart, response surface plots, and F-value of 3.82 implies that the above statistical model was significant. The best production of PHB depolymerase enzyme (14.98 U/mL) was observed when strain Kuk1-(34) was grown in a media containing 0.1% PHB, K2HPO4 (1.6 gm/L) at 27 ℃ for seven days. Exploiting these statistically optimized conditions, the culture was found to be a suitable candidate for the management of solid waste, where 94.4% of the total weight of the PHB film was degraded after 45 days of incubation. [ABSTRACT FROM AUTHOR]

The study aimed to assess the proficiency of secondary metabolites (SMs) synthesized by actinobacteria isolated from the rhizospheric soil of Rauwolfia serpentina for its antimicrobial and anti-biofilm activity. After morphological and biochemical identification of actinobacteria, primary and secondary screening was done for specific metabolite production. The secondary metabolites were then tested for their antioxidant, antibacterial, and antibiofilm potential. Out of 29 bacterial colonies isolated, only one emerged as a novel isolate, Microbacterium LA2(R). Partial 16S rRNA gene sequence of the isolate LA2(R) was deposited in NCBI GenBank with accession number MN560041. The highest antioxidant capacity of the methanolic extract the novel isolate was found to be 474.183 µL AAE/mL and 319.037 µL AAE/mL by DPPH assay and ABTS assay respectively; three folds higher than the control. These results were further supported by the high total phenolic (194.95 gallic acid equivalents/mL) and flavonoid contents (332.79 µL quercetin equivalents/mL) of the methanolic extract. GC–MS analysis revealed the abundance of antibacterial compounds; where, n-Hexadecanoic acid was found to be the major compound present with a peak of 14 min retention time (RT) and 95% similarity index. MIC value of the metabolite was noted to be around 132.28 ± 84.48 μg/mL. The IC 50 value was found to be 74.37, 71.33, 66.28 and 84.48 μg/mL against Escherichia coli , Staphylococcus aureus , Klebsiella pneumonia , and Salmonella abony , respectively. Treatment with IC 50 of the extract decreased the biofilm formation up to 70%–80% against pathogenic strains viz. Escherichia coli , Staphylococcus aureus , Klebsiella pneumoniae and Salmonella abony. These significant activities of Microbacterium sp. LA2(R) suggests that it could be utilized for antibiotic production for human welfare and in various important industrial applications. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To determine the success rate of ultrasound guided hydrostatic reduction of intussusception using normal saline as an alternative to laparotomy. METHODS: This prospective cross-sectional study was conducted at Pediatric Surgery Department, Khyber Teaching Hospital, Peshawar from January-September 2018. Eighty patients aged between 3-24 months with clinical signs, symptoms and confirmatory sonographic evidence of intussusception were included in study. Procedure was carried out under ultrasound guidance using normal saline as medium for reduction. Maximum, three attempts were made each lasting 5-10 minutes. RESULTS: Mean age of patients was 11.9±4.8 months. Majority (n=60/80; 75%) of patients were males. Thirty-five percent of patients (n=28/80) presented on second day followed by 32.5% (n=26/80) on first day. Mean time for presentation was 2.1±0.9 days. Most common type of intussusception was Ileo-colic (n=72/80; 90%). Overall success rate was 82.5% (n=66/88). Success rate for patients presented within first day was 96.2% (n=25/26) as compared to 85.7% (n=24/28) in patients presented in 1-2 days and 65.3% (17/26) in patients presented after two days. Reduction time of intussusception ranged from 5-30 minutes with mean time of 17.5±1.4 minutes. In 76.3% (n=61/80) cases, intussusception was reduced within 20 minutes. In 14 (17.5%) patients, reduction could not be achieved (gangrenous gut=5, Meckel's diverticulum=3, illeo-ilial intussusception=1, perforation=5). Recurrence rate of intussusception was 7.5% (n=6/80), including 4 (5%) cases within 24 hours and 2 (2.5%) cases within 2 months after reduction. CONCLUSION: Ultrasound guided hydrostatic reduction of intussusception is an effective way to reduce intussusception, especially in patients presenting within two days. [ABSTRACT FROM AUTHOR]

In this paper, a novel methodology is proposed to reduce output voltage ripple (OVR) of the single-ended primary-inductor-converter (SEPIC). The mathematical analysis of the SEPIC converter is performed to compute suitable values of capacitance and switching frequency for optimal reduction in the OVR. The OVR in SEPIC converter is analyzed in the presence of two-dimensional effect: first by varying the values of the programmable capacitor using digital controller; second by changing the switching frequency of the switching signal. The comprehensive mathematical analysis of the OVR in SEPIC is performed for three modes. The obtained results of proposed methodology for the reduction of the OVR in SEPIC converter are verified through MATLAB simulation. [ABSTRACT FROM AUTHOR]