Silver is a poisonous but precious heavy metal that has widespread application in various biomedical and environmental divisions. Wide-ranging usage of the metal has twisted severe environmental ...apprehensions. Henceforth there is a cumulative call for the progress of modest, low-cost and, the ecological method for remediation of silver. In the present study, Bacillus cereus was isolated from contaminated soil. Various experimental factors like the amount of AgNO
, inoculum size, temperature, time, and pH were improved by using central composite design (CCD) grounded on response surface methodology (RSM). Optimized values for AgNO
(1 mM) 10 ml, inoculum size (Bacillus cereus) 8.7 ml, temperature 48.5 °C, time 69 h, and pH 9 showed in the form of optimized ramps. The formed nanoparticles stayed characterized by UV-visible spectrophotometer, Scanning Electron Microscopy, Fourier transform infra-red spectrometry, particle size analyzer, and X-ray diffraction. The particle size ranges from 5 to 7.06 nm with spherical form. The antimicrobial effectiveness of synthesized nanoparticles was tested contrary to five multidrug resistant microbial strains, Staphylococcus epidermidis, Staphylococcus aureus, Escherichia coli, Salmonella enterica, Porteus mirabilis by disc diffusion method. The minimum inhibitory concentrations and minimum lethal concentrations were detected by the broth macro dilution method. 2,2-diphenyl-1-picrylhydrazyl-hydrate (DPPH) was used to check the free radical scavenging ability of biogenic silver nanoparticles. Similarly, anti-radical activity was checked by 2,2'-Azino-Bis-3-Ethylbenzothiazoline-6-Sulfonic Acid (ABTS) with varying time intervals. Catalytic potential of biosynthesized silver nanoparticles was also investigated.
The need for improved methods of hemorrhage control and resuscitation has resulted in a reappraisal of resuscitative endovascular balloon occlusion of the aorta (REBOA). However, there is a paucity ...of data regarding the use of REBOA on a multi-institutional level in the United States.
To evaluate the outcomes in trauma patients after REBOA placement.
A case-control retrospective analysis was performed of the 2015-2016 American College of Surgeons Trauma Quality Improvement Program data set, a national multi-institutional database of trauma patients in the United States. A total of 593 818 adult trauma patients (aged ≥18 years) were analyzed and 420 patients were matched and included in the study; patients who were dead on arrival or were transferred from other facilities were excluded. Trauma patients who underwent REBOA placement in the ED were identified and matched with a similar cohort of patients (the no-REBOA group). Both groups were matched in a 1:2 ratio using propensity score matching for demographics, vital signs, mechanism of injury, injury severity score, head abbreviated injury scale score, each body region abbreviated injury scale score, pelvic fractures, lower extremity vascular injuries and fractures, and number and grades of intra-abdominal solid organ injuries.
Outcome measures were the rates of complications and mortality.
Of 593 818 trauma patients, 420 patients (the REBOA group, 140 patients; 36 women and 104 men; mean SD age, 44 20 years; the no-REBOA group, 280 patients; 77 women and 203 men; mean SD age, 43 19 years) were matched and included in the analysis. Among the REBOA group, median injury severity score was 29 (interquartile range IQR, 18-38) and 129 patients (92.1%) had a blunt mechanism of injury. There was no significant difference between groups in median 4-hour blood transfusion (REBOA: packed red blood cells, 6 U IQR, 3-8 U; platelets, 4 U IQR, 3-9 U, and plasma, 3 U IQR, 2-5 U; and no-REBOA: packed red blood cells, 7 U IQR, 3-9 U; platelets, 4 U IQR, 3-8 U, and plasma, 3 U IQR, 2-6 U) or 24-hour blood transfusion (REBOA: packed red blood cells, 9 U IQR, 5-20 U; platelets, 7 U IQR, 3-13 U, and plasma, 9 U IQR, 6-20 U; and no-REBOA: packed red blood cells, 10 U IQR, 4-21 U; platelets, 8 U IQR, 3-12 U, and plasma, 10 U IQR, 7-20 U), median hospital length of stay (REBOA, 8 days IQR, 1-20 days; and no-REBOA, 10 days IQR, 5-22 days), or median intensive care unit length of stay (REBOA, 5 days IQR, 2-14 days; and no-REBOA, 6 days IQR, 3-15 days). The mortality rate was higher in the REBOA group as compared with the no-REBOA group (50 35.7% vs 53 18.9%; P = .01). Patients who underwent REBOA placement were also more likely to develop acute kidney injury (15 10.7% vs 9 3.2%; P = .02) and more likely to undergo lower extremity amputation (5 3.6% vs 2 0.7%; P = .04).
Placement of REBOA in severely injured trauma patients was associated with a higher mortality rate compared with a similar cohort of patients with no placement of REBOA. Patients in the REBOA group also had higher rates of acute kidney injury and lower leg amputations. There is a need for a concerted effort to clearly define when and in which patient population REBOA has benefit.
Wireless sensor network (WSN)-based Internet of Things (IoT) applications suffer from issues including limited battery capacity, frequent disconnections due to multi-hop communication and a shorter ...transmission range. Clustering and routing are treated separately in different solutions and, therefore, efficient solutions in terms of energy consumption and network lifetime could not be provided. This work focuses data collection from IoT-nodes distributed in an area and connected through WSN. We address two interlinked issues, clustering and routing, for large-scale IoT-based WSN and propose an improved clustering and routing protocol to jointly solve both of these issues. Improved clustering and routing provide area-based clustering derived from the transmission range of network nodes. During process of clustering, cluster-heads are selected in such a way that provide fail-over-proof routing. An efficient routing path is achieved by finding the minimal hop-count with the availability of alternate routing paths. The results are compared with state-of-the-art benchmark protocols. Theoretical and simulation results demonstrate reliable network topology, improved network lifetime, efficient node density management and improved overall network capacity.
Previous studies have linked public-sector employees’ motivation to desired results such as higher performance and improved quality of public services. However, questions about the impact of employee ...motivation on public projects have received less attention. This article uses work motivation theory to explore the fundamental processes by which transformational leadership (TL) and public service motivation (PSM) engender public project success (PS). Analysis of 296 public servants’ data working on Pakistan public projects showed a positive correlation between TL, PSM, and PS. It also showed that PSM partially mediates the relationship between TL and PS.
The aim of research work is to characterize hyperelastic material and to determine a suitable strain energy function (SEF) for an indigenously developed rubber to be used in flexible joint use for ...thrust vectoring of solid rocket motor. In order to evaluate appropriate SEF uniaxial and volumetric tests along with equi-biaxial and planar shear tests were conducted. Digital image correlation (DIC) technique was utilized to have strain measurements for biaxial and planar specimens to input stress-strain data in Abaqus(R). Yeoh model seems to be right choice, among the available material models, because of its ability to match experimental stress-strain data at small and large strain values. Quadlap specimen test was performed to validate material model fitted from test data. FE simulations were carried out to verify the behavior as predicted by Yeoh model and results are found to be in good agreement with the experimental data.
Inferior mechanical properties are hindering the growth of using natural fibre reinforced polymeric composites in many structural applications. One of the popular solutions to this issue being ...reported in the literature is the addition of nano or micro reinforcements such as carbon nanotubes, ceramic particles, glass particles, clay, rubber additive etc., which is expensive. Furthermore, questions are raised over biodegradability of said composites. The current study investigated the effect of micro-crystalline cellulose (MCC) particles and alkaline treatment on the tensile, bending and impact properties of jute woven fabric reinforced bio-epoxy composite. The composite samples were made by compression moulding using manufacturer provided curing conditions. Alkaline treatment of jute fabric was found to have positive relationships with tensile and flexural properties, whereas it had negative with the impact strength of bio-composite. It is found that up to 7% addition of MCC particles, tensile, bending and charpy impact strength were improved by 48%, 52% and 100% respectively. Beyond this percentage, the mechanical properties were found to be deteriorated.
Different auxetic structures and auxetic phenomena are continuously explored by researchers in the field of textiles with enhanced properties for broader application areas. However, developing ...three-dimensional (3D) auxetic structures by using weaving technology is a real challenge compared to knitting and non-weaving techniques. This research work reports a novel approach to develop 3D woven structures with in-plane auxetic behavior. A conventional 3D multilayer orthogonal through-the-thickness structure was converted into a 3D auxetic woven structure. The structure was designed with three different yarn components to incorporate auxetic geometry. One type of yarn was used in the warp direction, while the other two-yarn systems, comprised of fine elastic yarn and coarse binding yarn, were used in the weft direction. The auxetic geometry achieved resembles the reentrant hexagon by the unusual arrangement of warp yarns. For an in-depth study of the structure, nine fabric samples were fabricated by using a conventional semi-automatic weaving machine with four different influencing parameters. The developed samples were then tested on a tensile testing machine to evaluate their mechanical and auxetic behavior. The results show that the 3D fabrics have a negative Poisson’s ratio (NPR) even at higher tensile strain and that the appropriate binding to the warp yarn diameter can produce a higher NPR. In addition, the repeat size of the elastic weft yarn, bending stiffness of the binding yarn, and stretch percentage of the elastic weft yarn can highly affect the NPR of the fabric. Furthermore, among all the 3D woven fabrics developed with different structural parameters, the maximum NPR achieved was –1.61.
Internet of Things (IoT) devices are well-connected; they generate and consume data which involves transmission of data back and forth among various devices. Ensuring security of the data is a ...critical challenge as far as IoT is concerned. Since IoT devices are inherently low-power and do not require a lot of compute power, a Network Intrusion Detection System is typically employed to detect and remove malicious packets from entering the network. In the same context, we propose feature clusters in terms of Flow, Message Queuing Telemetry Transport (MQTT) and Transmission Control Protocol (TCP) by using features in UNSW-NB15 data-set. We eliminate problems like over-fitting, curse of dimensionality and imbalance in the data-set. We apply supervised Machine Learning (ML) algorithms, i.e., Random Forest (RF), Support Vector Machine and Artificial Neural Networks on the clusters. Using RF, we, respectively, achieve 98.67% and 97.37% of accuracy in binary and multi-class classification. In clusters based techniques, we achieved 96.96%, 91.4% and 97.54% of classification accuracy by using RF on Flow & MQTT features, TCP features and top features from both clusters. Moreover, we show that the proposed feature clusters provide higher accuracy and requires lesser training time as compared to other state-of-the-art supervised ML-based approaches.
Abstract
The data quality of low-cost sensors has received considerable attention and has also led to PM
2.5
warnings. However, the calibration of low-cost sensor measurements in an environment with ...high relative humidity is critical. This study proposes an efficient calibration and mapping approach based on real-time spatial model. The study carried out spatial calibration, which automatically collected measurements of low-cost sensors and the regulatory stations, and investigated the spatial varying pattern of the calibrated low-cost sensor data. The low-cost PM
2.5
sensors are spatially calibrated based on reference-grade measurements at regulatory stations. Results showed that the proposed spatial regression approach can explain the variability of the biases from the low-cost sensors with an R-square value of 0.94. The spatial calibration and mapping algorithm can improve the bias and decrease to 39% of the RMSE when compared to the nonspatial calibration model. This spatial calibration and real-time mapping approach provide a useful way for local communities and governmental agencies to adjust the consistency of the sensor network for improved air quality monitoring and assessment.
Abstract
Stripe rust (caused
by Puccinia striiformis tritici
) is one of the most devastating diseases of wheat. The most effective ways to control stripe rust are the use of resistant cultivars and ...the timely use of an appropriate dose of fungicide. However, the changing nature of rust pathogen outwits the use of resistant cultivars, and the use of a fungicide is associated with environmental problems. To control the disease without sacrificing the environment, we screened 16 endophytic bacteria, which were isolated from stripe rust-resistant wheat cultivars in our previous study, for their biocontrol potential. A total of 5 bacterial strains
Serratia marcescens
3A,
Bacillus megaterium
6A,
Paneibacillus xylanexedens
7A,
Bacillus subtilis
11A, and
Staphyloccus agentis
15A showed significant inhibition of
Puccinia striiformis
f. sp.
tritici
(Pst) urediniospores germination. Two formulations i.e., fermented liquid with bacterial cell (FLBC) and fermented liquid without bacterial cells (FL) of each bacterial strain, were evaluated against the urediniospores germination. Formulations of five selected endophytic bacteria strains significantly inhibited the uredinioospores germination in the lab experiments. It was further confirmed on seedlings of Pakistani susceptible wheat cultivar Inqilab-91 in the greenhouse, as well as in semi-field conditions. FLBC and FL formulations applied 24 h before
Pst
inoculation (hbi) displayed a protective mode. The efficacy of FLBC was between 34.45 and 87.77%, while the efficacy of FL was between 39.27 and 85.16% when applied 24 hbi. The inoculated wheat cultivar Inqilab-91 was also tested under semi-field conditions during the 2017–2018 cropping season at the adult plant stage. The strains
Bacillus megaterium
6A and
Paneibacillus xylanexedens
7A alone significantly reduced the disease severity of stripe rust with the efficacy of 65.16% and 61.11% for the FLBC in protective effect, while 46.07% and 44.47% in curative effect, respectively. Inoculated seedlings of Inqilab-91 showed higher activities of antioxidant enzymes, superoxide dismutase (SOD), peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL). The treated seedlings also showed higher expressions of pathogenesis-related (PR) protein genes, antifungal protein (PR-1), β-1,3-endoglucanases (PR-2), endochitinases (PR-4), peroxidase (PR-9), and ribonuclease-like proteins (PR-10). These results indicated that endophytic bacteria have the biocontrol potential, which can be used to manage stripe rust disease. High production antioxidant enzymes, as well as high expression of PR protein genes, might be crucial in triggering the host defense mechanism against
Pst
.
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