474 research outputs found
PWIDB: A framework for learning to classify imbalanced data streams with incremental data re-balancing technique
The performance of classification algorithms with highly imbalanced streaming data depends upon efficient balancing strategy. Some techniques of balancing strategy have been applied using static batch data to resolve the class imbalance problem, which is difficult if applied for massive data streams. In this paper, a new Piece-Wise Incremental Data re-Balancing (PWIDB) framework is proposed. The PWIDB framework combines automated balancing techniques using Racing Algorithm (RA) and incremental rebalancing technique. RA is an active learning approach capable of classifying imbalanced data and can provide a way to select an appropriate re-balancing technique with imbalanced data. In this paper, we have extended the capability of RA for handling imbalanced data streams in the proposed PWIDB framework. The PWIDB accumulates previous knowledge with increments of re-balanced data and captures the concept of the imbalanced instances. The PWIDB is an incremental streaming batch framework, which is suitable for learning with streaming imbalanced data. We compared the performance of PWIDB with a well-known FLORA technique. Experimental results show that the PWIDB framework exhibits an improved and stable performance compared to FLORA and accumulative re-balancing techniques
Bacterial contamination of Nigerian currency notes circulating within selected markets in Kaduna Metropolis
A study was carried out with the aim to assess the bacterial contamination of Nigerian currency notes circulating within selected markets in Kaduna Metropolis. A total of 80 samples of Nigerian currency notes of different denominations were randomly collected from Sabo, Kakuri, Kawo, Dattawa, U/rimi, Kasuwar Sati, Nassarawa, Chechenia, Kasuwar barci and Kasuwar Laraba markets in sterilized polythene bags The mean bacterial counts of the different currency notes were determined using standard microbiological methods. The types of bacteria associated with the currency notes and their frequency of occurrence were also determined using standard methods. The result of the study showed that lower denomination currencies had higher microbial loads, 22.65×104 ± 0.22×104 CFU/g for N100, 26.55×104 ± 0.45×104 CFU/g for N50, 20.95×104 ± 0.26×104 CFU/g for N20, 21.75×104 ± 0.35×104 CFU/g for N10 and 21.75×104 ± 0.12×104 CFU/g for N5 which were mostly obtained from Kakuri, Sabo, Nasarawa, and U/Rimi markets The species of bacteria isolated from the currencies were Staphylococcus aureus (52.2%), Escherichia coli (31.3%), Salmonella species (11.9%), and Proteus species (4.5%). Staphylococcus aureus was the most predominant bacteria isolated. This study revealed that currency notes collected from the markets within Kaduna Metropolis, were highly contaminated with different pathogenic bacteria thus, calls for public awareness on the potential risks associated with poor handling of currency notes at all levels.
Key words: Bacterial contamination, currency notes, selected markets, Kaduna Metropolis
 
Effects of shisha smoke inhalation on some long-term memory forms in adult male mice
Background: Shisha is a flavoured tobacco designed to be smoked in a water-pipe, but it effects on long-term memory has not been fully explored. This study was undertaken to evaluate the effect of Shisha smoke inhalation on some long-term memory models in adult male BALB/c mice.
Methods: Twenty male mice were divided into 4 groups of five mice each. Group I (control): fresh air; group II: exposed to bonged Shisha; group III: exposed to unbonged Shisha; group IV: exposed to activated charcoal smoke only. Each group was exposed for thirty minutes daily for seven weeks. Long-term memory was assessed using elevated plus maze (EPM), novel object recognition test (NORT) and Barnes maze (BM).
Results: There was statistically significant decrease (P<0.05) in novel object recognition in bonged Shisha group when compared with the control. There was statistically significant increase (P<0.05) in spatial learning and memory in bonged Shisha group when compared with control. There was statistically significant decrease (P<0.05) in acetylcholinesterase activity in bonged Shisha group when compared with control, but there was no statistically significant difference in anxiety related spatial memory in elevated plus maze when compared with the control. There was also increased in necrosis of hippocampal cells in bonged Shisha group and slight necrosis in unbonged and activated charcoal smoke when compared to control mice.
Conclusion: The outcomes of this study suggest that bonged Shisha smoke is neurotoxic to the brain because of combined effect of various toxicants emanating from different Shisha smoke constituents used in the set-up
Keywords: Shisha, Memory, Hippocampus, Acetylcholinesteras
Living HTA: automating health economic evaluation with R
Background: Requiring access to sensitive data can be a significant obstacle for the development of health models in the Health Economics & Outcomes Research (HEOR) setting. We demonstrate how health economic evaluation can be conducted with minimal transfer of data between parties, while automating reporting as new information becomes available.
Methods: We developed an automated analysis and reporting pipeline for health economic modelling and made the source code openly available on a GitHub repository. The pipeline consists of three parts: An economic model is constructed by the consultant using pseudo data. On the data-owner side, an application programming interface (API) is hosted on a server. This API hosts all sensitive data, so that data does not have to be provided to the consultant. An automated workflow is created, which calls the API, retrieves results, and generates a report.
Results: The application of modern data science tools and practices allows analyses of data without the need for direct access – negating the need to send sensitive data. In addition, the entire workflow can be largely automated: the analysis can be scheduled to run at defined time points (e.g. monthly), or when triggered by an event (e.g. an update to the underlying data or model code); results can be generated automatically and then be exported into a report. Documents no longer need to be revised manually.
Conclusions: This example demonstrates that it is possible, within a HEOR setting, to separate the health economic model from the data, and automate the main steps of the analysis pipeline
Bilosomes as a promising nanoplatform for oral delivery of an alkaloid nutraceutical:improved pharmacokinetic profile and snowballed hypoglycemic effect in diabetic rats
Diabetes mellitus is a life-threatening metabolic disease. At the moment, there is no effective treatment available to combat it. In this study, we aimed to develop berberine-loaded bilosomes (BER-BLS) to boost the oral bioavailability and therapeutic efficacy of berberine, a natural antidiabetic medication. The BER-BLS was fabricated using a thin-film hydration strategy and optimized using a central composite design (face-centered). The average vesicle size, entrapment efficiency, and surface charge of the optimized BER-BLS preparation were 196.5 nm, 89.7%, (−) 36.4 mV, respectively. In addition, it exhibited higher stability and better-sustained release of berberine than the berberine solution (BER-SOL). BER-BLS and BER-SOL were administered to streptozocin-induced diabetic rats. The optimized BER-BLS formulation had a significant hypoglycemic impact, with a maximum blood glucose decrease of 41%, whereas BER-SOL only reduced blood glucose by 19%. Furthermore, the pharmacological effect of oral BER-BLS and BER-SOL corresponded to 99.3% and 31.7%, respectively, when compared to subcutaneous insulin (1 IU). A pharmacokinetic analysis found a 6.4-fold rise in the relative bioavailability of berberine in BER-BLS when compared to BER-SOL at a dosage of 100 mg/kg body weight. Histopathological investigation revealed that BER-BLS is suitable for oral administration. Our data demonstrate that BLS is a potential nanocarrier for berberine administration, enhancing its oral bioavailability and antidiabetic activity
Influence of fibres on rheological properties and toughness of bituminous binder
Many studies have been made to examine different ways to modify bitumen and asphalt mixtures in response to increasing performance requirements. One of these is the use of additive materials and in this study, the potential of cellulose and glass fibres to modify the rheological properties of bitumen has been investigated. To achieve this, mixtures of bitumen with different contents of fibre were prepared and the properties of the bitumen and resulting modified binders were tested (penetration, softening point, viscosity and double edge notch tension test along with rheological testing in the dynamic shear rheometer). The experimental results demonstrated that adding fibres improves the rheological properties of bitumen across a range of loading frequencies and temperatures. Adding fibre reduced the penetration and increased the softening point and viscosity of bitumen implying improved rutting resistance of asphalt mixtures using these mastics. Finally this investigation established that adding fibre to bitumen improved its toughness, which could lead to improvement in asphalt fatigue performance. However, there are some limitations that are also discussed
A New Dental Superalloy System: V. Embrittling Phase Transformations
The σ phase is rich in Ta. When the Ta concentration is less than 14%, σ does not interfere with the slip mechanism; when the Ta concentration is more than 15%, σ interferes with the slip mechanism. The coherent α-Co 3Ta phase forms at Ta concentrations of less than 15%, whereas incoherent γ-Co 2Ta forms only at higher Ta concentrations. The interface between σ and the matrix is an important factor in the failure mechanism.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67929/2/10.1177_00220345740530013301.pd
Design of Frequency Reconfigurable Multiband Compact Antenna using two PIN diodes for WLAN/WiMAX Applications
YesIn this paper, we present a simple reconfigurable multiband antenna with two PIN diode switches for WiMAX/WLAN applications. The antenna permits reconfigurable switching in up to ten frequency bands between 2.2 GHz and 6 GHz, with relative impedance bandwidths of around 2.5% and 8%. The proposed antenna has been simulated using CST microwave studio software and fabricated on an FR-4 substrate. It is compact, with an area of 50 × 45 mm2, and has a slotted ground substrate. Both measured and simulated return loss characteristics of the optimized antenna show that it satisfies the requirement of 2.4/5.8 GHz WLAN and 3.5 GHz WiMAX antenna applications. Moreover, there is good agreement between the measured and simulated result in terms of radiation pattern and gain.Engineering and Physical Science Research Council through Grant EP/E022936A
Sodium and lithium incorporated cathode materials for energy storage applications - A focused review
The idea of lithium (Li)/sodium (Na) incorporated cathodes for both Li/Na-ion batteries has gained significant consideration throughout the past decade. The encouraging performance of various reported Li/Na incorporated cathode systems has the potential to review their exciting developments made so far to clearly understand the effect of numerous variables in improving the electrochemical performance. The current manuscript provides a focused review on the synthesis and electrochemical performance of these Li/Na incorporated cathode materials for Na/Li-ion batteries. Furthermore, the ruling mechanisms affecting the electrochemical performance of Li/Na incorporated cathode materials have been summarized. The majority of the synthesized Li/Na incorporated cathodes demonstrate good electrochemical cyclic stability, capacity retention, rate capability, charge/discharge capacity, etc. Li incorporated Na-based cathodes, show improved performance that can be attributed to the prevention of phase transformation at high voltages and loss of transition metal from the cathode. In the case of Na addition to Li-based cathodes, the Na pillaring effect significantly improves the Li interface layer stability, increases Li-ion diffusion, and retardation of Li and/or transition metal disordering. Various factors affecting the performance of Li/Na incorporated cathode families have been discussed that can be taken into account for development of future novel cathode materials demonstrating decent performance.The authors would like to acknowledge the financial support of Qatar University (QU) internal grant-QUCG-CENG-20/21-2. This publication was also made possible by NPRP Grant # NPRP11S-1225-170128 from Qatar National Research Fund (QNRF) (a member of the Qatar Foundation). Open Access funding provided by the Qatar National Library. Statements made here are the responsibility of the authors.Scopu
- …