In vitro Effects of Two Silver Electrodes on Select Wound Pathogens

The use of electrical current to promote wound healing is well documented. However, little is understood about the effects of micro-amperage direct current (μADC) on growth of wound pathogens. The purpose of this project was to investigate the antibacterial effects of a silver wire/silver nylon electrode carrying μADC in vitro on several Gram positive and Gram negative bacteria. The current was delivered via silver wire and silver nylon electrodes at an amplitude of 100 μA for a 30-minute duration in an in vitro system. Results demonstrated that only silver wire carrying current inhibited bacterial growth around the anode. In contrast, the silver nylon electrode with or without current exhibited antibacterial activity around both the anode and cathode. The results of this study provide convincing evidence that the silver ion (AG+) is responsible for suppressing bacterial growth. Both silver electrodes were bactericidal with all Gram negative bacteria tested and bacteriostatis with most Gram positive bacteria tested, suggesting that the cell wall composition may be a determining factor in the effectiveness of the AG+

Antibacterial Effects of a Silver Electrode Carrying Microamperage Direct Current in vitro

Currently, electrical stimulation is an accepted method used clinically to promote chronic wound healing. A literature review revealed that similar therapeutic current has been shown to suppress growth of common wound pathogens in vitro and in vivo. To date, little has been reported on the factors contributing to the antibacterial effects of microamperage direct current (μADC) stimulation. The purpose of this project was to investigate the role of electric field strength, current density, pH, and type of electrode used in vitro, to gain a better understanding of how these factors contribute to inhibiting growth of select wound pathogens. μADC was applied via silver electrodes at amplitudes ranging from 26 μA to 800 μA in an in vitro system consisting of Staphylococcus aureus and Pseudomonas aeruginosa. Results suggest that transmission of μADC by silver wire inhibits bacterial growth around the anode, and that the area of inhibition is directly proportional to the size of the electrode used. Current amplitude (as a function of electric field strength and current density) and pH did not seem to cause the antibacterial effects observed in this study

Multimodal biometrics score level fusion using non-confidence information

Multimodal biometrics refers to automatic authentication methods that depend on multiple modalities of measurable physical characteristics. It alleviates most of the restrictions of single biometrics. To combine the multimodal biometrics scores, three different categories of fusion approaches including rule based, classification based and density based approaches are available. When choosing an approach, one has to consider not only the fusion performance, but also system requirements and other circumstances. In the context of verification, classification errors arise from samples in the overlapping region (or non- confidence region) between genuine users and impostors. In score space, a further separation of the samples outside the non-confidence region does not result in further verification improvements. Therefore, information contained in the non-confidence region might be useful for improving the fusion process. Up to this point, no attempts are reported in the literature that tries to enhance the fusion process using this additional information. In this work, the use of this information is explored in rule based and density based approaches mentioned above

Fostering community and belonging in diverse science backgrounds through reflective writing

Reflective writing and the practice of reflection helps build community and a sense of belonging for students from diverse science backgrounds. Reflection also helps students develop a deeper understanding of themselves to be more aware of their learning. In addition, reflection allows students to connect their personal insights, values, and cultural and lived experiences to material they are studying. More importantly, students connect with others, to promote a sense of relevance and meaning. By sharing their reflections with their peers, students discover commonalities, validate each other\u27s experiences, and create a supportive community of learning. In addition, reflective writing encourages students to consider different learning perspectives and to embrace diversity by being open to, and accepting and appreciating the differences among their peers. This inclusive mindset fosters a sense of belonging and community, where students recognize and value the contributions of others. This talk shares educator and student experiences on building a culture of belonging in a senior undergraduate biotechnology and business course. Since reflective journaling is typically not part of post-secondary science classes, students questioned the usefulness of this activity in the beginning of semester. However, by the end of the class most students\u27 reflective blogs changed and transformed, from talking about individual aspirations, to a collective goal. Students acknowledged and accepted other’s differences in values and learned to work together by embracing, instead of rejecting, each others\u27 differences. Reflective story-sharing and storytelling helped students break each other’s assumption and stereotype (usually from other disciplines) and begin to build a connected community of learning

Is there a need for a specific educational scholarship for using e-learning in medical education?

We propose the need for a specific educational scholarship when using e-learning in medical education. Effective e-learning has additional factors that require specific critical attention, including the design and delivery of e-learning. An important aspect is the recognition that e-learning is a complex intervention, with several interconnecting components that have to be aligned. This alignment requires an essential iterative development process with usability testing. Effectiveness of e-learning in one context may not be fully realized in another context unless there is further consideration of applicability and scalability. We recommend a participatory approach for an educational scholarship for using e-learning in medical education, such as by action research or design-based research

Short-term voiding patterns after vaginal hysterectomy and pelvic floor repair

Background: Post-operative transient voiding dysfunction is a known complication of vaginal hysterectomy (VH) with pelvic floor repair (PFR). This study aims to determine the duration of urinary catheterization prior to resumption of normal voiding and hospital length of stay for patients who have undergone VH, PFR with or without concomitant application of transvaginal mesh (TVM) and/or mid-urethral sling (MUS).Methods: This is a retrospective cohort study of women who underwent VH with PFR at a single urogynaecology centre in Singapore between 01 October 2016 and 30 September 2017. Patients’ files were reviewed for data collection and analysis.Results: A total of 238 women with VH with PFR were studied, of whom 68 (28.6%) did not have any implant, 60 (25.2%) had only TVM, 50 (21.0%) had only MUS, and 60 (25.2%) had both TVM and MUS. Overall, 1/68 (1.5%) patients without implants, 16/110 (14.5%) patients with one implant and 13/60 (21.7%) patients with two implants failed at least 1 inpatient voiding trial. Patients undergoing VH PFR without implants had shorter duration of catheterization compared to those with concomitant implants (2.2 versus 5.6 days, p<0.01). Duration of catheterization was shorter in patients with only MUS compared to patients with only TVM (3.5 versus 4.7 days, p<0.01). Patients with single implant had significantly shorter duration of catheterization compared to those with two implants (4.2 versus 5.6 days, p=0.001).Conclusions: One in 68 patients with VH with PFR without implants experienced short term voiding difficulties. This risk increased to 1 in 5 when concomitant implants were inserted

DC-Link Voltage Coordinated-Proportional Control for Cascaded Converter with Zero Steady-State Error and Reduced System Type

copyright 2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.Cascaded converter is formed by connecting two sub-converters together, sharing a common intermediate DC-link voltage. Regulation of this DC-link voltage is frequently realized with a Proportional-Integral (PI) controller, whose high gain at DC helps to force a zero steady-state tracking error. Such precise tracking is however at the expense of increasing the system type, caused by the extra pole at the origin introduced by the PI controller. The overall system may hence be tougher to control. To reduce the system type while preserving precise DC-link voltage tracking, this paper proposes a coordinated control scheme for the cascaded converter, which uses only a proportional DC-link voltage regulator. The resulting converter is thus dynamically faster, and when compared with the conventional PI-controlled converter, it is less affected by impedance interaction between its two sub-converters. The proposed scheme can be used with either unidirectional or bidirectional power flow, and has been verified by simulation and experimental results presented in the paper

Spatial analysis of falls in an urban community of Hong Kong

<p>Abstract</p> <p>Background</p> <p>Falls are an issue of great public health concern. This study focuses on outdoor falls within an urban community in Hong Kong. Urban environmental hazards are often place-specific and dependent upon the built features, landscape characteristics, and habitual activities. Therefore, falls must be examined with respect to local situations.</p> <p>Results</p> <p>This paper uses spatial analysis methods to map fall occurrences and examine possible environmental attributes of falls in an urban community of Hong Kong. The Nearest neighbour hierarchical (Nnh) and Standard Deviational Ellipse (SDE) techniques can offer additional insights about the circumstances and environmental factors that contribute to falls. The results affirm the multi-factorial nature of falls at specific locations and for selected groups of the population.</p> <p>Conclusion</p> <p>The techniques to detect hot spots of falls yield meaningful results that enable the identification of high risk locations. The combined use of descriptive and spatial analyses can be beneficial to policy makers because different preventive measures can be devised based on the types of environmental risk factors identified. The analyses are also important preludes to establishing research hypotheses for more focused studies.</p