HODGKIN-HUXLEY MODEL FOR ACTION POTENTIAL: MEMRISTIVE CHARACTERISTICS

poster abstractMemristor, a short for memory resistor, is the fourth ideal circuit element whose value varies as a function of charge that has passed through the de-vice. Voltage-gated ion channels in biological membranes share this charac-teristic of a memristor. In 1952, Hodgkin and Huxley (H-H) developed an electrical circuit model (HH model) to describe the time-dependent action potentials mediated by voltage-gated ion channels. We investigate the de-pendence of the action potential, including the onset of repeated spiking, on the applied current I, sodium and potassium channel conductance, and the membrane capacitance. We use a MATLAB code with the fourth-order Runge-Kutta method to solve the HH equations. Our results suggest that the memristive characteristics of the ion channels can be tuned over a wide range of parameters

CAN WE MAKE AN AXON FROM SEMICONDUCTOR MEMRISTORS?

poster abstractMemristor, a short for memory resistor, is the fourth fundamental circuit element whose instantaneous resistance depends not only on the voltage, but also on the history of the voltage applied to it. This recently discovered titanium dioxide thin film device has characteristics that are analogous to voltage-gated ion channels in biological membranes. In 1952, Alan Hodgkin and Andrew Huxley (HH) introduced an electrical circuit model that described the behavior of a neuron membrane. The electrical circuit consists of a capacitor which is due to phospholipid bilayer, three resistors that represent each ionic channel, and batteries that drive the ionic currents. The purpose of our research was to investigate the characteristics that are shared by both the biological membranes and the memristors. We introduce a minimal Hodgkin-Huxley model for DC applied stimulus in which the leakage channel, membrane capacitance, and potassium equilibrium voltage are absent. We conclude that spiking requires sodium and potassium channels in Hodgkin-Huxley model and, therefore, we predict that two or more distinct memristor species are necessary to mimic the electrical response of a neuron

Investing in the Future Nanos: IUPUI Nanotechnology Discovery Academy

poster abstractNanotechnology is a rapidly advancing field that is being applied to many aspects of everyday life. Consequently, it has become crucial to increase the general population’s understanding of nanotechnology and its application. To accomplish this, STEMCorp at IUPUI has been assisting INDA with week long summer camps that work to increase high school student’s awareness and understanding of nanotechnology. The camp consists of a morning seminars, afternoon lab activities, lab tour, and end-of-camp poster presentation. Lab tours focus on showing participants the practical applications of nanotechnology and exposes them to nanotechnology research occurring in Indianapolis. Afternoon lab activities immerse the students in a hands-on application of nanotechnology, providing a deeper understanding of the concepts introduced in the morning seminars. To assess the effectiveness of the INDA Nanotechnology summer camp, students were given pre- and post-assessment surveys to measure their interest in, and understanding of nanotechnology and STEM fields. Additionally, groups of students were selected for interviews and focus groups to provide a more in-depth understanding of their experience. From these data, it was found that the summer camp was effective at increasing student’s interest in and understanding of nanotechnology. Additionally, the student interviews/focus groups identified crucial components to this success

Nanotechnology STEM Program via Research Experience for High School Teachers

In this work, we report the outcomes from the IUPUI STEM outreach program “STEMCorp” that inspires high school students to pursue STEM majors. The STEMCorp program was modeled after the Multidisciplinary Undergraduate Research Initiative (MURI) at IUPUI. MURI research program introduces undergraduate students from at least two different departments with mentors from different disciplines to address research issues that may compose both engineering and sciences. The STEMCorp program brings undergraduate students to work with faculty and high school teachers to create a positive impact in enriching the high school students by introducing them to engineering and science with emphasis on nanotechnology for future careers. The program describes the collaborative activities between faculty, undergraduate students and high school STEM teachers in the creation of project-based, student-centered learning modules in the field of nanotechnology. The paper details the activities of the STEMCorp participants including their experiences in developing working partnerships and creating and implementing learning modules in the designated high school courses. The success of the program is assessed by the measurable outcomes of high school students' research projects. Specifically, two different learning modules are presented, including the processes used in the development of these modules and their outcomes. The collaborative research discussions between the faculty, undergraduate students, and high school teachers are detailed, covering research methodologies, hypothesis, and expected outcomes

Knowledge & Awareness about COVID-19 and the Practice of Respiratory Hygiene and Other Preventive Measures among Patients with Diabetes Mellitus in Pakistan

COVID-19 is a global pandemic that has emerged and it is rapidly spreading throughout the world and subsequently causing great damage to the global economy and health-care. Patients with diabetes or other comorbidities are at a greater risk of developing severe illness. Knowledge and awareness are key elements to stimulate practice of preventive measures. The present study evaluated the level of knowledge and awareness about COVID-19 among individuals with diabetes and their compliance with the preventive measures against it. A total of 242 individuals who were diagnosed with diabetes mellitus and were 18 years or older participated in the study. The data was collected using an interview based questionnaire. Data was analyzed using Statistical Package for Social Sciences(SPSS) version 24. The mean age ± SD of the study population was 50.78 ± 11.24 years. In this study, 215 (88.8%) participants were aware that COVID-19 is caused by a virus and the disease is spread through droplets after sneezing or touching and shaking hands with an infected person (78.5%). However, only half the study populace regularly monitored their glucose level and complied with the “sick day rules” that is applicable during this pandemic. The present study indicates that despite the adequate knowledge and awareness about the coronavirus disease, the study participants were non-compliant with the practice of preventive and precautionary measures against the pandemic

Verarbeitung bistatischer SAR-Daten

The interest in bistatic SAR processing has increased tremendously over the years. It is not only a useful advancement of monostatic SAR but offers considerable flexibility in designing SAR mission, improves classification and detection of objects in SAR images, provides additional information about the observed scene, reduces vulnerability in mili-tary applications, etc. Besides all these advantages, a bistatic SAR configuration offers a complex geometry with increased processing complexities. In order to achieve a computationally efficient processing approach, a frequency domain processor has been considered in this thesis for different bistatic SAR configurations. As a first step, the corresponding bistatic point target reference spectrum has been de-rived. Based on this spectrum an appropriate focusing algorithm is implemented. It is then used to focus both simulated and real bistatic SAR data for various bistatic SAR configurations. The results obtained using frequency domain algorithm, are compared with those obtained using a time domain (back projection) algorithm. A detailed analysis of the data shows that the frequency domain processor provides very good quality images.Das Interesse an bistatischer SAR-Verarbeitung ist in den letzten Jahren enorm gestie-gen. Es ist nicht nur eine sinnvolle Weiterentwicklung des monostatischen SAR sondern bietet ein hohes Maß an Flexibilität in der Entwicklung neuer SAR-Missionen, verbes-serte Klassifizierung und Entdeckung von Objekten in SAR-Bildern, liefert weitere In-formationen über die zu beobachtende Szene, reduziert die Entdeckungswahrschein-lichkeit der Trägerplatform in militärischen Anwendungen usw. Neben all diesen Vor-teilen führt eine bistatischen SAR-Konfiguration eine komplexere Geometrie mit erhöh-ter Verarbeitungskomplexität herbei, als es beim monostatischen SAR der Fall ist. Um eine rechentechnisch effiziente Verarbeitung zu erreichen, wurde ein Frequenzbe-reichsprozessor für verschiedene bistatischen SAR-Konfigurationen in dieser Arbeit entwickelt. Als erster Schritt wurde das bistatischen Punktziel Referenzspektrum herge-leitet. Basierend auf diesem Spektrum wurde ein entsprechender Fokussierungsalgo-rithmus implementiert. Die Verifizierung erfolg mit realen und simulierten bistatischen SAR-Daten für verschiedene bistatische SAR Konstellationen. Die Ergebnisse des Fre-quenzbereichsalgorithmus wurden mit denen einer Zeitbereichsmethode (Rückprojektionalgorithmus) verglichen. Eine detailierte Analyse zeigt, dass der herge-leitete Frequenzbereichsprozessor sehr gute Fokussierungsergebnisse liefert

INTRODUCTION A National park is an area set aside by a national government for the preservation of the natural environment. The World Conservation Union defines a National park as a natural area designated to protect the ecological integrity of one or more ecosystems for present and future generations. In Pakistan, the earlier ecological studies were generally observational. The earlier studies, generally appeared in 1950’s, were confined to visual description of the vegetation, and no attempts were made to recognize community types and to correlate them with the relevant environmental factors. On the contrary, advanced multivariate techniques of ordination and cluster analysis had been routinely used in Europe and other parts of the world. There are numerous ordination methods accessible in plant bionetwork, some of which have been extensively used, e.g. Principal Component Analysis (PCA) and Detrended Correspondence Analysis (DCA) (Hill & Gauch, 1980), whereas some others only sporadically used (Zhang, 2004). A series of studies using different ordination techniques were carried out in Pakistan by Ahmad et al., 2009; Ahmad, 2009; Jabeen & Ahmad, 2009; Pirzada et al., 2009; Ahmad et al., 2010a, b; Ahmad, 2011. In Canonical Correspondence Analysis (CCA) the floristic statistics and the environmental variables can be assimilated within the ordination (Kashian et al., 2003). Within the Ayubia National Park, the study area was the moist temperate forest in Rawalpindi, NE-Pakistan (Fig. 1), showing a high diversity of susceptible plant and animal species. The geographical location of the park is 330° 52' N and 730° 90' E (Farooque, 2002). The aim of this research was to quantify the vegetation in Ayubia National Park using ordination techniques and to determine the soilvegetation relationship to provide basic awareness for preservation of nationally significant native flora. A list of plant species present in the study area is provided in Table 1. Apart from their importance from ecological point of view few species are used as medicinal herbs by local inhabitants. Observed biodiversity of occuring species indicate that this area can be used for conservation of native flora. Exploring the vegetation dynamics and community assemblage in Ayubia National Park, Rawalpindi, Pakistan, using CCA

The relationship between species diversity and overall community assemblage was identified in two differentzones in Ayubia National Park (Rawalpindi, NE-Pakistan) which is recognized as protected area. CanonicalCorrespondence Analysis (CCA) was used to find correlation of environmental variables with speciesabundance/richness. Results showed that in Zone 1 species were rather scattered due to the less availability oforganic matter and soil moisture as they occupy the less dense forest cover. Whereas Zone 2 showed theopposite trends. Finally the overall zones showed that maximum number of quadrats included Zone 2 speciesdue to a great forest cover with excess amount of organic matter and soil moisture. The study highlighted theimportance of dynamic nature and composition of vegetation and stressed the need of conservation of nativeflora for future generations