Antiretroviral therapy of HIV infection using a novel optimal type-2 fuzzy control strategy

Abstract The human immunodeficiency virus (HIV), as one of the most hazardous viruses, causes destructive effects on the human bodies' immune system. Hence, an immense body of research has focused on developing antiretroviral therapies for HIV infection. In the current study, we propose a new control technique for a fractional-order HIV infection model. Firstly, a fractional model of the HIV model is investigated, and the importance of the fractional-order derivative in the modeling of the system is shown. Afterward, a type-2 fuzzy logic controller is proposed for antiretroviral therapy of HIV infection. The developed control scheme consists of two individual controllers and an aggregator. The optimal aggregator modifies the output of each individual controller. Simulations for two different strategies are conducted. In the first strategy, only reverse transcriptase inhibitor (RTI) is used, and the superiority of the proposed controller over a conventional fuzzy controller is demonstrated. Lastly, in the second strategy, both RTI and protease inhibitors (PI) are used simultaneously. In this case, an optimal type-2 fuzzy aggregator is also proposed to modify the output of the individual controllers based on optimal rules. Simulations results demonstrate the appropriate performance of the designed control scheme for the uncertain system

Patterns of injury and violence in Yaoundé Cameroon: an analysis of hospital data.

BackgroundInjuries are quickly becoming a leading cause of death globally, disproportionately affecting sub-Saharan Africa, where reports on the epidemiology of injuries are extremely limited. Reports on the patterns and frequency of injuries are available from Cameroon are also scarce. This study explores the patterns of trauma seen at the emergency ward of the busiest trauma center in Cameroon's capital city.Materials and methodsAdministrative records from January 1, 2007, through December 31, 2007, were retrospectively reviewed; information on age, gender, mechanism of injury, and outcome was abstracted for all trauma patients presenting to the emergency ward. Univariate analysis was performed to assess patterns of injuries in terms of mechanism, date, age, and gender. Bivariate analysis was used to explore potential relationships between demographic variables and mechanism of injury.ResultsA total of 6,234 injured people were seen at the Central Hospital of Yaoundé's emergency ward during the year 2007. Males comprised 71% of those injured, and the mean age of injured patients was 29 years (SD = 14.9). Nearly 60% of the injuries were due to road traffic accidents, 46% of which involved a pedestrian. Intentional injuries were the second most common mechanism of injury (22.5%), 55% of which involved unarmed assault. Patients injured in falls were more likely to be admitted to the hospital (p < 0.001), whereas patients suffering intentional injuries and bites were less likely to be hospitalized (p < 0.001). Males were significantly more likely to be admitted than females (p < 0.001)DiscussionPatterns in terms of age, gender, and mechanism of injury are similar to reports from other countries from the same geographic region, but the magnitude of cases reported is high for a single institution in an African city the size of Yaoundé. As the burden of disease is predicted to increase dramatically in sub-Saharan Africa, immediate efforts in prevention and treatment in Cameroon are strongly warranted

Magnetic force imaging and handling of cancer cells on the nanoscale

A thesis submitted to the University of Bedfordshire in partial fulfilment of the requirements for the degree of Doctor of PhilosophyCancer treatment has become one of the top priorities in health. Great efforts have been devoted to the diagnosis and therapy of cancers. Culturing cells with drugs is a common method used to investigate cancer therapy in experiments. However, this method has limitations in cancer treatment because of the lack of capabilities of handling cells, targeting specific cells and measuring the nanoscale changes in cell structures. Magnetic nanoparticles (MNPs) and magnetic force microscopes (MFMs) have been used to study biological samples due to their advantages in tracing, manipulating and measuring, which has motivated to research the method for implanting MNPs into cancer cells, to target the cancer cells and to measure their changes during the treatment. Research reported in this thesis focuses on magnetic force imaging and handling of targeted cancer cells on the nanoscale for possible new cancer therapies. A new differential MFM imaging method and a new compensation MFM imaging method were developed in this research to improve the MFM imaging quality. The former reverses the magnetized direction of probe from upward to downward and the latter scans the samples with three scanning directions of 0°, 45° and 90°. With these methods, the obtained MFM images achieve a high resolution, SNR, image contrast and accuracy. A pair of innovative MNPs picking up method and MNPs releasing method were developed in this research to achieve flexible MNPs picking up and releasing. The picking up method handles the magnetic tip following a helical structure as the capture path when approaching to the target MNPs. The MNPs releasing method uses a biaxiably-oriented polypropylene (BOPP) film together with a magnet allowing MNPs to separate from the MFM tip surface. With these methods, the target MNPs can be picked up by the MFM tip and released from the tip surface successfully. This research discovered, for the first time in the world to the author knowledge, the differences in morphological features (height, length, width and roughness) and mechanical properties (adhesive force and Young‟s modulus) between multinuclear and mononuclear colon cancer cells after treating the cells with fullerenol. This discovery provides guidance to the selection of cells for target treatment. The results indicate that the mononuclear SW480 cells are more sensitive to fullerenol than the multinuclear SW480 cells and the multinuclear SW480 cells exhibit a stronger drug-resistance than the mononuclear SW480 cells. A new MNPs implantation method was developed in this research, which enables the FITC-MNPs functioned tip to insert into cells so that MNPs are implanted into the target cells. Fluorescence microscope images show that the FITC-MNPs are released into the cells successfully. Cells being treated with MNPs (Cell-MNPs) manipulation III methods are explored by magnet and controllable electromagnets to manipulate the target cancer cells. The results show that the cell-MNPs have magnetic force manipulated capability and they can be manipulated to have the leftward, rightward, upward and downward flexibilities

Nanomechanics of Hierarchical Cellular Solids

Materials Science and Engineering, a young and vibrant discipline with its inception in the 1950s, has expanded into three directions: metals, polymers, and ceramics (and their mixtures, composites). Beyond the traditional scope, biological materials have drawn much attention since 1990s due to their optimal structures, which rise from hundreds of million years of evolution. Generally, biological materials are complex composites and possess varieties of hierarchical structures, multifunctionality, self-organization and self-assembly. From the point of view of mechanics, mechanical properties of natural (or biological) materials are outstanding, although their constituent materials are weak. This is because the necessary mechanical support is in great need due to their surrounding environment. Therefore, their efficiency provides us with useful indications as to how to synthesize new materials inspired by natural ones, and thus drives scientists and engineers to reveal the mechanisms behind the observed phenomena of interest. In this regard, the tendency in the design of novel materials apparently holds a promising future in new Material Science. To date, it is widely accepted that the research on biological materials is a multidisciplinary field including chemistry, physics, and biology etc. Although some progress has been already made, there is still a long way to go to mass fabricate bio-inspired materials. In this thesis, employing a "bottom-up" approach, we have devised three hierarchical models (2-D hierarchical woven, 2-D hierarchical honeycomb and 3-D hierarchical foam) inspired by structures found in natural materials and investigated their mechanical properties. The common characteristic of these structures is their being quasi-self-similar. Regarding the derivation of their mechanical properties, we consider the (n-1)th level structure to be a continuous medium and from it we calculate the mechanical properties of the nth level structure. In the first chapter, we introduce the motivation for this work. By reviewing the literature on both well-studied and less familiar natural materials, we summarize their structural characteristics and biomechanical mechanisms. Chapter 2 deals with our first model—1-D or 2-D hierarchical woven tissue, and the elastic anisotropy of the structure is derived, based on the well-known stiffness averaging method by volumes. In order to verify the theory, an experiment on leaves, which are modeled as one-dimensional hierarchical woven structures, is performed. Also, a comparison between theoretical predictions and experimental data on tendons from the literature is made. The considered structure could be used as a scaffold, which can provide the mechanical support and optimize tissue regeneration at each hierarchical level. Chapters 3-5 discuss our second model—2-D hierarchical honeycomb. Incorporating the surface effect, the in-plane linear-elastic properties, elastic buckling properties, fracture strength and toughness are derived. Chapter 3 examines the linear elastic properties and the stiffness efficiency thanks to the minimum-weight analysis, and the parametric analysis shows that the structure can be optimized. Chapter 4 discusses elastic buckling by employing the Euler buckling formula; besides local buckling, progressive buckling is also investigated. The progressive failure behavior is found to be similar to that of balsa wood. Strength efficiency is also illustrated. Employing "Quantized Fracture Mechanics" (Pugno, 2002; Pugno and Ruoff, 2004), Chapter 5 modifies the classical strength formulas of the conventional honeycomb and investigates the defective hierarchical honeycomb; the fracture toughness of the perfect and defective hierarchical honeycomb are both derived. In general, hierarchical honeycombs can be used as energy-absorbing materials and bioscaffolds for directional tissue regeneration. Chapter 6 models our third hierarchical structure—3-D hierarchical foam. The Young's modulus and plastic strength are derived based on structural analysis. When the characteristic size of the lowest level is very small (less than 10nm), surface effects play an important role in determining the mechanical properties of the structure. The hierarchical foam could be used as nano-porous gold. Chapter 7 provides conclusions and an outlook for future wor

Cell Mechanics in Physiology: A Force Based Approach

All biological systems rely on complex interactions with their external and internal environments where the key factors are force sensing and force generation. These systems are highly dynamic, and recent studies have shown that it is the control and maintenance of these interactions that are essential for normal functioning. Appreciation of these roles has led to a revolution in instrumentation and techniques to study and model mechanical interaction at all length and time scales in biology. The work presented here is one such effort, utilizing a magnetics based force system to study and understand the mechanisms of cell mechanics and their role in mucuciliary clearance in the lung and in cancer cell invasion and metastasis. I first introduce the instrumentation and describe basic rheological concepts that govern the study of cell mechanics. I then report on the application of this system to study the force generation and dynamics of airway cilia. The bulk of the work is focussed on the role of cytoskeleton mechanics in cancer. I present our results which show the remarkable relationship between the cell's mechanical properties and its metastatic potential. Finally, I report on a novel pathway which is responsible for force mediated sensing in cells and show that this pathway is deregulated in cancer. These results have strong implications on the potential of stiffness and force sensing pathways as novel cancer therapeutic targets

A Novel Flexible and Steerable Probe for Minimally Invasive Soft Tissue Intervention

Current trends in surgical intervention favour a minimally invasive (MI) approach, in which complex procedures are performed through increasingly small incisions. Specifically, in neurosurgery, there is a need for minimally invasive keyhole access, which conflicts with the lack of maneuverability of conventional rigid instruments. In an attempt to address this fundamental shortcoming, this thesis describes the concept design, implementation and experimental validation of a novel flexible and steerable probe, named “STING” (Soft Tissue Intervention and Neurosurgical Guide), which is able to steer along curvilinear trajectories within a compliant medium. The underlying mechanism of motion of the flexible probe, based on the reciprocal movement of interlocked probe segments, is biologically inspired and was designed around the unique features of the ovipositor of certain parasitic wasps. Such insects are able to lay eggs by penetrating different kinds of “host” (e.g. wood, larva) with a very thin and flexible multi-part channel, thanks to a micro-toothed surface topography, coupled with a reciprocating “push and pull” motion of each segment. This thesis starts by exploring these foundations, where the “microtexturing” of the surface of a rigid probe prototype is shown to facilitate probe insertion into soft tissue (porcine brain), while gaining tissue purchase when the probe is tensioned outwards. Based on these findings, forward motion into soft tissue via a reciprocating mechanism is then demonstrated through a focused set of experimental trials in gelatine and agar gel. A flexible probe prototype (10 mm diameter), composed of four interconnected segments, is then presented and shown to be able to steer in a brain-like material along multiple curvilinear trajectories on a plane. The geometry and certain key features of the probe are optimised through finite element models, and a suitable actuation strategy is proposed, where the approach vector of the tip is found to be a function of the offset between interlocked segments. This concept of a “programmable bevel”, which enables the steering angle to be chosen with virtually infinite resolution, represents a world-first in percutaneous soft tissue surgery. The thesis concludes with a description of the integration and validation of a fully functional prototype within a larger neurosurgical robotic suite (EU FP7 ROBOCAST), which is followed by a summary of the corresponding implications for future work

Mastering Endo-Laparoscopic and Thoracoscopic Surgery

This is an open access book. The book focuses mainly on the surgical technique, OR setup, equipments and devices necessary in minimally invasive surgery (MIS). It serves as a compendium of endolaparoscopic surgical procedures. It is an official publication of the Endoscopic and Laparoscopic Surgeons of Asia (ELSA). The book includes various sections covering basic skills set, devices, equipments, OR setup, procedures by area. Each chapter cover introduction, indications and contraindications, pre-operative patient’s assessment and preparation, OT setup (instrumentation required, patient’s position, etc.), step by step description of surgical procedures, management of complications, post-operative care. It includes original illustrations for better understanding and visualization of specific procedures. The book serves as a practical guide for surgical residents, surgical trainees, surgical fellows, junior surgeons, surgical consultants and anyone interested in MIS. It covers most of the basic and advanced laparoscopic and thoracoscopic surgery procedures meeting the curriculum and examination requirements of the residents

Klipsun Magazine, 2006, Volume 37, Issue 01 - September

I can still remember how eager I was to come to college my first quarter at Western four years ago. I don\u27t think I slept more than a few hours the night before. Not because I was scared, and not because I was nervous. It was because I couldn\u27t wait to explore life through the eyes of a college student. I didn\u27t believe people when they said it would go by fast. Four years seems like a long time to an 18- year-old. Well it isn\u27t. I can\u27t help but feel excited when I think that the stories in this issue of Klipsun might help others live life a little more fully during their time in Bellingham. Sneak a peak at Northwest culture in Hop- Head Nation. Learn how some locals use Bellingham\u27s natural structures as their own personal jungle-gyms in Hard-Rock Getaway or discover what those barefoot people balancing on an inch or so of rope at Boulevard Park are up to in Walk the Slack Line. If you can\u27t find a story that grabs your attention in the magazine, then I encourage you to peruse the selection online at klipsun.wwu.edu. There, you might find longboarding is the mode of transportation for you in Kick, Push and Coast. Or you might decide that the multimedia presentation of one writer\u27s experience in «l Skydiving with Doctor Death is an experience worth having. I\u27ve graduated now, and I have one piece of advice for you. Live your life with no regrets. Appreciate the now and don\u27t look back. I hope you find something that catches your attention in this issue. Thanks for reading.https://cedar.wwu.edu/klipsun_magazine/1238/thumbnail.jp

Mastering Endo-Laparoscopic and Thoracoscopic Surgery

This is an open access book. The book focuses mainly on the surgical technique, OR setup, equipments and devices necessary in minimally invasive surgery (MIS). It serves as a compendium of endolaparoscopic surgical procedures. It is an official publication of the Endoscopic and Laparoscopic Surgeons of Asia (ELSA). The book includes various sections covering basic skills set, devices, equipments, OR setup, procedures by area. Each chapter cover introduction, indications and contraindications, pre-operative patient’s assessment and preparation, OT setup (instrumentation required, patient’s position, etc.), step by step description of surgical procedures, management of complications, post-operative care. It includes original illustrations for better understanding and visualization of specific procedures. The book serves as a practical guide for surgical residents, surgical trainees, surgical fellows, junior surgeons, surgical consultants and anyone interested in MIS. It covers most of the basic and advanced laparoscopic and thoracoscopic surgery procedures meeting the curriculum and examination requirements of the residents

Faculty Publications and Creative Works 2002

Introduction One of the ways in which we recognize our faculty at the University of New Mexico is through Faculty Publications & Creative Works. An annual publication, it highlights our faculty\u27s scholarly and creative activities and achievements and serves as a compendium of UNM faculty efforts during the 2001 calendar year. Faculty Publications & Creative Works strives to illustrate the depth and breadth of research activities performed throughout our University\u27s laboratories, studios and classrooms. We believe that the communication of individual research is a significant method of sharing concepts and thoughts and ultimately inspiring the birth of new ideas. In support of this, UNM faculty during 2002 produced over 2,278 works, including 1,735 scholarly papers and articles, 64 books, 195 book chapters, 174 reviews, 84 creative works and 26 patented works. We are proud of the accomplishments of our faculty which are in part reflected in this book, which illustrates the diversity of intellectual pursuits in support of research and education at the University of New Mexico. Terry Yates Vice Provost for Researc