Learning and Memory in a Drosophila melanogaster Model of Alzheimer\u27s Disease

Human Alzheimer\u27s disease (AD) is the most prevalent and lethal neurodegenerative disease; it involves the accumulation of neurofibrillary tangles, loss of synapses and neurons in specific areas of the brain, and the presence of extracellular amyloid plaques, particularly Amyloid beta-42 (AP-42). In this study, two Drosophila transgenic fly lines carrying either elav-GAL4 driver or UAS-AP-42 transgene, were crossed to generate AD flies that expressed low levels of human Ap-42. Male AD flies (experimental) and elav-GAL4 flies (as parental control without AP-42) were tested for learning and short-term memory using the courtship suppression assay (Siegal and Hall, 1979). The courtship suppression assay includes training and testing periods, where male flies rejected by a previously mated female during training will retain the memory and therefore exhibit less courtship behaviors in testing period. First, a single virgin male was assigned to one of three training conditions: paired with a previously mated (trainer) female (experimental condition), a virgin female, or no female (sham control). After one hour of training, all males were transferred and paired with virgin females for ten minutes. Independent raters reviewed the training and testing videos and calculated courtship indices (CI) reflecting the amount of time males engaged in characteristic courtship behaviors (ex. orientation, wing vibration, tapping). Both 4-6 days-old elav-GAL4 and AD males exhibited less courtship behaviors towards mated females, suggesting the efficacy of training. In addition, trained elav-GAL4 males had a lower average CI than the sham control in testing, indicating their short term memory is intact. However, the average testing CI for 4-6 days-old trained AD males was similar compared to their sham control group. Our results showed that four-to-five days-old AD males already exhibited deficits in short-term memory

Chronoprints: Identifying Samples by Visualizing How They Change over Space and Time.

The modern tools of chemistry excel at identifying a sample, but the cost, size, complexity, and power consumption of these instruments often preclude their use in resource-limited settings. In this work, we demonstrate a simple and low-cost method for identifying a sample based on visualizing how the sample changes over space and time in response to a perturbation. Different types of perturbations could be used, and in this proof-of-concept we use a dynamic temperature gradient that rapidly cools different parts of the sample at different rates. We accomplish this by first loading several samples into long parallel channels on a "microfluidic thermometer chip." We then immerse one end of the chip in liquid nitrogen to create a dynamic temperature gradient along the channels, and we use an inexpensive USB microscope to record a video of how the samples respond to the changing temperature gradient. The video is then converted into several bitmap images (one per sample) that capture each sample's response to the perturbation in both space (the y-axis; the distance along the dynamic temperature gradient) and time (the x-axis); we call these images "chronological fingerprints" or "chronoprints" of each sample. If two samples' chronoprints are similar, this suggests that the samples are the same chemical substance or mixture, but if two samples' chronoprints are significantly different, this proves that the samples are chemically different. Since chronoprints are just bitmap images, they can be compared using a variety of techniques from computer science, and in this work we use three different image comparison algorithms to quantify chronoprint similarity. As a demonstration of the versatility of chronoprints, we use them in three different applications: distinguishing authentic olive oil from adulterated oil (an example of the over $10 billion global problem of food fraud), identifying adulterated or counterfeit medication (which represents around 10% of all medication in low- and middle-income countries), and distinguishing the occasionally confused pharmaceutical ingredients glycerol and diethylene glycol (whose accidental or intentional substitution has led to hundreds of deaths). The simplicity and versatility of chronoprints should make them valuable analytical tools in a variety of different fields

Sudden death in patients without structural heart disease

AbstractSudden unexpected cardiac death generally occurs in persons with known or previously unrecognized heart disease. However, it has become evident that it occurs often enough in patients without any identifiable structural abnormality to warrant the cardiologist's attention. Mostly, it concerns young, active, and otherwise healthy individuals. This paper focuses on various categories of patients with life-threatening events considered to have occurred on a solely “electrical” basis. Currently, several entities are recognized with distinct electrophysiological abnormalities, including Wolff-Parkinson-White syndrome, long QT syndrome, the Brugada syndrome, short-coupled torsade de pointes, and catecholamine-induced polymorphic ventricular tachyarrhythmia. The remaining patients without such distinct abnormalities are categorized as having idiopathic ventricular fibrillation. Although mechanical cardiac function may seem normal, such patients might have certain discrete anatomic abnormalities, unidentifiable with current investigational tools. Possibly in the future, with development of newer and more sophisticated tools (magnetic resonance imaging, positron emission tomography, genetic testing), some or all cases of idiopathic ventricular fibrillation must be redefined as having specific genetic and/or anatomic bases. All patients successfully resuscitated from cardiac arrest due to ventricular tachyarrhythmia without clear precipitating factors (acute myocardial infarction, severe electrolyte or metabolic disturbances) are at high risk of recurrences. Long-term prophylactic therapy is indicated. Contrasting with older belief, survivors of idiopathic ventricular fibrillation are now also considered high-risk patients. The implantable cardioverter-defibrillator appears to be the safest and most effective therapy

Virtual Simulation of Robotic Operations Using Gaming Software

The main objective of the project is to provide a Virtual Reality (VR) representation for robotic simulations using a game engine software such as Unity. It is useful to an ongoing research on testing the compatibility of training collaborative robots entirely in VR to further enhance the use of human-robot collaboration in industry. The success of the research project implies that collaborative robots can be tested and trained via software running numerous simulations more efficiently than the traditional operation of robotic designs in industry. The UR10e robot arm is the industrial robot to be tested in VR. To provide the simulation for the research, four objectives are set across a timeline. A CAD model of the UR10e will be imported into Unity without any loss of data. Next, the UR10e’s degrees of freedom (DOF) will be added into the game engine such that its movements have the same constraints as its actual design. Then, a 3D environment is added onto the game engine simulation such that the game engine robot can interact with a virtual workspace. Finally, the game engine robot is assigned to perform a simple task such as a pick and place activity. The robot must be able to perform the task autonomously and a user interface (UI) must also be added such that an operator can manually direct the robot’s movements for the task given

Identifying Nontraditional Epidemic Disease Risk Factors Associated with Major Health Events from World Health Organization and World Bank Open Data

Health events emerge from host, community, environment, and pathogen factors-forecasting epidemics is a complex task. We describe an exploratory analysis to identify economic risk factors that could aid epidemic risk assessment. A line list was constructed using the World Health Organization Disease Outbreaks News (2016-2018) and economic indicators from the World Bank. Poisson regression employing forward imputations was used to establish relationships with the frequency with which countries reported public health events. Economic indicators demonstrated strong performance appropriate for further assessment in surveillance programming. In our analysis, three economic indicators were significantly associated to event reporting: how much the country\u27s urban population changed, its average forest area, and a novel economic indicator we developed that assessed how much the gross domestic product changed per capita. Other economic indicators performed less well: changes in total, female, urban, and rural population sizes; population density; net migration; change in per cent forest area; total forest area; and another novel indicator, change in percent of trade as a fraction of the total economy. We then undertook a further analysis of the start of the current COVID-19 pandemic that revealed similar associations, but confounding by global disease burden is likely. Continued development of forecasting approaches capturing information relevant to whole-of-society factors (e.g., economic factors as assessed in our study) could improve the risk management process through earlier hazard identification and inform strategic decision processes in multisectoral strategies to preventing, detecting, and responding to pandemic-threat events

Identifying Nontraditional Epidemic Disease Risk Factors Associated with Major Health Events from World Health Organization and World Bank Open Data

Health events emerge from host, community, environment, and pathogen factors-forecasting epidemics is a complex task. We describe an exploratory analysis to identify economic risk factors that could aid epidemic risk assessment. A line list was constructed using the World Health Organization Disease Outbreaks News (2016-2018) and economic indicators from the World Bank. Poisson regression employing forward imputations was used to establish relationships with the frequency with which countries reported public health events. Economic indicators demonstrated strong performance appropriate for further assessment in surveillance programming. In our analysis, three economic indicators were significantly associated to event reporting: how much the country\u27s urban population changed, its average forest area, and a novel economic indicator we developed that assessed how much the gross domestic product changed per capita. Other economic indicators performed less well: changes in total, female, urban, and rural population sizes; population density; net migration; change in per cent forest area; total forest area; and another novel indicator, change in percent of trade as a fraction of the total economy. We then undertook a further analysis of the start of the current COVID-19 pandemic that revealed similar associations, but confounding by global disease burden is likely. Continued development of forecasting approaches capturing information relevant to whole-of-society factors (e.g., economic factors as assessed in our study) could improve the risk management process through earlier hazard identification and inform strategic decision processes in multisectoral strategies to preventing, detecting, and responding to pandemic-threat events

Study on the effect of contrast agent on biofilms and their visualization in porous substrate using x-ray μCT

Investigation of biofilms and visualization using non-destructive imaging techniques like X-ray μCT has recently gained interest. Biofilms are congregations of microorganisms that attach to surfaces and comprise of microbial cells embedded in extracellular polymeric substances (EPS). They are ubiquitous entities that are commonly found in any non-sterile setting and have direct implications on human health. Methods to visualize them in-situ are highly needed to understand their behaviour (attachment and detachment) inside a substrate. Contrast-enhanced X-ray μCT is a 3D imaging technique that is capable of visualising objects that have very low attenuation contrast. The use of contrast agents in X-ray μCT has been an evolving process, however, the possible toxic effect of these chemical compounds against biofilms has not been studied in detail. In this study, we focus on the toxic effect of contrast agents and study the diffusion and drainage of contrast agents in biofilms. We propose using water-soluble potassium bromide (KBr) as a suitable contrast agent for enhancement of the attenuation coefficient of a monoculture of Pseudomonas fluorescens biofilms inside a porous substrate. At the given concentration, KBr proved to be less bactericidal compared to other commonly used contrast agents and at 5% w/v concentration we were able to clearly distinguish between the biofilm and the porous substrate

Perfil, hábitos e atitudes do consumidor do presunto de Chaves

Esta comunicação tem por objectivos traçar o perfil do consumidor do Presunto de Chaves; conhecer os seus hábitos, as suas preferências e as suas atitudes; determinar o grau de influência de características, designadamente, pessoais, sociais, geográficas, económicas e contextuais, na decisão de compra deste produto e verificar a existência de diferenças de atitudes e comportamentos entre grupos no que diz respeito ao consumo deste tipo de produto. Esta investigação apoia-se em dados primários obtidos através da aplicação de um questionário a 200 turistas e ou visitantes do concelho de Chaves no período de Julho a Outubro do ano de 2006

Loss of Courtship Suppression Memory in a Drosophila melanogaster Model of Alzheimer’s Disease

Alzheimer’s disease (AD) is the most prevalent and lethal neurodegenerative disease. Memory loss and motor dysfunction are accompanied by pathological hallmarks like neurofibrillary tangles or amyloid plaques. In this study, courtship suppression assay was used to assess learning and memory of a transgenic Drosophila melanogaster (the fruit fly) line expressing human Amyloid beta 42 (Aβ42). At young age (4–6 days old), both parental control and AD flies displayed lower courtship indices during training after being rejected by previously mated females. However, in the subsequent testing phase, young AD flies showed compromised recall memory, unlike that of parental controls. Neither control nor AD flies at 16–18 days old showed significant learning or recall memory. AD flies also exhibited age-related motor defects and presented amyloid plaques in brain sections. Interestingly, older AD flies displayed persistent chasing throughout the one-hour training period, and they attempted copulation at higher frequency than the untrained AD controls. Thus, transgenic AD flies displayed early onset of memory deficit, and aggressive courtship behavior as they aged. This article was published Open Access through the CCU Libraries Open Access Publishing Fund. The article was first published in eBio: https://www.eaglehill.us/ebio-pdfs-regular/EBIO-009-Lin.pd