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A Zugunruhe Data Collection System Using Passive Infrared Sensors
Get PDFWhen engineers and biologists work together, there is a lot to learn on both sides. For instance, our work introduced us to zugunruhe, which is a German word that means “unrest”. It is used in the context of migratory birds, as they become restless at night, inside their cages, during their migratory period. When does zugunruhe start? It usually starts when the weather becomes cold and the days shorter, but it varies for different bird species. Moreover, global warming has caused changes in zungunruhe’s timing, which made it even harder to predict. Another question is about genetics: is there a specific gene or a group of genes that cause birds to migrate? To help scientists answer questions related to zugunruhe and the genes underlying migratory behavior, this paper presents the design and implementation of a zugunruhe data collection system to study the Swainson’s thrush, a migratory songbird that breeds in North America. Our goal is to share how custom-off-the-shelf (COTS) devices and existing technologies were used in this project, such as passive infrared motion sensors, telecom cables, custom printed circuit boards (PCB) and a data acquisition system using LabView software. All these were combined to monitor bird movements. We also discuss how the learned lessons from our first winter of data collection, in which we monitored 30 bird cages, led to improvements to scale the system to support the monitoring of 60 birds in the second year. Samples of the collected data are presented to show that the system works, which was validated by comparing our data with the images obtained using an infrared camera. Some of the challenges on maintaining the system are also discussed. Moreover, this paper provides an example of an interdisciplinary, applied research project that is still on-going, and it was created by a group of undergraduate students. We hope it can inspire other researchers and undergraduate students to get involved in interdisciplinary research
World Food Day - Program
No full textHosted by the College of Agriculture and Human Sciences (CAHS), the event featured representatives from the United States Department of Agriculture, United Nations Food and Agriculture Organization (FAO), the City of Prairie View, and Texas A&M University. Presenters discussed what systemic and individual steps are needed to combat global food insecurity.
World Food Day is an international holiday to commemorate the establishment of the FAO, the United Nation’s oldest technical organization. Each Oct. 16, outreach activities across the globe raise awareness for food-insecure countries, states, cities, and towns and encourage others to do their part to curb the increasing levels of nutrition disparity. This year’s observance explored the theme, “Our Actions are Our Future.
Interactions of Cellulose Model Compound D-Cellobiose with Selected Metal Chlorides in Water: Identification of Chelating Oxygen Atoms
No full textUnderstanding interactions of metal ions with cellulose is an important step in the development of efficient catalytic methods for processing cellulose. In this study, density functional theory methods were used to identify oxygen atoms interacting or chelating with selected metal chlorides of Li+, K+, Mg2+, Ca2+, Sn2+, Zn2+ and La3+ with cellulose model compound D-cellobiose. Calculated metal-oxygen distances of energy minimized D-cellobiose : metal chloride 1 : 2 mixtures revealed that the metal ions approach between the two glucose rings in α/β-D-cellobiose, and O4, O9 are the preferred interaction/chelation points. DFT study supported a previous 13C NMR chemical shift change based experiments. ZnCl2 showing the shortest metal-oxygen distances in approach to α/β D-cellobiose is known to produce the largest 13C NMR chemical shift changes in D-cellobiose. In α-anomer, average closest metal-oxygen distances and NMR shift changes co-related at 95 % confidence interval with liner regression R2=0.8582 and Sy.x=0.5722
Climate change impact and variability on cereal productivity among smallholder farmers under future production systems in west africa
No full textAgriculture in West Africa is constrained by several yield-limiting factors, such as poor soil fertility, erratic rainfall distributions and low input systems. Projected changes in climate, thus, pose a threat since crop production is mainly rain-fed. The impact of climate change and its variation on the productivity of cereals in smallholder settings under future production systems in Navrongo, Ghana and Nioro du Rip, Senegal was assessed in this study. Data on management practices obtained from household surveys and projected agricultural development pathways (through stakeholder engagements), soil data, weather data (historical: 1980–2009 and five General Circulation Models; mid-century time slice 2040–2069 for two Representative Concentration Pathways; 4.5 and 8.5) were used for the impact assessment, employing a crop simulation model. Ensemble maize yield changes under the sustainable agricultural development pathway (SDP) were −13 and −16%, while under the unsustainable development pathway (USDP), yield changes were −19 and −20% in Navrongo and Nioro du Rip, respectively. The impact on sorghum and millet were lower than that on maize. Variations in climate change impact among smallholders were high with relative standard deviations (RSD) of between 14% and 60% across the cereals with variability being higher under the USDP, except for millet. Agricultural production systems with higher intensification but with less emphasis on soil conservation (USDP) will be more negatively impacted by climate change compared to relatively sustainable ones (SDP)
PROTOCOL: Effectiveness of parent-engagement programs to reduce truancy and juvenile delinquency: A systematic review
No full textThis review aims to synthesize the evaluation evidence for parent-engagement programs that focus on reducing juvenile truancy as the primary outcome. Delinquent behavior will be assessed as a secondary outcome when included. This objective is guided by the following research questions: (1) what is the effectiveness of parent-engagement programs for children in preschool (ages 4–5) through secondary education (ages 13–19) on primarily (a) reducing student truancy (i.e., unexcused or unauthorized absence) and secondarily (and when included) (b) reducing delinquent behaviors? (2) Is there variability in the effectiveness of parent-engagement programs across moderators such as gender, age, grade levels, settings, and contexts? (3) What factors (e.g., groups, settings, and contexts) explain the variability in the effectiveness of engagement programs in a multivariate framework?
Electrospun biodegradable bi-layered microfiber membranes for aluminum removal from drinking water
No full textAims: This study aimed to eliminate metallic contaminants from drinking water by using electrospun bi-layered microfiber membranes. Background: Fast industrialization triggers environmental pollution. Heavy metals like silver, lead and aluminum are the major contaminants that are extremely toxic and accumulate in biological tissues through the food chain and cause a health hazard. Electrospinning is a promising technique among other conventional techniques of removing these metals from drinking water. Electrospun membranes possess suitable properties for microfiltration purposes. In this study, to fabricate electrospun membranes, polycaprolactone (PCL) and zeolites were used as materials. PCL polymer is biocompatible and biodegradable, and zeolite is microporous, which is good for filtration or molecular sieving application. Method: Using the electrospinning technique, PCL, PCL/zeolite, PCL and PCL/zeolite bi-layered electrospun membranes were fabricated. The properties of the membranes were evaluated using different techniques. The performance of the membranes was tested by filtering Aluminum (Al) present in drinking water. Results: Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analyses confirmed the removal of Al using the membranes. ICP-OES results showed more than 90% of Al removal using PCL and PCL/zeolite electrospun membranes. Conclusion: These membranes are non-toxic and biodegradable and have the potential to be used for microfiltration purposes
(R1504) Second-order Modified Nonstandard Runge-Kutta and Theta Methods for One-dimensional Autonomous Differential Equations
Get PDFNonstandard finite difference methods (NSFD) are used in physical sciences to approximate solutions of ordinary differential equations whose analytical solution cannot be computed. Traditional NSFD methods are elementary stable but usually only have first order accuracy. In this paper, we introduce two new classes of numerical methods that are of second order accuracy and elementary stable. The methods are modified versions of the nonstandard two-stage explicit Runge-Kutta methods and the nonstandard one-stage theta methods with a specific form of the nonstandard denominator function. Theoretical analysis of the stability and accuracy of both modified NSFD methods is presented. Numerical simulations that concur with the theoretical findings are also presented, which demonstrate the computational advantages of the proposed new modified nonstandard finite difference methods
(R1505) A Note on Large Deviations in Insurance Risk
Get PDFWe study large and moderate deviations for an insurance portfolio, with the number of claims tending to infinity, without assuming identically distributed claims. The crucial assumption is that the centered claims are bounded, and that variances are bounded below. From a general large deviations upper bound, we obtain an exponential bound for the probability of the average loss exceeding a threshold. A counterexample shows that a full large deviation principle, including also a lower bound, does not follow from our assumptions. We argue that our assumptions make sense, in particular, for life insurance portfolios and discuss how to apply our upper bound in this context. Finally, we use a moderate deviations result by Petrov (1954) to estimate the probability of exceeding a threshold that depends on portfolio size. In this asymptotic regime, the rate function that determines the asymptotic behavior is explicit and thus very easy to compute numerically, without solving an optimization problem