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Undergraduate research experiences provide excellent examples of high-impact practices. They rely on inquiry-based learning to provide important capstone experiences for the students. However, they are time-intensive for mentor faculty. In an attempt to scale up our faculty’s ability to offer such experiences, we combined a number of projects into one class: the Biomathematics Workshop. This article chronicles the experiences of one student from that class interspersed with comments from his mentor. Our goal is to illustrate some of the twists and turns in his journey and the unexpected but valuable lessons the student (and the mentoring team) learned. [ABSTRACT FROM AUTHOR]

In recent years, various single-molecule electronic components have been demonstrated. However, it remains difficult to predict accurately the conductance of a single molecule and to control the lateral coupling between the π orbitals of the molecule and the orbitals of the electrodes attached to it. This lateral coupling is well known to cause broadening and shifting of the energy levels of the molecule; this, in turn, is expected to greatly modify the conductance of an electrode-molecule-electrode junction. Here, we demonstrate a new method, based on lateral coupling, to mechanically and reversibly control the conductance of a single-molecule junction by mechanically modulating the angle between a single pentaphenylene molecule bridged between two metal electrodes. Changing the angle of the molecule from a highly tilted state to an orientation nearly perpendicular to the electrodes changes the conductance by an order of magnitude, which is in qualitative agreement with theoretical models of molecular π-orbital coupling to a metal electrode. The lateral coupling is also directly measured by applying a fast mechanical perturbation in the horizontal plane, thus ruling out changes in the contact geometry or molecular conformation as the source for the conductance change. [ABSTRACT FROM AUTHOR]

The charge transport characteristics of a family of long conjugated molecular wires have been studied using the scanning tunneling microscope break junction technique. The family consists of four wires ranging from 3.1 to 9.4 nm in length. The two shortest wires show highly length dependent and temperature invariant conductance behavior, whereas the longer two wires show weakly length dependent and temperature variant behavior. This trend is consistent with a model whereby conduction occurs by two different mechanisms in the family of wires: by a coherent tunneling mechanism in the shorter two and by an incoherent charge hopping process in the longer wires. The temperature dependence of the two conduction mechanisms gives rise to a phenomenon whereby at elevated temperatures longer molecules that conduct via charge hopping can yield a higher conductance than shorter wires that conduct via tunneling. The evolution of molecular junctions as the tip retracts has been studied and explained in context of the characteristics of individual transient current decay curves. [ABSTRACT FROM AUTHOR]

Hypoxia (low-oxygen) is one of the most common characteristics of solid tumours. Exploiting tumour hypoxia to reductively activate Pt(IV) prodrugs has the potential to deliver toxic Pt(II) selectively and thus overcome the systemic toxicity issues of traditional Pt(II) therapies. However, our current understanding of the behaviour of Pt(IV) prodrugs in hypoxia is limited. Here, we evaluated and compared the aryl carbamate fluorogenic Pt(IV) complexes, CisNap and CarboNap, as well as the previously reported OxaliNap, as potential hypoxia-activated Pt(IV) (HAPt) prodrugs. Low intracellular oxygen concentrations (<0.1%) induced the greatest changes in the respective fluorescence emission channels. However, no correlation between reduction under hypoxic conditions and toxicity was observed, except in the case for CarboNap, which displayed significant hypoxia-dependent toxicity. Other aryl carbamate Pt(IV) derivatives (including non-fluorescent analogues) mirrored these observations, where carboplatin(IV) derivative CarboPhen displayed a hypoxia-selective cytotoxicity similar to that of CarboNap. These findings underscore the need to perform extensive structure activity relationship studies on the cytotoxicity of Pt(IV) complexes under normoxic and hypoxic conditions. [ABSTRACT FROM AUTHOR]

Studies the contribution of multiple RNA recognition motif (RRM) to RNA binding specificity and affinity for polypyrimidine tract binding protein (PTB). Presence of four RRMs in PTB; Consistency of the PTB data with the presence of a four reiterated domain structure; Analysis of the RNA binding properties of wild-type and deletion constructs of PTB.

We report the synthesis of 4-nitrophenyl (4-NP) functionalised Pt(IV) complexes as a colorimetric strategy for monitoring Pt(IV) reduction in aqueous solution. Treatment of each 4-NP functionalised Pt(IV) complex with the biological reductant sodium ascorbate led to a colour change from clear to yellow, which was attributed to the reduction of Pt(IV) to Pt(II) and simultaneous release of 4-nitroaniline. Trends in reduction profiles and a photocatalysed reduction for each Pt(IV) complex were observed. [ABSTRACT FROM AUTHOR]

As the number of Spanish-speaking patients with cancer in the USA grows, it is vital that reliable online breast cancer information is available in Spanish. The main objective of our study was to determine the quality and reliability of online videos in Spanish regarding breast cancer. We conducted a YouTube search using the phrase "cancer de mama" (breast cancer) and graded their quality and reliability using the Journal of the American Medical Association (JAMA) Benchmark Criteria, Global Quality Score (GQS), and the Modified DISCERN Questionnaire. Videos were characterized by descriptive variables. Videos were primarily from Spain (36.4%) and Mexico (17.9%). 'professional' videos had the highest JAMA mean rank (99.53), the highest GQS mean rank (102.86) and the and second-highest DISCERN (101.10) mean rank. 'Personal' videos, by contrast, had the lowest mean rank values for GQS (72.28) and DISCERN (68.83) scores. A significant majority of online breast cancer videos in Spanish were of poor quality and reliability. 'Professional' videos are of higher quality and reliability than videos of other typologies; however, they have a limited range of content. In addition, a small percentage of videos were uploaded from the USA. [ABSTRACT FROM AUTHOR]

Research has shown that climate change creates warmer temperatures and drier conditions, leading to longer wildfire seasons and increased wildfire risks in the United States. These factors have, in turn, led to increases in the frequency, extent, and severity of wildfires in recent years. Given the danger posed by wildland fires to people, property, wildlife, and the environment, there is an urgent need to provide tools for effective wildfire management. Early detection of wildfires is essential to minimizing potentially catastrophic destruction. To that end, in this paper, we present our work on integrating multiple data sources into SmokeyNet, a deep learning model using spatiotemporal information to detect smoke from wildland fires. We present Multimodal SmokeyNet and SmokeyNet Ensemble for multimodal wildland fire smoke detection using satellite-based fire detections, weather sensor measurements, and optical camera images. An analysis is provided to compare these multimodal approaches to the baseline SmokeyNet in terms of accuracy metrics, as well as time-to-detect, which is important for the early detection of wildfires. Our results show that incorporating weather data in SmokeyNet improves performance numerically in terms of both F1 and time-to-detect over the baseline with a single data source. With a time-to-detect of only a few minutes, SmokeyNet can be used for automated early notification of wildfires, providing a useful tool in the fight against destructive wildfires. [ABSTRACT FROM AUTHOR]

The size and frequency of wildland fires in the western United States have dramatically increased in recent years. On high-fire-risk days, a small fire ignition can rapidly grow and become out of control. Early detection of fire ignitions from initial smoke can assist the response to such fires before they become difficult to manage. Past deep learning approaches for wildfire smoke detection have suffered from small or unreliable datasets that make it difficult to extrapolate performance to real-world scenarios. In this work, we present the Fire Ignition Library (FIgLib), a publicly available dataset of nearly 25,000 labeled wildfire smoke images as seen from fixed-view cameras deployed in Southern California. We also introduce SmokeyNet, a novel deep learning architecture using spatiotemporal information from camera imagery for real-time wildfire smoke detection. When trained on the FIgLib dataset, SmokeyNet outperforms comparable baselines and rivals human performance. We hope that the availability of the FIgLib dataset and the SmokeyNet architecture will inspire further research into deep learning methods for wildfire smoke detection, leading to automated notification systems that reduce the time to wildfire response. [ABSTRACT FROM AUTHOR]

The article offers information on Masticophis flagellum is a known predator of multiple lizard species from Alpine, Texas.