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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]

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]

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.

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]

Author(s): Albert C. Aragons [1, 2, 3]; Naomi L. Haworth [4]; Nadim Darwish (corresponding author) [1, 2]; Simone Ciampi (corresponding author) [5]; Nathaniel J. Bloomfield [4]; Gordon G. Wallace [5]; [...]

Bornite electrodes were characterized in the absence or in the presence of Acidithiobacillus ferrooxidans, which is an important microorganism involved in metal bioleaching processes. The presence of the bacterium modified the mineral/electrolyte interface, increasing the corrosion rate, as revealed by interferometric, AEM, ICP and EIS analyses. As a consequence of bacterial activity the electrode became porous, increasing its surface heterogeneity. This behavior was correlated with the evolution of impedance diagrams obtained during the time course of experiments. The main difference in these diagrams was the presence of an inductive feature (up to 44 h), which was related to bacterial action on the mineral dissolution, better than to its adhesion on the bornite. The total real impedance measured in presence of the bacterium was about 10 times lower than in its absence, due to the acceleration of the mineral dissolution, because an oxidant environment was maintained.

We describe a methodology to perform reliable tunneling spectroscopy in electrochemical media. Sequential in situ tunneling spectra are recorded while the electrochemical potential of the electrode is scanned. Spectroscopic data are presented as conductance maps or conductograms that show the in situ electronic structure of an electrode surface while it undergoes an electrochemical reaction. The conductance map or conductogram represents the redox fingerprint of an electrode/liquid interface in a specific medium and can serve to predict its electrochemical behavior in a quantitative energy scale. The methodology is validated studying the reversible oxidation and passivity of an iron electrode in borate buffer, and we describe the main quantitative information that can be extracted concerning the semiconducting properties of the Fe passive film. This methodology is useful to study heterogeneous catalysis, electrochemical sensing and bioelectronic systems.

We present a new procedure to prepare Pt/Ir probes for electrochemical scanning tunneling microscopy (STM) and spectroscopy applications. We detail the experimental setup and the improvements over previous methods. The probes have been used successfully for measurements of tunneling spectroscopy under electrochemical control, which requires scanning the potential of the tip at high velocity.

A complex of CstF-64 and the SL2 snRNP has been found to connect mRNA 3' end formation and trans-splicing in Caenorhabditis elegans operons. CstF-64 is the homolog to the RNA-binding subunit of mammalian CstF. Immunoprecipitations were carried out using an antibody to C. elegans CstF-64. SL2 RNA is precipitated with alpha CstF-64 while other snRNAs were not.

The RNA binding characteristics of wild-type and deletion constructs of polypyrimidine tract binding protein that have RNA recognition motifs in both an oligomeric and monomeric context were examined to correlate structural motifs with their roles. Results showed that there is no strong correlation between the RNA binding affinity and specificity upon oligomerization. However, the mode of RNA interaction and dimerization is related.

Background: Animal models have been important for the understanding of Alzheimer's disease and related dementias (ADRD). However, most of the research involving these diseases has been with rodents. Researchers have raised awareness about the need for alternative and feasible animal models in order to understand these types of diseases. To increase the knowledge of alternative animal models for the study of ADRD, the current study proposed the use of the Monodelphis domestica animal model to detect the presence of amyloid beta and tau proteins. Method: Fixed brains from young adult Monodelphis were used in the present study. A standard immunohistochemistry (ABC‐DAB) staining protocol was used to detect amyloid beta and tau proteins. To detect the presence of amyloid beta, a 1:100 anti‐amyloid primary dilution was used; for tau protein, a 1:1000 anti‐tau primary dilution was utilized. Only the hippocampal region was selected for description and quantification. An Axioscan Z.1 microscope system was utilized to capture images, and image analysis was performed using ImageJ software. Result: The area of the hippocampus of the first coronal section was 30262602.934 um2. The results from an amyloid‐beta dilution of 1:100 detected amyloid beta in a number of neurons in the hippocampus. Amyloid beta was also detected in the hippocampus of another brain section (total area: 7048008 um2). The negative control tissue did not reveal positive signal in neurons in the hippocampal area, suggesting low levels of non‐specific binding. The results for tau antibody are pending. Conclusion: Our study revealed that in Monodelphis domestica animal model brain tissue, a 1:100 dilution resulted in identification of positive amyloid beta protein. However, no abnormal amyloid beta plaque formation was found with this animal model. A possible explanation was that a natural, non‐induced animal model was used in the study. [ABSTRACT FROM AUTHOR]

The scanning tunneling microscope break junction technique is employed to explain the various transport characteristics that are exhibited by the long conjugated molecular wires. The impact of the length and the temperature on the conductance behavior of these wires is also analyzed.

The oxidation and reduction processes of both polycrystalline tin and Sn (100) single crystals are investigated in borate buffer solution of pH 7.5 using cyclic voltammetry and in-situ characterizations such as Raman scattering, potential modulated reflectance spectroscopy (PMRS), and electrochemical scanning tunneling microscopy (EC-STM).

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]