The use of primary literature can be an effective way to expose students to the scientific research process. At the same time, primary literature can be intimidating to many students, particularly ...those with limited exposure to science research. The CREATE (consider, read, elucidate hypotheses, analyze and interpret the data, and think of the next experiment) method is an evidence-based teaching strategy that uses a structured series of pedagogical tools to allow students to perform intensive analysis of primary literature. The use of CREATE in biology classes increased student self-rated attitudes, confidence, and understanding of science. On the basis of these prior reports, we implemented CREATE in a one-semester, stand-alone, undergraduate chemistry course in which students analyzed a linked series of primary literature articles tracking the trajectory of a specific area of chemistry research. The course was aimed at second-year students, and our goals were to increase student confidence in engaging scientific literature, demystify the scientific process, and help students see themselves as having a role in that process. Pre- and post-course surveys indicated significant increases in understanding of the scientific process, along with gains in self-rated skills and attitudes related to science. Students also demonstrated gains in course content knowledge as assessed by a pre- and post-course concept mapping exercise. Thus, the CREATE method has been implemented in a chemistry teaching context that resulted in increased student knowledge.
A recent push toward addressing antiracism in science reveals a need to integrate discussions of racism, social justice, and equity into undergraduate STEM classes. Toward this end, in Fall 2020, a ...theme of “Racism is a Public Health Emergency” was incorporated as an overlay for an existing undergraduate biochemistry curriculum. This theme was used throughout the entire semester and involved discussions of racism, social justice, and equity that were directly integrated with the science content of the course. Students enrolled in the class were surveyed at the end of the semester regarding their perceptions of integrating discussions of racism, social justice, and/or equity into chemistry courses. Students indicated that the inclusion of the overlay increased the relevance of the course material, indicated a high level of understanding of the impact of bias and race on the field of biochemistry, and expressed overwhelmingly positive views regarding future inclusion of similar themes of equity and antiracism in chemistry courses. Additionally, student scores and answers on common final exam questions were compared to previous semesters, revealing that the inclusion of this overlay did not negatively impact coverage of biochemistry content.
, the facultative pathogen responsible for cholera disease, continues to pose a global health burden. Its persistence can be attributed to a flexible genetic tool kit that allows for adaptation to ...different environments with distinct carbon sources, including the six-carbon sugar alcohol mannitol.
takes up mannitol through the transporter protein MtlA, whose production is downregulated at the posttranscriptional level by MtlS, a
antisense small RNA (sRNA) whose promoter lies within the
open reading frame. Though it is known that
expression is robust under growth conditions lacking mannitol, it has remained elusive as to what factors govern the steady-state levels of MtlS. Here, we show that manipulating
transcription is sufficient to drive inverse changes in MtlS levels, likely through transcriptional interference. This work has uncovered a
-acting sRNA whose expression pattern is predominantly controlled by transcription of the sRNA's target gene.
is a bacterial pathogen that relies on genetic tools, such as regulatory RNAs, to adapt to changing extracellular conditions. While many studies have focused on how these regulatory RNAs function, fewer have focused on how they are themselves modulated.
expresses the noncoding RNA MtlS, which can regulate mannitol transport and use, and here we demonstrate that MtlS levels are controlled by the level of transcription occurring in the antisense direction. Our findings provide a model of regulation describing how bacteria like
can modulate the levels of an important regulatory RNA. Our work contributes to knowledge of how bacteria deploy regulatory RNAs as an adaptive mechanism to buffer against environmental flux.
The number of people living with dementia is rising globally as life expectancy increases. Dementia is a multifactorial disease. Due to the ubiquity of radiation exposure in medical and occupational ...settings, the potential association between radiation and dementia, and its subtypes (Alzheimer's and Parkinson's disease), is of particular importance. There has also been an increased interest in studying radiation induced dementia risks in connection with the long-term manned space travel proposed by The National Aeronautics and Space Administration (NASA). Our aim was to systematically review the literature on this topic, and use meta-analysis to generate a summary measure of association, assess publication bias and explore sources of heterogeneity across studies. We identified five types of exposed populations for this review: 1. survivors of atomic bombings in Japan; 2. patients treated with radiation therapy for cancer or other diseases; 3. occupationally exposed workers; 4. those exposed to environmental radiation; and 5. patients exposed to radiation from diagnostic radiation imaging procedures. We included studies that considered incident or mortality outcomes for dementia and its subtypes. Following PRISMA guidelines, we systematically searched the published literature indexed in PubMed between 2001 and 2022. We then abstracted the relevant articles, conducted a risk-of-bias assessment, and fit random effects models using the published risk estimates. After we applied our eligibility criteria, 18 studies were identified for review and retained for meta-analysis. For dementia (all subtypes), the summary relative risk was 1.11 (95% CI: 1.04, 1.18; P = 0.001) comparing individuals receiving 100 mSv of radiation to those with no exposure. The corresponding summary relative risk for Parkinson's disease incidence and mortality was 1.12 (95% CI 1.07, 1.17; P <0.001). Our results provide evidence that exposure to ionizing radiation increases the risk of dementia. However, our findings should be interpreted with caution due to the small number of included studies. Longitudinal studies with improved exposure characterization, incident outcomes, larger sample size, and the ability to adjust for effects of potential confounders are needed to better assess the possible causal link between ionizing radiation and dementia.
Urban tree classification enables informed decision-making processes in urban planning and management. This paper introduces a novel data reformation method, pseudo tree crown (PTC), which enhances ...the feature difference in the input layer and results in the improvement of the accuracy and efficiency of urban tree classification by utilizing artificial intelligence (AI) techniques. The study involved a comparative analysis of the performance of various machine learning (ML) classifiers. The results revealed a significant enhancement in classification accuracy, with an improvement exceeding 10% observed when high spatial resolution imagery captured by an unmanned aerial vehicle (UAV) was utilized. Furthermore, the study found an impressive average classification accuracy of 93% achieved by a classifier built on the PyTorch framework, with ResNet50 leveraged as its convolutional neural network layer. These findings underscore the potential of AI-driven approaches in advancing urban tree classification methodologies for enhanced urban planning and management practices.
The ubiquity of small RNAs (sRNAs) in bacteria is now well established. These transcripts are the members of regulatory circuits involved in diverse processes ranging from stress adaptation to ...virulence to metabolism. Recent large-scale searches suggest that there exist many times more sRNAs than previously predicted even in the best studied bacterial transcriptomes. On the basis of these and other recent findings of regulatory sRNAs that do not function in a ‘classical’ manner, we propose that the working definition of sRNAs be broadened.
Objective Aneurysm growth after endovascular aneurysm repair (EVAR) in patients with type II endoleak is associated with adverse outcomes. This study evaluated the long-term success of embolization ...of type II endoleaks in preventing aneurysm sac growth. Methods We retrospectively reviewed outcomes of patients who underwent infrarenal EVAR who were treated for a type II endoleak between 2000 and 2008. Computed tomography scans were evaluated for aneurysm sac growth or shrinkage from the time of treatment of the endoleak. The embolization material used, graft type, target vessel embolized, and comorbidities were evaluated for their association with sac growth or shrinkage. Results Ninety-five patients underwent 140 embolization procedures. The mean time from EVAR to embolization was 26.1 ± 22.2 months, and the average increase in size of the aneurysm sac from EVAR to treatment was 0.7 × 0.5 cm. Patients underwent an average of 1.6 ± 0.8 embolization procedures after EVAR. Thirteen patients underwent initial simultaneous embolization of two targets. Embolization was with glue (61%), coils (29%), glue and coils (7%), and Gelfoam (3%; Pfizer Inc, New York, NY). No abdominal aortic aneurysms (AAA) ruptured. Eight patients (8.4%) underwent graft explant and open repair; 19 (20%) required two or more embolization procedures. There was no difference in the target vessel treated or the treatment used in halting sac expansion (>5 mm). Coil embolization alone resulted in more second procedures. The 5-year cumulative survival was 65% (95% confidence interval CI, 52%-77%), freedom from explant was 89% (95% CI, 81%-97%), freedom from second embolization was 76% (95% CI, 66%-86%), and freedom from sac expansion >5 mm was 44% (95% CI 30%-50%). Univariable analysis identified continued tobacco use (hazard ratio HR, 2.30; 95% CI, 1.02-5.13; P = .04) was associated with continued sac expansion, and hyperlipidemia (HR, 9.64; 95% CI, 2.22-41.86) was associated with patients requiring a second embolization procedure. Conclusions Embolization of type II endoleaks is successful early in preventing aneurysm sac growth and rupture after EVAR. However, a significant number of patients require more than one procedure, and at 5 years, many patients who underwent embolization of a type II endoleak continued to experience sac growth. Patients with hyperlipidemia who undergo coil embolization are more likely to require a second embolization procedure, and patients who smoke have a higher likelihood of AAA sac expansion after embolization. Continued long-term surveillance is necessary in this cohort of patients.
A combination of optical imaging technologies with cancer-specific molecular imaging agents is a potentially powerful strategy to improve cancer detection and enable image-guided surgery. Bladder ...cancer is primarily managed endoscopically by white light cystoscopy with suboptimal diagnostic accuracy. Emerging optical imaging technologies hold great potential for improved diagnostic accuracy but lack imaging agents for molecular specificity. Using fluorescently labeled CD47 antibody (anti-CD47) as molecular imaging agent, we demonstrated consistent identification of bladder cancer with clinical grade fluorescence imaging systems, confocal endomicroscopy, and blue light cystoscopy in fresh surgically removed human bladders. With blue light cystoscopy, the sensitivity and specificity for CD47-targeted imaging were 82.9 and 90.5%, respectively. We detected variants of bladder cancers, which are diagnostic challenges, including carcinoma in situ, residual carcinoma in tumor resection bed, recurrent carcinoma following prior intravesical immunotherapy with Bacillus Calmette-Guérin (BCG), and excluded cancer from benign but suspicious-appearing mucosa. CD47-targeted molecular imaging could improve diagnosis and resection thoroughness for bladder cancer.
Tropospheric ozone in CMIP6 simulations Griffiths, Paul T; Murray, Lee T; Zeng, Guang ...
Atmospheric chemistry and physics,
03/2021, Letnik:
21, Številka:
5
Journal Article
Recenzirano
Odprti dostop
The evolution of tropospheric ozone from 1850 to 2100 has been studied using data from Phase 6 of the Coupled Model Intercomparison Project (CMIP6). We evaluate long-term changes using coupled ...atmosphere–ocean chemistry–climate models, focusing on the CMIP Historical and ScenarioMIP ssp370 experiments, for which detailed tropospheric-ozone diagnostics were archived. The model ensemble has been evaluated against a suite of surface, sonde and satellite observations of the past several decades and found to reproduce well the salient spatial, seasonal and decadal variability and trends. The multi-model mean tropospheric-ozone burden increases from 247 ± 36 Tg in 1850 to a mean value of 356 ± 31 Tg for the period 2005–2014, an increase of 44 %. Modelled present-day values agree well with previous determinations (ACCENT: 336 ± 27 Tg; Atmospheric Chemistry and Climate Model Intercomparison Project, ACCMIP: 337 ± 23 Tg; Tropospheric Ozone Assessment Report, TOAR: 340 ± 34 Tg). In the ssp370 experiments, the ozone burden increases to 416 ± 35 Tg by 2100. The ozone budget has been examined over the same period using lumped ozone production (PO3) and loss (LO3) diagnostics. Both ozone production and chemical loss terms increase steadily over the period 1850 to 2100, with net chemical production (PO3-LO3) reaching a maximum around the year 2000. The residual term, which contains contributions from stratosphere–troposphere transport reaches a minimum around the same time before recovering in the 21st century, while dry deposition increases steadily over the period 1850–2100. Differences between the model residual terms are explained in terms of variation in tropopause height and stratospheric ozone burden.
Colonization of the infant gut by microorganisms over the first year of life is crucial for development of a balanced immune response. Early alterations in the gastrointestinal microbiota of neonates ...has been linked with subsequent development of asthma and atopy in older children. Here we describe high-resolution culture-independent analysis of stool samples from 6-month old infants fed daily supplements of Lactobacillus casei subsp. Rhamnosus (LGG) or placebo in a double-blind, randomized Trial of Infant Probiotic Supplementation (TIPS). Bacterial community composition was examined using a high-density microarray, the 16S rRNA PhyloChip, and the microbial assemblages of infants with either high or low LGG abundance were compared. Communities with high abundance of LGG exhibited promotion of phylogenetically clustered taxa including a number of other known probiotic species, and were significantly more even in their distribution of community members. Ecologically, these aspects are characteristic of communities that are more resistant to perturbation and outgrowth of pathogens. PhyloChip analysis also permitted identification of taxa negatively correlated with LGG abundance that have previously been associated with atopy, as well as those positively correlated that may prove useful alternative targets for investigation as alternative probiotic species. From these findings we hypothesize that a key mechanism for the protective effect of LGG supplementation on subsequent development of allergic disease is through promotion of a stable, even, and functionally redundant infant gastrointestinal community.
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