Background: Our study aimed to assess the radiation sensitivity of BT20, a human breast tumor cell line, using the laser-trapping technique and compare it with N2a and 4T1 cells. Additionally, we investigated the impact of the antitumor compound 2-Dodecyl-6-methoxycyclohexa-2,5-diene-1,4-dione (DMDD) on radiation sensitivity. Methods and Materials: We employed laser trapping to calculate both the threshold ionization energy (TIE) and threshold radiation dose (TRD) for BT20, N2a, and 4T1 cells. We assessed the effect of DMDD on BT20 cells’ radiosensitivity and conducted comparisons across these cell lines. Results: Our findings reveal that DMDD significantly enhances the radiosensitivity of BT20 breast carcinoma cells. Moreover, we observed distinct trends in TIE and TRD across the three cell lines, with differences attributed to variations in cell size and composition. When multiple cell ionizations were considered, a notable reduction in TRD was observed, implicating factors such as the chain effect of ionizing radiation and the influence of DMDD. The study found that TIE increased with the number of cells in the trap while TRD consistently decreased across all three cell lines, suggesting comparable radiation sensitivity, and oligostilbene treatment further reduced TRD, presenting the potential for enhancing therapeutic ratios in cancer treatment. Conclusion: The antitumor compound DMDD enhances the radiosensitivity of BT20 breast carcinoma cells, highlighting its potential in cancer treatment. Furthermore, our study underscores the impact of cell size and multiple-cell ionizations on TRD. Leveraging laser trapping techniques, biocompatible nanoparticles, and advanced optical tweezers opens promising avenues for personalized and effective cancer therapy approaches.

Our current grading system assumes everyone starts at approximately the same place. This assumption presumes uniformity and impartiality to be inherent in our school system. We argue that this is not the case. This work explores the evolution of grading systems and the integration of new technologies in education, focusing on the development of more inclusive, dynamic, and adaptable teaching and assessment strategies. Key methods include diversified assessments, experiential learning approaches such as problem-based learning and the generated question learning model, and the incorporation of artificial intelligence (AI) in hyperflex learning strategies. The proposed work astutely identifies the critical flaws within the modern grading system and puts forth a compelling solution: shifting the focus towards assessing students’ improvement scores. This approach not only offers a progressive path forward, but also significantly enhances equity by holding students accountable for their knowledge gaps while promoting a more comprehensive evaluation. Additionally, creative engagement techniques, such as mock banking reward systems, are employed to enhance student motivation and participation. AI-facilitated formative assessments and personalized learning plans are also discussed, emphasizing the importance of real-time insights into student progress and the provision of flexible personalized learning environments. This comprehensive approach to education fosters student ownership of learning, promotes active participation, and equips students with essential lifelong learning skills. Moreover, a more accurate assessment of student learning and progress would be fostered, thus creating a paradigm shift from the currently flawed grading system.

Violacein is a water-insoluble violet pigment produced by various Gram-negative bacteria. The compound and the bacteria that produce it have been gaining attention due to the antimicrobial and proposed antitumour properties of violacein and the possibility that strains producing it may have broad industrial uses. Bacteria that produce violacein have been isolated from diverse environments including fresh and ocean waters, glaciers, tropical soils, trees, fish and the skin of amphibians. We report here the isolation and characterization of six violacein-producing bacterial strains and three non-violacein-producing close relatives, each isolated from either an aquatic environment or moist food materials in northern California, USA. For each isolate, we characterized traditional phenotypes, generated and analysed draft genome sequences, and carried out multiple types of taxonomic, phylogenetic and phylogenomic analyses. Based on these analyses we assign putative identifications to the nine isolates, which include representatives of the genera Chromobacterium, Aquitalea, Iodobacter, Duganella, Massilia and Janthinobacterium. In addition, we discuss the utility of various metrics for taxonomic assignment in these groups including average nucleotide identity, whole genome phylogenetic analysis and extent of recent homologous recombination using the software program PopCOGenT.

Abstract The aim of our study was to use laser trapping technique to evaluate the radiation sensitivity of cancer cells, both untreated and chemo-treated. We focused on a specific human breast tumor cell line, called BT20, that was treated with an antitumor compound known as 2-Dodecyl-6-methoxycyclohexa-2, 5-diene-1, 4-dione. We investigated an untreated control group, as well as two groups of BT20 cells that were subjected to different treatment durations. We utilized a high-power infrared laser (at 1064 nm) trap to determine the absorbed threshold ionization energy (TIE) and threshold radiation dose (TRD) for single and multiple cells trapping and ionization. We performed statistical analyses, including descriptive and one-way ANOVA, on the results. We also analyzed the relationship between TIE and TRD to the mass of the individual cells for different hours of treatment, in comparison to the control group. Our findings revealed that both TIE and TRD decreased as treatment duration increased. However, the TRD decreased with mass irrespective of the treatment. Moreover, our analyses consistently showed the same behavior of TRD for single vs. multiple cell ionizations within each group, regardless of treatment. In addition, we conducted a comparative analysis on the effects of radiation dosage in BT20, 4T1 breast cancer, and N2a neuroblastoma cell lines, and discovered that the TRD decreased in mass across all three cell lines.

The current diagnosis of diffuse glioma involves isocitrate dehydrogenase (IDH) mutation testing. Most IDH mutant gliomas carry a G-to-A mutation at IDH1 position 395, resulting in the R132H mutant. R132H immunohistochemistry (IHC), therefore, is used to screen for the IDH1 mutation. In this study, the performance of MRQ-67, a recently generated IDH1 R132H antibody, was characterized in comparison with H09, a frequently used clone. Selective binding was demonstrated by an enzyme-linked immunosorbent assay for MRQ-67 to the R132H mutant, with an affinity higher than that for H09. By Western and dot immunoassays, MRQ-67 was found to bind specifically to the IDH1 R1322H, with a higher capacity than H09. IHC testing with MRQ-67 demonstrated a positive signal in most diffuse astrocytomas (16/22), oligodendrogliomas (9/15), and secondary glioblastomas tested (3/3), but not in primary glioblastomas (0/24). While both clones demonstrated a positive signal with similar patterns and equivalent intensities, H09 exhibited a background stain more frequently. DNA sequencing on 18 samples showed the R132H mutation in all IHC positive cases (5/5), but not in negative cases (0/13). These results demonstrate that MRQ-67 is a high-affinity antibody suitable for specific detection of the IDH1 R132H mutant by IHC and with less background as compared with H09.

In this note, we exhibit a weakly holomorphic modular form for use in constructing a Fourier eigenfunction in four dimensions. Such auxiliary functions may be of use to the D4 checkerboard lattice and the four dimensional sphere packing problem.

Photoionization of Cl III ions into Cl IV was studied theoretically using the ab initio relativistic Breit–Pauli R-matrix (BPRM) method and experimentally at the Advanced Light Source (ALS) synchrotron at the Lawrence Berkeley National Laboratory. A relative-ion-yield spectrum of Cl IV was measured with a photon energy resolution of 10 meV. The theoretical study was carried out using a large wave-function expansion of 45 levels of configurations 3s23p2, 3s3p3, 3s23p3d, 3s23p4s, 3s3p23d, and 3p4. The resulting spectra are complex. We have compared the observed spectrum with photoionization cross sections (σPI) of the ground state 3s23p3(4S3/2o) and the seven lowest excited levels 3s23p3(2D5/2o), 3s23p3(2D3/2o), 3s23p3(2P3/2o), 3s23p3(2P1/2o), 3s3p4(4P5/2), 3s3p4(4P3/2) and 3s3p4(4P1/2) of Cl III, as these can generate resonances within the energy range of the experiment. We were able to identify most of the resonances as belonging to various specific initial levels within the primary Cl III ion beam. Compared to the first five levels, resonant structures in the σPI of excited levels of 3s3p4 appear to have a weaker presence. We have also produced combined theoretical spectra of the levels by convolving the cross sections with a Gaussian profile of experimental width and summing them using statistical weight factors. The theoretical and experimental features show good agreement with the first five levels of Cl III. These features are also expected to elucidate the recent observed spectra of Cl III by Sloan Digital Scan Survey project.

AbstractVernal pools are temporary wetlands that can form during a rainy season, often in Mediterranean climates, and serve as ideal testing grounds to understand species detection using eDNA and how biological communities may shift across time and spatial and environmental heterogeneity. Most vernal pools exhibit high plant and animal diversity and endemism, but due to their ephemeral nature, they are understudied, especially their microorganisms. Habitat destruction and fragmentation creates an urgent need to monitor their biodiversity, but traditional species surveys require time and taxonomic expertise. We conducted a community science‐enabled examination of soil environmental DNA (eDNA) in California's Great Central Valley and assessed the capacity of eDNA to aid biomonitoring. We used metabarcoding of16S,ITS1,CO1,18S, andITS2marker regions to quantify and compare differences in pool communities across two sampling periods (during years with disparate precipitation) and to estimate variation among pools and inundation zones (vernal pool bottom, transitional edge, and grassland upland). We found differences in beta diversity among sampling periods, pools, and inundation zones; alpha diversity was mainly affected by sampling period and zone, but this differed by marker. Numerous taxonomic families varied in abundance and composition among samples, yet vernal pool communities remained distinct from upland grass communities, even between sampling periods differing by 1 year. Turnover in ecologically co‐occurring taxon pairs varied by over 90% between sampling periods in all metabarcodes but plants, which were more stable. Finally, we confirmed substantial concordance between eDNA and traditional inventories of the reserve's plants and presented a case in which we detected one endangered plant species, Colusa grass (Neostapfia colusana), in advance of its emergence. This initial study adds hundreds of new taxon records for California vernal pools and discusses benefits and challenges of using eDNA for biomonitoring within stressful, temporary, or otherwise challenging ecosystems.