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Organic photovoltaics (OPVs) show great promise for both outdoor and indoor applications. However, there remains a lack of understanding around the stability of OPVs, particularly for indoor applications. In this work, the photostability of the poly[(thiophene)‐alt‐(6,7‐difluoro‐2‐(2‐hexyldecyloxy)quinoxaline)]:2,2′‐((2Z,2′Z)‐((4,4,9,9‐tetrahexyl‐4,9‐dihydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐2,7‐diyl)bis(methanylylidene))bis(3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile blend is investigated for both outdoor and indoor applications. Photostability is found to vary drastically with illumination intensity. Devices under high‐intensity white light‐emitting diode (LED) illumination, with their short‐circuit current density (JSC) matching JSC–EQE for AM1.5 G illumination, lose 42% of their initial performance after 30 days of illumination. Contrastingly, after almost 47 days of illumination devices under 1000 lux white LED illumination show no loss in performance. The poor photostability under 1 sun illumination is linked to the poor photostability of IDIC. Through Raman spectroscopy and mass spectrometry, IDIC is found to suffer from photoisomerization, which detrimentally impacts light absorption and carrier extraction. In this work, it is highlighted that under low light levels, the requirement of intrinsic material photostability may be less stringent.

Abstract Ship present‐weather reports from 1950 to 2019 are used to assess trends in the reporting of precipitation occurrence over the global oceans. Annual reported precipitation frequency shows statistically significant positive trends of up to ∼15% per decade throughout most ocean areas equatorward of 45°. However, latitudes poleward of 45° are dominated by negative trends, some areas of which meet the 95% confidence threshold. Nine smaller regions were subjectively selected for further investigation, revealing that the observed trends, both positive and negative, are often but not always nearly linear, with the amplitude of interannual fluctuations usually being much larger than that expected from random sampling error alone. The annual time series reveal that four comparatively dry areas are associated with the largest overall positive trends, ranging from 8.3% to 12.8% (relative) per decade. Trends were also computed separately for each season, revealing remarkable overall consistency in trends across seasons.

IKZF1 encodes the transcription factor IKAROS, a zinc finger DNA-binding protein with a key role in lymphoid lineage development. IKAROS plays a critical role in the development of lineage-restricted mature lymphocytes. Deletions within IKZF1 in B-cell acute lymphoblastic leukemia (B-ALL) lead to a loss of normal IKAROS function, conferring leukemic stem cell properties, including self-renewal and subsequent uncontrolled growth. IKZF1 deletions are associated with treatment resistance and inferior outcomes. Early identification of IKZF1 deletions in B-ALL may inform the intensification of therapy and other potential treatment strategies to improve outcomes in this high-risk leukemia.

Misfolding of the microtubule-binding protein tau into filamentous aggregates is characteristic of many neurodegenerative diseases such as Alzheimer's disease and progressive supranuclear palsy. Determining the structures and dynamics of these tau fibrils is important for designing inhibitors against tau aggregation. Tau fibrils obtained from patient brains have been found by cryo-electron microscopy to adopt disease-specific molecular conformations. However, in vitro heparin-fibrillized 2N4R tau, which contains all four microtubule-binding repeats (4R), was recently found to adopt polymorphic structures. Here we use solid-state NMR spectroscopy to investigate the global fold and dynamics of heparin-fibrillized 0N4R tau. A single set of 13C and 15N chemical shifts was observed for residues in the four repeats, indicating a single β-sheet conformation for the fibril core. This rigid core spans the R2 and R3 repeats and adopts a hairpin-like fold that has similarities to but also clear differences from any of the polymorphic 2N4R folds. Obtaining a homogeneous fibril sample required careful purification of the protein and removal of any proteolytic fragments. A variety of experiments and polarization transfer from water and mobile side chains indicate that 0N4R tau fibrils exhibit heterogeneous dynamics: Outside the rigid R2-R3 core, the R1 and R4 repeats are semirigid even though they exhibit β-strand character and the proline-rich domains undergo large-amplitude anisotropic motions, whereas the two termini are nearly isotropically flexible. These results have significant implications for the structure and dynamics of 4R tau fibrils in vivo.

Jewish Community Action (JCA) is a 501(c)(3) organization based in St. Paul, Minnesota, that, in collaboration with Black, Indigenous, and people of color (BIPOC)-led groups, equips Jewish people residing in the state to advocate for racial and economic justice. Community education and outreach are central to this work. JCA's Decriminalizing Communities Campaign, in particular, invites participants to transform the ways we conceive of public safety apart from systems of surveillance, incarceration, and detention. The Education Basebuilding Circles began in 2018, expanding the curriculum developed by Showing Up for Racial Justice (SURJ) in response to the legacy of police violence in the wake of the killing of Philando Castile. The circles use a popular education model to bring together adult learners by implementing a 6-week curriculum that examines the intersections of the criminal justice and immigration enforcement apparatus. This article summarizes that curriculum and provides examples of activities that effectively engage learners in self-reflection, community building, and action planning.

The current standard method for amino acid signal identification in protein NMR spectra is sequential assignment using triple-resonance experiments. Good software and elaborate heuristics exist, but the process remains laboriously manual. Machine learning does help, but its training databases need millions of samples that cover all relevant physics and every kind of instrumental artifact. In this communication, we offer a solution to this problem. We propose polyadic decompositions to store millions of simulated three-dimensional NMR spectra, on-the-fly generation of artifacts during training, a probabilistic way to incorporate prior and posterior information, and integration with the industry standard CcpNmr software framework. The resulting neural nets take [1H,13C] slices of mixed pyruvate-labeled HNCA spectra (different CA signal shapes for different residue types) and return an amino acid probability table. In combination with primary sequence information, backbones of common proteins (GB1, MBP, and INMT) are rapidly assigned from just the HNCA spectrum. [ABSTRACT FROM AUTHOR]

Vietnamese Ukrainians are a largely unstudied identity group that has recently attracted attention due to the impacts of the Russo-Ukrainian War. Our study examines Vietnamese-Ukrainian bicultural identity as experienced by 10 university student refugees of the war in 2022–23. Researchers conducted semi-structured ethnographic interviews in which each participant examined identity formation experiences as second-generation Vietnamese Ukrainians. Participants also reflected upon the impacts to ethnic identity self-awareness that resulted from their unexpected return migration to Vietnam as student refugees of war. The cohort of study participants created a tight-knit Vietnamese-Ukrainian return diaspora in an environment conducive to self-reflection and exploration of their ongoing ethnic identity journeys. In our study, we argue that the ethnic identity formation of young Vietnamese Ukrainians relies on the active construction of intercultural personhood as an adaptation to transnational mobility and change. [ABSTRACT FROM AUTHOR]

Organic photovoltaics (OPVs) show great promise for both outdoor and indoor applications. However, there remains a lack of understanding around the stability of OPVs, particularly for indoor applications. In this work, the photostability of the poly[(thiophene)‐alt‐(6,7‐difluoro‐2‐(2‐hexyldecyloxy)quinoxaline)]:2,2′‐((2Z,2′Z)‐((4,4,9,9‐tetrahexyl‐4,9‐dihydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐2,7‐diyl)bis(methanylylidene))bis(3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile blend is investigated for both outdoor and indoor applications. Photostability is found to vary drastically with illumination intensity. Devices under high‐intensity white light‐emitting diode (LED) illumination, with their short‐circuit current density (JSC) matching JSC–EQE for AM1.5 G illumination, lose 42% of their initial performance after 30 days of illumination. Contrastingly, after almost 47 days of illumination devices under 1000 lux white LED illumination show no loss in performance. The poor photostability under 1 sun illumination is linked to the poor photostability of IDIC. Through Raman spectroscopy and mass spectrometry, IDIC is found to suffer from photoisomerization, which detrimentally impacts light absorption and carrier extraction. In this work, it is highlighted that under low light levels, the requirement of intrinsic material photostability may be less stringent. [ABSTRACT FROM AUTHOR]