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Reactive sulfane sulfur species such as persulfides (RSSH) and H2S2 are important redox regulators and closely linked to H2S signaling. However, the study of these species is still challenging due to their instability, high reactivity, and the lack of suitable donors to produce them. Herein we report a unique compound, 2H-thiopyran-2-thione sulfine (TTS), which can specifically convert H2S to HSOH, and then to H2S2 in the presence of excess H2S. Meanwhile, the reaction product 2H-thiopyran-2-thione (TT) can be oxidized to reform TTS by biological oxidants. The reaction mechanism of TTS is studied experimentally and computationally. TTS can be conjugated to proteins to achieve specific delivery, and the combination of TTS and H2S leads to highly efficient protein persulfidation. When TTS is applied in conjunction with established H2S donors, the corresponding donors of H2S2 (or its equivalents) are obtained. Cell-based studies reveal that TTS can effectively increase intracellular sulfane sulfur levels and compensate for certain aspects of sulfide:quinone oxidoreductase (SQR) deficiency. These properties make TTS a conceptually new strategy for the design of donors of reactive sulfane sulfur species. Reactive sulfane sulfur species such as persulfides and H2S2 are important redox regulators and linked to H2S signaling, but their study is hindered by a lack of suitable donors to produce them. Here, the authors report 2H-thiopyran-2-thione sulfine (TTS), a compound which can specifically convert H2S to HSOH, and then to H2S2 in the presence of excess H2S. [ABSTRACT FROM AUTHOR]

We consider a filtration on the cohomology of the structure sheaf indexed by (not necessarily reduced) divisors “at infinity”. We show that the filtered pieces are functorial with respect to transfers, have fpqc descent, and are so called cube invariant. In the presence of resolution of singularities and weak factorisation they are invariant under blowup “at infinity”. As such, they lead to a realisation functor from Kahn, Miyazaki, Saito and Yamazaki’s category of motives with modulus over a characteristic zero base field. [ABSTRACT FROM AUTHOR]

Background: With blood products being a limited and expensive resource within the healthcare system, there is an ever-increasing emphasis on judicial and appropriate use. AIMS: To evaluate whether implementing contemporary society recommendations on restrictive transfusion policies would reduce inappropriate use of red blood cell transfusions, by evaluating the effect of a staff educational campaign. Methods: An audit of peri-partum red cell concentrate (RCC) transfusion practice within a tertiary obstetric unit was undertaken, covering a 1-year period (2015), examining data related to transfusion prescribing practices. Subsequently, an educational programme was held for clinical and laboratory staff which aimed to bring practice in line with society guidelines. A repeat audit covering another 1-year period (2018) was undertaken. Results: The number of RCC units of transfused reduced by 49% between 2015 and 2018 (426 to 218). The number of patients receiving transfusion dropped from 166 in 2018 (1.8% of births) to 119 in 2015 (1.5% of births). Among stable patients who were transfused, the proportion receiving a single unit increased from 6.9 to 53.9%. (p < 0.001). Haematological reassessment between units rose from 13.8 to 80.4% (p < 0.001). Written consent documentation improved (68% in 2018 vs. 38% in 2015) (p < 0.001). Conclusions: The implementation of guidelines has resulted in substantial reduction in RCC transfusions between 2015 and 2018. Fewer women received a blood transfusion, and those who did received fewer units. There is a higher proportion of patients being reassessed between units and receiving single unit transfusions. Recording of consent has improved. [ABSTRACT FROM AUTHOR]

Our visual system relies on memory to store and retrieve goal-relevant structures and information from the environment for the purpose of optimizing the allocation of attention. This concept, referred to as contextual cueing, has been demonstrated using visual search tasks, wherein repeated visual contexts lead to reduced search times compared with random displays. Subsequently, when an unexpected change occurs in the environment, or memory fails, a cognitive expense is incurred as the mind tries to resolve the conflict with the memory of the previous environmental context. How memory resolves these conflicts and is updated is of great interest. Previous studies showed that, without extensive practice, individuals were unable to associate a secondary target location with a previously learned spatial context following the relocation of the initially learned target. Here, we explored variables that could potentially affect contextual learning and relearning, such as display size, crowding, context color, and whether the target switched to a previously occupied or unoccupied location. In a series of four experiments, we find relearning occurring in all instances. Previous research may have suffered from underpowered designs. [ABSTRACT FROM AUTHOR]

We give necessary and sufficient conditions for a cdh sheaf to satisfy Milnor excision, following ideas of Bhatt and Mathew. Along the way, we show that the cdh ∞ -topos of a quasi-compact quasi-separated scheme of finite valuative dimension is hypercomplete, extending a theorem of Voevodsky to nonnoetherian schemes. As an application, we show that if E is a motivic spectrum over a field k which is n-torsion for some n invertible in k, then the cohomology theory on k-schemes defined by E satisfies Milnor excision. [ABSTRACT FROM AUTHOR]

Six novel unsymmetrical diglycolamide (UDGA) ligands have been synthesized and evaluated as solvent extraction reagents for the partitioning of lanthanide (Ln) ions from nitrate media. The partitioning of europium between aqueous phases of varying nitric acid concentrations and a UDGA organic phase has been characterized radiometrically. The stoichiometry and phase-transfer equilibrium constants of the Eu-UDGA complexes extracted into the organic phase have been reported. Luminescence spectroscopy investigations have established the relative stability and stoichiometry of the complexes in acetonitrile. These UDGA ligands have displayed enhanced interfacial activity, which has decreased the necessary equilibration time while maintaining high Ln distribution ratios. [ABSTRACT FROM AUTHOR]

The modern integrated circuit (IC) manufacturing process has exposed the fabless semiconductor industry to hardware Trojans that threaten circuits bound for critical applications. This paper investigates an on-chip sensor's effectiveness for Trojan detection in an application specific integrated circuit (ASIC) and proposes new techniques to improve the sensor's sensitivity to Trojan switching activity. The sensors serve as power supply monitors by detecting fluctuations in their characteristic frequencies due to malicious inclusions (i.e. hardware Trojans) in the circuit under authentication. Our proposed on-chip structure was implemented and fabricated on an ASIC test chip using IBM 90nm technology with controlled hardware Trojans. This work analyzes the impact of both sequential and combinational Trojans with varied partial activity, area, and location on the proposed on-chip structure and demonstrates that stealthy Trojans can be effectively detected with this technique, even when obfuscated by circuit switching activity and process and environmental variations. [ABSTRACT FROM AUTHOR]