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Hollow nanostructures keep attracting intense interest as multifunctional materials, especially in energy storage and conversion technologies. We introduce a convenient anion exchange method for the synthesis of metal sulfide nanoboxes (NBs) from Co, Co–Fe, and Ni–Fe Prussian blue (PB) nanocubes (referred to as Co–PB, Co–Fe–PB, and Ni–Fe–PB NCs) as templates. Analytical characterizations show that anionic exchange processes between S2–and CN–lead to the formation of metal sulfide nanobox heterostructures (referred to as Co–S@PB, Co–Fe–S@PB, and Ni–Fe–S@PB NBs). The Co–Fe–S@PB NBs were characterized in detail with a wide range of analytical techniques, including X-ray photoelectron spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). Furthermore, postcatalytic XAS and XPS studies indicated that the in situ formation of Co–Fe oxides/hydroxides during the oxygen evolution reaction (OER) provided active species of the Co–Fe–S@PB NBs, while Fe(CN)63–did not play a role in the catalytic activity. Together with their advanced morphology, this resulted in a superior OER performance of the as-prepared Co–Fe–S@PB NBs in comparison with RuO2and other standards. Co–Fe–S@PB NBs excelled through a low overpotential of 286 mV at 10 mA/cm2, a small Tafel slope value of 37.84 mV dec–1, and high durability over the operational period of 33 h at 10 mA/cm2. Moreover, we applied our strategy to produce new double-layered (Co, Fe)9S8@MoS2nanoboxes (referred to as Co–Fe–Mo–S NBs). The fine-tuned heterostructured nanoboxes are promising for hybrid electrodes due to their high dual OER and hydrogen evolution reaction (HER) activity throughout the pH range.

While loading of cocatalysts is one of the most widely investigated strategies to promote the efficiency of photoelectrodes, the understanding of their functionality remains controversial. We established new hybrid molecular photoanodes with cobalt-based molecular cubane cocatalysts on hematite as a model system. Photoelectrochemical and rate law analyses revealed an interesting functionality transition of the {Co(II)4O4}-type cocatalysts. Their role changed from predominant hole reservoirs to catalytic centers upon modulation of the applied bias. Kinetic analysis of the photoelectrochemical processes indicated that this observed transition arises from the dynamic equilibria of photogenerated surface charge carriers. Most importantly, we confirmed this functional transition of the cocatalysts and the related kinetic properties for several cobalt-based molecular and heterogeneous catalysts, indicating wide applicability of the derived trends. Additionally, complementary analytical characterizations show that a transformation of the applied molecular species occurs at higher applied bias, pointing to a dynamic interplay connecting molecular and heterogeneous catalysis. Our insights promote the essential understanding of efficient (molecular) cocatalyzed photoelectrode systems to design tailor-made hybrid devices for a wide range of catalytic applications.

The aim of the present research was to evaluate the sexual behavior of male sheep during the sexual resting period while exposed to anovulatory females treated with an intravaginal sponge impregnated with progesterone (P4) in northern Mexico. The study took place in northern Mexico (26º N), during the month of March, multiracial rams (n=8, 24–48 mo.) were divided in two homogeneous groups (n=4 each) regarding live weight, body condition score, scrotal circumference and smell, and randomly allocated in two experimental treatments: 1) Males exposed to anovulatory females (n=20) with 20mg of P4 sponges (M20), and 2) Males exposed to anovulatory females (n=20) with 10mg of P4 sponges (M10). Sexual behavior tests were performed in both groups of males by experienced technicians (2 h x 2 d, on days 11 and 12 of the experimental period. Sexual behaviors included flehmen, ano-genital sniffing, approaches and mount attempts. The sexual behavior data was divided in appetitive sexual behaviors [ASB: flehmen, approaches, sniffing (bodily or ano-genital) approaches and vocalizing]; consummatory sexual behaviors (CSB: mount attempts, mounting with erection and mounting with ejaculation). The sexual behavior data were evaluated by X2, using the SYSAT 12.0 statistics program. The largest ASB was shown by the M10 group (64% vs 35%, P0.05) was observed between experimental groups. These findings suggest that males improve their appetitive sexual behaviors (ano-genital sniffing and flehmen), when exposed to ewes treated with 20mg of progesterone.

Parkinson’s disease (PD) is a neurodegenerative condition, which compromises the motor functions and causes the alteration of some executive brain functions. The presence of changes in cognitive symptoms in PD could be due to the procedure of deep brain stimulation (DBS). We searched in several databases for studies that compared performance in executive function tests before and after the DBS procedure in PE and then performed a meta-analysis. After the initial search, there were 15 articles that specifically evaluated the functions of verbal fluency, working memory, cognitive flexibility, abstract thinking, and inhibition. It was found that there were differences in the evaluation of the cognitive functions in terms of the protocols, which generated heterogeneity in the results of the meta-analysis. Likewise, a tendency to diminish functions like verbal fluency and inhibition was found, being this consistent with similar studies. In the other functions evaluated, no difference was found between pre- and postsurgery scores. Monitoring of this type of function is recommended after the procedure.

The title compound is prepared by solid state reaction of a stoichiometric mixture of SrCO3, RuO2, and Eu2O3(Pt crucible, 1483 K, 24 h).