This article summarizes the present state of knowledge about the organization of the water oxidizing polypeptide complex of photosynthesis and the mechanism of its operation. Spectacular advances have been made in recent years, but many questions remain to be answered. Among them are those concerned with the organization and binding of the functional Mn, its specific role in the oxidant storage that precedes the formation of one oxygen from two water molecules, and its cooperation with other redox-active constituents. Much is still to be learned also about the function of the individual polypeptides and about the role of the cofactors Ca(2+) and Cl(-). Differences between the organization of the water oxidizing complexes in green plants and cyanobacteria suggest, furthermore, that in vivo their water oxidizing mechanisms must operate under different, still unrecognized constraints.
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http://dx.doi.org/10.1104/pp.88.1.1 | DOI Listing |
J Am Chem Soc
January 2025
Department of Chemistry, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea.
Epoxides are versatile chemical intermediates that are used in the manufacture of diversified industrial products. For decades, thermochemical conversion has long been employed as the primary synthetic route. However, it has several drawbacks, such as harsh and explosive operating conditions, as well as a significant greenhouse gas emissions problem.
View Article and Find Full Text PDFBraz J Biol
January 2025
Embrapa Agrobiologia, Seropédica, RJ, Brasil.
The objective was to evaluate the sensitivity of Piptadenia gonoacantha seeds to desiccation and storage conditions. The seeds were subjected to artificial drying in a forced air convection oven (39.7 °C ± 0.
View Article and Find Full Text PDFCien Saude Colet
January 2025
Programa de Pós-Graduação em Administração, Universidade Federal de Viçosa. Av. Peter Henry Rolfs s/n, Campus Universitário. 36570-000 Viçosa MG Brasil.
This study aimed to understand the impact of municipal basic sanitation policies and plans on the rate of access to drinking water and sewage services. For this, data were collected from the 853 municipalities of Minas Gerais regarding the provision of sanitation, as well as socioeconomic, quality of life and demographic indicators, treated with the t-test techniques for differences between means and Propensity Score Matching. The results revealed the need for greater sanitation planning in the state since a significant portion of municipalities do not have formal planning instruments for the sector.
View Article and Find Full Text PDFPLoS One
January 2025
Alliance for Research in Exercise Nutrition and Activity (ARENA), Allied Health and Human Performance, University of South Australia, Adelaide, Australia.
Background: Cold-water immersion (CWI) has gained popularity as a health and wellbeing intervention among the general population.
Objective: This systematic review and meta-analysis aimed to evaluate the psychological, cognitive, and physiological effects of CWI in healthy adults.
Methods: Electronic databases were searched for randomized trials involving healthy adults aged ≥ 18 years undergoing acute or long-term CWI exposure via cold shower, ice bath, or plunge with water temperature ≤15°C for at least 30 seconds.
PLoS One
January 2025
Department of Physiology and Biochemistry, Faculty of Physical Education and Sport Science, Wroclaw University of Health and Sport Sciences, Wroclaw, Poland.
The purpose of this study was to determine the effective warm-up protocol using an added respiratory dead space (ARDS) 1200 ml volume mask to determine hypercapnic conditions, on the swimming velocity of the 50 m time trial front crawl. Eight male members of the university swimming team, aged 19-25, performed three different warm-up protocols: 1) standardized warm-up in water (WUCON); 2) hypercapnic warm-up in water (WUARDS); 3) hypercapnic a 20-minute transition phase on land, between warm-up in water and swimming test (RE-WUARDS). The three warm-up protocols were implemented in random order every 7th day.
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