This article presents a portrait of the scientific work of the Japanese physical chemist Shin Sato (1928-2022) at Tokyo Institute of Technology from the mid-1950s until 2019. His work included studies in both photochemistry and radiation chemistry with a special emphasis on small molecules, attention given to analogies with the behavior of small molecules under atmospheric condition. Noteworthy is his contribution to a new intuitive semi-empirical method of drawing the Potential Energy Surface of the collisions between an atom and a diatomic molecule, now known as the LEPS Method. He published more on the following: photosensitization reactions of mercury, cadmium, zinc and benzene; insertion of NH radical into the C-H bond of carboxylic acid to form amino acids; the isotope effects of deuterium on the reaction of the hydrogen atom with the hydrogen molecule; ESR studies and calculations of tunneling in bimolecular reactions; developing temperature dependent rate formula for the reactions at temperatures lower than 10 K, lower than the Arrhenius equation that is applicable to temperatures higher than room temperature. Sato published a textbook on quantum chemistry, co-authored a book on photochemistry and radiation chemistry and translated from English two chemistry books. As a teacher he supervised about one hundred students in his laboratories. By his research and teaching he became a bridge between the Eastern and Western scientific and cultural worlds. He had a major impact on intercultural dialogue.

Kuroda Chika was the first Japanese woman to graduate in chemistry. This article describes her early education and subsequent career in chemical research in Japan from 1913, and includes two years in Oxford (1921-1923). Her career as a researcher in The Physical and Chemical Research Institute (RIKEN) and as a professor at Ochanomizu University in Tokyo is described. Kuroda’s organic chemistry studies, specifically the identification of the constitution of plant dyes is described. The status of female education and female employment in Japan during the first half of the twentieth century are also considered. Later in her career the achievements of Kuroda Chika were acknowledged with prestigious prizes and awards.

This research studies two translations of Henry Enfield Roscoe's chemistry book of 1872 into Japanese (1873) and Hebrew (1929). Roscoe's original chapter on candle burning is presented, in which he manifested his attitude to chemical experiments. The Japanese and Hebrew historical backgrounds of the translations, as well as their cultural and linguistic aspects are discussed. Roscoe's relations with Japanese scholars are presented. The study moves between events in three countries, England, Japan and Israel. The importance and complexity of translation of science and its later results are discussed.

This work presents chemistry studies of the Japanese scholar Udagawa Youan (1798-1846), specifically, his pioneering book Seimi Kaiso, introduction to Chemistry, and includes a short biography of Youan. The first aim of this work is to present Youan's contribution to Western chemistry in Japan. Youan studied many Western books and listed their authors. The new terms he invented for chemistry in Japanese influenced the development of chemistry writing and application in Japan. The seven books of Seimi Kaiso that were published during 1837-1847 and republished with annotation in Japanese in 1975 are discussed in this article. The impact of Youan' terminology on the history chemistry writing in the nineteenth and twentieth centuries is discussed. The conditions of knowledge transfer among Japanese and Western scholars were very different. Youan had severe difficulties facing the strict attitude of the Tokugawa authorities toward studying and distributing knowledge coming from foreign countries. The later development of Japanese chemistry language and studies is also described.

We present here the life and work of Shmuel Malkin (1934–2017), an accomplished scientist and a gifted musician who touched the lives of many around the world. His early scientific work addressed the dynamics of light harvesting and electron transport in photosynthesis. Later, he used photoacoustic and photothermal methodologies to explore all aspects of photosynthesis. As a musician, Shmuel played the piano often for family and friends but after his formal retirement, he produced a body of original musical compositions, many of which were performed publicly. Throughout his life, Shmuel was a caring and deeply thoughtful man, respected and loved by colleagues, family, and friends. This tribute presents a summary of Shmuel’s work as well as remembrances written by his wife, Nava Malkin, their son, Eyal Malkinson, and many of his colleagues: Michael Havaux from France; Sandra and Marcel Jansen from Ireland; David Cahen, Marvin Edelmann, Joop and Onnie de Graaf, Jonathan Gressel, Uri Pick, Yona Siderer, and Elisha Tel-Or from Israel; Ulrich Schreiber from Germany; James Barber and Alison Telfer from the UK; Govindjee, Stephen Herbert and Thomas Sharkey from the USA. Minnie Ho and Iris Malkin of the USA wrote contributions about Shmuel’s music.

Japanese scholars in the eighteenth and nineteenth centuries concentrated their efforts translating Western scientific books. Due to fact that only Dutch merchants were permitted to trade with Japan, mainly books in Dutch were introduced into Japan. Thus Dutch translations of books from England, Germany, France, Sweden and Italy were imported. Udagawa Youan was a member of a Japanese family of Chinese medicine doctors and Dutch translators. In the following chapters I outline his life, his vast scope of translations, and present one of his translations , Kouso Seimika , “Chemistry of the Element of Light”: On light and heat reactions with substances, based on a paragraph of the Dutch edition of Antoine Lavoisier’s Traité Élémentaire de Chimie . Youan’s skills were shown in coining new terms in his largest book Seimi Kaiso for which more than twenty-five books of foreign authors are cited as origin for its translation. The wide range of knowledge transfer between scholars of different countries in Europe emphasizes its contrast with the isolation of translation work of the Japanese scholars. Flow of scientific knowledge from Europe to Japan in the nineteenth century is manifested. Udagawa Youan’s text Kouso Seimika explains the reactions of heat and light with matter, plants, animals and mankind as was understood in Lavoisier time.

Electron paramagnetic resonance of spinach chloroplasts given a series of laser flashes, n = 0, l, ..., 6, at room temperature and rapidly cooled to -1400C reveals a signal pos- sessing at least 16 and possibly 21 or more, hyperfine lines when observed below 35 K. The spectrum is consistent with a pair of antiferromagnetically coupled Mn ions, or possibly a tetramer of Mn ions, in which Mn(III) and Mn(IV) oxidation states are present. The intensity of this signal peaks on the first and fifth flashes, suggesting a cyclic change in oxidation state of period 4. The mul- tiline signal produced on the first flash is not affected by the elec- tron transport inhibitor 3-(3,4-dichlorophenyl)-l,l-dimethylurea but is abolished by agents that influence the state of bound man- ganese, such as incubation with alkaline Tris, or dithionite, and by extraction with cholate detergent in the presence of ammonium sulfate. These results indicate that the paramagnetic signal is mon- itoring oxidation state changes in the enzyme involved in oxidation of water. The oxidation of water to form molecular oxygen during the light reactions of photosynthesis in green plants and algae serves as the principal source of oxygen in the atmosphere. Although the light-induced reactions in photosynthetic orga- nisms have been studied in great detail with much success, the species that binds two water molecules and extracts four elec- trons and four protons, by an as yet unknown mechanism, has not been identified. Recently, it was reported that oxygen ev- olution is reversibly lost from thylakoid membranes when a protein containing 2 Mn ions is removed with the aid of cholate detergent (1); 85% of the original oxygen yield could be restored upon reconstitution of this Mn protein into.the depleted thy- lakoid membranes. The structure of this protein and the mech- anism by which it operates are currently unknown. A widely

This paper investigates the state-of-the-art of organic food with respect to the law (certification, inspection, and labelling), the market, the customer, and organic food itself.In spite of research work carried out on different aspects of organic food, there is not yet a method/methods for routine use in authentication of organic food products. The issues of organic food safety and potential nutritional benefits are also under study as controversial claims.Research work to support and meet the needs of farmers and markets concerning claims on authenticity, safety and nutritional values of organic crops is necessary and discussed in this paper.

The origin of thermoluminescence A band emitted from Photosystem II was studied by analyzing the dependence of the charging efficiency of the A band by continuous illumination at −196°C on preillumination flashes and DCMU treatment. The following results were obtained. (1) Illumination at −196°C given after preillumination flashes at 15°C altered the normal oscillation pattern of the flash-induced B band in dark-adapted thylakoids having emission maxima at the first and fifth flashes to a very different pattern showing huge maxima at the second and sixth flashes. (2) The charging efficiency of the A band by the illumination at −196°C oscillated in parallel with the altered oscillation pattern of the B band. (3) Addition of DCMU after preillumination flashes but prior to illumination at −196°C strongly enhanced the A band at the expense of the B band, and the oscillation pattern of the A band thus obtained was almost identical to that of the B band observed in the absence of DCMU. (4) These phenomena were satisfactorily explained by a sequential formation of specified positive and negative charges at the reaction center by flash preillumination and continuous illumination at −196°C, respectively. (5) In CaCl 2 -washed Photosystem II particles, where the S 3 -S 4 transition is blocked by removal of the three extrinsic proteins, the A-band height as a function of the flash number increased up to second flash but stopped oscillating thereafter. Based on these results, it was concluded that the A band of thermoluminescence arises from recombination between the negative charge on the primary quinone acceptor of Photosystem II (Q A − ), and the positive charge on the S 3 state of the O 2 -evolving system.

X‐ray diffraction studies have been carried out on a single crystal of the photosynthetic inhibitors N‐(3,4‐dichlorophenyl)‐N′‐dimethylurea (DCMU) and its newly synthesized spin‐labeled analog N‐(3,4‐dichlorophenyl)‐N′‐(3,3,5,5‐tetramethylpiperidine‐4‐oxyl)‐urea (DTPU). The synthesis of DTPU as well as its crystallographic data are reported. The crystal system of both compounds is monoclinic with a space group P 2 1 / c . The cell constants of DCMU are a = 7.759(1), b = 14.737(3), c = 9.233(2) Å, β = 100.99(6)°; of DTPU they are a = 6.976(1), b = 11.998(2), c = 23.585(3) Å, β = 91.38(5)°. Comparison of conformational parameters of DCMU and DTPU reveal differences in the dihedral angle between the aromatic ring and the ureido plane. The measured volumes of DCMU and DTPU are 259.1 and 493.3 Å 3 , respectively. These figures suggest the size of the binding site of the inhibitors in the photosynthetic membrane.

The effect of 2,3-dimercaptopropan-1-ol (BAL) on photosynthetic electron transport was studied in Oscillatoria limnetica cells as well as in spinach chloroplasts. Preincubation of the cyanobacterial cells with BAL under aerobic conditions caused inhibition of the sulfide-dependent H2 evolution. The inhibited site was bypassed by N,N,N′,N′-tetramethyl-p-phenylene diamine. Similarly, NADP photoreduction by spinach chloroplasts was inhibited by BAL pretreatment and restored by the addition of reduced 2,6-dichlorophenol-indophenol. These results accord previous data demonstrating damage of mitochondrial Rieske iron-sulfur protein after BAL treatment (Slater, E.C. and De Vries, S. (1980) Nature 288, 717–718). However, in chloroplasts there was no change in the Rieske center ESR spectrum after BAL treatment. When added anaerobically, BAL served as an electron donor for light-dependent, H2 evolution in cyanobacteria or for NADP reduction in spinach chloroplasts. These reactions were insensitive to 3-(3′,4′-dichlorophenyl)-1,1dimethylurea (DCMU), but sensitive to 2,5-dibromothymoquinone or to aerobic pretreatment with BAL. The Rieske protein ESR signal of chloroplasts (g = 1.89) which disappeared upon illumination in the presence of DCMU and methyl viologen, was restored by BAL. It is suggested that as opposed to its aerobic inhibitory effect, BAL donates electrons to the Rieske protein under anaerobic conditions.

A new spin label nitroxide which is also a herbicide of the urea family has been synthesized. The nitroxide spin label derivative of diuron (ditempuron, DTPU) inhibits electron flow at the site of diuron inhibition of photosystem II (PSII) activity, and it is also reduced by electron flow from one of the first acceptors of PSII. The reduction of the nitroxide group of DTPU is inhibited by diuron or by trypsin treatment of the thylakoids but not by DNP-INT or DBMIB. It is suggested that DTPU binds specifically to and accepts electrons at the Qв site.

This chapter presents the electron paramagnetic resonance (EPR) evidence for the involvement of a discrete manganese (Mn) cluster in O2 evolution. The requirement for Mn in the four electron oxidation of two water molecules to form molecular oxygen by photosynthesis is well established. A minimal quantity of 4 Mn ions per PS-II unit appears to be required for full O2 evolution capacity, based upon Mn extraction and the enrichment of Mn in PS-II preparations. It is widely accepted that this Mn is associated with protein that is bound to the inner surface of the thylakoid membrane. Illumination of dark-adapted chloroplasts by a train of short flashes results in the periodic release of O2 after each fourth flash. A newly discovered EPR signal in membranes of spinach, a green alga, and a blue-green alga, is observable below 8 K and exhibits hyperfine structure characteristic of an even-spin cluster of two or four Mn ions.

The γ-radiolysis of the liquid nitrogen–methane system has been investigated. As products, hydrogen cyanide, ethane, and the basic compounds were observed. The G(HCN) attained was 0.08 at higher concentrations of methane, while the G(basic compounds) was found to be in the order of 0.5. In order to explain these results, different precursors for the HCN and the basic compounds are considered.