In this paper, the authors examine the characteristics of threatening and otherwise inappropriate letters sent to Hollywood celebrities. Such communications, known colloquially as “nut mail,” “hate mail,” obscene letters, and threat letters, are received by the famous in enormous volume. We studied approximately 1800 such letters to entertainment celebrities from 214 subjects, who averaged 8 letters apiece. We quote excerpts from these letters, describe objects enclosed with them, and provide quantitative data on such variables as the form, appearance, volume, and duration of such letters; the subject's perceived relationship to the celebrity; the thematic content of the letters; and the messages and threats they communicate. Comparisons between 107 subjects who pursued encounters with the celebrities and 107 who did not revealed 15 factors associated with such pursuit. Contrary to expectation, the presence or absence of threats was not associated with pursuit behavior.

The authors examine the characteristics of threatening and otherwise inappropriate communications sent to members of the U.S. Congress by a sample of 86 subjects, 20 of whom threatened assassination. We quote excerpts from these letters and provide quantitative data on such variables as the volume, duration, form, and appearance of such communications; the enclosures; the subjects' perceived relationships to the recipients; the thematic content of the communications; and the messages and threats communicated. Comparisons between 43 subjects who pursued encounters with members of Congress and 43 who did not revealed 17 factors associated with such pursuit. In this population, threateners were significantly less likely to pursue an encounter than inappropriate letter writers who did not threaten, regardless of the type of threat or the harm threatened. Inappropriate letters to members of Congress are compared with those directed to Hollywood celebrities. Mentally disordered persons writing to public figures often mention and sometimes threaten public figures other than those to whom the letters are addressed, which raises important issues regarding notification of endangered third parties and the sharing of information among protective agencies.

The kinetics of oxidation and reduction of P700, plastocyanin, cytochrome f and cytochrome b-563 were studied in a reconstituted system consisting of Photosystem I particles, cytochrome bf complex and plastocyanin, all derived from pea leaf chloroplasts. Decyl plastoquinol was the reductant of the bf complex. Turnovers of the system were initiated by laser flashes. The reaction between oxidised P700 and plastocyanin was non-homogeneous in that a second-order rate coefficient of c. 5×10(-7) M(-1) s(-1) applied to 80% of the P700(+) and c. 0.7×10(7) M(-1) s(-1) to the remainder. In the presence of bf complex, but without quinol, the electron transfer between cytochrome f and oxidised plastocyanin could be described by a second-order rate coefficient of c. 4×10(7) M(-1) s(-1) (forward), and c. 1.6×10(7) M(-1) s(-1) (reverse). The equilibrium coefficient was thus 2.5. Unexpectedly, there was little reduction of cytochrome f (+) or plastocyanin(+) by electrons from the Rieske centre. With added quinol, reduction of cytochrome b-563 occurred. Concomitantly, electrons appeared in the oxidised species. It was inferred that either the Rieske centre was not involved in the high-potential chain of electron transfer events, or that, only in the presence of quinol, electrons were quickly passed from the Rieske centre to cytochrome f (+). Additionally, the presence of quinol altered the equilibrium coefficient for the cyt f/PC interaction from 2.5 to c. 5. The reaction between quinol and the bf complex was describable by a second-order rate coefficient of about 3×10(6) M(-1) s(-1). The pattern of the redox reactions around the bf complex could be simulated in detail with a Q-cycle model as previously found for chloroplasts.

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Rate-coefficients describing the electron transfer reactions between P700 and plastocyanin, between cytochromef in cytochromebf complexes and plastocyanin, and between decyl plastoquinol and cytochromebf complexes were determined as a function of pH in the range 4-10 from flash-induced absorbancy changes at four wavelengths. The reactions between P700 and plastocyanin, and between cytochromef and plastocyanin were optimised when there was electrostatic interaction between ionised acidic groups in plastocyanin with a pKa of 4.3-4.7 and ionised basic constituents in P700 (assumed to be in the PSI-F subunit) and in cytochromef, with a pKb of 8.9-9.4. The basic groups are thought to be lysine rather than arginine. This mechanism agrees with that inferred from effects of ionic strength changes on rate-coefficients. The relation between the second-order rate-coefficient for decyl plastoquinol oxidation by thebf complex and pH was characterised by a pKa of 6.1. This is interpreted as showing that the anion radical form of that quinol, which has a pKa of 6, and which becomes progressively protonated when pH is changed from 7 to 5, is essential to reduce cytochromeb-563 (low potential) during quinol oxidation. Above pH 9, permanent effects were observed on this rate-coefficient, which were absent in the reactions between P700, plastocyanin and cytochromef.

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Neutral Red has been shown to undergo electrochemical and photoelectrochemical reactions in aqueous solution. At a pH above the pK,, the dye was oxidized with the loss of one proton with each electron. Similarly the protonated dye was oxidized at pH values below the pK,. Over the pH range examined, 1.0-9.2, Neutral Red was reduced with one proton being gained with each electron. The neutral radical which was formed could be further reduced. When the pH was above the pK, the dye was reduced by an H e e H mechanism, and when the pH was below the pK, the reduction proceeded by an H e H e mechanism with the possibility of further protonation.On a platinum electrode, Neutral Red underwent a photoelectrochemical oxidation at pH 7.2. The voltammogram showed a broad peak centred at 0 V (s.c.e.).Neutral Red, viz. 3-amino-7-dimethylamino-2-methylphenazine, has long been flyJbfe used as a pH indicator in biological studies'because its red-yellow colour change at h H, pK, 6.7 falls in the pH range close to that Neurrai Red of biological media. However, problems were encountered in studies of photosynthetic reactions when Neutral Red was used as a spectroscopic probe of the internal pH of thylakoidse3 The observed changes in the probe's absorbance were consistent with acidification of the medium but were much larger than expected. One explanation is that the dye was protonated preferentially in the aqueous phase; this indicated a variation of activity with l~c a t i o n .~ Other explanations for these results are that the unexpected decrease in the absorbance was due to Neutral Red acting as an artificial electron donor or acceptor in the photosynthetic reactions, and that the decrease was due to photoelectrochemical reactions of Neutral Red. As the dye absorbs light, it may undergo a charge-transfer reaction with species generated in the photosynthetic reactions.In concentrated acid solutions Havemann et aL4 examined solutions of sn2 + ions and Neutral Red at two pH values. At pH 0.5, where 75 "/,f the dye was in the