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Between 7 and 25 May, 86 monkeypox cases were confirmed in the United Kingdom (UK). Only one case is known to have travelled to a monkeypox virus (MPXV) endemic country. Seventy-nine cases with information were male and 66 reported being gay, bisexual, or other men who have sex with men. This is the first reported sustained MPXV transmission in the UK, with human-to-human transmission through close contacts, including in sexual networks. Improving case ascertainment and onward-transmission preventive measures are ongoing.

International audience; Paternal care is generally, although not exclusively, associated with monogamy in mammals. The Algerian mouse, Mus spretus, is a nocturnal murid living in xeric habitats in northern Africa, the Iberian peninsula and the south of France. We compared the amount of paternal care induced by removing young in Mus spretus and in the polygamous house mouse M. musculus domesticus in terms of the evolution of paternal care during the first 10-days post-partum and absolute (father alone) and relative (both parents) values. We then recovered indirect evidence of young being cared for by males from field data. The results were unambiguous in showing that the two species differed dramatically in paternal behaviour, with no variation being observed during the initial pup development. Mus spretus dedicated half of its time to caring from the young against less than 10% in M. m. domesticus. The former species showed the same number of retrieving acts and direct care bouts both in the presence and in the absence of the mother. Merging these results with field observations of spatial association "male-young" until subadult age, we drew conclusions on the likely occurrence of paternal care in M. spretus. Taken together with our previous results on socio-spatial organisation and pair bonding, we propose that social monogamy is advanced for this species.

International audience; The mating system of murids remains largely unknown, with controversial reports. Reevaluation of previous data reveals monogamous features in the Algerian mouse from the South of France, Mus spretus. To test this hypothesis, we performed dyadic encounters toward three kinds of opponents from the other sex (his/her own mate, a mouse from an unknown pair, and an isolated individual), and compared the results to those of a related acknowledgedly polygynous related species, the house mouse M. musculus domesticus. We expected more affiliative behaviours toward its mate from the M. spretus male, and a higher interest toward unknown females in the house mouse. Females should not exhibit striking differences toward their partner, contrary to their behaviour toward unknown males. Results showed the predicted behaviour for males as well as for females: more amicable, but also sexual, toward its mate for M. spretus male, the unknown protagonists eliciting the greatest social interest in the case of the house mouse.

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The following paper is a continuation of two previous papers in which the melting- and freezing-point curves for two pairs of substances, each of which forms mixed crystals, have already been determined. In the first of these papers mixtures of naphthalene and β -naphthol were examined and found to a form a continuous series of mixed crystals and to give curves of Roozeboom's Type I, in which the melting and freezing points of all mixtures lie between the melting points of the pure substances.

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The object for which the present investigation was undertaken was to study the spontaneous crystallisation of mixtures of two substances which form mixed crystals and possess a minimum, or eutectic, freezing point. According to Cady, naphthalene and monochloracetic acid are such a pair of substances, and possess a minimum melting point of 53°·5 for the eutectic mixture of 29·4 per cent, naphthalene, 70·6 per cent, monochloracetic acid. We have attempted to verify Cady’s freezing and melting point curves, but, although our experiments confirm the former, we were quite unable to verify the latter. Pickering mentions four modifications of monochloracetic acid, and traces the freezing point curves for three of them. Our study of mixtures of monochloracetic acid and naphthalene has not given us the information we expected concerning the composition of the “mixed crystals” which separate spontaneously from a solution, but it has led to interesting results concerning the spontaneous crystallisation of the different modifications of a substance dissolved in another substance which is not polymorphous. The Different Modifications of Monochloracetic Acid and their Mutual Transformations . Microscopic examination of crystals of monochloracetic acid obtained from fusion or solution show clearly that three different modifications α, β , and γ of the acid exist. These modifications have melting points 61˚˙5, 55°, and 50°; they are formed on the microscope slide under different circumstances, each modification yielding rhombs quite distinct from those of the two other modifications. If fused monochloracetic acid be cooled suddenly it crystallises as the γ -modification in rhombs having a plane angle of about 59°. If these rhombs be touched they at once transform into the β -modification and give rhombs having a plane angle of about 72°; or occasionally the γ -rhombs are transformed at once into the stable a-modification of the acid, which exists as broad needles having an acute angle of 43˚. The transformation from γ to α takes place much more rapidly than the transformation from γ to β . Similarly, if rhombs of β are formed on a microscope slide they may be at once transformed into the α -modification by inoculating with a fragment of α . Each transformation is accompanied by a rise of temperature. A remarkable feature of the change is that the more stable modification crystallises with sharp edges in the solid mass of the less stable substance, as though it were growing in a liquid.

Our previous papers on spontaneous crystallisation have dealt with the supersolubility curves, firstly, of pure substances; secondly, of mixtures of two or more substances which do not form mixed crystals; and, finally, with naphthalene and β -naphthol; the last form mixed crystals of the type (l) of Roozeboom, in which the freezingpoints of all mixtures lie between the freezing-points of the pure components. The object for which the present investigation was undertaken was to study the spontaneous crystallisation of two substances which form mixed crystals and possess a minimum or eutectic freezing-point.

In a previous paper by the present authors, it was shown that, for the aqueous solutions of certain salts, a definite curve may be traced which gives the temperature of spontaneous crystallisation for a supersaturated solution of any given strength. “Spontaneous crystallisation” is to be understood to signify that, at and below these temperatures, crystallisation may he started by purely mechanical means. This curve, to which they have given the name of “supersolubility curve” (SH or s H of fig. 1), is, for the salts examined by them, nearly parallel to the solubility curve (ME or m E of fig. 1), and generally separated from it by an interval of about 10°. To use Ostwald’s phraseology, it indicates, on the temperature-concentration diagram, the boundary between the area representing the “metastable” condition, in which crystallisation can only take place in contact with a solid crystal, and the area representing the “labile” condition, in which crystallisation may take place spontaneously. Previous investigators have usually endeavoured to trace the process of crystallisation in alloys, fusion mixtures, and solutions, by determining the constitution of the solid which separates. We have endeavoured rather to determine the changing constitution of the liquid, making use of the refractive index for this purpose. The curve was traced, not only by means of the refractive index, which attains a maximum value at the temperature of spontaneous crystallisation, but also by the development of a dense cloud of crystals, which makes its appearance at the same temperature when the solution is stirred. This we term a “labile” shower, in order to distinguish it from the much thinner “metastable” showers, which may occur before this temperature is reached. Solutions enclosed in sealed tubes, so as to be preserved from chance inoculation by dust of the crystalline solid, cannot be made to crystallise by shaking at any temperature higher than that given by the supersolubility curve.

The behaviour of mixtures of naphthalene and β-naphthol has already been investigated, and the freezing and melting point curves and the curve of spontaneous crystallisation for these mixtures described.* These substances were found to form a continuous series of mixed crystals, on a curve of Roozeboom’s Type 1, the melting and freezing points of all the mixtures lying between the melting points of the pure substances. The behaviour of mixtures of monochloracetic acid and naphthalene was also investigated, for it was stated by Cady that these substances form mixed crystals of Roozeboom’s Type 5, whose melting and freezing point curves exhibit a minimum or eutectic freezing point. Experiments were therefore made with these substances with the object of determining the form of the curve of spontaneous crystallisation, or supersolubility curve, for mixtures of this type. No sign of the formation of any mixed crystals was observed, however, in a lengthy series of experiments, and it was shown that naphthalene and monochloracetic acid give the ordinary V-shaped freezing point curve for the solutions of two substances in each other, similar to that already obtained for mixtures of salol and betol,§ the only new feature being introduced by the existence of three modifications of monochloracetic acid. The monochloracetic acid and naphthalene mixtures having thus failed as an example of mixed crystals possessing a minimum or eutectic freezing point, another attempt was made to obtain a pair of substances with convenient melting points which form mixed crystals and possess the melting and freezing point curves with minimum eutectic point characteristic of Roozeboom’s Type 5.

A case of molluscum contagiosum confined to burn scar is described.