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Sexual ornaments contribute substantially to phenotypic diversity and it is particularly relevant to understand their evolution. Ornaments can assume the function of signals-of-quality that the choosy sex uses to evaluate potential mating partners. Often there are no obvious direct benefits and investment into mate choice is primarily rewarded by beneficial alleles that are inherited to the offspring. Inter-sexual communication via sexual ornaments requires honesty of the sexual signal, yet the question of what maintains honesty remains only partially solved. One solution is that honesty is maintained by trait expression being dependent on individual condition, since condition-dependent trait expression offers an effectively inexhaustible source of genetic variability. Here we test in the highly sexually dimorphic club-legged grasshopper Gomphocerus sibiricus if putative sexual ornaments, in particular the striking front-leg clubs, are more strongly affected by a lipopolysaccharide (LPS) immune challenge than putatively not sexually selected traits. Our results show overall little condition-dependent expression of morphological and song traits, with sexually selected traits exhibiting effects comparable to nonsexually selected traits (with the possible exception of stridulatory file length and syllable-to-pause ratio in advertisement songs). Interestingly, field observations of individuals of lethally parasitized individuals suggest that a very strong environmental challenge can specifically affect the expression of the front-leg clubs. The presence of 1% of males in natural populations with missing or heavily deformed clubs plus 5% with minor club deformations furthermore indicate that there are risks associated with club development during final ecdysis and this might act as a filter against deleterious alleles., (© 2017 Institute of Zoology, Chinese Academy of Sciences.)

Background: Colour polymorphisms are a fascinating facet of many natural populations of plants and animals, and the selective processes that maintain such variation are as relevant as the processes which promote their development. Orthoptera, the insect group that encompasses grasshoppers and bush crickets, includes a particularly large number of species that are colour polymorphic with a marked green-brown polymorphism being particularly widespread. Colour polymorphism has been associated with the need for crypsis and background matching and background-dependent homochromy has been described in a few species. However, when and how different environmental conditions influence variation in colour remains poorly understood. Here we test for effects of background colour and ambient temperature on the occurrence of colour morph switches (green to brown or brown to green) and developmental darkening in the alpine dwelling club-legged grasshopper Gomphocerus sibiricus., Results: We monitored individually housed nymphae across three of their four developmental stages and into the first week after final ecdysis. Our data show an absence of colour morph switches in G. sibiricus, without a single switch observed in our sample. Furthermore, we test for an effect of temperature on colouration by manipulating radiant heat, a limiting factor in alpine habitats. Radiant heat had a significant effect on developmental darkening: individuals under low radiant heat tended to darken, while individuals under high radiant heat tended to lighten within nymphal stages. Young imagoes darkened under either condition., Conclusions: Our results indicate a plastic response to a variable temperature and indicate that melanin, a multipurpose pigment responsible for dark colouration and presumed to be costly, seems to be strategically allocated according to the current environmental conditions. Unlike other orthopterans, the species is apparently unable to switch colour morphs (green/brown) during development, suggesting that colour morphs are determined genetically (or very early during development) and that other processes have to contribute to crypsis and homochromy in this species.

Case reports of 110 patients undergoing pneumonectomy were reviewed to assess value of standard postoperative chest radiography for detection of early complications, consisting mainly of empyema and/or bronchopleural fistula. Most radiologic modifications observed do not represent abnormal findings, although two signs can contribute to the radiologic diagnosis of empyema: the central superimposed air/fluid levels and the secondary mediastinal displacement, but even these signs are inconstant and of late onset. Five signs may be of significance for the diagnosis of bronchopleural fistula: in addition to the two described above there are the rapid fall in principal air/water level, the increase in subcutaneous emphysema and the late onset contralateral alveolar syndrome. The diagnosis of a bronchopleural fistula prior to the development of clinical symptoms was possible in one of two cases.

Twelve cases of emboli to the renal artery (one of which was recurrent) were reviewed. In seven patients, emboli were unilateral and the opposite kidney was functional. In five patients, emboli were bilateral or occurred in a solitary kidney, leading to anuria. Cardiac rhythm disorders were encountered in eight patients and were responsible for emboli in other areas in three. Arteriography in ten patients demonstrated seven complete truncal occlusions (one bilateral), two incomplete truncal occlusions, and one distal embolus. One patient with a distal embolus was treated by heparin alone with satisfactory results. One patient in poor general condition was treated with intraarterial streptokinase, resulting in incomplete lysis of the clot. The five patients with anuria were operated on: four regained satisfactory renal function whereas the other patient died. In five patients without anuria who were operated upon, renal function returned to normal in four, and one patient required nephrectomy. Surgical treatment is imperative with anuria and is indicated in unilateral emboli with a functional contralateral kidney, especially when there is complete occlusion of the renal trunk. If the embolus is recent, intraarterial fibrinolytic treatment or percutaneous embolectomy can be attempted, but these techniques are not of proven efficacy. Patients with distal emboli or contraindications to operation should be treated by anticoagulant therapy, alone or with local fibrinolytic treatment.

In elective or emergency operations 363 short venous or polytetrafluoroethylene grafts were inserted to correct stenosis of haemodialysis grafts. Such stenoses are located in the upper part of the graft or in the receiving vein in 80% of the cases. After 2 years, 74% of the short grafts were still permeable. This original technique has several advantages: the initial venous approach is respected, the graft can be used immediately for dialysis, and the patient's venous "capital" is spared.

Late renal revascularization could be indicated in totally occluded renal artery with hypertension and or renal insufficiency. Six cases of secondary revascularization after occlusion of renal artery are reported here. In three cases severe renovascular hypertension was the indication for renal revascularization. In three other cases, indication was proposed for renal insufficiency. In four cases, renal revascularization for totally occluded renal artery have been beneficial for the patients. In two cases of terminal renal insufficiency, chronical hemodialysis could be suppressed. In the others two cases, hypertension was clearly improved. The criteria for renal revascularization before and during surgery are discussed here. The kidney length, the cortico-medullary ratio at kidney echography, and the visualization of a nephrography during angiography are the principal criteria before surgery for renal revascularization. The macroscopic aspect of the kidney, the immediate results of renal biopsy and the importance of a blood reflow in the renal artery are the principal criteria during surgery, but must be discussed because there are no definitive criteria. Renal revascularization shall be proposed when totally occluded renal artery is associated with renal insufficiency and/or hypertension, especially when the other side can be affected by the same disease.