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Habitat heterogeneity is thought to affect top-down control of herbivorous insects and contribute to population stability by providing a more attractive microhabitat for natural enemies, potentially leading to reduced population fluctuations. Identifying the parameters that contribute to habitat heterogeneity promoting top-down control of herbivorous insects by natural enemies could facilitate appropriate management decisions, resulting in a decreased risk of pest insect outbreaks because of a higher level of predation. In our study, we measured the top-down pressure exerted by small mammals on the cocoons of a notorious pest insect in pine forests, the European pine sawfly ( Neodiprion sertifer ), which is known to be regulated by small mammal predation. The forest stands used differed in heterogeneity measured in terms of differences in tree diversity and density, understory vegetation height, presence/absence, and density of dead wood. We found higher predation in more dense spots within forest stands. Further, the effect of dead wood on sawfly cocoon predation depended on the pine proportion in forest stands. The addition of dead wood in a manipulation experiment had a slight positive effect on cocoon predation, while dead wood removal caused a clear decrease in predation rate, and the decrease was more pronounced when the proportion of pine increased. Our results show that habitat heterogeneity affects predation by generalist predators on herbivorous insects. This knowledge could be applied to reduce the risk of insect outbreaks by applying management methods that increase heterogeneity in perennial systems such as forests and orchards, thus decreasing the levels of insect damage.

Alkyne cross-metathesis of molybdenum carbyne complex [TolC≡Mo(OCCH 3 (CF 3 ) 2 ) 3 ]·DME with 2 equiv of functional ynamines or ynamides yields the primary cross-metathesis product with high regioselectivity (>98%) along with a molybdenum metallacyclobutadiene complex. NMR and X-ray crystal structure analysis reveals that ynamides derived from 1-(phenylethynyl)pyrrolidin-2-one selectively cleave the propagating molybdenum species in the ring-opening alkyne metathesis polymerization (ROAMP) of ring-strained 3,8-dihexyloxy-5,6-dihydro-11,12-didehydrodibenzo[a,e][8]annulene and irreversibly deactivate the diamagnetic molybdenum metallacyclobutadiene complex through a multidentate chelate binding mode. The chain termination of living ROAMP with substituted ethynylpyrrolidin-2-ones selectively transfers a functional end-group to the polymer chain, giving access to telechelic polymers. This regioselective carbyne transfer strategy gives access to amphiphilic block copolymers through synthetic cascades of ROAMP followed by ring-opening polymerization of strained ε-caprolactone.

Regioselective carbyne-transfer reagents derived from (3,3,3-trifluoroprop-1-yn-1-yl)benzene give access to functionalized ring-opening alkyne metathesis polymerization (ROAMP) initiators [R-C 6 H 4 C≡Mo(OC(CH 3 )(CF 3 ) 2 ) 3 ] featuring electron-donating or -withdrawing substituents on the benzylidyne. Kinetic studies and linear free-energy relationships reveal that the initiation step of the ring-opening alkyne metathesis polymerization of 5,6,11,12-tetradehydrobenzo[a,e][8]annulene exhibits a moderate positive Hammett reaction constant (ρ = +0.36). ROAMP catalysts featuring electron-withdrawing benzylidynes not only selectively increase the rate of initiation (k i ) over the rate of propagation (k p ) but also prevent undesired intra- and intermolecular chain-transfer processes, giving access to linear poly-(o-phenylene ethynylene) with narrow molecular weight distribution. The regioselective carbyne transfer methodology and the detailed mechanistic insight enabled the design of a bifunctional ROAMP-reversible addition-fragmentation chain-transfer (RAFT) initiator complex. ROAMP followed by RAFT polymerization yields hybrid poly-(o-phenylene ethynylene)-block-poly-(methyl acrylate) block copolymers.

Purpose: To describe multimodal imaging findings in a patient with foveal red spot syndrome., Methods: We report a case of a 57-year-old man with foveal red spot syndrome. Multimodal imaging techniques, including fundus color and red-free photographs, fluorescence angiography (Topcon 50DX; Topcon, Tokyo, Japan), MultiColor scanning laser imaging, spectral domain optical coherence tomography (Spectralis; Heidelberg Engineering, Heidelberg, Germany), swept source optical coherence tomography (DRI OCT-1 Atlantis; Topcon, Tokyo, Japan), adaptive optics (RTX-1; Imagine Eyes, Orsay, France), and microperimetry (MP1 Microperimeter; Nidek Technologies, Padua, Italy), were performed to confirm the diagnosis and determine the anatomical abnormalities related to the disease., Results: Conventional clinical examination and imaging studies failed to explain the patient's visual dysfunction and this specific macular abnormality. Using advanced ophthalmic technologies, including MultiColor imaging, spectral domain optical coherence tomography with high-density acquisition, swept source optical coherence tomography, adaptive optics, and microperimetry, we identified the nature of the macular manifestation accounting for pathology of the foveal red spot syndrome and his visual dysfunction., Conclusion: When conventional clinical examination and imaging techniques fail to identify the presence of and visual symptoms in foveal red spot syndrome, advanced technologies may be used to confirm the diagnosis and explain the etiology of the abnormality.

Background: In recent years the "tension-free" techniques have been progressively replacing conventional hernioplasty by Bassini and Shouldice. Personal experience in the application of various techniques using a prosthesis to make the back wall of the inguinal canal stronger is described., Methods: From January 1995 to February 1996, 119 non-selected patients were examined; they were operated by Trabucco's (100 cases), Lichtenstein's (16 cases), Gilbert's (13 cases) and Rives's (1 case) techniques, using polypropylene prostheses. Patients were followed for ten months (range 4-18) after surgery with Day-hospital checks at 1 month, 4 months, 1 year and 18 months., Results: Mortality was not observed. Morbility presented in 12 cases: 2 suppurating wounds, 3 seromas, 2 hematomas, 2 temporary neuralgias of the genito-femoral nerve and 2 scrotal edemas. There was a recurrence (0.8%)., Conclusions: The cases presented confirm the validity of the "tension-free" techniques, both for reduced incidence of complications and recurrences, and for a better compliance of the patient, compared with conventional techniques.