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In just 20 years of history, the field of optomechanics has achieved impressive progress, stepping into the quantum regime just 5 years ago. Such remarkable advance relies on the technological revolution of nano-optomechanical systems, whose sensitivity towards thermal decoherence is strongly limited due to their ultra-low mass. Here we report a hybrid approach pushing nano-optomechanics to even lower scales. The concept relies on synthesising an efficient optical scatterer at the tip of singly clamped carbon nanotube resonators. We demonstrate high signal-to-noise motion readout and record force sensitivity, two orders of magnitude below the state of the art. Our work opens the perspective to extend quantum experiments and applications at room temperature. [ABSTRACT FROM AUTHOR]

A rare congenital ectodermal disorder characterized by ichthyosis follicularis, alopecia and photophobia has been designated the acronym IFAP. An X-linked recessive mode of inheritance was initially proposed but a few recent reports in girls suggested genetic heterogeneity of this syndrome. We herein describe a 3-year-old girl with clinical and histological features typical of IFAP. In addition to the already known features of the syndrome the patient also developed bilateral cataract. Electron microscopy examination of the skin showed partial disruption of the intercellular bridges, spongiotic changes and decrease in the number and size of desmosomes supporting the notion that IFAP may be a cell-to-cell adhesion disorder. [ABSTRACT FROM AUTHOR]

The aim of this study was to describe the etiology, morbidity and hospitalization costs associated with acute diarrhea among hospitalized children in Greece. During 1999, 294 hospitalized children (median age 1 y) with acute diarrhea were prospectively studied. Bacterial and viral enteropathogens were detected in 100 (34%) and 37 (12.5%) patients, respectively; 17 (6%) patients had mixed infections. Isolated agents included Salmonella spp. (43 patients; 15%), rotavirus (32; 11%), Campylobacter spp. (26; 9%), enteropathogenic Escherichia coli (16; 5.5%), Shigella spp. (11; 4%), Aeromonas spp. (7; 2.5%), adenovirus (6; 2%), Yersinia enterocolitica (6; 2%), enterohemorrhagic Escherichia coli (2; 0.5%) and Giardia lamblia (1; 0.5%). Of the patients with bacterial infection, 70% were admitted between April and September 1999. A rotavirus-associated peak was noted in March. Patients with a bacterial infection were hospitalized for longer periods than those with viral infections. It is concluded that bacterial enteropathogens account for one-third of admissions due to acute diarrhea among children in Greece and are associated with significant hospitalization costs. Rotavirus is also a frequent cause of acute diarrhea necessitating hospitalization. [ABSTRACT FROM AUTHOR]

Presents a study of immunocompetent children from southern Greece who were diagnosed with visceral leishmaniasis. Information on visceral leishmaniasis; Evaluation of access to medical services by the patient; Obstacle to the use of liposomal amphotericin B.

By combining X-ray absorption fine structure and X-ray diffraction measurements with density functional and molecular dynamics simulations, we study the structure of a set of AgxBi1−xS2 nanoparticles, a materials system of considerable current interest for photovoltaics. An apparent contradiction between the evidence provided by X-ray absorption and diffraction measurements is solved by means of the simulations. We find that disorder in the cation sublattice induces strong local distortions, leading to the appearance of short Ag–S bonds, the overall lattice symmetry remaining close to hexagonal. [ABSTRACT FROM AUTHOR]

Defects play an important role in tailoring the optoelectronic properties of materials. Supported by density functional theory (DFT) calculations, herein it is demonstrated that sulphur vacancies are able to engineer sub‐band gap photoresponse in the short‐wave infrared range due to formation of in‐gap states in Bi2S3 single crystals. Sulfurization and subsequent refill of the vacancies result in faster response but limit the spectral range to the near infrared as determined by the bandgap of Bi2S3. A facile chemical treatment is then explored to accelerate the speed of sulphur deficient (SD)‐based detectors on the order of 10 ms without sacrificing its spectral coverage of the infrared, while holding a high specific detectivity (D*) close to 1015 Jones in the visible–near infrared range and 1012 Jones at 1.6 µm. This work also provides new insights into the role sulphur vacancies play in the electronic structure and, as a result, in sub‐bandgap photoresponse enabling ultrasensitive, fast, and broadband photodetectors. [ABSTRACT FROM AUTHOR]