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Optical microendoscopy enabled by a microelectromechanical system (MEMS) scanning mirror offers great potential for in vivo diagnosis of early cancer inside the human body. However, an additional beam folding mirror is needed for a MEMS mirror to perform forward-view scanning, which drastically increases the diameter of the resultant MEMS endoscopic probe. This paper presents a new monolithic two-axis forward-view optical scanner that is composed of an electrothermally driven MEMS mirror and a beam folding mirror both vertically standing and integrated on a silicon substrate. The mirror plates of the two mirrors are parallel to each other with a small distance of 0.6 mm. The laser beam can be incident first on the MEMS mirror and then on the beam folding mirror, both at 45°. The MEMS scanner has been successfully fabricated. The measured optical scan angles of the MEMS mirror were 10.3° for the x axis and 10.2° for the y axis operated under only 3 V. The measured tip-tilt resonant frequencies of the MEMS mirror were 1590 Hz and 1850 Hz, respectively. With this compact MEMS design, a forward-view scanning endoscopic probe with an outer diameter as small as 2.5 mm can be made, which will enable such imaging probes to enter the subsegmental bronchi of an adult patient.

Background: Donor-derived Strongyloides stercoralis infection in solid organ transplant (SOT) recipients is uncommon. Immunosuppressed SOT recipients are at risk of developing severe forms of strongyloidiasis infection through transmission from an infected donor allograft., Methods: PubMed was searched for English-written articles published up to April 2015. Articles that reported cases of donor-derived strongyloidiasis infection in SOT recipients were reviewed for a pooled analysis., Results: A total of 27 cases were identified from various SOT recipients. Donors were mostly from Strongyloides endemic regions (23 cases). No transplant recipients received prophylaxis against strongyloidiasis infection. Median age was 53 years. Median time of presenting symptoms after the solid organ transplantation was 72 days. The most common presenting symptoms were gastrointestinal (GI) symptoms (19 cases; 70.4%). Diagnosis of strongyloidiasis infection was mainly made by the confirmation of Strongyloides larvae or worm in GI samples (19 cases) and respiratory samples (14 cases). Donor-derived strongyloidiasis infection was evidenced by serology test results in 17 cases and epidemiological risk assessment analysis in 10 cases. Ivermectin was the most commonly used medication with use of a combination of iverrmectin and albendazole or thiabendazole in 15 cases. Death was noted in 9 cases (34.6%) of 26 cases with known outcomes. Presence of sepsis or bacteremia was a predictor of mortality because it was seen in 9 patients who died (100.0%) and in 4 patients who survived (23.5%; P < .001)., Conclusions: Donor-derived strongyloidiasis infection in SOT recipients has high mortality. Effective donor screening and prophylaxis in high-risk SOT recipients may help to decrease morbidity and mortality associated with donor-derived strongyloidiasis., (Copyright © 2016 Elsevier Inc. All rights reserved.)

A facile, cost-effective, and manufacturable method to produce gold-polymer nanocomposite plasmonic nanorod arrays in high-aspect-ratio nanoporous alumina templates is reported, where the formation of gold nanoparticles and the polymerization of a photosensitive polymer by ultraviolet light are simultaneously performed. Transverse mode coupling within a two-dimensional array of the nanocomposite rods results in a progression of resonant modes in the visible and infrared spectral regions when illuminated at normal incidence, a phenomenon previously observed in nanoarrays of solid gold rods in an alumina template. Finite element full-wave analysis in a three-dimensional computational domain confirms our hypothesis that nanoparticles, arranged in a columnar structure, will show a response similar to that of solid gold rods. These studies demonstrate a new simple method of plasmonic nanoarray fabrication, apparently obviating the need for a cumbersome electrochemical process to grow nanoarrays.

We report the clinical and MR manifestations of an 18 year-old girl with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome. Recurrent status epilepticus caused reversible cytotoxic edema on diffusion-weighted images (DWI). Initial and one month follow-up MR spectroscopy, after seizure control, showed some discrepancies in the ratio of metabolites. N-acetylaspartate (NAA) partially recovered (NAA/creatine (Cr) ratio: 1.27-->1.84). This was because of a normalization of decreased NAA due to cellular dysfunction as a result of status epilepticus. A low ratio of NAA/Cr due to abnormal mitochondria remained in the decreased state. Reversible NAA/Cr ratios in the acute lesion suggested that NAA reflects the neuronal function as well as the level of neuronal structural damage. The altered NAA/Cr ratio better correlated with the abnormal signal intensity area of T2-weighted images (T2WI) and DWI than the lactate (Lac)/Cr ratio. With conservative treatment with anti-epileptics not accompanied by coenzyme Q or sodium dichloroacetate, lactate persistently increased (Lac/Cr ratio: 1.01-->1.21) because of the continued production of lactate in cells with respiratory deficiency, which is the main pathology of MELAS.

Metals typically have very large nonlinear susceptibilities (~10(6) times larger than those of typical dielectrics), but because they are nearly opaque their nonlinear properties are effectively inaccessible. We demonstrate numerically that a multilayer metal-dielectric structure in which the metal is the dominant nonlinear [chi((3))] material can have much larger intensity-dependent changes in the complex amplitude of the transmitted beam than a bulk sample containing the same thickness of metal. For 80 nm of copper the magnitude of the nonlinear phase shift is predicted to be as much as 40 times larger for the layered copper-silica sample, and the transmission is also greatly increased. The effective nonlinear refractive-index coefficient n(2) of this composite material can be as large as (3+6iota)x10(-9) cm (2)/W , which is among the largest values for known, reasonably transmissive materials.