n-type Ge/Si antennas for THz sensing.

Ge-on-Si plasmonics holds the promise for compact and low-cost solutions in the manipulation of THz radiation. We discuss here the plasmonic properties of doped Ge bow-tie antennas made with a low-point cost CMOS mainstream technology. These antennas display resonances between 500 and 700 GHz, probed by THz time domain spectroscopy. We show surface functionalization of the antennas with a thin layer of α-lipoic acid that red-shifts the antenna resonances by about 20 GHz. Moreover, we show that antennas protected with a silicon nitride cap layer exhibit a comparable red-shift when covered with the biolayer. This suggests that the electromagnetic fields at the hotspot extend well beyond the cap layer, enabling the possibility to use the antennas with an improved protection of the plasmonic material in conjunction with microfluidics.

Influence of aqueous humor convection current on IOL opacification.

BACKGROUND AND PURPOSE: The opacification of Akreos Adapt (Bausch & Lomb, Rochester; NY) intraocular lens (IOL) has been previously reported in Literature. A metabolic change in aqueous humour was considered as the main trigger factor to IOL opacification. We report our case and discuss the association with Ex-PRESS, highlighting the particular pattern of IOL opacification and its possible relation with the intraocular convective motions of the aqueous. MATERIAL AND METHODS: We analyzed our case using both digital slit lamp acquisition and OCT Visante (Zeiss, Germany) images. A literature review was conducted to evaluate our results with that previously reported. CONCLUSION: The role of a relative stationary flow was reported as suggested concurrent mechanism in IOL opacification phenomenon.

Silicon photonic waveguide metrology using Mach-Zehnder interferometers.

We propose a procedure for characterizing fabrication deviations within a chip and among different chips in a wafer in silicon photonics technology. In particular, independent measurements of SOI thickness and waveguide width deviations can be mapped through the wafer, allowing a precise and non-destructive characterization of how these variations are distributed along the surface of the wafer. These deviations are critical for most wavelength-dependent integrated devices, like microring resonators, filters, etc. We also show that the technique allows for the characterization of proximity effects.

Modeling of strain-induced Pockels effect in Silicon.

We propose a theoretical model to describe the strain-induced linear electro-optic (Pockels) effect in centro-symmetric crystals. The general formulation is presented and the specific case of the strained silicon is investigated in detail because of its attractive properties for integrated optics. The outcome of this analysis is a linear relation between the second order susceptibility tensor and the strain gradient tensor, depending generically on fifteen coefficients. The proposed model greatly simplifies the description of the electro-optic effect in strained silicon waveguides, providing a powerful and effective tool for design and optimization of optical devices.

Systemic complications of esophageal lichen planus.

Lichen planus is an uncommon inflammatory mucocutaneous disorder affecting the skin and its appendages, as well as oral and genital mucosa. Involvement of the esophageal mucosa is rare and causes significant morbidity, with dysphagia and risk of long-term complications, such as esophageal strictures and stenosis. Esophageal lichen planus is an underreported condition in the spectrum of lichenoid tissue reactions, presenting the risk of systemic manifestations. We describe a patient with severe, long-standing esophageal lichen planus, which had led to marked weight-loss, malnutrition syndrome and chronic respiratory distress due to recurrent aspiration pneumonia. Diagnosis was confirmed by the presence of concomitant muco-cutaneous lesions and characteristic endoscopic and histological findings. Systemic therapy with cyclosporine A and micronutrient supplementation led to rapid clinical improvement. Early diagnosis of esophageal lichen planus as well as effective systemic immunosuppressive treatment is crucial in order to prevent short- and long-term complications.

Ophthalmological aspects of IBD.

Ocular manifestations occur in 4-12% of patients with IBD. Uveitis and iritis are more frequently associated with ulcerative colitis while episcleritis is more common in Crohn's disease. Some ocular manifestations in IBD can be secondary to treatment and/or effects of the intestinal disease itself. The specific management of ocular manifestations in IBD requires the use of topical steroids and FANS, cycloplegics, systemic steroids or immunosuppressive drugs. When conventional therapies fail to control the ocular manifestations in IBD, the new biologic drugs can be considered as good alternative treatments. Early diagnosis and effective treatment may avoid the onset of severe and sometimes persisting complications. In some cases, a surgical approach is required to treat eye complications, i.e. cataract, and to improve the patient's quality of life.

Plasma exchange for polyradiculoneuropathy following kidney transplantation: a case report.

We describe a case of polyradiculoneuropathy (PRN) following living donor kidney transplantation, without clinical evidence of preexisting infection. In this study plasma exchange treatment resulted 6 days later in improvement in extremity weakness and paresthesias in the upper and lower extremities. Total neurological recovery was obtained 3 months after the onset of symptoms.

Vestibular evaluation in Behçet's disease. Personal experience.

Few reports have appeared in the literature concerning vestibular findings in Behçet's disease. In the present study, extensive vestibular testing, performed in 14 patients (8 male, 6 female; mean age: 32 years; range: 12-51) presenting definite Behçet's disease, revealed a high prevalence of central vestibular dysfunctions (78%). Data reported here suggest that an otoneurological evaluation of Behçet's disease patients may be helpful in identifying unexpected vestibular dysfunctions and central nervous system involvement different from the classical manifestations of the neuro-Behçet's syndrome.

[Ultrasonic evaluation of early atherosclerotic damage in patients with type 1 diabetes mellitus]. / Valutazione ultrasonografica del danno aterosclerotico precoce in diabetici di tipo 1 insulino-dipendenti.

UNLABELLED: The aim of this study was to evaluate the influence of metabolic control on the development of atherosclerotic lesions in type 1 insulin-dependent diabetic patients (IDDM). MATERIALS AND METHODS: Twenty-eight well controlled IDDM patients, without known risk factors or clinical evidence of cardiovascular disease, together with 28 age-matched healthy controls spontaneously underwent high-resolution echographic evaluation of carotid femoral arteries. A global score of atherosclerotic damage as been assigned to the four investigated vessels on the basis of 1-6 scale, which takes into account most important ultrasound atherosclerotic lesion found in every artery. RESULTS: Diabetic and healthy controls differed significantly as regard to medio-intimal carotid thickness (p < 0.001), but were similar as for score of atherosclerotic damage. CONCLUSIONS: Our results suggest that, in spite of a carotid wall medio-intimal thickness more pronounced in IDDM patients, well controlled IDDM is associated with atherosclerotic damage almost identical to that of healthy age-matched controls.

Automated measurement of lactate dehydrogenase, alkaline phosphatase and gamma-glutamyltransferase in urines: an alternative to the manual procedure.

A sensitive and precise automated assay of urinary lactate dehydrogenase (EC 1.1.1.27), alkaline phosphatase (EC 3.1.3.1) and gamma-glutamyltransferase (EC 2.3.2.2) is described. For this purpose, we used a BM/Hitachi System 704 model and reagents for automated analysis of serum enzymes from Boehringer Mannheim. However, the schedules of enzyme chemistry parameters recorded by the autoanalyzer and the spectrophotometric calibration are reprogrammed to meet requirements deriving from urine adoption and to optimize the enzyme assay in this unusual medium.

More on effects of storage time and temperature on urinary enzymes: a 1-year study.

Results of our conclusive study on urinary enzyme stability during sample storage are reported. We measured alanine aminopeptidase (AAP) and N-acetyl-beta-D-glucosaminidase (NAG) in morning urines from 9 healthy normal subjects immediately after collection and throughout a 1-year storage at -70 and -20 degrees C. AAP proved to be quite stable at -70 degrees C (99.2% of the basal value at the end of the year). NAG is partially preserved (84.1% of the basal value) at -70 degrees C, but significantly decreased (50.4%) at -20 degrees C.

Urinary cholinesterase activity is increased in insulin-dependent diabetics: further evidence of diabetic tubular dysfunction.

We measured the cholinesterase activity in morning urines from 63 insulin-dependent diabetics and 27 controls. The total esterase (TotE) activity (Ellman's method) has been divided into aliesterase (AliE), pseudocholinesterase and acetylcholinesterase by means of two inhibitors, eserine and quinidine. Diabetics were divided in 2 groups according to the urinary albumin/creatinine ratio (mg/mmol, < 2 in group 1, > 2 in group 2). The urinary cholinesterase behavior was correlated with that of a known tubular lysosomal hydrolase, N-acetyl-beta-D-glucosaminidase (NAG). Compared to normals, in addition to a significant increase in urinary NAG in diabetes (in group 2 more than in group 1), TotE and AliE were also significantly raised (+36% and 109% of the controls, in group 1 as much as in group 2).