Development of a 3D ultrafast laser written near-infrared spectro-interferometer.

Direct ultrafast laser photoinscription of transparent materials is a powerful technique for the development of embedded 3D photonics. This is particularly adaptable for astrophotonic devices when a number of inputs are required. The process relies essentially on volume fabrication of waveguiding structures in flexible 3D designs and refractive index contrast parameters adjustable for specific spectral ranges. This enables 3D geometry and thus avoids in-plane crossings of waveguides that can induce losses and cross talk in multi-telescope beam combiners. The additional novel capability of the technique allows for the fabrication of high aspect ratio nanostructures nonperturbatively sampling the optical field. Combining ultrafast laser micro- and nanoprocessing with engineered beams, we present here results for the development of chip-sized silica glass integrated robust 3D three-telescope beam combiners in the near-IR range, as well as embedded diffraction gratings, for phase closure analysis and spectro-interferometry applications in astronomy.

Sarcoma del estroma endometrial mixoide, una rara variante histopatológica. Dos casos clinicopatológicos / Myxoid endometrial stromal sarcoma: A rare histopathologic variant. Two clinicopathological cases

La variante mixoide del sarcoma del estroma endometrial es una neoplasia uterina extremadamente rara caracterizada por la presencia de predominante material mixoide y células fusiformes atípicas que muestran características histopatológicas e inmunohistoquímicas de sarcoma del estroma endometrial. Presentamos 2 casos clinicopatológicos de mujeres de 54 y 76 años de edad, ambas con metrorragia posmenopáusica, útero aumentado de tamaño e imagen de tumoración dependiente de la pared miometrial, sometidas a histerectomía total con doble anexectomía con diagnóstico anatomopatológico de sarcoma del estroma endometrial variante mixoide

Myxoid endometrial stromal sarcoma is an extremely rare uterine neoplasm characterised by the presence of atypical predominantly myxoid material fusiform cells showing histopathological and immunohistochemical characteristics of endometrial stromal sarcoma. We present two clinicopathological cases of a 54-year-old woman and 76-year-old woman, both with postmenopausal vaginal bleeding, enlarged uterus and myometrial wall-dependent tumour imaging, undergoing total hysterectomy with double oophorectomy with pathological diagnosis of myxoid endometrial stromal sarcoma

Laser-induced breakdown spectroscopy (LIBS) analysis of laser processing in active crystal with nanosecond laser pulses.

Laser-induced breakdown spectroscopy (LIBS) analysis is applied to study the ablation threshold and the main plasma features of active crystals used for laser processing with Nd(3+) ions. The experiments were conducted by using nanosecond laser pulses from a neodymium-doped yttrium aluminum garnet (Nd : YAG) laser and its harmonics. In particular, we have studied the ablation process in SBN, strontium barium niobate (SrxBa1-xNb2O6, x = 0.6), and SBN, sodium barium niobate (Ba2NaNb5O15), nonlinear and ferroelectric crystals. Two different ablation regimes have been identified by LIBS analysis with high sensitivity compared with the standard method of hole-diameter measurement. Analyzing spectroscopically the plasma emission, we have found a particular behavior with the excitation wavelength. For example, the electronic density and temperature in SBN-generated plasmas present an abnormal behavior with the excitation wavelength. We therefore conclude that the energy gap corresponding to these crystals plays an important role in describing this fact. Hence, the resonant ablation in doped crystals can be a suitable point for exploration in further works in order to use the plasma performances to optimize the laser processing by nanosecond pulses for technological applications.

Direct laser writing of near-IR step-index buried channel waveguides in rare earth doped YAG.

A new (to our knowledge) ultrashort laser pulse irradiation regime that allows us to directly modify and increase the refractive index of rare earth doped YAG polycrystalline ceramics has been identified. Single-mode buried channel waveguides in both Ho:YAG and Er:YAG ceramics at the near-IR wavelengths of 1.55 µm and 1.95 µm are demonstrated by fabricating positive square step-index cores. Minimum propagation losses of 1.5 dB cm(-1) at a 1.51 µm wavelength have been preliminarily obtained. Confocal microluminescence mapping reveals that the increased refractive index regions retain the near-IR spectral properties of Er3+ ions in the YAG crystalline matrix.

Microstructuring of Nd:YAG crystals by proton-beam writing.

We report on the microstructuring of Nd:YAG crystals by direct proton-beam writing. Buried channel waveguides have been fabricated with full spatial control by the combined variation of crystal position and proton energy. The fluorescence images of the obtained structures have been used to evaluate the potential application of the fabricated structures for laser gain as well as to elucidate the mechanism at the basis of the refractive index increment induced at the end of the proton path. We have concluded that this increment is very likely a local enhancement in the electronic polarizability caused by nuclear collisions.

Partial purification, characterisation and histochemical localisation of alkaline phosphatase from ascocarps of the edible desert truffle Terfezia claveryi Chatin.

In the present paper, we confirmed that alkaline phosphatase (ALP) is the main phosphatase present in ascocarps of the edible mycorrhizal fungus Terfezia claveryi. The enzyme was partially purified by precipitation with polyethylene glycol. The purification achieved from a crude extract was fivefold, with 53% of the activity recovered, and acid phosphatase, most of the lipids and phenolic compounds were eliminated. Alkaline phosphatase was kinetically characterised at pH 10.0, the optimum for this enzyme, using p-nitrophenyl phosphate as substrate. The V(max) and K(m) values were 0.3 micromol.min(-1).mg(-1) protein and 9.0 mM, respectively. Orthovanadate was a competitive inhibitor of ALP, with a K(i) of 42.5 microM. The enzyme was histochemically localised in the peridium, the hypothecium and in the ascogenic hyphae of the gleba using both colour and fluorescent reactions. The results presented suggest that the ascocarp of T. claveryi, at some stages of its development, may become nutritionally autonomous and independent of the host plant.

field optical and micro-luminescence investigations of femtosecond laser micro-structured Nd:YAG crystals.

We report on the in-depth micro-modifications induced by femtosecond laser ablation in Nd:YAG crystals. Near Field Optical experiments have revealed that, below the ablated volume, a permanent change in the Nd:YAG reflectivity, extending parallel to the irradiation direction, has been induced. Micro-luminescence experiments have provided experimental evidence that these permanent changes in the surface reflectivity are accompanied by strong changes in the luminescence properties of Nd(3+) ions revealing relevant micro structural modifications in the Nd:YAG system.

Expression of Bcl-2 protein in human laryngeal keratoses.

Strong Bcl-2 immunostaining was detected in 2 of 21 samples of human laryngeal keratoses, one of which contained neither p53 gene mutation nor human papillomavirus sequences nor significant levels of p53 protein. The other 19 samples including 6 cases with moderate or strong p53 staining were Bcl-2-unreactive or had minimal Bcl-2 reactivity similar to that observed in normal samples. Minimal Bcl-2 staining in 5 samples with moderate or severe dysplasia was only seen in the adjacent nondysplastic area. Our study shows that (1) some laryngeal keratoses strongly express Bcl-2 protein, (2) Bcl-2 expression does not appear to be dependent on p53, and (3) moderate or severe dysplasias may occur despite a decline in Bcl-2 expression.