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1$T$-TaSe$_2$ is widely believed to host a Mott metal-insulator transition in the charge density wave (CDW) phase according to the spectroscopic observation of a band gap that extends across all momentum space. Previous investigations inferred that the occurrence of the Mott phase is limited to the surface only of bulk specimens, but recent analysis on thin samples revealed that the Mott-like behavior, observed in the monolayer, is rapidly suppressed with increasing thickness. Here, we report combined time- and angle-resolved photoemission spectroscopy and theoretical investigations of the electronic structure of 1$T$-TaSe$_2$. Our experimental results confirm the existence of a state above $E_F$, previously ascribed to the upper Hubbard band, and an overall band gap of $\sim 0.7$ eV at $\overline{\Gamma}$. However, supported by density functional theory calculations, we demonstrate that the origin of this state and the gap rests on band structure modifications induced by the CDW phase alone, without the need for Mott correlation effects., Comment: Accepted by PRL

By exciting with sub-10-fs 1.6-μm pulses the quasi-one-dimensional Mott insulator ETF2TCNQ, we observe prompt collapse of the Mott gap modulated by 24-THz oscillations of the gap, which are assigned to quantum interference between holon-doublon excitations. © 2010 Optical Society of America.

IgA nephropathy (IgAN) is the most common glomerulonephritis worldwide, but its etiologic mechanisms are still poorly understood. Different prevalences among ethnic groups and familial aggregation, together with an increased familial risk, suggest important genetic influences on its pathogenesis. A locus for familial IgAN, called "IGAN1," on chromosome 6q22-23 has been described, without the identification of any responsible gene. The partners of the European IgAN Consortium organized a second genomewide scan in 22 new informative Italian multiplex families. A total of 186 subjects (59 affected and 127 unaffected) were genotyped and were included in a two-stage genomewide linkage analysis. The regions 4q26-31 and 17q12-22 exhibited the strongest evidence of linkage by nonparametric analysis (best P=.0025 and .0045, respectively). These localizations were also supported by multipoint parametric analysis, in which peak LOD scores of 1.83 ( alpha =0.50) and 2.56 ( alpha =0.65) were obtained using the affected-only dominant model, and by allowance for the presence of genetic heterogeneity. Our results provide further evidence for genetic heterogeneity among families with IgAN. Evidence of linkage to multiple chromosomal regions is consistent with both an oligo/polygenic and a multiple-susceptibility-gene model for familial IgAN, with small or moderate effects in determining the pathological phenotype. Although we identified new candidate regions, replication studies are required to confirm the genetic contribution to familial IgAN.

Femtosecond lasers enable the fabrication of both optical waveguides and buried microfluidic channels on a glass substrate. The waveguides are used to integrate optical detection in a commercial microfluidic lab-on-chip for capillary electrophoresis.

This paper describes results obtained with a lab-on-a-chip with monolithically integrated optical waveguides. The waveguides are written with femtosecond laser pulses, enabling one to define location and dimensions of very confined detection windows along a microfluidic channel. The present results demonstrate the monitoring of plug passage of fluorescently labelled DNA molecules, during the process of microchip capillary electrophoresis.

Mayer-Rokitansky-Küster-Hauser syndrome (MRKH syndrome) is characterized by Müllerian duct structures agenesis: the vagina atresia is the commonest variant. There can be some anomalies associated, such as renal, skeletal, spine malformations and others. Patients with MRKH can show different presentation from newborn period to adolescence. We report our experience in treatment of the vaginal atresia presenting in two young girls as a sign of MRKH syndrome.

The substitution of conventional bench-top instrumentation by fully integrated lab-on-chip systems continues to be a challenge. The integration of microfluidics and integrated optics in glass is an important step towards this goal, forming the focus of this work [1]. In particular, excitation and detection of fluorescence emitted by labeled biomolecules flowing through a microfluidic channel is considered. Excitation occurs at specific wavelengths by means of waveguides inscribed with femtosecond laser pulses in a commercial, glass lab-on-chip. A widely known diagnostic application that will exploit this sensing scheme is the monitoring of microchip capillary electrophoresis (MCE) leading to separation of DNA fragments of different lengths, labeled with fluorescent dye molecules. In order to meet the resolution demands of MCE separation and to achieve multi-point sensing, we envision a device consisting of on-chip integrated optical splitters written coplanar with the microfluidic channel along which MCE separation takes place.

Liposarcomas represent the single most common type of soft tissue sarcoma. Its abdominal localization is rare, occurring in only 5% of cases. A 55 year old male was found to have a case of primary giant liposarcoma of the mesenterium with a maximum diameter of 40 cm and weight of 9 kg. Computed tomography revealed the presence of a large mass presenting a dishomogeneous density with an adipose component, probably of mesenteric origin. A xifopubic laparotomy confirmed the presence of a pedunculated growth originating from the mesentery. The mass was removed and the histopathological report noted a well differentiated sclerosing liposarcoma with the peritoneal liquid positive for malignant cells. Surgery currently represents the only possibly curative therapy for this type of tumour but close long-term follow up and accurate evaluation of the clinicopathologic parameters are needed.

Optical waveguides have been fabricated focusing femtosecond laser pulses into a commercial microfluidic chip. The waveguides intersect the channels and are used to optically excite their content. Fluorescence from the optically addressed volume is efficiently collected by a fiber, resulting in an highly compact and portable setup.

Fluorescence detection is known to be one of the most sensitive among the different optical sensing techniques. This work focuses on excitation and detection of fluorescence emitted by DNA strands labeled with fluorescent dye molecules that can be excited at a specific wavelength. Excitation occurs via optical channel waveguides written with femtosecond laser pulses applied coplanar with a microfluidic channel on a glass chip. The waveguides are optically characterized in order to facilitate the design of sensing structures which can be applied for monitoring the spatial separation of biochemical species as a result of capillary electrophoresis.

Femtosecond electric-field assisted pump-probe measurements are a new approach to the study of fundamental processes within organic optoelectronic devices. Here we report a detailed study of organic light-emitting diodes based on poly (9,9-dioctylfluorene), using both temporal and spectral information to investigate polaron generation, due to field induced singlet dissociation, and their subsequent recombination. The fundamental event in electroluminescence is time resolved: we find that initially free polarons coalesce into intermediate pairs of both singlets and triplets multiplicity which subsequently decay into the neutral state. Our results indicate that the efficiency of singlet formation, b ¡Ö 0.7, is much higher than expected from simple state degeneracy arguments (b = 0.25).

IgA nephropathy (IgAN) is a common form of primary glomerulonephritis characterized by diffuse glomerular mesangial IgA1 deposition that leads to mesangial proliferation and chronic glomerular inflammation. Analyses of serum IgA1 from IgAN patients revealed an abnormal galactosylation of the O-linked carbohydrate moieties of IgA that may be a result of altered activity of core 1 beta1,3-galactosyltransferase (C1GalT1). To evaluate the association between C1GalT1 single nucleotide polymorphisms (SNPs) and IgAN, we performed a case control study on cohorts from the Italian population.We sequenced C1GalT1 coding and promoter regions in 284 IgAN patients and 210 healthy controls. The functional role of 3' untranslated region (3'UTR) SNPs was studied using electrophoretic mobility shift assays and real-time quantitative PCR.We analyzed 8 SNPs in the C1GalT1 gene: 5 SNPs were in the promoter region and 3 SNPs in the 3'UTR. The allele 1365G in the 3'UTR was significantly more frequent in IgAN patients than in healthy controls.The 1365G allele and 1365G/G genotype seem to confer susceptibility to IgAN.