Unexpected silicon localization in calcium carbonate exoskeleton of cultured and fossil coccolithophores.

Coccolithophores, marine calcifying phytoplankton, are important primary producers impacting the global carbon cycle at different timescales. Their biomineral structures, the calcite containing coccoliths, are among the most elaborate hard parts of any organism. Understanding the morphogenesis of coccoliths is not only relevant in the context of coccolithophore eco-physiology but will also inform biomineralization and crystal design research more generally. The recent discovery of a silicon (Si) requirement for crystal shaping in some coccolithophores has opened up a new avenue of biomineralization research. In order to develop a mechanistic understanding of the role of Si, the presence and localization of this chemical element in coccoliths needs to be known. Here, we document for the first time the uneven Si distribution in Helicosphaera carteri coccoliths through three synchrotron-based techniques employing X-ray Fluorescence and Infrared Spectromicroscopy. The enrichment of Si in specific areas of the coccoliths point to a targeted role of this element in the coccolith formation. Our findings mark a key step in biomineralization research because it opens the door for a detailed mechanistic understanding of the role Si plays in shaping coccolith crystals.

An integrated ultra-high vacuum apparatus for growth and in situ characterization of complex materials.

Here, we present an integrated ultra-high vacuum apparatus-named MBE-Cluster -dedicated to the growth and in situ structural, spectroscopic, and magnetic characterization of complex materials. Molecular Beam Epitaxy (MBE) growth of metal oxides, e.g., manganites, and deposition of the patterned metallic layers can be fabricated and in situ characterized by reflection high-energy electron diffraction, low-energy electron diffraction, Auger electron spectroscopy, x-ray photoemission spectroscopy, and azimuthal longitudinal magneto-optic Kerr effect. The temperature can be controlled in the range from 5 K to 580 K, with the possibility of application of magnetic fields H up to ±7 kOe and electric fields E for voltages up to ±500 V. The MBE-Cluster operates for in-house research as well as user facility in combination with the APE beamlines at Sincrotrone-Trieste and the high harmonic generator facility for time-resolved spectroscopy.

High prevalence of autoimmune diseases in women with endometriosis: a case-control study.

The immune system seems to be involved in the pathogenesis of endometriosis. Peritoneal chronic inflammation is present and natural killer cells and macrophages abnormalities have been reported in women with the disease. Moreover, a higher production of serum autoantibodies has been found, which could be related to various factors; some still need to be clarified. The correlation between endometriosis and autoimmune diseases is still unclear with few and conflicting available data. The aim of this study was to evaluate the prevalence of autoimmune diseases, as conditions with a possible common pathogenetic factor, in women affected by endometriosis, in order to address future research on its pathogenesis. This retrospective case-control study includes one hundred and forty-eight women with endometriosis and 150 controls. All women were aged between 18 and 45. Informed consent was obtained from all participants of the study. Considered autoimmune diseases include systemic lupus erythematosus (SLE), celiac disease (CD), inflammatory bowel disease (IBD), and autoimmune thyroiditis. Statistical comparison of patients and control group was performed by means of chi-square test or Fisher's exact test as appropriate. Statistical comparison of parametric variable (age) among the groups was performed by t-test for unpaired data. Age was expressed as mean. A value of .05 or less was considered as significant. In the case group, five patients were affected by IBD, while the disease was not observed in the control group (p = .07). SLE was found in eight patients in the case group, while only one was found in the control group (p = .01). Fifteen women in the case group were affected by CD, while the disease was present only in one woman in the control group (p<.0001). A significant correlation was also found between endometriosis and autoimmune thyroiditis: 80 patients with endometriosis had thyroid diseases versus 14 patients in the control group (p<.0001). Our study reports an association between endometriosis and autoimmune disorders, showing a higher prevalence of autoimmune diseases in women affected by endometriosis. These results support a possible autoimmune pathogenesis of endometriosis.

Endometriosis: seeking optimal management in women approaching menopause.

The incidence of endometriosis in middle-aged women is not minimal compared to that in the reproductive age group. The treatment of affected women after childbearing age to the natural transition toward menopause has received considerably poor attention. Disease management is problematic for these women due to increased contraindications regarding hormonal treatment and the possibility for malignant transformation, considering the increased cancer risk in patients with a long-standing history of the disease. This state-of-the-art review aims for the first time to assess the benefits of the available therapies to help guide treatment decisions for the care of endometriosis in women approaching menopause. Progestins are proven effective in reducing pain and should be preferred in these women. According to the international guidelines that lack precise recommendations, hysterectomy with bilateral salpingo-oophorectomy should be the definitive therapy in women who have completed their reproductive arc, if medical therapy has failed. Strict surveillance or surgery with removal of affected gonads should be considered in cases of long-standing or recurrent endometriomas, especially in the presence of modifications of ultrasonographic cyst patterns. Although rare, malignant transformation of various tissues in endometriosis patients has been described, and management is herein discussed.

MOKE setup exploiting a nematic liquid crystal modulator.

Here we report on the magneto-optical Kerr effect employing a nematic liquid crystal (LC) device as an optical modulator. This device allows performing intensity, phase, and polarization modulated measurements with a huge signal-to-noise ratio when compared to those obtained by means of an opto-mechanical chopper and a photo-elastic modulator. The results demonstrate that the optimal performance is achieved modulating the polarization state of the incident light by means of the LCs.

A reaction cell for ambient pressure soft x-ray absorption spectroscopy.

We present a new experimental setup for performing X-ray Absorption Spectroscopy (XAS) in the soft X-ray range at ambient pressure. The ambient pressure XAS setup is fully compatible with the ultra high vacuum environment of a synchrotron radiation spectroscopy beamline end station by means of ultrathin Si3N4 membranes acting as windows for the X-ray beam and seal of the atmospheric sample environment. The XAS detection is performed in total electron yield (TEY) mode by probing the drain current from the sample with a picoammeter. The high signal/noise ratio achievable in the TEY mode, combined with a continuous scanning of the X-ray energies, makes it possible recording XAS spectra in a few seconds. The first results show the performance of this setup to record fast XAS spectra from sample surfaces exposed at atmospheric pressure, even in the case of highly insulating samples. The use of a permanent magnet inside the reaction cell enables the measurement of X-ray magnetic circular dichroism at ambient pressure.