Pyroxene and olivine chemistry as an indicator of melt evolution. A contribution to the understanding of Somma-Vesuvius eruptive behaviour

Explosive volcanism is commonly related to a process known as fragmentation of magma containing bubbles rich in gas phases. This process is activated by the brittle failure of the melt as its strength is overcame by viscous stresses related to bubble growth and ascending magma flow. Individual volcanoes often produce alternating effusive and explosive eruptions which cyclical dynamics remain unclear and are a subject of ongoing debate. The Somma-Vesuvius, famous for its explosive Pompeii eruption in AD 79, generated a wide variety of eruptive events during the past 33 Ky, ranging from mild effusive (inter-Plinian) eruptions to highly disruptive (Plinian) phenomena. Over the last 3 decades, a large number of samples have been collected from the Somma-Vesuvius volcanic complex. As a result of this research effort, a large database of chemical analyses of various volcanic products from lavas to pumices and tephra is currently available. This allowed for detailed studies of magma compositions aimed at reconstructing magma differentiation processes and identifying parental and primary magma compositions. Currently there is no general consensus on whether the primary magma precursors to both eruption styles were of a similar composition. At the same time, the compositions of mineral phases in Somma-Vesuvius volcanic products have received significantly less attention. Phenocrysts phases such as olivine and clinopyroxene occur early on the liquid line of descent and dominate fractional crystallization in the primitive magmas. At the later stages of crystallisation they are joined and/or replaced by feldspars, feldspathoids, biotite and oxides. This project aims at characterising minor and trace elements in both olivine and clinopyroxene phenocrysts from representative lava, scoriae and pumice samples from the main Plinian eruptions and a range of inter-Plinian events over the last 33 Ky. The main aim of this work is to present new constraints on the factors leading to the different Somma-Vesuvius eruptive styles. In order to achieve this goal, 14 pumice samples from Plinian pyroclastic deposits as well as 3 scoriae and 8 lava samples from effusive flows were collected, and a representative number of olivine and clinopyroxene phenocrysts were selected under an optical microscope from each sample and analysed with an electronic microprobe and by a LA-ICP mass-spectrometry, resulting in a large database containing 2127 EMP and 1259 LA-ICP-MS analyses. The mineral compositions obtained were examined considering the following two factors: 1) eruptive style; and 2) age of the samples. Magmas from Plinian and inter-Plinian eruptions were compared using the results of this study in conjunction with published data on lava chemistry and the compositions of melt and fluid inclusions in phenocrysts. Further, the mineral compositions have been compared with those from other volcanoes of the Roman Comagmatic Province (RCP) and also from other tectonic settings such as Oceanic Islands, Volcanic Rifts, Mid-ocean Ridges and Supra-subduction Zones, in order to assess the extent of compositional variation among Somma-Vesuvius olivine and pyroxene phenocrysts. The above approach led to the following main conclusions: I) olivine and clinopyroxene phenocrysts crystallized simultaneously over a large temperature range from the earliest stages of melt evolution; II) both olivines and clinopyroxenes display clear bimodal distribution in terms of the proportions between the Mg-rich and Fe-rich end members (Mg# = Mg/(Mg+Fe)): the primitive group has compositions Mg#92-82, whereas the evolved group has compositions Mg#82-72; III) both Plinian and inter-Plinian clinopyroxenes and olivines populations exhibit a narrow trend of major, minor and trace elements contents as a function of their Mg#, when compared with mineral compositions from other tectonic settings, including the RCP, indicating a narrow range of melt compositions within the Somma-Vesuvius plumbing system for a given stage of differentiation regardless of the eruption style; IV) clinopyroxene and olivine phenocrysts compositions in inter-Plinian eruption products display a narrower range compared to the Plinian eruptions; V) as the result of a narrow compositional range of phenocrysts in inter-Plinian eruptions, there is a larger difference in phenocryst populations composition between individual inter-Plinian eruptions than between Plinian eruptions; VI) The more evolved (Mg#82-72) Plinian and inter-Plinian clinopyroxene phenocrysts in rocks younger than 2.8 Ky show clear Ca enrichment (23.5-24.5 wt % CaO) in respect to the older rocks. Some of the more primitive olivine phenocrysts (Fo#92-82) from the inter-Plinian eruptions younger than AD 472 (CaO 0.30-0.45 wt %) are also more enriched in Ca than older olivine phenocrysts; VII) Overall, the compositions of clinopyroxenes from the inter-Plinian eruptions display REE contents which are within the range of the Plinian clinopyroxenes. The above results suggest: I) a prevalently magmatic origin of olivine phenocrysts whose presence was previously mainly ascribed to magma reaction with the carbonate basement of the Campania Plain; II) Persisting multiple sites of crystallisation where magmas of variable extent of fractionation reside at any given time regardless of the type of eruptive activity; III) Chemically similar sources of parental magmas feeding the Somma-Vesuvius system, which does not appear to have changed over the last 33 Ky; and IV) A common composition of parental magmas for the Plinian and inter-Plinian eruptions of the Somma-Vesuvius. Therefore, this study suggests that the magma residence times and the magma supply rate are the likely main factors controlling eruption style at Somma-Vesuvius. Further insights into these processes may be derived from the study of melt and fluid inclusions within the Somma-Vesuvius olivine and clinopyroxene phenocrysts, which is envisaged as a continuation to this project

Invited response on: dual-plane retro-pectoral versus pre-pectoral dti breast reconstruction. An italian multicenter experience

Invited Response on: Dual-Plane Retro-Pectoral Versus Pre-pectoral DTI Breast Reconstruction: An Italian Multicenter Experienc

The NOBOX protein becomes undetectable in developmentally competent antral and ovulated oocytes

The oocyte-specific NOBOX protein is an important player during oocyte growth. Its absence in Nobox-/- mice arrests the transition from primordial to growing follicles and down-regulates the expression of a number of genes, including Oct4, a transcription factor crucial in the acquisition of oocyte developmental competence. Despite its role during folliculogenesis, a clear description of the expression of NOBOX throughout oocyte growth is lacking. Here, we have analysed the pattern of expression of both the Nobox gene (qRT-PCR) and its protein (immunofluorescence) during folliculogenesis, classifying the oocytes based on their size (six classes: 10-30, 31-40, 41-50, 51-60, 61-70, 71-80 mm) and chromatin organisation (NSN, Non Surrounded Nucleolus or SN, Surrounded Nucleolus). Significant differences were observed in Nobox transcription in the group of 41-50 mm (NSN > SN), 71-80 mm (NSN > SN) and in developmentally incompetent metaphase II-derived NSN (MIINSN) or competent metaphase II-derived SN (MIISN) oocytes (MIINSN > MIISN). The NOBOX protein is expressed throughout oocyte growth in the nucleus of ovarian NSN and in MIINSN oocytes; in contrast, beginning with SN oocytes of 61-70 mm, it becomes almost undetectable. Our data, while being in line with the hypothesis of a regulative role of NOBOX on Oct4 gene expression at the primordial/primary stage, when both transcription factors are coincidentally expressed, also indicate that this role might not be maintained in the subsequent growing stages. Furthermore, the sharp difference of NOBOX expression in developmentally incompetent or competent oocytes makes this protein a putative marker of their quality

Geophysics

Contains reports on four research projects

Feulgen-DNA Content and C-Banding of Robertsonian Transformed Karyotypes in Dugesia Lugubris

SUMMARYIn the planarian species, Dugesia lugubris, two biotypes are found: E (2n = 8, n = 4) and F (2n = 6, n = 3); on the basis of karyometric studies it has been hypothesized that the second was derived from the first through a Robert-sonian mechanism of centric fusion. The quantitative cytochemical data reported here confirm the hypothesis of karyotype evolution, since there are no significant differences between the DNA content of the nucleus in the two biotypes. The regenerative blastemas of both biotypes contain a number of cellular populations with a variable Feulgen-DNA content; these correspond to successive doublings of the 2C diploid content. In addition, metaphase plates with multistranded chromosomes have been found. A difference between the chromosome C-banding in the two biotypes has also been observed

Extended latissimus dorsi kite flap (eld-k flap). Revisiting an old place for a total autologous breast reconstruction in patients with medium to large breasts

Background: The latissimus dorsi (LD) flap represents one of the most reliable methods for autologous breast reconstruction. However, in many patients, the exclusive use of this technique may not guarantee the restoration of an adequate volume and projection. We report our experience with the extended latissimus dorsi kite flap (ELD-K flap), an alternative surgical approach to maximize the volume of the fleur-de-lis pattern LD flap, for total autologous breast reconstruction. Methods: Between 2016 and 2018, 23 patients were subjected to mastectomy and immediate autologous reconstruction with "extended latissimus dorsi kite flap" (ELD-K flap), technique that employs an extended version of the LD musculocutaneous flap, based on the skeletonized thoracodorsal pedicle and a trilobate skin incision with an inferiorly based vertical branch. The BREAST-Q questionnaire was administered preoperatively, and one year after surgery to evaluate the quality of life results of the patients. BREAST-Q latissimus dorsi module was also provided. Results: Average body mass index was 29.7 kg/m2 (range 25–40 kg/m2). Mild complications occurred in only six cases, and eight patients underwent treatment to improve the donor site scar outcome. Patients indicated high scores in quality of life measures with an increase in all BREAST domains from the preoperative to the postoperative period. A statistically significant increase (p < 0.05) was noted in: “overall satisfaction with breasts” (p < 0.05), “psychosocial well-being” (p < 0.05), “physical impact of the surgery” (p < 0.05). Within the LD module, participants reported a mean score of, respectively, 73.8 and 67.9 for “satisfaction with back” and “satisfaction with shoulder and back function” domains. Conclusions: The extended incision allows the recruitment of additional tissue to provide enough volume to complete the reconstruction without implants. The isolation of the vascular pedicle allows for extreme freedom and mobilization of the flap, ensuring adequate filling of the breast. ELD-K flap may expand the indications for a total autologous LD immediate breast reconstruction, representing an additional and reliable alternative in selected cohorts of patients. Level of Evidence IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266

Geophysics

Contains reports on four research projects.United States Air Force (Contract AF19(628)-500)Lincoln Laboratory (Purchase Order DDL BB-107

Patogenisitas Isolat Beauveria Bassiana Dan Metarhizium Anisopliae Asal Tanah Lebak Dan Pasang Surut Sumatera Selatan Untuk Agens Hayati Scirpophaga Incertulas

Pathogeicity of Beauveria bassiana and Metarhizium anisopliae Isolates from Fresh Swamp and Tidal Lowland, South Sumatra for Scirpophaga incertulas Biological Agents. The objectives of the research weret o explore and to determine the pathogenicity of entomopathogenic fungi againts the larvae of Scirpophaga incertulas, and to measure conidial viability and density of the fungi. The method for fungi exploration used larvae of Tenebrio molitor baiting submerged in the soil. The soil was taken from fresh swampand tidal lowland rice in South Sumatra. From the exploration study, we found two species of entomopathogenic fungi: Beauveria bassiana and Metarhizium anisopliae. Mortality of S. incertulas larvae that had been treated topically with fungal conidia (1x106 conidia ml-1) varied among the isolates. The highest mortality (98.33%) caused by BPlus isolate of B. Bassiana and the lowest by MtmIn isolate of M. anisopliae (57.50%) and BTmTr isolate of B. bassiana (57.50%). The fungal colonies grew fast from the second day up to the fourth day after incubation but the growth became slow after the fifth day. The highest conidial density was resulted by BPcMs of B. bassiana isolate (63.33x106 conidia ml-1) but this density was not significantly different from that of the BPlus of B. bassiana isolate (63.11x106 conidia ml-1). The lowest conidial density found in BTmTr of B. bassiana isolate (20.97x106 conidia ml-1) . The isolate B. bassiana was more effective than M. anisopliae againt the larvae of S.incertulas

Acral lentiginous melanoma. A retrospective study

Background: Acral lentiginous melanoma (ALM) carries one of the worst prognoses among other subtypes. This malignant tumor is found on the distal limbs and is usually detected at late stages. Hereby, the authors present their experience on this melanoma subtype. Methods: A retrospective study was conducted. Data were extracted from patients’ medical records and from phone interviews. Results: A total of 43 patients were included in the study. The main signs and symptoms disclosed by the patients were bleeding (41.9%), size greater than 6 mm (41.9%), change in size (37.2%), change in shape (30.2%), rise above the surface of the skin (27.9%), change in color (20.9%), irregular borders (16.3%), and inflammation (16.3%). The first healthcare professional consulted was a general practitioner or a dermatologist in the majority of cases (88.3%). Only 44.2% of the patients were sent by their first physician for a biopsy, whereas 30.3% were sent by the 2nd physician. 14 patients underwent biopsy within 1 month from the first appointment with a physician, while 20 patients within 3 months and 9 patients within 6 months. Only 7 patients sought medical attention in the first 3 months; 21 patients sought medical care between 3 months and one year from the appearance of the lesion, while the remaining 15 patients waited more than a year. Conclusions: One of the major issues found in ALM is represented by the diagnostic delay; this may be due to either the patients or the physicians’ failure to recognize warning signs