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Obligatory parthenogenesis and TE load： Bacillus stick insects and the R2 non-LTR retrotransposon

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Insect Science 2017年第3期24卷 409-417页

作者： Livia Bonandin Claudia Scavariello valentina Mingazzini Andrea Luchetti Barbara Mantovani Dipartimento di Scienze Biologiche Geologiche e Ambientali Universit~ di Bologna Bologna Italy

Transposable elements （TEs） are selfish genetic elements whose self-replication is contrasted by the host genome. In this context, host reproductive strategies are predicted to impact on both TEs load and activity. The presence and insertion distribution of the non- LTR retrotransposon R2 was here studied in populations of the strictly bisexual Bacillus grandii maretimi and of the obligatory parthenogenetic Bacillus atticus atticus. Further- more, data were also obtained from the offspring of selected B. a. atticus females. At the population level, the gonochoric B. g. maretimi showed a significantly higher R2 load than the obligatory parthenogenetic B. a. atticus. The comparison with bisexual and unisexual Bacillus rossius populations showed that their values were higher than those recorded for B. a. atticus and similar, or even higher, than those of B. g. maretimi. Consistently, an R2 load reduction is scored in B. a. atticus offspring even if with a great variance. On the whole, data here produced indicate that in the obligatory unisexual B. a. atticus R2 is active and that mechanisms of molecular turnover are effective. Furthermore, progeny analyses show that, at variance of the facultative parthenogenetic B. rossius, the R2 activ- ity is held at a lower rate. Modeling parental-offspring inheritance, suggests that in B. a. atticus recombination plays a major role in eliminating insertions rather than selection, as previously suggested for unisexual B. rossius progeny, even if in both cases a high variance is observed. In addition to this, mechanisms of R2 silencing or chances of clonal selection cannot be ruled out.

关键词： insertion activity Muller's ratchet Phasmida recombination retrotranspo-son unisexuality

Digital Media Strategies:Online Video Marketing in the Fashion Industry

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Digital Media Strategies:Online Video Marketing in the Fashi...

作者： valentina Iacuitto 复旦大学

学位级别：硕士

在线视频是新媒体领域最流行和最重要的发展趋势之一。越来越多的人通过电脑,手机和其他手持终端在线观看视频。因此,在线视频成为了很多厂家和消费者沟通,并传达品牌信息的重要渠道。当你的目标客户是那些在互联网上花费很多时间的人... 详细信息

在线视频是新媒体领域最流行和最重要的发展趋势之一。越来越多的人通过电脑,手机和其他手持终端在线观看视频。因此,在线视频成为了很多厂家和消费者沟通,并传达品牌信息的重要渠道。当你的目标客户是那些在互联网上花费很多时间的人时尤其如此。厂家有多种不同的方式参与线上营销。除了传统的付费广告之外,厂家还可以尝试自主运营的模式。本文旨在研究时尚行业的公司是否能有效地通过在线视频推广他们的品牌。研究表明尽管大多数时尚行业的公司都参与了线上营销,且大多数采用自主运营模式,但是极少数公司能够制定全面而创新的营销方案。这些极少数的充满创意的在线视频使得这些公司可以通过创新的方式达成传统的营销目标,充分展示了此类营销手段的广阔前景。然而,这些有限的成功个案还不足以引领整个行业,带来线上营销爆棚式的发展。

关键词： Digital Online Video Fashion

A Postcolonial Perspective on the Evolution of National Identity in the Novels of Margaret Atwood

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A Postcolonial Perspective on the Evolution of National Iden...

作者： Frolova valentina 华中师范大学

学位级别：硕士

The question of national identity is one of the most contradictory ones in postcolonial era and postcolonial *** can be considered the most important issue due to the existence of the identity crisis in all postcolonial *** process of decolonization of the countries subjected to colonial rule triggered a remarkable movement towards restoration of the national identities of the newly freed *** wasn’t an *** phenomenon is explored in most of Margaret Atwood’s novels,yet it has never so far become the subject of a full-scale analysis throughout the author’s entire fictional *** study examines the process of Canadian national identity’s evolution and transformation,reflected in the novels of ***,through the prism of postcolonial critical *** primary material consists of seven novels:The Edible Woman（1969）,Surfacing（1972）,Lady Oracle（1976）,Life Before Man（1979）,Cat’s Eye（1988）,The Robber Bride（1993）and The Blind Assassin（2000）.Grounding arguments in the works of theorists in the sphere of national identity including Benedict Anderson’s study on national identity’s construction,Northrop Frye’s study on Canadian identity crisis,Edward Said’s Orientalism,***’s research on the production of discriminatory identities the researcher attempts to conduct a deeper analysis of ***’s views on the problem of national identity’s acquisition by *** thesis’s methodological basis lies in postcolonial literary criticism and new historical literary *** of these approaches are necessary in order to reach an adequate understanding of the author’s philosophical and ideological position,that is,the influence of the question of the national identity’s recreation in a postcolonial society on Atwood’s literary *** study also examines the reverse process,*** influence of ***’s novels on the process of strengthening the national identity of the Canadian *** thesis is divided into s

关键词： Canadian literature Margaret Atwood identity formation national identity postcolonial critical theory new historicism

Liver transplantation for Wilson disease

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World Journal of Hepatology 2012年第1期4卷 5-10页

作者： Andreea M Catana valentina Medici Division of Gastroenterology and Hepatology Department of Internal MedicineUniversity of California

The aim of this paper is to review the current status of liver transplantation (LT) for Wilson disease (WD), focusing on indications and controversies, especially in patients with neuropsychiatric disease, and on identification of acute liver failure (ALF) cases related to WD. LT remains the treatment of choice for patients with ALF, as initial presentation of WD or when anti-copper agents are stopped, and for patients with chronic liver disease progressed to cirrhosis, unresponsive to chelating medications or not timely treated with copper chelating agents. The indication for LT in WD remains highly debated in patients with progressive neurological deterioration and failure to improve with appropriate medical treatment. In case of Wilsonian ALF, early identification is key as mortality is 100% without emergency LT. As many of the copper metabolism parameters are believed to be less reliable in ALF, simple biochemical tests have been proposed for diagnosis of acute WD with good sensitivity and specificity. LT corrects copper metabolism and complications resulting from WD with excellent 1 and 5 year survival. Living related liver transplantation represents an alternative to deceased donor LT with excellent long-term survival, without disease recurrence. Future options mayinclude hepatocyte transplantation and gene therapy. Although both of these have shown promising results in animal models of WD, prospective human studies are much needed to demonstrate their long-term beneficial effects and their potential to replace the need for medical therapy and LT in patients with WD.

关键词： Wilson disease Liver transplantation Copper Indications Contraindications

Catalytic Kinetic Spectrophotometric Method for Determination of Phosphate Ion

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Chinese Journal of Chemistry 2007年第4期25卷 531-534页

作者： MITIC Snezana ZIVANOVIC valentina OBRADOVIC Mirjana TOSIC Snezana PAVLOVIC Aleksandra Faculty of Sciences and Mathematics Department of Chemistry University of Nig Visegradska 33 P.O. Box 224 18000 Nis Serbia

The kinetic method for the determination of phosphate microamounts was described. The developed method is based on catalytic effect of phosphate on sodium pyrogallol-5-sulphonate （PS） by dissolved oxygen. The reaction was followed spectrophotometrically by measuring the rate of change in the values of the absorbance of the oxidation product at 437 nm. The optimum reaction conditions are PS （0.44×10^-3 mol·L^-1） and HClO4 （3.6×10^-6 mol·L^-1） at 25 ℃. Following this procedure, phosphate can be determined with a linear calibration graph up to 0.23 μg·mL^-1. The interference effect of several species was also investigated and it was found that the most common cations and anions did not interfere with the determination. The developed procedure was successfully applied to the determination of phosphate in natural waters and soil.

关键词： kinetic spectrophotometric method sodium pyrogallol-5-sulphonate phosphate oxygen oxidation determination water soil

Endoluminal vacuum-assisted therapy as a treatment for anastomotic leakage in colorectal surgery

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World Journal of Gastroenterology 2022年第28期28卷 3747-3752页

作者： Maria Michela Chiarello valentina Bianchi Pietro Fransvea Giuseppe Brisinda Department of Surgery Azienda Sanitaria Provinciale di CosenzaCosenza 87100Italy Emergency Surgery and Trauma Center Fondazione Policlinico Universitario A Gemelli IRCCSRome 00168taly Medical and Surgical Sciences Fondazione Policlinico Universitario A Gemelli IRCCSRome 00168Italy

Anastomotic leakage(AL)has a wide range of clinical features ranging from radiological only findings to peritonitis and sepsis with multiorgan *** early diagnosis of AL is essential in order to establish the most appropriate treatment for this *** AL continues to be a dreadful complication after colorectal surgery,there has been no consensus on its ***,based on patient’s presentation and timing of the AL,there has been a gradual shift to a more conservative management,keeping surgery as the last option Reoperation for sepsis control is rarely necessary especially in those patients who already have a diverting stoma at the time of the leak.A nonoperative management is usually preferred in these *** are several treatment options,also for patients without a stoma who do not require a reoperation for a contained pelvic leak,including recently developed endoscopic procedures,such as clip placement or endoluminal vacuum-assisted *** conservative treatments could be an option in patients who are clinically stable or in presence of a small defect.

关键词： Anastomotic leakage Colorectal cancer Colorectal surgery Mortality Morbidity

Ultralong and Mesoporous ZnO and γ-Al_2O_3 Oriented Nanowires Obtained by Template-assisted Hydrothermal Approach

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Journal of Materials Science & Technology 2014年第12期30卷 1167-1173页

作者： Carminna Ottone Vivian Farías Rivera Marco Fontana Katarzyna Bejtka Barbara Onida valentina Cauda Center for Space Human Robotics Polito Istituto Italiano di Tecnologia Corso Trento 21 Turin Italy Dipartimento di Scienza Applicata e Tecnologia (DISAT) Politecnico di Torino Corso Duca Degli Abruzzi 24 Turin Italy

Highly mesoporous Zn O and g-Al2O3nanowires（NWs） are both synthesized by a hydrothermal method using commercially available porous anodic aluminium oxide（AAO） as template. AAO membrane acts as template for Zn O NWs and both as template and precursor for g-Al2O3 NWs. The formation of intermediate phases of porous Zn6Al2（OH）16CO3and boehmite（g-Al OOH） were observed, both occurring during the hydrothermal synthesis of porous Zn O and g-Al2O3 NWs, respectively, and disappearing after annealing at 600 C. This novel template-assisted hydrothermal process leads to the formation of porous Zn O and g-Al2O3NWs（specific surface area of 192 m2 g 1and 263 m2 g 1, respectively）, showing pore sizes around 4 nm in diameter. The influence of the reaction parameters on the nanostructure morphology was also investigated. A Zn O seed layer, deposited on the AAO channels prior to the hydrothermal synthesis, leads to more compact Zn O nanowires（99 m2 g-1） protecting the AAO host from the chemical attack of the precursor solution.

关键词： Mesoporous ZnO nanowires Mesoporous γ-Al2O3 nanowires Boehmite Template-assisted method Hydrothermal synthesis

Effect of grassland mosaic structure and dynamism on the reproductive habitat suitability for Alectoris graeca in central Apennines

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Journal of Mountain Science 2019年第12期16卷 2783-2792页

作者： Andrea BRUSAFERRO valentina IESARI Federico Maria TARDELLA Paola SCOCCO Andrea CATORCI School of Biosciences and Veterinary Medicine University of Camerino

Over the last several decades,the Mediterranean region has been subjected to mountain abandonment and farming cessation,leading to changes in vegetation and coenological features of grasslands,contextually to the strong decline of the rock partridge(Alectoris graeca).Our hypothesis was that the ongoing dynamic processes leading to the compositional changes of grasslands in central Apennines affect the habitat suitability for the singing male(territorial male defending its reproductive site).In 2015,we defined the presence/absence of spring territorial singing males in seven sites(1,250-2,400 m a.s.l.),by the census in 74 playback stations,distributed along 15 *** characterized the topography and the vegetation mosaic of such sites according to the collected topographic and vegetation cover data in 59 randomly selected plots(100 m×100 m)along the *** understand the relations among the environmental variables and the effect of the composition and dynamism of the vegetation mosaics on the presence/absence of the singing male,we used principal components analysis and generalized linear mixed-effect *** results emphasized the marked overlap between the general environmental conditions,which proved to define the habitat suitability for ***,and the characteristics of the site chosen by the singing male for starting the reproductive ***,we found that the site suitability for the singing male decreases when the vegetation recovery processes are ongoing,because of the spread of coarse tall grassesdominated communities and/or grassland types with dense *** grass-dominated communities and thick-turf grasslands exert their negative effect decreasing the habitat suitability for the singing male starting from low cover ***,it is conceivable that singing male’s suitable habitat will be dramatically restricted to the steepest south-facing slopes,where topographic and soil conditions do not allow the spread of grassl

关键词： Brachypodium genuense Grazing cessation Reproductive habitat suitability Rock partridge Singing male Vegetation recovery processes

Poly(NIPAM-co-MPS)-grafted multimodal porous silica nanoparticles as reverse thermoresponsive drug delivery system

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Asian Journal of Pharmaceutical Sciences 2017年第3期12卷 279-284页

作者： Sushilkumar A.Jadhav valentina Brunella Dominique Scalarone Gloria Berlier Department of Chemistry and NIS Research Centre University of Torino

Hybrid drug delivery systems(DDS) have been prepared by grafting poly(NIPAM-co-MPS) chains on multimodal porous silica nanoparticles having an inner mesoporous structure and an outer thin layer of micropores. The hybrid thermoresponsive DDS were fully characterized and loaded with a model drug. The in vitro drug release tests are carried out at below and above the lower critical solution temperature(LCST) of the copolymer. The results have revealed that due to the presence of small diameter(~1.3 nm) micropores at the periphery of the particles, the collapsed globules of the thermoresponsive copolymer above its LCST hinders the complete release of the drug which resulted in a reverse thermoresponsive drug release profile by the hybrid DDS.

关键词： Porous silica nanoparticles Thermoresponsive polymer Drug delivery system Ibuprofen Drug loading Drug release profile