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

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

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A Statistical Study of Magnetic Flux Emergence in Solar Active Regions Prior to Strongest Flares

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Research in Astronomy and Astrophysics 2024年第4期24卷 147-160页

作者： Alexander S.Kutsenko valentina I.Abramenko Andrei A.Plotnikov Crimean Astrophysical Observatory p/o NauchnyCrimea298409Russia

Using the data on magnetic field maps and continuum intensity for Solar Cycles 23 and 24,we explored 100 active regions(ARs)that produced M5.0 or stronger *** focus on the presence/absence of the emergence of magnetic flux in these ARs 2-3 days before the strong flare *** found that 29 ARs in the sample emerged monotonically amidst quiet-Sun.A major emergence of a new magnetic flux within a pre-existing AR yielding the formation of a complex flare-productive configuration was observed in another 24 *** 30 ARs,an insignificant(in terms of the total magnetic flux of pre-existing AR)emergence of a new magnetic flux within the pre-existing magnetic configuration was observed;for some of them the emergence resulted in a formation of a configuration with a small δ-sunspot;11 out of 100 ARs exhibited no signatures of magnetic flux emergence during the entire interval of *** six cases the emergence was in progress when the AR appeared on the Eastern limb,so that the classification and timing of emergence were not *** conclude that the recent flux emergence is not a necessary and/or sufficient condition for strong flaring of an *** flux emergence rate of flare-productive ARs analyzed here was compared with that of flare-quiet ARs analyzed in our previous *** revealed that the flare-productive ARs tend to display faster emergence than the flare-quiet ones do.

关键词： Sun:activity Sun:flares Sun:magnetic fields

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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

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Efficiency Analysis of Promotion of Chinese Tea on Russian Market

Efficiency Analysis of Promotion of Chinese Tea on Russian M...

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作者： Lyssenko valentina（白龙）南昌大学

学位级别：硕士

It is top-important for each company that sells Chinese tea to use promotion tools in the best possible way to achieve increase of *** will influence increase of purchase tea from *** purpose of this research work is to analyze efficiency of different promotion mix tools of marketing that influence sales of Chinese tea-based trademark “Inspiration” on local Russian *** the literature overview concept of “promotion” was analyzed and the main objectives of the promotion activity were defined,the communication process that connects the sender and the recipient of the marketing message was also *** functions of the promotion mix,as well as its structure,were *** on the analysis of the literature,it was concluded that there are several points of view on the structure of the promotion ***,there are four elements of the promotion mix: advertising,sales promotion,PR,personal *** of lirerature helped to develop extended promotion mix concept which includes the following elements: advertising,sales promotion,personal selling,PR,direct marketing,sponsorship,product placement,branding,exhibitions and fairs,corporate identity,packaging,information *** describing the generalized structure of the promotion mix,elements were selected to analyze their efficiency in *** the methodology systematization,generalization and classification of existing methods for evaluating the efficiency of promotion mix elements were *** basic concepts of efficiency were *** was determined what place the evaluation of the efficiency of the promotion in the overall sequence of evaluation of the marketing activities of the *** main directions for evaluating the efficiency were also outlined: an analysis of the costefficiency of campaigns,an assessment of communicative efficiency,an analysis of information efficiency,an assessment of the channels of information dissemination,an assessment of the quali

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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

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Progress in Natural Science:Materials International 2015年第2期25卷 122-130页

作者： valentina Mitran Madalina Georgiana Albu Eugeniu Vasile Anisoara Cimpean Marieta Costache University of Bucharest Faculty of Biology Department of Biochemistry and Molecular Biology INCDTP – Division Leather and Footwear Research Institute Collagen Department 3. University Politehnica of Bucharest Advanced Polymer Materials Group

This paper aims at demonstrating the biocompatibility of recently developed 3D hydrogel scaffolds containing the same amount of collagen(COLL) and variable concentrations of sericin(SS) in order to find the most suitable formula for adipose tissue engineering(ATE) *** scaffolds were obtained by COLL crosslinking with glutaraldehyde followed by freeze-drying and, subsequently, seeded with 3T3-L1 preadipocytes. Scanning electron microscopy studies revealed the scaffolds’ architecture and cellular colonization. Also, in vitro biocompatibility of the developed scaffolds was evaluated by LDH and MTT assays and Live/Dead analysis of 3T3-L1 preadipocyte populating these 3D *** best results in terms of cell survival and proliferation status were obtained in the case of the hybrid COLL scaffold containing 40% SS(COLL–SS4). Furthermore, the biological performance of the analyzed COLL-based hydrogels at 5- and 8- days post-seeding was found to decrease as follows: COLL–SS4 4 COLL–SS2 4 COLL 4 COLL–SS6. Consequently, our study highlights that hybrid scaffolds obtained by the addition of variable concentrations of SS to a constant COLL composition positively influences the behavior of 3T3-L1 cells with the exception of the COLL–SS6 matrix(60% SS). Altogether, the data obtained recommend SS as a component of COLL-based hydrogels providing them with features that may be useful in ATE applications.

关键词： Sericin–collagen scaffold Preadipocyte Proliferation Morphology Tissue engineering

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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

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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

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Microbiological characterization of a rearing system for the common sea urchin Paracentrotus lividus:a support to technical production regulations redaction and system monitoring

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Food Quality and Safety 2024年第3期8卷 603-610页

作者： Sara Maria Pani valentina Coroneo Viviana Pasquini Adriana Sanna Piero Addis Department of Medical Sciences and Public Health University of CagliariMonserratoItaly Department of Life and Environmental Science University of CagliariCagliariItaly

Objective:The overexploitation of the sea urchin Paracentrotus lividus stock,as a consequence of the growing market demand for roe,has boosted the research for echinoderm *** chemical,physical,and microbiological characteristics of land-based facilities are crucial for sea urchins’health and human consumption of their *** Italy,health-hygienic regulations for *** rearing are still to be perfected by the *** this context,we characterized the microbiological quality of a pilot land-based facility for sea urchin production at the University of Cagliari(Italy)to support the development of technical production *** and Methods:The accredited Hygiene Laboratory of Cagliari University collected and analyzed the samples in June *** bacteria,yeasts,and molds were searched for in air and on *** coliforms and Escherichia coli,Enterococci,Pseudomonadaceae,Staphylococcus aureus,sulfite-reducing Clostridia,and Vibrio *** identified in water *** searched forVibrio *** Pseudomonas *** the gonads and coelomic fluid of sea ***:Although air,surfaces,and water quality were satisfactory overall,some critical points should be monitored more *** concentration was 250 CFU/100 mL in the water reserve,suggesting animal contamination(other than humans).Pseudomonas aeruginosa was the most resistant to filtration processes,with a residual concentration of 6 CFU/250 mL after the second *** colonies of Vibrio *** Pseudomonas *** isolated in sea urchins’gonads or coelomic ***:Starting from the results,we provided targeted advice for developing technical production regulations,system monitoring,and facility routine maintenance in accordance with the‘best practice’*** analysis could be considered a first step toward the elaboration of common regulations about the minimal standards for the breeding environment of *** by national and r

关键词： Paracentrotus lividus echinoculture health hazards microbial contaminants production disciplinary Sardinia

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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

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