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Preliminary study of letrozole use for improving spermatogenesis in non-obstructive azoospermia patients with normal serum FSH

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Asian Journal of Andrology 2011年第6期13卷 895-897页

作者： Giorgio Cavallini Giovanni Beretta Giulio Biagiotti Andros-Italia Outpatient Clinic of Ferrara Via Mascheraio 46 Ferrara 44121 Italy Centro Italiano Fertilita e Sessualita Via della Fortezza 6 Firenze 50129 Italy Andros Italia Sede di Perugia Via Martiri dei Lager 58 Perugia 06128 Italy

We investigated whether letrozole （2.5 mg day-1） improves sperm count in non-obstructive azoospermia （NOA） patients. Four men were included in this study, and they had folliculo-stimulating hormone and other hormone levels within the normal range and no varicoceles or chromosomal aberrations. These four patients were administered letrozole for 3 months. Sperm count, testicular volume, gonadotropin, testosterone （T） and estradiol （E2） blood levels were assessed before, during and 1 week after the suspension of treatment. All patients showed spermatozoa in their ejaculate, increased gonadotropin and T levels and lower E2 levels （P〈0.05 in all cases）, when letrozole was administered. This suggests that letrozole treatment might improve sperm count in an NOA sub-population; however, more studies, including the proper controls, are needed to confirm its efficacy.

关键词： letrozole medical treatment non-obstructive azoospermia spermatogenesis

B1a lymphocytes in the rectal mucosa of ulcerative colitis patients

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World Journal of Gastroenterology 2012年第2期18卷 144-149页

作者： Lino Polese Riccardo Boetto Giuseppe De Franchis Imerio Angriman Andrea Porzionato Lorenzo Norberto Giacomo Carlo Sturniolo Veronica Macchi Raffaele De Caro Stefano Merigliano Department of Surgical and Gastroenterological Sciences University of PadovaVia Giustiniani 235128 PadovaItaly Department of Laboratory Medicine Padova University HospitalVia Giustiniani 235128 PadovaItaly Department of Human Anatomy and Physiology University of PadovaVia Gabelli 6535128 PadovaItaly

AIM:To assess B1a cell expression in the rectal mucosa of ulcerative colitis (UC) patients in comparison with healthy ***:Rectal mucosa biopsies were collected from 15 UC patients and 17 healthy ***5 + B cells were analysed by three colour flow cytometry from rectal mucosal samples after mechanical disaggregation by Medimachine.Immunohistochemical analysis of B and T lymphocytes was also *** between,on the one hand,rectal B1a cell concentrations and,on the other,erythrocyte sedimentation rate and C-reactive protein levels and clinical,endoscopic and histological disease activity indices were ***:Rectal B-lymphocyte (CD19 + /CD45 +) rate and concentration were higher in UC patients compared with those in healthy controls (47.85% ± 3.12% vs 26.10% ± 3.40%,P=0.001 and 501 ± 91 cells/mm 2 vs 117 ± 18 cells/mm 2,P < 0.001);Rectal B1a cell density (CD5 + CD19 +) was higher in UC patients than in healthy controls (85 ± 15 cells/mm 2 vs 31 ± 6.7 cells/mm 2,P=0.009).Rectal B1a cell (CD5/CD19 +) rate correlated inversely with endoscopic classification (Rs=-0.637,P < 0.05).CONCLUSION:B1a lymphocytes seem to be involved in the pathogenesis of UC,however,the role they play in its early phases and in disease activity,have yet to be defined.

关键词： B1 cell CD5 Flow cytometry Rectum Ulcerative colitis

Multiple aspects of the maternal reproductive investmentin a polytocous species:What do mothers really control?

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Current Zoology 2023年第2期69卷 136-142页

作者： Rudy Brogi Roberta Chirichella Enrico Merli Marco Apollonio Department of Veterinary Medicine University of Sassarivia Vienna 2I-07100 SassariItaly Department of Humanities and Social Sciences University of Sassarivia Roma 151I-07100 SassariItaly

One of the factors facilitating the expansion and proliferation of wild boar Sus scrofa is the plasticity of its reproductive ***,the real influence of maternal and environmental factors on number and sex of the offspring is stll *** the litter size was shown to be related with the maternal condition,the strength of this relation remains to be understood,together with the possible role played by environmental ***,it is unclear whether wild boar females can adjust their offspring *** investigated multiple aspects of wild boar maternal investment by means of a 10-year dataset of female reproductive traits and a set of biologically meaningful environmental *** maternal condition slightly affected the litter size but not the offspring sex,and environment did not affect the litter size or the offspring ***,mothers did not cope with the higher costs entailed by producing sons by placing them in the most advantageous intrauterine position,nor by allocating less resources on *** set of results showed that the female reproductive investment is quite rigid in comparison with other aspects of wild boar reproductive *** boar females seem to adopt a typical rstrategy,producing constantly large litters and allocating resources on both sexes regardless of internal and external *** strategy may be adaptive to cope with environmental unpredictability and an intense human harvest,contributing to explain the extreme success of wild boar within human-dominated landscapes.

关键词： investment life history litter size reproduction sex allocation wild boar

INNOVATIVE SOLUTIONS BASED ON SIMULATION COMBINED WITH OPTIMIZATION TECHNIQUES FOR MAINTENANCE SERVICE MANAGEMENT WITHIN COMPLEX SYSTEMS

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International Journal of Modeling, Simulation, and Scientific Computing 2012年第2期3卷 19-41页

作者： AGOSTINO BRUZZONE ENRICO BOCCA MISS DIME University of Genoa via Opera Pia 15 16145 GenovaItaly MAST Srl Via Biga 2616144 GenovaItaly

The research proposes a simulation model combined with smart optimizer based onArtificial Intelligence techniques, in order to support service and maintenance of poolswithin Complex Systems, such as power plants or vessel/aircraft *** authors propose an innovative methodology allowing the evaluation and theoptimization of service and maintenance policies in order to improve inventory management and scheduling operations within complex systems. This methodology is based onthe development of a simulator combined with an intelligent *** authors proposed a new metrics to evaluate the real performance of pool servicemanagement of the whole complex system and support the optimization processes.

关键词： Simulation power plants maintenance decision support system complex system optimization.

=actors influencing wild boar damage to agricultural crops in Sardinia （Italy）

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Current Zoology 2017年第5期63卷 507-514页

作者： Marco LOMBARDINI Alberto MERIGGI Alberto FOZZL Department of Earth and Environmental Sciences University of Pavia Via Ferrata 1 27100 Pavia Italy Province of Olbia-Tempio Via A. Nanni 17/19 07026 01bia Italy

Crop damage by wildlife is a frequent source of human-wildlife conflict. Understanding which fac-tors increase the risk of damage is crucial to the development of effective management *** aims of this study were to provide a general description of agricultural damage caused by wildboar Sus scrofa meridionalis over a 7-year period in North-eastern Sardinia （Mediterranean Italy）,and to formulate a predictive model of damage risk. We recorded a total of 221 cases of wild boardamage, with economic losses amounting to 483,982 Euros. Damage events mostly involved vine-yards, meadows and oat fields, and were characterized by a peak incidence in summer and earlyautumn, and a minimum in spring. Damaged fields were characterized by an increasing presenceof permanent crops, a decreasing presence of woodlands, maquis and urban areas, and a reduceddistance from shelter areas （forests and shrublands）. The analysis of spatiotemporal variation ofboar-induced damage and the identification of factors that augment the risk of damage providesessential information for contributing to the development of a more effective plan for managingwild boar populations.

关键词： Human-wildlife conflict, Sus scrofa meridionalis, risk modelling, landscape structure, wild boar management.

Frequency-dependent flight activity in the colour polymorphic wood tiger moth

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Current Zoology 2015年第4期61卷 765-772页

作者： Bibiana ROJAS Swanne R GORDON Johanna MAPPES University of Jyvaskyla Centre of Excellence in Biological Interactions Department of Biology and Environmental Sciences POBox 35 FI 40001 Finland

Predators efficiently learn to avoid one type of warning signal rather than several, making colour polymorphisms un- expected. Aposematic wood tiger moth males Parasemia plantaginis have either white or yellow hindwing coloration across Eu- rope. Previous studies indicate that yellow males are better defended from predators, while white males have a positively frequency-dependent mating advantage. However, the potential frequency-dependent behavioural differences in flight between the morphs, as well as the role of male-male interactions in inducing flying activity, have not been previously considered. We ran an outdoor cage experiment where proportions of both male morphs were manipulated to test whether flying activity was frequency- dependent and differed between morphs. The white morph was significantly more active than the yellow one across all treatments, and sustained activity for longer. Overall activity for both morphs was considerably lower in the yellow-biased environment, suggesting that higher proportions of yellow males in a population may lead to overall reduced flying activity. The activity of the yellow morph also followed a steeper, narrower curve than that of the white morph during peak female calling activity. We sug- gest that white males, with their presumably less costly defences, have more resources to invest in flight for predator escape and finding mates. Yellow males, which are better protected but less sexually selected, may instead compensate their lower flight ac- tivity by ＇flying smart＇ during the peak female-calling periods. Thus, both morphs may be able to behaviourally balance the trade-off between warning signal selection and sexual selection. Our results emphasize the greater need to investigate animal behaviour and colour polymorphisms in natural or semi-natural environments [Current Zoology 61 （4）： 765-772, 2015].

关键词： Frequency-dependent selection Flight Colour polymorphism Sexual selection Aposematism

An innovative orbital implant positioner for the proper restoration of eye-socket defects

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Bio-Design and Manufacturing 2023年第1期6卷 82-89页

作者： Marco Mandolini Agnese Brunzini Manila Caragiuli Alida Mazzoli Mario Pagnoni Department of Industrial Engineering and Mathematical Sciences UniversitàPolitecnica Delle MarcheVia Brecce Bianche 1260131 AnconaItaly Department of Materials Environmental Sciences and Urban PlanningUniversitàPolitecnica Delle MarcheVia Brecce Bianche 1260131 AnconaItaly yourFACE Clinica Ars BiomedicaVia Luigi Bodio 5800191 RomeItaly

Fractures to the orbital walls and floor must be appropriately managed to avoid severe *** results in particularly challenging anatomical *** main issues are the implant’s proper shaping,placement,and orientation onto the eye socket.A new,customized implant-shaping mould has already been developed to shape patient-specific ***,it still does not address the implant positioning in the fractured orbital cavity.

关键词： socket orbital walls

A Design of Single-Switch Two-Stage DC-DC Converters With PWM And PFM for Off-Grid Solar Power System

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Chinese Journal of Electrical Engineering 2017年第3期3卷 44-51页

作者： Junkai Zhao Herbert H.C.Iu Tyrone Fernando School of Electrical Electronic and Computer EngineeringThe University of Western Australia35 Stirling HighwayCrawleyWA 6009Australia

In this paper,a single-switch two-stage DC-DC conversion circuit is proposed for an off-grid solar power application.A photovoltaic(PV)panel powers the load and a storage unit(battery)via the proposed *** battery is designed to balance the supply and the demand of power under different irradiation *** on conventional cascaded DC-DC converters,the proposed design is developed with the single switch technique reducing size,cost and power *** control scheme in this design is pulse width modulation(PWM)with pulse frequency modulation(PFM).The PWM module is similar to conventional design except its ramp signal with a variable frequency is provided by a resettable *** a result,the PWM and PFM modules regulate the two stages of the proposed circuit separately with the same switching control *** this paper,the modes of operation of the circuit are discussed as well as the control *** design process is described along with the circuit analysis and comparisons with conventional design are made as well.A prototype has been built to verify the proposed circuit with simulation and experimental results.

关键词： Single-switch technique photovoltaic power system off-grid solar system DC-DC conversion resettable integrator pulse frequency modulation(PWM) pulse width modulation(PFM)

Pyrolysis of WEEE plastics using catalysts produced from fly ash of coal gasification

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Frontiers of Environmental Science & Engineering 2017年第5期11卷 113-123页

作者： Marika Benedetti Lorenzo Cafiero Doina De Angelis Alessandro Dell'Era Mauro Pasquali Stefano Stendardo Riceardo Tuffi Stefano Veechio Ciprioti Department for Sustainability ENEA - Casaccia Research Center Via Anguillarese 301 S. Maria di Galeria Rome Italy Department of SBAI Sapienza University of Rome Via del Castro Laurenziano 7 00161 Rome Italy Department of Energy Technologies ENEA Casaccia Research Center Via Anguillarese 301 S. Mafia di Galeria Rome Italy

Catalytic pyrolysis of thermoplastics extracted from waste electrical and electronic equipment （WEEE） was investigated using various fly ash-derived catalysts. The catalysts were prepared from fly ash by a simple method that basically includes a mechanical treatment followed by an acid or a basic activation. The synthesized catalysts were characterized using various analytical techniques. The results showed that not treated fly ash （FA） is characterized by good crystallinity, which in turn is lowered by mechanical and chemical treatment （fly ash after mechanical and acid activation, FAMA） and suppressed almost entirely down to let fly ash become completely amorphous （fly ash al^er mechanical and basic activation FAMB）. Simultaneously, the surface area resulted increased. Subsequently, FA, FAMB and FAMA were used in the pyrolysis of a WEEE plastic sample at 400~C and their performance were compared with thermal pyrolysis at the same temperature. The catalysts principally improve the light oil yield： from 59 wt.% with thermal pyrolysis to 83 wt.% using FAMB. The formation of styrene in the oil is also increased： from 243 mg/g with thermal pyrolysis to 453 mg/g using FAMB. As a result, FAMB proved to be the best catalyst, thus producing also the lowest and the highest amount of char and gas, respectively.

关键词： Waste electrical and electronic equipment(WEEE) plastic mixture Pyrolysis Catalyst Fly asla Oil