Revisão de modelos matemáticos da dinâmica do banco de sementes de plantas daninhas em agrossistemas.

O crescimento das plantas obedece a certos princípios fisiológicos, que podem ser descritos em termos quantitativos, até certo ponto, por equações matemáticas. No ambiente agrícola, a dinâmica do banco de sementes está fortemente relacionada ao estabelecimento de espécies daninhas e pode ser descrita por um sistema de equações que relaciona a densidade de plântulas com a densidade de sementes produzidas em áreas de cultivo. O objetivo deste artigo foi descrever, através de modelos matemáticos citados na literatura, as características do comportamento dinâmico do banco de sementes de populações de plantas daninhas em sistemas agrícolas

The entrepreneurial finance markets of the future: a comparison of crowdfunding and initial coin offerings

This is the final version. Available from Springer Verlag via the DOI in this record. Entrepreneurial finance markets are in a dynamic state. New market niches and players have developed and continue to emerge. The rules of the game and the methods for receiving financial backing have changed in many ways. This editorial and the special issue of Small Business Economics focus on crowdfunding (CF) and initial coin offerings (ICOs), which are two distinct but important entrepreneurial finance market segments of the future. Although the two market segments initially appear to be similar, we identify differences between them. Our comparison focuses on the stakeholders, microstructures, regulatory environments, and development of the markets. We conclude with suggestions for future ICO and CF research.Projekt DEA

Micro- and Nanoplastics’ Effects on Protein Folding and Amyloidosis

A significant portion of the world's plastic is not properly disposed of and, through various processes, is degraded into microscopic particles termed micro- and nanoplastics. Marine and terrestrial faunae, including humans, inevitably get in contact and may inhale and ingest these microscopic plastics which can deposit throughout the body, potentially altering cellular and molecular functions in the nervous and other systems. For instance, at the cellular level, studies in animal models have shown that plastic particles can cross the blood-brain barrier and interact with neurons, and thus affect cognition. At the molecular level, plastics may specifically influence the folding of proteins, induce the formation of aberrant amyloid proteins, and therefore potentially trigger the development of systemic and local amyloidosis. In this review, we discuss the general issue of plastic micro- and nanoparticle generation, with a focus on their effects on protein folding, misfolding, and their possible clinical implications

A refinement approach in a mouse model of rehabilitation research. analgesia strategy, reduction approach and infrared thermography in spinal cord injury

The principles of Refinement, Replacement and Reduction (3R's) should be taken into account when animals must be used for scientific purpose. Here, a Reduction / Refinement approach was applied to the procedure of spinal cord injury (SCI), an animal model used in rehabilitation medicine research, in order to improve the quality of experiments, avoiding unnecessary suffering. The aims of this investigation were 1- to assess acute surgical pain in mice subjected to SCI, 2- to compare the efficacy of commonly used analgesia (three buprenorphine subcutaneous injection in 48 hours, 0,15 mg/kg each) with a combination of opioid and NSAID (one subcutaneous injection of 5 mg/kg carprofen before surgery followed by three buprenorphine subcutaneous injection in 48 hours, 0,15 mg/kg each) and 3- to test if Infrared Thermography (IRT) could be a potential new Refinement method to easily assess thermoregulation, an important metabolic parameter. Finally, we aimed to achieve these goals without recruiting animals on purpose, but using mice already scheduled for studies on SCI. By using behaviours analysis, we found that, despite being commonly used, buprenorphine does not completely relieve acute surgical pain, whereas the combination of buprenorphine and carprofen significantly decreases pain signs by 80%. IRT technology turned out to be a very useful Refinement tool being a non invasive methods to measure animal temperature, particularly useful when rectal probe cannot be used, as in the case of SCI. We could find that temperatures constantly and significantly increased until 7 days after surgery and then slowly decreased and, finally, we could observe that in the buprenorphine and carprofen treated group, temperatures were statistically lower than in the buprenorphine-alone treated mice. To our knowledge this is the first work providing an analgesic Refinement and a description of thermoregulatory response using the IRT technology, in mice subjected to SCI

Mercury clathration-driven phase transition in a luminescent bipyrazolate metal-organic framework: a multitechnique investigation

Mercury is one of the most toxic heavy metals. By virtue of its triple bond, the novel ligand 1,2-bis(1H-pyrazol-4-yl)ethyne (H2BPE) was expressly designed and synthesized to devise metal-organic frameworks (MOFs) exhibiting high chemical affinity for mercury. Two MOFs, Zn(BPE) and Zn(BPE)·nDMF [interpenetrated i-Zn and noninterpenetrated ni-Zn·S, respectively; DMF = dimethylformamide], were isolated as microcrystalline powders. While i-Zn is stable in water for at least 15 days, its suspension in HgCl2 aqueous solutions prompts its conversion into HgCl2@ni-Zn. A multitechnique approach allowed us to shed light onto the observed HgCl2-triggered i-Zn-to-HgCl2@ni-Zn transformation at the molecular level. Density functional theory calculations on model systems suggested that HgCl2 interacts via the mercury atom with the carbon-carbon triple bond exclusively in ni-Zn. Powder X-ray diffraction enabled us to quantify the extent of the i-Zn-to-HgCl2@ni-Zn transition in 100-5000 ppm HgCl2 (aq) solutions, while X-ray fluorescence and inductively coupled plasma-mass spectrometry allowed us to demonstrate that HgCl2 is quantitatively sequestered from the aqueous phase. Irradiating at 365 nm, an intense fluorescence is observed at 470 nm for ni-Zn·S, which is partially quenched for i-Zn. This spectral benchmark was exploited to monitor in real time the i-Zn-to-HgCl2@ni-Zn conversion kinetics at different HgCl2 (aq) concentrations. A sizeable fluorescence increase was observed, within a 1 h time lapse, even at a concentration of 5 ppb. Overall, this comprehensive investigation unraveled an intriguing molecular mechanism, featuring the disaggregation of a water-stable MOF in the presence of HgCl2 and the self-assembly of a different crystalline phase around the pollutant, which is sequestered and simultaneously quantified by means of a luminescence change. Such a case study might open the way to new-conception strategies to achieve real-time sensing of mercury-containing pollutants in wastewaters and, eventually, pursue their straightforward and cost-effective purification

High interleukin-10 production is associated with low antibody response to influenza vaccination in the elderly

The present study was designed to determine the correlation among dehydroepiandrosterone (DHEA), cortisol plasma levels, and immune functionality at the time of vaccination with antibody response to influenza vaccination in young and old, healthy volunteers. Fifty-two elderly subjects, ages 63-85 years, and 14 young subjects, ages 26-41 years, entered the study. Plasma levels of DHEA and cortisol and in vitro cytokine production in response to lipopolysaccharide (LPS) and phytohaemagglutinin (PHA) by peripheral blood leukocytes were assessed at the time of vaccination, and antibody titer was measured before and 18 days after influenza virus vaccination. Elderly subjects were characterized by an increase in the cortisol:DHEA ratio, mainly as a result of a decrease in DHEA. A decrease in LPS-induced tumor necrosis factor alpha (TNF-alpha), increased PHA-induced interleukin-10 (IL-10) release, and similar PHA-induced interferon-gamma production were observed in elderly subjects compared with young volunteers. Lower antibody titer to influenza A virus was observed in elderly individuals, and the seroconversion factor was found to be correlated inversely with IL-10 production and correlated directly with TNF-alpha production and to a lesser extent, with the plasma level of DHEA. These results suggest that altered cytokine production in elderly subjects at the moment of vaccination can be predictive of a low response to influenza vaccination and warrant the study of strategies to improve protection afforded by the use of vaccine

Preliminary observations of the presence of prednisolone in dairy cattle urine samples

Objectives: In the years 2008-09 the Lombardy region has supported a research with the purpose to detect the presence of drug residues in urine and liver samples collected from cattle at the slaughterhouse. All liver samples resulted to be negative, while the 72% of samples of urine were positive for prednisolone presence. Due to the high number of positive samples it was hypothesized that the stress transport and pre-slaughter conditions could lead to the production of prednisolone in urine. In order to confirm this hypothesis bovine dairy cattle were treated with adrenocorticotropic hormone (ACTH) to simulate stress condition.. Materials and methods: Three Holstein Fresian cows (multiparous, non-pregnant, over 200 days lactating with 29 kg/day mild milk production), were selected. Urine samples were obtained by bladder catheterization before and after the double intramuscular treatment with 1 ml of Sinacthen (Defiant Pharmaceutical) which corresponds to 200 IU of ACTH. Samples were collected at the start of the investigation, after treatment and the time of slaughter (tab. 1). Urine analyses to detect predinisolone presence were performed at the Anabolic and drug residue laboratory of IZSLER with LC-MS/MS system and limit of quantification of 0.58 ng/ml. Results: At the start of the study, all cows were negative for two samples before treatment. In contrast,, all urine samples collected at two and six hours after treatment were positive with prednisolone values between 0.69 and 1,48 ppb. Moreover, with the exception of bovine no. 815 ( sample collected at 42nd hour) no drug was detected in the samples collected 18 and 42 hours after treatment. All samples after transport and slaughter resulted to be positive with prednisolone values between 0.63 and 0,82 ppb. Conclusions: The presence of prednisolone after ACTH treatment seems to suggest the possibility that this molecule could be physiologically produced. Other studies need to be performed in order to confirm this hypothesis and to clarify the metabolic pathwa

Perinatal Parenting Stress, Anxiety, and Depression Outcomes in First-Time Mothers and Fathers: A 3- to 6-Months Postpartum Follow-Up Study

Objective: Although there is an established link between parenting stress, postnatal depression, and anxiety, no study has yet investigated this link in first-time parental couples. The specific aims of this study were 1) to investigate whether there were any differences between first-time fathers’ and mothers’ postnatal parenting stress, anxiety, and depression symptoms and to see their evolution between three and 6 months after their child’s birth; and 2) to explore how each parent’s parenting stress and anxiety levels and the anxiety levels and depressive symptoms of their partners contributed to parental postnatal depression. Method: The sample included 362 parents (181 couples; mothers’ MAge = 35.03, SD = 4.7; fathers’ MAge = 37.9, SD = 5.6) of healthy babies. At three (T1) and 6 months (T2) postpartum, both parents filled out, in a counterbalanced order, the Parenting Stress Index-Short Form, the Edinburgh Postnatal Depression Scale, and the State- Trait Anxiety Inventory. Results: The analyses showed that compared to fathers, mothers reported higher scores on postpartum anxiety, depression, and parenting stress. The scores for all measures for both mothers and fathers decreased from T1 to T2. However, a path analysis suggested that the persistence of both maternal and paternal postnatal depression was directly influenced by the parent’s own levels of anxiety and parenting stress and by the presence of depression in his/her partner. Discussion: This study highlights the relevant impact and effects of both maternal and paternal stress, anxiety, and depression symptoms during the transition to parenthood. Therefore, to provide efficacious, targeted, early interventions, perinatal screening should be directed at both parents

Stability of Mine Car Motion in Curves of Invariable and Variable Radii

We discuss our experiences adapting three recent algorithms for maximum common (connected) subgraph problems to exploit multi-core parallelism. These algorithms do not easily lend themselves to parallel search, as the search trees are extremely irregular, making balanced work distribution hard, and runtimes are very sensitive to value-ordering heuristic behaviour. Nonetheless, our results show that each algorithm can be parallelised successfully, with the threaded algorithms we create being clearly better than the sequential ones. We then look in more detail at the results, and discuss how speedups should be measured for this kind of algorithm. Because of the difficulty in quantifying an average speedup when so-called anomalous speedups (superlinear and sublinear) are common, we propose a new measure called aggregate speedup

Development and Validation of a Novel Skills Training Model for PCNL, an ESUT project

Background and aim: The aim of this study is to validate a totally non biologic training model that combines the use of ultrasound and X ray to train Urologists and Residents in Urology in PerCutaneous NephroLithotripsy (PCNL). Methods: The training pathway was divided into three modules: Module 1, related to the acquisition of basic UltraSound (US) skill on the kidney; Module 2, consisting of correct Nephrostomy placement; and Module 3, in which a complete PCNL was performed on the model. Trainees practiced on the model first on Module 1, than in 2 and in 3. The pathway was repeated at least three times. Afterward, they rated the performance of the model and the improvement gained using a global rating score questionnaire. Results: A total of 150 Urologists took part in this study. Questionnaire outcomes on this training model showed a mean 4.21 (range 1-5) of positive outcome overall. Individual constructive validity showed statistical significance between the first and the last time that trainees practiced on the PCNL model among the three different modules. Statistical significance was also found between residents, fellows and experts scores. Trainees increased their skills during the training modules. Conclusion: This PCNL training model allows for the acquisition of technical knowledge and skills as US basic skill, Nephrostomy placement and entire PCNL procedure. Its structured use could allow a better and safer training pathway to increase the skill in performing a PCNL