A cytological and ultrastructural study on the maturation and germination of oospores of Plasmopara viticola from overwintering vine leaves

Observations on cytological and ultrastructural changes in Plasmopara viticola oospores were carried out during the overwintering period. Three types of oospores were observed. Type I, characterized by a thin inner oospore wall (IOW), large lipid globules and two nuclei, was recovered only in samples collected in October. These oospores were considered to be immature. Maturation occurred during November and involved a noticeable increase in thickness of the IOW, fusion of nuclei, formation of an ooplast and break up of large lipid globules into smaller ones (type II oospores). A few oospores (type III) showed abnormal organization with very large lipid globules and less frequently discernible nuclei. IOW solubilization, dissolution of the ooplast and lipid globules and nuclear division were the first detectable events during oospore germination. Germinating oospores produce a germ tube which was terminated by a sporangium. In its young stage, the sporangium had a thick wall and an unusual multi-layered membrane. During this phase, nuclear divisions took place in the sporangium. While sporangium development progressed, the ribosome density in the cytoplasm decreased and mitochondria, initially roundish with evident cristae, became their usual tubular profile. The plasma membrane had a typical structure and storage organelles, such as finger print vacuoles and lipid globules, became more numerous in the cytoplasm. Larger vacuoles contained the flagella of differentiating zoospores.Observations on cytological and ultrastructural changes in Plasmopara viticola oospores were carried out during the overwintering period. Three types of oospores were observed. Type I, characterized by a thin inner oospore wall (IOW), large lipid globules and two nuclei, was recovered only in samples collected in October. These oospores were considered to be immature. Maturation occurred during November and involved a noticeable increase in thickness of the IOW, fusion of nuclei, formation of an ooplast and break up of large lipid globules into smaller ones (type II oospores). A few oospores (type III) showed abnormal organization with very large lipid globules and less frequently discernible nuclei. IOW solubilization, dissolution of the ooplast and lipid globules and nuclear division were the first detectable events during oospore germination. Germinating oospores produce a germ tube which was terminated by a sporangium. In its young stage, the sporangium had a thick wall and an unusual multi-layered membrane. During this phase, nuclear divisions took place in the sporangium. While sporangium development progressed, the ribosome density in the cytoplasm decreased and mitochondria, initially roundish with evident cristae, became their usual tubular profile. The plasma membrane had a typical structure and storage organelles, such as finger print vacuoles and lipid globules, became more numerous in the cytoplasm. Larger vacuoles contained the flagella of differentiating zoospores

Urban food waste for soil amendment? Analysis and characterisation of waste-based compost for soil fertility management in agroecological horticultural production systems in the city of Rosario, Argentina

Urban and peri-urban lands can be an important source of food production for localised and sustainable food systems, however, their soils can be of poor quality, degraded or damaged by anthropic activities, and little is known about their suitability or safety. This paper aims to contribute to this knowledge gap by assessing the soil remediation capacity and qualities of different types of compost made from urban and peri-urban organic wastes for agroecological food production. Prepared over the course of 2021, and used in 2022 for food growing, five different composts were observed and analysed, in two different farms in the city of Rosario, Argentina. Four raw materials generated largely by local industries were used to make the composts: chicken manure, rumen (cow’s stomachs), brewer’s bagasse (byproducts of the beer industry) and urban leaves collected from the municipality waste collection. These were mixed in different proportions (all reaching the 20–30 C/N ratio, typical of quality compost) to produce viable growing substrates where radishes and lettuces were grown. The aim of the study was to assess the possibility, quality and limitations to use locally available organic inputs for soil fertility management in agroecological farming, in the context of urbanisation and to assess pathways to develop closed-cycle agroecological agriculture at metropolitan level. Natural manure substrates (raw and composted) were analysed, as well as crops grown and fertilised with each of the substrates. The attributes and limiting factors of each substrate and their response to local soil conditions were compared and physicochemical, biochemical, and microbiological analyses were performed, including among others, the study of microbial biomass, biological activity, biophytotoxicity, pH, aerobic heterotrophs, nitrogen fixation, and the presence of antibiotics, agrochemicals and heavy metals. The results of the analyses show that all the composted materials improved the physical, chemical and biological properties. However, in some cases, pollutants were present even after composting. Analysis carried out on the vegetables generally indicate undetectable levels or levels below the admissible limits, demonstrating the filtering capacity of the different composts and the soil

Deformation capacity evaluation for flat slab seismic design

The authors acknowledge the dedicated and careful work carried out by the Associate Editor and Reviewers whose constructive criticism contributed to a very significant improvement of the quality of the paper. Authors wish to dedicate this work to the memory of their co-author Prof. Ion Radu Pascu, UTCB Bucharest, who passed away on June 10, 2021. Publisher Copyright: © 2021, The Author(s).In flat-slab frames, which are typically designed as secondary seismic structures, the shear failure of the slab around the column (punching failure) is typically the governing failure mode which limits the deformation capacity and can potentially lead to a progressive collapse of the structure. Existing rules to predict the capacity of flat slab frames to resist imposed lateral displacements without losing the capability to bear gravity loads have been derived empirically from the results of cyclic tests on thin members. These rules account explicitly only for the ratio between acting gravity loads and resistance against concentric punching shear (so-called Gravity Shear Ratio). Recent rational models to estimate the deformation capacity of flat slabs show that other parameters can play a major role and predict a significant size effect (reduced deformation for thick slabs). In this paper, a closed-form expression to predict the deformation capacity of internal slab-column connections as a function of the main parameters is derived from the same model that has been used to develop the punching shear formulae for the second generation of Eurocode 2 for concrete structures. This expression is compared to an existing database of isolated internal slab-column connections showing fine accuracy and allowing to resolve the shortcomings of existing rules. In addition, the results of a testing programme on a full-scale flat-slab frame with two stories and 12 columns are described. The differences between measured interstorey drifts and local slab rotations influencing their capacity to resist shear forces are presented and discussed. With respect to the observed deformation capacities, similar values are obtained as in the isolated specimens and the predictions are confirmed for the internal columns, but significant differences are observed between internal, edge and corner slab-column connections. The effects of punching shear reinforcement and of integrity reinforcement (required according to Eurocode 2 to prevent progressive collapse after punching) are also discussed.publishersversionpublishe

Ethnographic understandings of ethnically diverse neighbourhoods to inform urban design practice

The aim of this paper is to inform urban design practice through deeper understanding and analysis of the social dynamics of public outdoor space in ethnically diverse neighbourhoods. We hypothesise that findings from ethnographic research can provide a resource that improves cultural literacy and supports social justice in professional practice. The primary method is a meta-synthesis literature review of 24 ethnographic research papers, all of which explore some dimensions of public open space use and values in UK urban contexts characterised by ethnic and racial diversity. We summarise thematic understandings and significance of neighbourhood places of shared activity, parks, spaces of passing-by and of retreat. We evaluate the implications for intercultural social dynamics, exploring the spatial and temporal dimensions of conviviality and racism in public open space. We then argue that it is possible to develop principles for urban design practice informed by this work, and propose four for discussion: maximising straightforward participation, legitimising diversity of activity, designing in micro-retreats of nearby quietness and addressing structural inequalities of open space provision. We conclude that ethnographic research can provide detailed insights into the use of the public realm and also inform a more nuanced understanding of outdoor sociality relevant for an increasingly diverse society. The challenge is two-fold: for ethnographers to become less cautious in engaging with decisions and priorities regarding how cities change, and for urban designers to explicitly embed informed understandings of difference into their broad desire for inclusive public space

Establishing urban gardens on vacant land while considering international good practices: a legal case study from Portugal

There is a gap in most countries’ legal frameworks regarding their ability to connect vacant land and urban gardens. Hence, research is needed to understand how regulation on vacant land might be designed to promote a more sustainable purpose to it. Urban gardens are a type of urban agriculture that could be potentiated by such regulation. The aim of this paper is to show how that can be done through the Municipal Master Plans (MMP) legal and regulatory framework for the Portuguese case, by reviewing worldwide good practices on vacant land restorations for urban sustainable development. The paper comprises a literature review on good practices adopted in different countries regarding vacant lot restoration. The evaluation of good practices is built on the achievement of the three pillars of sustainability. Five Portuguese MMP were used, as empirical data, to support the design of a new legal and regulatory framework. The goal is to enhance the sustainable destination of vacant land by converting it into urban gardens. The analysis of these MMPs demonstrated that they disregard urban gardens as a tool to promote urban sustainability in spite of global trends to make urban territorial planning and management instruments greener. An additional outcome of this paper is to categorise different types of vacant land in the five municipalities under analysis according to their suitability for urban garden conversion. The design of the legal framework enhancing the conversion of vacant land into urban garden will contribute to the 2030 international agenda goals’ achievement. The proposal would create an innovative legal framework in the case of Portugal that could be replicated by other countries.info:eu-repo/semantics/acceptedVersio

Physical activity levels across COVID-19 outbreak in youngsters of Northwestern Lombardy

BACKGROUND: Italy early experienced one of the most suffering impact of the COVID-19 outbreak in terms of number of cases and death toll. Progressively, more compelling national restrictions hardened citizens' lifestyle and habits, including limiting mobility and outdoor physical activity (PA ). In a second phase, people were allowed to perform outdoor activities close to their houses and thereafter motor or sports activity were gradually reintroduced. These drastic changes raised the question on how to cope and exploit the residual oppor tunities of PA under circumstances of home confinement. METHODS: International Physical Activity Questionnaires were administered to 1568 youngsters from North-western Italian high schools, before, during, and after lockdown enacted by Italian Government to contrast the COVID-19 pandemic. RESULTS: Student's PA levels were significantly different before (1676.37±20.6 MET-min/week) and after (1774.50±33.93 MET-min/week) the governmental restrictions (TIME effect: F=3.49; ηp2=0.005 P=0.03). There was a significant TIME∗CATEGORY interaction effect (F=8.37; ηp2=0.021; P<0.001). In particular, only highly active students (>2520 MET-min/week) increased their PA during (3467.48±55.85 MET-min/ week) and after (3515.73±65.75 MET-min/week) the lockdown measures with respect to their baseline levels (3151.43±42.41 MET-min/week). CONCLUSIONS: Lockdown measures, including isolation, impacted negatively on the PA levels of the already inactive or moderately active young population. Government actions should enhance strategies to control physical inactivity during pandemics like COVID-19

End support connection of precast roof elements by bolted steel angles

Steel angles are extensively used to connect concrete floor/roof elements to the supporting beam in typical dry-assembled precast frame structures widely diffused in Europe and other parts of the world. These connections allow for relative rotation of the floor element in its vertical plane and restrains their relative displacement, avoiding possible loss of support and consequent fall of the floor element when the structure is subjected to lateral load. The diaphragm behaviour of the precast decks relies on these floor-to-beam connections. Their post-addition to unconnected floor-to-beam joints of existing buildings is a typical seismic retrofit intervention. All these applications are often made without an adequate information about the main structural parameters of the connections, due to lack of experimental or theoretical knowledge. An experimental campaign has been performed at Politecnico di Milano within the framework of the Safecast and ReLUIS research projects with the scope of characterising the mechanical behaviour of post-inserted floor-to-beam connections made with hot-rolled angles, cold-formed angles and welded sockets in the direction parallel to the floor element. The results of monotonic local tests on connectors and on the bolted connection with the floor rib and of cyclic and monotonic sub-assembly tests allowed to determine the main structural parameters of the joints, including elastic stiffness, strength, displacement capacity and hysteretic shape

Improvement of auditory brainstem responses after treatment with zidovudine in a child with AIDS

A 6 1/2-month-old boy with acquired immunodeficiency syndrome was treated with zidovudine for 12 months. He experienced a marked improvement in clinical and neurologic status. Auditory brainstem responses were recorded before, at 6 months, and after 12 months of therapy; interpeak latency I-V, which was initially delayed, demonstrated progressive shortening that was greater than could be attributed to maturation alone. Auditory brainstem response improvement after zidovudine therapy has not been reported previously

Etiology of acute otitis media in human immunodeficiency virus-infected children

Acute otitis media (AOM) is one of the most common infections that are implicated as significant contributors to morbidity in HIV-infected children. To establish the optimal antibiotic therapy tympanocentesis is indicated as the first line diagnostic procedure, because unusual pathogens may play a role in advanced stages of deficient humoral or cellular immunity

Acute otitis media in human immunodeficiency virus-infected children

To evaluate the occurrence and outcome of acute otitis media (AOM) in human immunodeficiency virus (HIV)-infected children, a prospective comparative cohort study was performed. Twenty-seven HIV-infected children were individually matched with paired control subjects and followed up for 543 months (mean 19.4 +/- 11). Data collected were evaluated considering HIV-infected children both as a whole and as P1 and P2 patients according to Centers for Disease Control classification. During the observation period, 46 episodes of AOM were diagnosed in 15 HIV patients and 22 in 16 control children: 11 P1 had 27 AOM episodes vs 17 in 13 control children; 6 P2 had 19 AOM episodes vs 5 in 4 control children. Human immunodeficiency virus infection does not seem to modify the occurrence of AOM. Recurrent AOM (3 or more episodes in 6 months) was, however, significantly more common in P2 children. Amoxicillin, to which the bacteria isolated in P2 children were sensitive in vitro, cured 33 of 46 episodes in HIV-infected children compared with 20 of 22 in control children. Cure rate was similar in P1 children compared with control children but was significantly lower in P2 versus control children (47.3% vs 100%). Reasons for higher occurrence of failures in P2 children remain to be investigated