207 research outputs found
Regulation of globin gene expression: boxes and borders
The experimental work presented in this thesis pertains to the regulation of gene expression
and focuses on the regulation of the B globin genes. The expression of the globin genes is
restricted to the erythropoietic tissue and is regulated during development. Therefore the study
of globin gene expression can yield valuable insights in how organisms regulate their genes in
a coordinated tissue and developmental manner.
Two main issues will be addressed in the chapters of this thesis. The first concerns the
mechanism by which a transcriptionally competent domain is formed in the chromosomal
environment. This topic is the subject of Chapter 2. Once transcriptionally competent domains
are formed, gene transcription can take place and it is orchestrated by factors that interact
specifically with the regulatory elements of the gene itself. This interaction determines tissue
specificity and developmental regulation of a gene. The second issue addressed concerns the
transcriptional regulation of the ~ globin gene via their CCAAT boxes studied through NFE6,
a factor that binds to these elements (Chapters 3 and 4). NF-E6 interaction with its target
sequence participates in the change in globin gene expression concomitant with the
progressive changes that occur during the development of an embryo to a fetus
Analysis of an Integrated Agro-waste Gasification and 120 kW SOFC CHP System: Modeling and Experimental Investigation
Abstract Renewable sources of hydrogen are of major interest in the context of energy production through fuel cells. The technical feasibility of CHP system composed by orange peels steam/air gasification unit coupled with a solid oxide fuel cell (SOFC) was investigated in this study. To this purpose, a zero-dimensional process simulation model of the CHP system using Aspen Plus was developed. Mathematical model was experimentally validated in a lab scale apparatus. Moreover, optimal operative conditions and integration options were investigated, as well as the system maximum theoretical overall efficiency. Results showed that in order to obtain 120 kW of DC power from the specific SOFC, 65 kg/h of biomass with 20% of moisture and 173 kg/h of raw biomass with 70% of water needed to be fed in the CHP system. It was theoretically proved that 120 kW of DC power and 135 kW of heat could be produced from SOFC unit at the selected operative conditions, with a net CHP maximum efficiency equal to 74%
The Red-throated pipit Anthus cervinus is a regular wintering in Sicily
We present a review of the phenology of the Red-throated Pipit Anthus cervinus and its wintering status in Sicily. We collected and analysed 91 different records related to a total of 280 indi-viduals. Data were collected both through direct observations on the field and by consulting recent literature and ornithological databases. The species has been regularly found overwintering during the last 11 winters (December 2012-January 2023), with the only exception of the winter of 2014/2015, likely due to the lack of coverage and targeted research, with an estimated population of 180-190 individuals. The average value is 3.07 individuals/records observed in 18 different loca-tions related to four Sicilian provinces (Caltanissetta, Catania, Sira-cusa, Trapani), mainly near wetlands and, more specifically, in Medi-terranean and thermo-Atlantic halophytic meadows and Mediterranean salt meadows. The number of wintering sites in the recent years appears to be increasing
Visual perceptual learning is effective in the illusory far but not in the near space
Visual shape discrimination is faster for objects close to the body, in the peripersonal space (PPS), compared to objects far from the body. Visual processing enhancement in PPS occurs also when perceived depth is based on 2D pictorial cues. This advantage has been observed from relatively low-level (detection, size, orientation) to high-level visual features (face processing). While multisensory association also displays proximal advantages, whether PPS influences visual perceptual learning remains unclear. Here, we investigated whether perceptual learning effects vary according to the distance of visual stimuli (near or far) from the observer, illusorily induced by leveraging the Ponzo illusion. Participants performed a visual search task in which they reported whether a specific target object orientation (e.g., triangle pointing downward) was present among distractors. Performance was assessed before and after practising the visual search task (30 minutes/day for 5 days) at either the close (near group) or far (far group) distance. Results showed that participants that performed the training in the near space did not improve. By contrast, participants that performed the training in the far space showed an improvement in the visual search task in both the far and near spaces. We suggest that such improvement following the far training is due to a greater deployment of attention in the far space, which could make the learning more effective and generalize across spaces
THE ENVIRONMENTAL IMPACT OF POWER LINES ON BIRDS IN SICILY
Electrocution is a serious conservation problem worldwide for a large number of bird species
(BEVANGER, 1994, 1998; BIRDLIFE INTERNATIONAL, 2004; PRINSEN et al., 2011). Due to its wide
extension, it is necessary to seek methods that optimize the identification of the most dangerous pylons
(JANSS and FERRER, 2001; MANOSA, 2001), lines and the highest risk areas (TINTÓ et al., 2010; GUIL et
al., 2011). Actually, the data on bird mortality caused by electrocution and collision in Sicily are
deficient, however, a preliminary study suggests that the White Stork (Ciconia ciconia L., 1758) is one
of the most threatened species inside two Special Protection Areas (SPA) (ZAFARANA and BARBERA,
2016). The project C.L.E.S.A. aims at making a complete checklist of the species at risk, collecting
information from published articles and personal reports. Unpublished data were collected through a
request for information widely circulated among professional and dabbler ornithologists, local sections
of bird conservation ONG and wildlife services. A standard monitoring method was used to collect data,
monthly during the entire sampling period. First, we selected different transects randomly, and,
subsequently, we counted and removed all the birds found dead. A total of 152 cases were collected from
1996 to 2017, of which 85 caused by electrocution and 67 by collision. The 55.5% of the founded species
are considered as “Birds of Community Importance” (included in Annex I of the Council Directive
2009/147/EC on the conservation of wild birds). C. ciconia is the most species killed by electrocution
and Phoenicopterus roseus Pallas, 1811 by collision. These preliminary results suggest that this problem,
as well as having serious consequences in terms of conservation, could has serious economic
repercussions for human societies, as power failures, loss of revenue, necessity of repairs infrastructures
and cost of legal compliance (LEHMAN et al., 2007). The monitoring activities of the C.L.E.S.A.
volunteers have the purpose of implementing direct conservation actions for endangered species. The
synergy between power companies and C.L.E.S.A. will be basic to adopt the measures suggested by the
Conference of the Parties in Resolution 7.4 "Electrocution of migratory birds" (BONN, 2002) and the
current management plans for SPAs. This partnership will improve the effective field actions in Sicily
The human beta-globin locus control region confers an early embryonic erythroid-specific expression pattern to a basic promoter driving the bacterial lacZ gene
The beta-globin locus control region (LCR) is contained on a 20 kb DNA
fragment and is characterized by the presence of five DNaseI
hypersensitive sites in erythroid cells, termed 5'HS1-5. A fully active
6.5 kb version of the LCR, called the muLCR, has been described.
Expression of the beta-like globin genes is absolutely dependent on the
presence of the LCR. The developmental expression pattern of the genes in
the cluster is achieved through competition of the promoters for the
activating function of the LCR. Transgenic mice experiments suggest that
subtle changes in the transcription factor environment lead to the
successive silencing of the embryonic epsilon-globin and fetal
gamma-globin promoters, resulting in the almost exclusive transcription of
the beta-globin gene in adult erythropoiesis. In this paper, we have asked
the question whether the LCR and its individual hypersensitive sites
5'HS1-4 can activate a basic promoter in the absence of any other globin
sequences. We have employed a minimal promoter derived from the mouse
Hsp68 gene driving the bacterial beta-galactosidase (lacZ) gene. The
results show that the muLCR and 5'HS3 direct erythroid-specific, embryonic
expression of this construct, while 5'HS1, 5'HS2 and 5'HS4 are inactive at
any stage of development. Expression of the muLCR and 5'HS3 transgenes is
repressed during fetal stages of development. The transgenes are in an
inactive chromatin conformation and the lacZ gene is not transcribed, as
shown by in situ hybridization. These data are compatible with the
hypothesis that the LCR requires the presence of an active promoter to
adopt an open chromatin conformation and with models proposing progressive
heterochromatization during embryogenesis. The results suggest that the
presence of a beta-globin gene is required for LCR function as conditions
become more stringent during development
Coamplification of DAD-R, SOX5, and EKI1 in human testicular seminomas, with specific overexpression of DAD-R, correlates with reduced levels of apoptosis and earlier clinical manifestation
Seminomas and nonseminomas represent the invasive stages of testicular
(TGCTs) of adolescents and adults. Although TGCTs are characterized by
extra copies of the short arm of chromosome 12, the genetic basis for gain
of 12p in the pathogenesis of this cancer is not yet understood. We have
demonstrated that gain of 12p is related to invasive growth and that
amplification of specific 12p sequences, i.e., 12p11.2-p12.1, correlates
with reduced apoptosis in the tumors. Here we show that three known genes
map within the newly determined shortest region of overlap of
amplification (SROA): DAD-R, SOX5, and EKI1. Whereas EKI1 maps close to
the telomeric region of the SROA, DAD-R is the first gene at the
centromeric region within the 12p amplicon. Although all three genes are
amplified to the same level within the SROA, expression of DAD-R is
significantly up-regulated in seminomas with the restricted 12p
amplification compared with seminomas without this amplicon. DAD-R is also
highly expressed in nonseminomas of various histologies and derived cell
lines, both lacking such amplification. This finding is of particular
interest because seminomas with the restricted 12p amplification and
nonseminomas are manifested clinically in the third decade of life and
show a low degree of apoptosis. In contrast, seminomas lacking a
restricted 12p amplification, showing significantly lower levels of DAD-R
with pronounced apoptosis, manifest clinically in the fourth decade of
life. A low level of DAD-R expression is also observed in normal
testicular parenchyma and in parenchyma containing the precursor cells of
this cancer, i.e., carcinoma in situ. Therefore, elevated DAD-R expression
in seminomas and nonseminomas correlates with invasive growth and a
reduced level of apoptosis associated with an earlier clinical
presentation. These data implicate DAD-R as a candidate gene responsible
in part for the pathological effects resulting from gain of 12p sequences
in TGCTs. In addition, our results also imply differences in expression
regulation of DAD-R between seminomas and nonseminomas
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