Meiotic double strand breaks repair in sexually reproducing eukaryotes: We are not all equal.

The defining event of meiosis is prophase-I, during which the maternal and paternal chromosome find each other in the nucleus, pair, and align in a process called “synapses of the homologues”. Their faithful segregation during the first meiotic division (MI) requires meiotic recombination and in particular at least one crossing over (CO) per pair of homologous chromosomes. COs are needed, not only to generate diversity within a population, but (along with sister chromatids cohesion) to form the chiasmata that are the physical connection between the homologues that ensures their faithful segregation at metaphase-I. Our understanding of recombination in higher eukaryotes has comes from studies in model organisms such as yeasts, flies and worms. Although there are clear differences among organisms, most of the genes and proteins that are required in these processes are conserved and have orthologues in mammals. However, their null mutations in mice (Mus musculus) do not always display the same phenotype as in lower eukaryotes, indicating that along with the increased complexity of the genome, same genes have acquired new or partially overlapping functions. In this review we will focus on the main genes and protein products which are required for meiotic recombination, comparing the simple metazoan C. elegans and the mouse, underlying divergences and similarities between these organism

Seismic reflection data in the Umbria Marche Region: limits and capabilities to unravel the subsurface structure in a seismically active area

Before seismic data were made available, the subsurface setting of the Umbria-Marche area was mainly derived from the extrapolation of surface data and from models resulting from analogies with other mountain chains around the world. During the ‘90s industrial seismic data availability considerably increased, allowing the definition of new, previously unknown features. Beside the industrial seismic data availability, a deep crustal, near vertical seismic section trending E-W was acquired (CROP-03) across the Italian peninsula from the Tyrrhenian to the Adriatic coast. The subsurface data defined the compressional deformation style (thin- Vs thick- skinned) and the extensional deformation style. A set of east-dipping low-angle-normal faults, which dissect the previous compressional structures and which are the dominant features controlling the extension of the Apennines were recognised. The subsequent application of the seismic data interpretation to seismotectonic issues, defined in more detail the subsurface geometries of the active faults and the relationships between upper crust structure and seismicity

Source Code Classification for Energy Efficiency in Parallel Ultra Low-Power Microcontrollers

The analysis of source code through machine learning techniques is an increasingly explored research topic aiming at increasing smartness in the software toolchain to exploit modern architectures in the best possible way. In the case of low-power, parallel embedded architectures, this means finding the configuration, for instance in terms of the number of cores, leading to minimum energy consumption. Depending on the kernel to be executed, the energy optimal scaling configuration is not trivial. While recent work has focused on general-purpose systems to learn and predict the best execution target in terms of the execution time of a snippet of code or kernel (e.g. offload OpenCL kernel on multicore CPU or GPU), in this work we focus on static compile-time features to assess if they can be successfully used to predict the minimum energy configuration on PULP, an ultra-low-power architecture featuring an on-chip cluster of RISC-V processors. Experiments show that using machine learning models on the source code to select the best energy scaling configuration automatically is viable and has the potential to be used in the context of automatic system configuration for energy minimisation

Male infertility due to germ cell apoptosis in mice lacking the thiamin carrier, Tht1. A new insight into the critical role of thiamin in spermatogenesis.

A mouse model of thiamin-responsive megaloblastic anemia (diabetes mellitus, deafness, megaloblastic anemia) lacking functional Slc19a2 has been generated and unexpectedly found to have a male-specific sterility phenotype. We describe here the characterization of the testis-specific effects of absence of the high-affinity thiamin transporter, Tht1. Null males were found to have hypoplastic testes secondary to germ cell depletion. Morphologic and expression analysis revealed that under conditions of standard thiamin intake, tissues affected in the syndrome (pancreatic beta-cell, hematopoietic cells, auditory nerve) maintained normal function but pachytene stage spermatocytes underwent apoptosis. Under conditions of thiamin challenge, the apoptotic cell loss extended to earlier stages of germ cells but spared Sertoli cells and Leydig cells. Injection of high-dose thiamin was effective in reversing the spermatogenic failure, suggesting that the absence of the thiamin carrier could be overcome by diffusion-mediated transport at supranormal thiamin concentrations. These observations demonstrated that male germ cells, particularly those with high thiamin transporter expression beyond the blood-testis barrier, were more susceptible to apoptosis triggered by intracellular thiamin deficiency than any other tissue type. The findings described here highlight an unexpected and critical role for thiamin transport and metabolism in spermatogenesis

Structural comparison of a 15 residue peptide from the V3 loop of HIV-1IIIb and an O-glycosylated analogue

AbstractAs part of a program to study the effect of glycosylation on the three-dimensional structures of HIV-1IIIB V3 peptide constructs, we have examined the solution structures of a 15 residue peptide (RIQRGPGRAFVTIGK, P18IIIB), originally mapped as an epitope recognized by CD8+ Dd class I MHC-restricted murine cytotoxic T-lymphocytes (CTL), and an analogue (P18IIIB-g), O-glycosylated with an α-galactosamine on Thr-12, using NMR, circular dichroism and molecular modeling methods. Our studies show that the peptides sample mainly random conformations in aqueous solution near 25°C and become more ordered by the addition of trifluoroethanol. Upon decreasing the temperature to 5°C, a reverse turn is formed around the immunodominant tip (G5−R8). Glycosylation on T12 ‘tightens’ the turn slightly as suggested by NOE and CD analysis. In addition, the sugar has a defined conformation with respect to the peptide backbone and influences the local peptide conformation. These data suggest that simple glycosylation may influence the conformational equilibrium of a V3 peptide which contains a domain critical for antibody recognition and virus neutralization. We also show that the ability of cytotoxic T-lymphocytes (CTL) to lyse tumor cells presenting P18IIIB was completely abrogated by threonine glycosylation

Benchmarking a many-core neuromorphic platform with an MPI-based DNA sequence matching algorithm

SpiNNaker is a neuromorphic globally asynchronous locally synchronous (GALS)multi-core architecture designed for simulating a spiking neural network (SNN) in real-time. Several studies have shown that neuromorphic platforms allow flexible and efficient simulations of SNN by exploiting the efficient communication infrastructure optimised for transmitting small packets across the many cores of the platform. However, the effectiveness of neuromorphic platforms in executing massively parallel general-purpose algorithms, while promising, is still to be explored. In this paper, we present an implementation of a parallel DNA sequence matching algorithm implemented by using the MPI programming paradigm ported to the SpiNNaker platform. In our implementation, all cores available in the board are configured for executing in parallel an optimised version of the Boyer-Moore (BM) algorithm. Exploiting this application, we benchmarked the SpiNNaker platform in terms of scalability and synchronisation latency. Experimental results indicate that the SpiNNaker parallel architecture allows a linear performance increase with the number of used cores and shows better scalability compared to a general-purpose multi-core computing platform

Women in geosciences within the Italian University system in the last 20 years

Abstract. This work aims at providing an updated scenario on the underrepresentation of women in the Italian university system in the area of geosciences in the last two decades. The retrieved official data on permanent full and associate professors in the 19-years considered highlight some positive trends: an increase in the number of female full professors from 9.0 % to 18.5 % and in female associate professors from 23.6 % to 28.9 %. However, although the number of female full professors almost doubled in this period, such increase still represents an excessively slow trend. Slightly better is the trend related to associate professors. The picture portrayed for non-permanent researchers, called RTD-b, as introduced by the Italian Law no. 240/2010 (essentially tenure-track associate professor position), instead raises strong concerns for the future seen that the female percentage is just 26 %, thus exhibiting a significant gender imbalance. This is even more significant if we consider that the student population in geosciences shows a gender imbalance of about 37 %, no gender gap at PhD level and a relatively high Glass Ceiling Index (GCI) during the career progression of women. An analysis of the geographical distribution of female researchers in geosciences has evidenced that, although the percentages of women are comparable, the GCI calculated in Southern Italy has been alarmingly high in the last 2–3 years and is divergent from the decrease observed in Northern and Central Italy. The work also analyses the gender balance over different areas of geosciences, showing that in Paleontology and Paleoecology the gap is inverted with more female than male professors, both at full and associate professor level, whereas the gap is almost closed in Mineralogy for associate professors, far though from being balanced for full professors. All remaining geological disciplines suffer a gender imbalance. Further analysis carried out in this work unveils that the number of female full professor is low (<10 %) both at national and regional level in the 2000–2009 decade, consistent with a GCI higher than 2.5–3. From 2010 to 2013, likely in response to the Italian Law no. 240 of 2010, an important progressive increase, associated with a decrease of GCI, is visible. However, from 2014 to 2019 the percentage remains constant (∼20 %) with the exception of Southern Italy, which displays a return to lower values (<15 %). Finally, an international comparison with countries like Germany and the USA definitively indicates that the Italian university system is more equal in terms of gender balance. Even if some significant and positive steps have been carried out in the Italian university system, still much effort is required to fight a general and crucial problem which is the gender balance issue. Results could be achieved promoting work-life balance policies that better reconcile family and work, stimulating a reorganization of the work system still currently set on the male model but, and more importantly, changing the prevailing patriarchal mentality. The Italian university system has already a great example to follow: the zero-pay gap. This is possibly the only system worldwide where male and female professors earn the same identical salary, compared to the salary gap of between 15 % and 30 % of countries richer than Italy, and must be the target to reach, in the near future, for gender balance

Pyomyositis associated with abscess formation caused by streptococcus pneumoniae in children: a case report and review of literature

Background: Pyomyositis is an unusual bacterial infection but potential severe in children. Staphylococcus Aureus is the main caused of this disease (70–90%), following by Streptococcus Pyogenes (4–16%). Streptococcus Pneumoniae rarely caused invasive muscular infections. We describe a case of pyomyositis caused by Streptococcus Pneumonia in an adolescent 12-year-old female. Case presentation: I.L. referred to our hospital for high fever associated with right hip and abdominal pain. The blood exams showed increase of leukocytes with prevalence of neutrophils with high level of inflammatory markers (CRP 46,17&nbsp;mg/dl; Procalcitonin 25,8 ng/ml). The abdomen ultrasonography was unremarkable. The CT and MRI of the abdomen and right hip revealed pyomyositis of the iliopsoas, piriformis and internal shutter associated with collection of pus between the muscular planes (Fig.&nbsp;1). The patient was admitted to our paediatric care unit, and she was initially treatment with intravenous Ceftriaxone (100&nbsp;mg/kg/day) and Vancomycin (60&nbsp;mg/kg/day). On day 2, a pansensitive Streptococcus Pneumoniae was isolated from the blood culture, and the antibiotic treatment was changed to only IV Ceftriaxone. She was successively treated with IV Ceftriaxone for 3 weeks, then continued with oral Amoxicillin for a total of 6 weeks of therapy. The follow up showed a complete resolution of the pyomyositis and psoas abscess after 2 months. Conclusion: Pyomyositis associate with abscess is a rare and very dangerous disease in children. The clinical presentation can mimic symptoms of other pathologies like osteomyelitis or septic arthritis, so many times is hard to identify. The main risk factors include story of recent trauma and immunodeficiency, not present in our case report. The therapy involves the antibiotics and, if possible, abscess drainage. In literature there is much discussion about duration of antibiotic therapy