Sublinearly space bounded iterative arrays

Iterative arrays (IAs) are a, parallel computational model with a sequential processing of the input. They are one-dimensional arrays of interacting identical deterministic finite automata. In this note, realtime-lAs with sublinear space bounds are used to accept formal languages. The existence of a proper hierarchy of space complexity classes between logarithmic anel linear space bounds is proved. Furthermore, an optimal spacc lower bound for non-regular language recognition is shown. Key words: Iterative arrays, cellular automata, space bounded computations, decidability questions, formal languages, theory of computatio

Latvian Quantum Finite State Automata for Unary Languages

We design Latvian quantum finite state automata (LQFAs for short) recognizing unary regular languages with isolated cut point 1/2. From an architectural point of view, we combine two LQFAs recognizing with isolated cut point, respectively, the finite part and the ultimately periodic part of any given unary regular language L. In both modules, we use a component addressed in the literature and here suitably adapted to the unary case, to discriminate strings on the basis of their length. The number of basis states and the isolation around the cut point of the resulting LQFA for L exponentially depends on the size of the minimal deterministic finite state automaton for L.Comment: In Proceedings NCMA 2023, arXiv:2309.0733

Converting two-way nondeterministic unary automata into simpler automata

AbstractWe show that, on inputs of length exceeding 5n2, any n-state unary two-way nondeterministic finite automaton (2nfa) can be simulated by a (2n+2)-state quasi-sweeping 2nfa. Such a result, besides providing a “normal form” for 2nfa's, enables us to get a subexponential simulation of unary 2nfa's by two-way deterministic finite automata (2dfa's). In fact, we prove that any n-state unary 2nfa can be simulated by a sweeping 2dfa with O(n⌈log2(n+1)+3⌉) states

FTIR spectral signatures of mouse antral oocytes: Molecular markers of oocyte maturation and developmental competence

AbstractMammalian antral oocytes with a Hoescht-positive DNA ring around the nucleolus (SN) are able to resume meiosis and to fully support the embryonic development, while oocytes with a non-surrounded nucleolus (NSN) cannot. Here, we applied FTIR microspectroscopy to characterize single SN and NSN mouse oocytes in order to try to elucidate some aspects of the mechanisms behind the different chromatin organization that impairs the full development of NSN oocyte-derived embryos. To this aim, oocytes were measured at three different stages of their maturation: just after isolation and classification as SN and NSN oocytes (time 0); after 10h of in vitro maturation, i.e. at the completion of the metaphase I (time 1); and after 20h of in vitro maturation, i.e. at the completion of the metaphase II (time 2). Significant spectral differences in the lipid (3050–2800cm−1) and protein (1700–1600cm−1) absorption regions were found between the two types of oocytes and among the different stages of maturation within the same oocyte type. Moreover, dramatic changes in nucleic acid content, concerning mainly the extent of transcription and polyadenylation, were detected in particular between 1000 and 800cm−1. The use of the multivariate principal component–linear discriminant analysis (PCA–LDA) enabled us to identify the maturation stage in which the separation between the two types of oocytes took place, finding as the most discriminating wavenumbers those associated to transcriptional activity and polyadenylation, in agreement with the visual analysis of the spectral data

Dietary Folate, Alcohol Consumption, and Risk of Ovarian Cancer in an Italian Case-Control Study

An increasing number of studies are focusing on the potential association between dietary folate intake and risk of various cancers (1), particularly of the colorectum and breast (2, 3). A low folate status can induce misincorporation of uracil into DNA, leading to chromosome breaks in humans and hence increasing cancer risk (4). Alcohol may increase folate requirements in the body and cause relative folate deficiencies (2). Although several findings on the relation between folate intake and ovarian cancer risk are inconsistent (5-9), recent results from two prospective studies, including 266 and 147 incident cases of epithelial ovarian cancer, have suggested an interaction of folate and alcohol in ovarian carcinogenesis [i.e., folate would be inversely related to ovarian cancer risk in alcohol drinkers (5, 6), and alcohol in those with high folate intake (7)]. With the aim to provide further data on the issue, we assessed the relation between dietary folate, alcohol consumption, and ovarian cancer risk in a multicentric case-control study conducted in Italy (10)

FT-IR spectroscopy supported by PCA–LDA analysis for the study of embryonic stem cell differentiation

As recently pointed out in the literature, Fourier transform infrared (FT-IR) spectroscopy is emerging as a powerful tool in stem cell research. In this work we characterizedin situby FT-IR microspectroscopy the differentiation of murine embryonic stem cells (ES) to monitor possible changes in the cell macromolecular content during the early stages of differentiation. Undifferentiated and differentiating cells at 4, 7, 9 and 14 days were measured. Data were analyzed by the principal component and subsequent linear discriminant analyses (PCA–LDA) that enabled us to segregate ES cell spectra into well separate clusters and to identify the most significant spectral changes. Important changes in the lipid (3050–2800 cm–1), protein (1700–1600 cm–1) and in the nucleic acid (1050–850 cm–1) absorption regions were observed between days 4 to 7 of differentiation, indicating the appearance – at day 7 – of the new phenotype into cardiomyocyte precursors. Also the presence of DNA/RNA hybrid bands (954 cm–1and 899 cm–1) suggests that the transcriptional switch of the genome started at this stage of differentiation. Particularly noteworthy, we suggest that the 2936 cm–1shoulder we observed could reflect methyl group vibrations thus allowing the detection of variations in methylation levels of the stem cell during differentiation. These infrared results were found to be in agreement with the biochemical characterization of these differentiating cells, underlying the great potential of FT-IR spectroscopy in stem cell research

FT-IR spectroscopy supported by PCA–LDA analysis for the study of embryonic stem cell differentiation

As recently pointed out in the literature, Fourier transform infrared (FT-IR) spectroscopy is emerging as a powerful tool in stem cell research. In this work we characterizedin situby FT-IR microspectroscopy the differentiation of murine embryonic stem cells (ES) to monitor possible changes in the cell macromolecular content during the early stages of differentiation. Undifferentiated and differentiating cells at 4, 7, 9 and 14 days were measured. Data were analyzed by the principal component and subsequent linear discriminant analyses (PCA–LDA) that enabled us to segregate ES cell spectra into well separate clusters and to identify the most significant spectral changes. Important changes in the lipid (3050–2800 cm–1), protein (1700–1600 cm–1) and in the nucleic acid (1050–850 cm–1) absorption regions were observed between days 4 to 7 of differentiation, indicating the appearance – at day 7 – of the new phenotype into cardiomyocyte precursors. Also the presence of DNA/RNA hybrid bands (954 cm–1and 899 cm–1) suggests that the transcriptional switch of the genome started at this stage of differentiation. Particularly noteworthy, we suggest that the 2936 cm–1shoulder we observed could reflect methyl group vibrations thus allowing the detection of variations in methylation levels of the stem cell during differentiation. These infrared results were found to be in agreement with the biochemical characterization of these differentiating cells, underlying the great potential of FT-IR spectroscopy in stem cell research

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Multi-messenger Observations of a Binary Neutron Star Merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ∼ 1.7 {{s}} with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of {40}-8+8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 {M}ȯ . An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ∼ 40 {{Mpc}}) less than 11 hours after the merger by the One-Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ∼10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ∼ 9 and ∼ 16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC 4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta.</p