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1.
Theor Popul Biol ; 158: 60-75, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38641140

ABSTRACT

We consider the Moran model of population genetics with two types, mutation, and selection, and investigate the line of descent of a randomly-sampled individual from a contemporary population. We trace this ancestral line back into the distant past, far beyond the most recent common ancestor of the population (thus connecting population genetics to phylogeny), and analyse the mutation process along this line. To this end, we use the pruned lookdown ancestral selection graph (Lenz et al., 2015), which consists of a set of potential ancestors of the sampled individual at any given time. Relative to the neutral case (that is, without selection), we obtain a general bias towards the beneficial type, an increase in the beneficial mutation rate, and a decrease in the deleterious mutation rate. This sheds new light on previous analytical results. We discuss our findings in the light of a well-known observation at the interface of phylogeny and population genetics, namely, the difference in the mutation rates (or, more precisely, mutation fluxes) estimated via phylogenetic methods relative to those observed in pedigree studies.

2.
J Ovarian Res ; 17(1): 63, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38491534

ABSTRACT

BACKGROUND: Artificial Intelligence entails the application of computer algorithms to the huge and heterogeneous amount of morphodynamic data produced by Time-Lapse Technology. In this context, Machine Learning (ML) methods were developed in order to assist embryologists with automatized and objective predictive models able to standardize human embryo assessment. In this study, we aimed at developing a novel ML-based strategy to identify relevant patterns associated with the prediction of blastocyst development stage on day 5. METHODS: We retrospectively analysed the morphokinetics of 575 embryos obtained from 80 women who underwent IVF at our Unit. Embryo morphokinetics was registered using the Geri plus® time-lapse system. Overall, 30 clinical, morphological and morphokinetic variables related to women and embryos were recorded and combined. Some embryos reached the expanded blastocyst stage on day 5 (BL Group, n = 210), some others did not (nBL Group, n = 365). RESULTS: The novel EmbryoMLSelection framework was developed following four-steps: Feature Selection, Rules Extraction, Rules Selection and Rules Evaluation. Six rules composed by a combination of 8 variables were finally selected, and provided a predictive power described by an AUC of 0.84 and an accuracy of 81%. CONCLUSIONS: We provided herein a new feature-signature able to identify with an high performance embryos with the best developmental competence to reach the expanded blastocyst stage on day 5. Clear and clinically relevant cut-offs were identified for each considered variable, providing an objective tool for early embryo developmental assessment.


Subject(s)
Artificial Intelligence , Embryonic Development , Female , Humans , Retrospective Studies , Blastocyst , Machine Learning , Embryo Culture Techniques/methods , Time-Lapse Imaging/methods
3.
Phys Rev Lett ; 124(21): 211601, 2020 May 29.
Article in English | MEDLINE | ID: mdl-32530699

ABSTRACT

We present the analytic form of the two-loop four-graviton scattering amplitudes in Einstein gravity. To remove ultraviolet divergences we include counterterms quadratic and cubic in the Riemann curvature tensor. The two-loop numerical unitarity approach is used to deal with the challenging momentum dependence of the interactions. We exploit the algebraic properties of the integrand of the amplitude in order to reduce it to a minimal basis of Feynman integrals. Analytic expressions are obtained from numerical evaluations of the amplitude. Finally, we show that four-graviton scattering observables depend on fewer couplings than naïvely expected.

4.
Phys Rev Lett ; 122(8): 082002, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30932613

ABSTRACT

We present the analytic form of the planar two-loop five-gluon scattering amplitudes in QCD for a complete set of independent helicity configurations of external gluons. These include the first analytic results for five-point two-loop amplitudes relevant for the computation of next-to-next-to-leading-order QCD corrections at hadron colliders. The results were obtained by reconstructing analytic expressions from numerical evaluations. The complexity of the computation is reduced by exploiting physical and analytical properties of the amplitudes, employing a minimal basis of so-called pentagon functions that have recently been classified.

5.
Phys Rev Lett ; 119(14): 142001, 2017 Oct 06.
Article in English | MEDLINE | ID: mdl-29053299

ABSTRACT

We present the first numerical computation of two-loop amplitudes based on the unitarity method. As a proof of principle, we compute the four-gluon process in the leading-color approximation. We discuss the new method, analyze its numerical properties, and apply it to reconstruct the analytic form of the amplitudes. The numerical method is universal, and can be automated to provide multiscale two-loop computations for phenomenologically relevant signatures at hadron colliders.

6.
Internist (Berl) ; 57(8): 811-4, 2016 Aug.
Article in German | MEDLINE | ID: mdl-27167633

ABSTRACT

A 33-year-old refugee from Nigeria, who had been living in Germany for 1 year, was admitted to the hospital due to pelvic pain, peranal hemorrhage, and an unexplained increase in transaminase levels. As the liver screening tests, sonography findings, and colonoscopy were normal, a liver biopsy was performed that revealed Schistosoma mansoni worm eggs as an unexpected diagnostic finding. Serological tests for specific antibodies and parasitological egg detection in the stool confirmed the diagnosis. After only temporary response to a short-term and low-dose treatment with praziquantel, a 3-day high-dose (40 mg/kg body weight) treatment with praziquantel finally led to long-lasting symptom relief.


Subject(s)
Anus Diseases/diagnosis , Hemorrhage/diagnosis , Liver Diseases/diagnosis , Praziquantel/administration & dosage , Schistosomiasis mansoni/diagnosis , Schistosomiasis mansoni/drug therapy , Adult , Anthelmintics/therapeutic use , Anus Diseases/complications , Anus Diseases/prevention & control , Diagnosis, Differential , Hemorrhage/complications , Hemorrhage/prevention & control , Humans , Liver Diseases/complications , Liver Diseases/prevention & control , Liver Function Tests , Male , Nigeria , Refugees , Schistosomiasis mansoni/complications , Therapeutics , Transaminases/blood
7.
Phys Rev Lett ; 109(4): 042001, 2012 Jul 27.
Article in English | MEDLINE | ID: mdl-23006076

ABSTRACT

We present the cross sections for production of up to four jets at the Large Hadron Collider, at next-to-leading order in the QCD coupling. We use the BLACKHAT library in conjunction with SHERPA and a recently developed algorithm for assembling primitive amplitudes into color-dressed amplitudes. We adopt the cuts used by ATLAS in their study of multijet events in pp collisions at √s=7 TeV. We include estimates of nonperturbative corrections and compare to ATLAS data. We store intermediate results in a framework that allows the inexpensive computation of additional results for different choices of scale or parton distributions.

8.
Cell Death Dis ; 3: e358, 2012 Jul 26.
Article in English | MEDLINE | ID: mdl-22833097

ABSTRACT

We have recently found that D(-)lentiginosine, a synthetic iminosugar exerting glucosidase inhibitory activity, but not its natural enantiomer lentiginosine, is endowed with an unexpected, pro-apoptotic activity. Here, we investigated mechanisms involved in apoptosis induced by D(-)lentiginosine in MOLT-3, HT-29 and SH-SY5Y tumour cell lines. The results showed that D(-)lentiginosine increased caspase 9 expression at 18 h in all the cell lines from 1.5-3.1 folds. Cytochrome c in the cytoplasm was found to be increased from 2.3-2.6 folds in treated cells with respect to control cells. These effects were accompanied by a remarkable collapse of the mitochondrial membrane potential and by the downregulation of anti-apoptotic genes, as well as the upregulation of pro-apoptotic genes of the Bcl-2 family. U937Bcl-2 transfectants, highly expressing Bcl-2, were reluctant to undergo apoptosis even following treatment with 500 µM D(-)lentiginosine, whereas apoptosis by D(-)lentiginosine was induced also in U937 cells, naturally deficient in P53. Thus, our study establishes that the enantiomer of a natural iminosugar is endowed with a possible anti-tumorigenic effect that might be ascribed not only to their capacity to inhibit glycosidases but also to other unknown mechanisms. These data encourage further investigation on similar compounds to make them an interesting platform for the generation of new anticancer drugs.


Subject(s)
Alkaloids/pharmacology , Apoptosis/drug effects , Tumor Suppressor Protein p53/metabolism , BH3 Interacting Domain Death Agonist Protein/metabolism , Caspase 9/metabolism , Cell Line, Tumor , Cytochromes c/metabolism , HT29 Cells , Humans , Membrane Potential, Mitochondrial/drug effects , Proto-Oncogene Proteins c-bcl-2/metabolism , Stereoisomerism , bcl-2-Associated X Protein/metabolism
9.
J Phys Condens Matter ; 23(41): 415901, 2011 Oct 19.
Article in English | MEDLINE | ID: mdl-21946859

ABSTRACT

Anelastic and dielectric spectroscopy measurements on PbZr(1-x)Ti(x)O(3) (PZT) close to the morphotropic (MPB) and antiferroelectric boundaries provide new insight into some controversial aspects of its phase diagram. No evidence is found of a border separating monoclinic (M) from rhombohedral (R) phases, in agreement with recent structural studies supporting a coexistence of the two phases over a broad composition range x<0.5, with the fraction of M increasing toward the MPB. It is also discussed why the observed maximum of elastic compliance appears to be due to a rotational instability of the polarization linearly coupled to shear strain. Therefore it cannot be explained by extrinsic softening from finely twinned R phase alone, but indicates the presence also of M phase, not necessarily homogeneous.A new diffuse transition is found within the ferroelectric phase near x ~ 0.1, at a temperature T(IT) higher than the well established boundary T(T) to the phase with tilted octahedra. It is proposed that around T(IT) the octahedra start rotating in a disordered manner and finally become ordered below T(T). In this interpretation, the onset temperature for octahedral tilting monotonically increases up to the antiferroelectric transition of PbZrO(3), and the depression of T(T)(x) below x=0.18 would be a consequence of the partial relief of the mismatch between the average cation radii with the initial stage of tilting below T(IT).

10.
Phys Rev Lett ; 106(9): 092001, 2011 Mar 04.
Article in English | MEDLINE | ID: mdl-21405617

ABSTRACT

We present the next-to-leading order (NLO) QCD results for W+4-jet production at hadron colliders. This is the first hadron-collider process with five final-state objects to be computed at NLO. It represents an important background to many searches for new physics at the energy frontier. Total cross sections, as well as distributions in the jet transverse momenta, are provided for the initial LHC energy of √s = 7 TeV. We use a leading-color approximation, known to be accurate to 3% for W production with fewer jets. The calculation uses the BLACKHAT library along with the SHERPA package.

11.
Arch Virol ; 156(3): 397-403, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21140178

ABSTRACT

We have characterized the virome in single grapevines by 454 high-throughput sequencing of double-stranded RNA recovered from the vine stem. The analysis revealed a substantial set of sequences similar to those of fungal viruses. Twenty-six putative fungal virus groups were identified from a single plant source. These represented half of all known mycoviral families including the Chrysoviridae, Hypoviridae, Narnaviridae, Partitiviridae, and Totiviridae. Three of the mycoviruses were associated with Botrytis cinerea, a common fungal pathogen of grapes. Most of the rest appeared to be undescribed. The presence of viral sequences identified by BLAST analysis was confirmed by sequencing PCR products generated from the starting material using primers designed from the genomic sequences of putative mycoviruses. To further characterize these sequences as fungal viruses, fungi from the grapevine tissue were cultured and screened with the same PCR probes. Five of the mycoviruses identified in the total grapevine extract were identified again in extracts of the fungal cultures.


Subject(s)
Biodiversity , High-Throughput Nucleotide Sequencing , Plant Viruses/isolation & purification , RNA Viruses/isolation & purification , Sequence Analysis, DNA , Vitis/virology , Cluster Analysis , Fungi/virology , Molecular Sequence Data , Phylogeny , Plant Viruses/classification , Plant Viruses/genetics , RNA Viruses/classification , RNA Viruses/genetics
12.
Rev. Soc. Esp. Dolor ; 17(5): 239-241, jun.-jul. 2010.
Article in Spanish | IBECS | ID: ibc-81297

ABSTRACT

La Esclerosis Múltiple (EM), es una enfermedad del SNC siendo 2 veces más frecuente su aparición en mujeres, el 70% de ellas en edad fértil. Desde el punto de vista anestésico nos encontramos ante una enfermedad con elevada susceptibilidad neurológica que podría agravarse tanto por la propia cirugía, la técnica anestésica como por la medicación utilizada. Por otra parte se plantea como atender la demanda de analgesia para el trabajo de parto en mujeres con EM, que es el grupo de edad con mayor incidencia de la enfermedad. Presentamos el caso de una mujer de 37 años diagnosticada de esclerosis múltiples 3 años antes, forma recidivante, remitente. La paciente es ingresada en dilatación con 37 semanas de amenorrea, presentando una buena evolución del trabajo de parto y encontrándose el feto en situación longitudinal y presentación cefálica. Avisan al Servicio de Anestesia para valoración de la indicación de epidural para analgesia del parto. La gestante previamente había acudido a consulta de preanestesia donde se le había informado del riesgo beneficio de la técnica y en concreto en su caso, habiendo entendido perfectamente las posibles complicaciones derivadas de la misma y firmado el consentimiento informado. Nosotros hemos preferido utilizar una técnica locoregional, vía epidural considerando también el riesgo potencial de cesárea urgente, para evitar, dado el caso la realización de una técnica intraraquídea o una anestesia general, con las posibilidades de desencadenar un brote que tienen estas técnicas. Además de aportar confort a la paciente durante el trabajo de parto, proporcionar analgesia durante el mismo, disminuye por este motivo el estrés de la gestante pudiendo paralelamente evitar la aparición de un brote (AU)


Multiple sclerosis (MS) is a disease of the central nervous system (CNS), and twice as prevalent in women, 70% of whom are of fertile age. From an anaesthetics point of view, due to it being a disease with a high neurological susceptibility it can be aggravated by, the surgery itself, the anaesthetic technique and the medication used. On the other hand, it is about how to meet the demand for analgesia during labour by women with MS, which is the age group with a higher incidence of the disease. We present the case of a 37 year-old woman who was diagnosed 3 years before with a remitting, recurring Multiple Sclerosis. The patient was admitted in dilation in the 37th week of gestation. Labour was progressing well and the foetus was in a longitudinal lie and cephalic presentation. The Anaesthesia Department was informed to assess the indication of an epidural for analgesia during labour. The patient had been seen previously in a pre-anaesthesia clinic were she was informed of the risks and benefits of the technique and in her case in particular. Having understood the possible complications arising from this, she had signed the informed consent. We prefer to use the local/regional epidural technique, bearing in mind the potential risk of an urgent caesarean. This is also to avoid, as is the cases when performing an intra-spinal technique or general anaesthesia, the possibilities of triggering a rash, which can occur with these techniques. Besides giving comfort to the patient during labour, it provides analgesia, and for this reason reduces stress in the patient, as well as being able to prevent a rash appearing (AU)


Subject(s)
Humans , Female , Adult , Analgesia, Epidural/methods , Analgesia, Epidural , Labor, Obstetric , Multiple Sclerosis/complications , Multiple Sclerosis/drug therapy , Neuromuscular Agents/therapeutic use , Central Nervous System/pathology , Gastrointestinal Hemorrhage/complications , Gastrointestinal Hemorrhage/diagnosis , Amenorrhea/complications , Hypotension/complications
13.
Phys Rev Lett ; 102(22): 222001, 2009 Jun 05.
Article in English | MEDLINE | ID: mdl-19658855

ABSTRACT

We report on the first next-to-leading order QCD computation of W+3-jet production in hadronic collisions including all partonic subprocesses. We compare the results with data from the Tevatron and find excellent agreement. The required one-loop matrix elements are computed using on-shell methods, implemented in a numerical program, BlackHat. We use the SHERPA package to generate the real-emission contributions and to integrate the various contributions over phase space. We use a leading-color (large-N_{c}) approximation for the virtual part, which we confirm in W+1, 2-jet production to be valid to within three percent.

15.
Phys Rev Lett ; 98(25): 255701, 2007 Jun 22.
Article in English | MEDLINE | ID: mdl-17678037

ABSTRACT

We present anelastic and dielectric spectroscopy measurements of PbZr(1-x)Ti(x)O(3) with 0.455 < or = x < or = 0.53, which provide new information on the low-temperature phase transitions. The tetragonal-to-monoclinic transformation is first order for x < 0.48 and causes a softening of the polycrystal Young's modulus whose amplitude may exceed the one at the cubic-to-tetragonal transformation; this is explainable in terms of linear coupling between shear strain components and tilting angle of polarization in the monoclinic phase. The transition involving rotations of the octahedra below 200 K is visible both in the dielectric and anelastic losses, and it extends within the tetragonal phase, as predicted by recent first-principle calculations.

16.
Phys Rev Lett ; 93(9): 097601, 2004 Aug 27.
Article in English | MEDLINE | ID: mdl-15447139

ABSTRACT

The dynamic dielectric susceptibility and the elastic compliance of the relaxor ferroelectric lanthanum lead zirconate titanate (PLZT) 9/65/35 have been measured under different cooling and heating protocols in order to study aging and memory. The memory of multiple aging stages at different temperatures has been found (several dips in the susceptibility curves on heating), as in spin glass systems below the glass transition. Remarkably, in PLZT the memory of several aging stages is retained also above the freezing temperature deduced from the dynamic susceptibilities. The results are discussed in light of the existing models of aging and memory in spin and dipolar glasses.

17.
Bioinformatics ; 20(16): 2848-50, 2004 Nov 01.
Article in English | MEDLINE | ID: mdl-15117758

ABSTRACT

UNLABELLED: RRE allows the extraction of non-coding regions surrounding a coding sequence [i.e. gene upstream region, 5'-untranslated region (5'-UTR), introns, 3'-UTR, downstream region] from annotated genomic datasets available at NCBI. AVAILABILITY: RRE parser and web-based interface are accessible at http://www.bioinformatica.unito.it/bioinformatics/rre/rre.html


Subject(s)
Database Management Systems , Databases, Nucleic Acid , Information Storage and Retrieval/methods , Sequence Alignment/methods , Sequence Analysis, DNA/methods , Software , Untranslated Regions/genetics , Chromosome Mapping/methods , Documentation/methods
18.
Org Lett ; 3(9): 1367-9, 2001 May 03.
Article in English | MEDLINE | ID: mdl-11348236

ABSTRACT

[reaction in text] Straightforward total syntheses of (-)-rosmarinecine have been achieved from L-malic acid derived pyrroline N-oxides by two novel useful cascade processes, which join the family of domino reactions. Both strategies, which furnished the target alkaloid in enantioenriched and enantiopure forms, respectively, allow complete control of configuration at all the three newly created contiguous stereogenic centers.


Subject(s)
Alkaloids/chemical synthesis , Pyrrolizidine Alkaloids , Alkaloids/chemistry , Magnetic Resonance Spectroscopy , Malates/chemistry , Molecular Structure , Pyrroles/chemistry , Stereoisomerism , Structure-Activity Relationship
19.
Chem Commun (Camb) ; (17): 1590-1, 2001 Sep 07.
Article in English | MEDLINE | ID: mdl-12240396

ABSTRACT

The synthesis of a new Gly-Pro turn mimetic and the computational study of its ability to induce beta-turn is reported.


Subject(s)
Dipeptides/chemistry , Dipeptides/chemical synthesis , Glycine/chemistry , Molecular Mimicry , Proline/chemistry , Computer Simulation , Models, Molecular , Molecular Structure , Protein Structure, Secondary
20.
Org Lett ; 2(16): 2475-7, 2000 Aug 10.
Article in English | MEDLINE | ID: mdl-10956525

ABSTRACT

The enantiomerically pure indolizidine (-)-21 has been synthesized starting from L-malic acid. The key intermediate 20 has been assembled through an intramolecular 1,3-dipolar cycloaddition of a nitrone generated in situ by retrocycloaddition from isoxazolidine 17 or 18. The configuration of the new three stereocenters was set up with complete control in the cycloaddition step. The presented synthetic route provides a general and highly selective methodology toward indolizidines having the [1,8a]-cis configuration.


Subject(s)
Indolizines/chemistry , Indolizines/chemical synthesis , Hydroxylation , Indicators and Reagents , Models, Molecular , Molecular Conformation , Nitrogen Oxides , Stereoisomerism , Structure-Activity Relationship
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