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Colloidal quantum dots (cQDs), semiconductor materials with widely tunable properties, can be printed in submicrometer patterns through electrohydrodynamic printing, avoiding aggressive photolithography steps. Postprinting ligand exchange determines the final optoelectronic properties of the cQD structures. However, achieving a complete bulk exchange is challenging, and the conventional vibrational analysis lacks the required spatial resolution. Infrared nanospectroscopy enables quantitative analysis of vibrational signals and structural topography on the nanometer scale upon ligand substitution on lead sulfide cQDs. A solution of ethanedithiol led to rapid (∼60 s) exchange of ≤90% of the ligands, in structures up to ∼750 nm thick. Prolonged exposures (>1 h) caused the degradation of the microstructures, with a systematic removal of cQDs regulated by surface:bulk ratios and solvent interactions. This study establishes a method for the development of devices through a combination of tunable photoactive materials, additive manufacturing of microstructures, and their quantitative nanometer-scale analysis.

The upgrade to JT-60SA tokamak (R = 3 m, a = 1.2 m) was conducted within a Europe-Japan collaboration agreement featuring the implementation of superconducting magnets. In 2021, the magnet system commissioning was initiated, undergoing cool-down and energization of the 18 Nb-Ti Toroidal Field (TF) coils (400 tonnes) up to full nominal current. TF energization was smoothly processed but it was observed during current load a higher outlet temperature increase of TF02 coil versus others, indicating a higher resistance in this coil circuit and therefore a possible risk in future operation. The present paper analyses the different risk factors that can impact the TF operation safety margins and their quantitative contribution. To this end on the one hand ad-hoc thermal & thermo-hydraulic models were developed by CEA and F4E to represent the TF02 whole circuit including feeder zone where high resistance is suspected to be located. The outcomes of those models on chosen TF and PF current scenarios including transient loads and their impact on temperature margin in risky zones such as terminal joint (TJ) are presented. On the another hand a 3D electrical circuit of TJ was modelled using TF cables tomography, giving a realistic quantitative insight into local current distribution, therefore on current sharing temperature. The analyses outcomes synthesis is depicted under strategic considerations and tentatively contributes to establishing guidelines for future operation scenarios in which magnets will undergo demanding conditions.

The MAgnet Design Explorer (MADE) is a Tokamak design algorithm developed initially for the DTT CS, and largely extended within the EUROfusion DEMO project [1]. MADE could function as a valuable tool for navigating the initial design stage of a tokamak project. In response to the technological developments in recent years, it has been deemed necessary to define a means capable of estimating how machine size and performance change in response to the target parameters imposed by plasma physics and by the performance of the superconducting magnet system. The MADE algorithm previously included two sequenced macro-blocks, the first dedicated to defining the toroidal magnetic field system, and the second to define the central solenoid of the machine. These macro-blocks generate two of the three main magnetic systems of the Tokamak. This paper describes the studies completed to define and implement the third macro-block, which models the poloidal coil system and the plasma vertical stability. The resulting suite of algorithms are now combined to reach an optimized winding pack architecture for all major tokamak coils at a given plant operating point. A case study based on ITER is presented in this work.

In the ITER project, the Poloidal Field (PF) and Correction Coils (CC) - all made of Nb-Ti conductors - share the same supercritical Helium cooling loop at about 4.5 K. Recently, the associated thermo-hydraulic model developed with SuperMagnet has been updated to obtain a more accurate description of this cryomagnetic system. These changes include integration of feeders, more detailed cryodistribution circuits and refined coil geometries, with the general aim at approaching as much as possible the as-built configuration. In parallel, currents, magnetic field maps and magnet heat loads (mainly AC losses) associated with the ITER DINA 2016 plasma scenario have been included in this model together with refined nuclear heating to evaluate the corresponding PF and CC conductor minimum temperature margins; the objective being to ensure that they remain above the specification value of 1.5 K.

The ITER magnet system comprises 18 superconducting Toroidal Field Coils (TFC) based on Nb3Sn conductor supplied with the operational nominal current of 68 kA to produce a toroidal magnetic field of 5.2 T at the plasma major radius R = 6.2 m. A Magnet Cold Test Bench (MCTB) to test the TFC at 4 K up to a current value of 68 kA is under construction at ITER Organization (IO) site. The foreseen test conditions are substantially different from those corresponding to the 18-coil operation as the coils will be tested individually in horizontal position and supported at a few locations along the case. On the one hand, the magnetic field distribution produced by one single coil yields a different pattern of Lorentz forces. On the other hand, the absence of case wedging results in a reduced structural stiffness of the analyzed system. Finite element analysis work on this subject has been reported in the past for the TF Winding Pack (WP) after impregnation without undergoing the enclosure in the case, showing that the TF WP could be tested in safe conditions at a reduced energization of 15 kA (20% of the nominal current). This work considers currents up to the nominal 68 kA and the TF case which provides additional stiffness to the coil. Prior to the energization load, the coil is subject to gravity and cooled down to 4 K.

This paper provides an overview on the engineering analyses workflow typically executed in support of the assembly and operation of superconducting magnet systems, in particular for ITER. Accurate field computations are required to evaluate (1) Lorentz forces as primary loads on magnets (2) cable temperature margins (3) critical error field harmonics and (4) field lines tracing. Although the required accuracy increases with each of these magnetic computations, their common aim, beyond use during machine design, is to provide estimates on the final alignment of magnetic fields and, possibly, to guide and adjust magnet installation. Two global mechanical models (18 TF and 2 TF coils) featuring their interfaces to the Pre-Compression Rings, CS and PF coils are used to assess the impact of tolerances and misalignments on the final coils’ positions in operation so to guide, with the aid of metrology data, the assembly process. With these, we also evaluate the mechanical stresses during current tests at 4 K if performed before final installation. A global and several local models of the Pre-Compression Rings that must be mounted in the tokamak were developed and used to design the tightening sequence during PCRs assembly and the required assembly tooling. Magnet systems also require sophisticated models to predict conductor temperature margins and to assist during thermal transients (magnets cooldown). Thermal loads due to Joule losses in cold structures are evaluated with 3D eddy-current codes and nuclear heating with detailed Monte-Carlo models suited to simulate streaming and deep penetration 3D phenomena leading to nuclear power deposition in the cables.

In this chapter I analyse the function of pulque in the film Roma (Alfonso Cuarón, 2018) and its relationship with Cleo, the protagonist of the film. We will see how this drink is one of the most relevant in the sacred Mexican cosmogony and to what extent Cuarón uses this mythical background to give symbolic density to the remembrance of her childhood. A childhood marked by the feminine in the absence of the paternal level. [ABSTRACT FROM AUTHOR]

Memory and rejuvenation effects in the magnetic response of off-equilibrium spin glasses have been widely regarded as the doorway into the experimental exploration of ultrametricity and temperature chaos. Unfortunately, despite more than twenty years of theoretical efforts following the experimental discovery of memory and rejuvenation, these effects have, thus far, been impossible to reliably simulate. Yet, three recent developments convinced us to accept this challenge: first, the custom-built Janus II supercomputer makes it possible to carry out simulations in which the very same quantities that can be measured in single crystals of CuMn are computed from the simulation, allowing for a parallel analysis of the simulation and experimental data. Second, Janus II simulations have taught us how numerical and experimental length scales should be compared. Third, we have recently understood how temperature chaos materializes in aging dynamics. All these three aspects have proved crucial for reliably reproducing rejuvenation and memory effects on the computer. Our analysis shows that at least three different length scales play a key role in aging dynamics, whereas essentially all the theoretical analyses of the aging dynamics emphasize the presence and crucial role of a single glassy correlation length.

The AID/APOBEC polynucleotide cytidine deaminases have historically been classified as either DNA mutators or RNA editors based on their first identified nucleic acid substrate preference. DNA mutators can generate functional diversity at antibody genes but also cause genomic instability in cancer. RNA editors can generate informational diversity in the transcriptome of innate immune cells, and of cancer cells. Members of both classes can act as antiviral restriction factors. Recent structural work has illuminated differences and similarities between AID/APOBEC enzymes that can catalyse DNA mutation, RNA editing or both, suggesting that the strict functional classification of members of this family should be reconsidered. As many of these enzymes have been employed for targeted genome (or transcriptome) editing, a more holistic understanding will help improve the design of therapeutically relevant programmable base editors.

Conocer la opinión de los profesionales de enfermería de una Unidad de Cuidados Intensivos Polivalente (UCI) respecto a los efectos de la visita abierta en el paciente, en la familia y en la actividad diaria de los profesionales, así como sus aportaciones a la actual política de visitas abiertas.

This paper describes the development and testing of a lab plant that emulates a water supply pumping system with the objective of testing optimal pumping strategies based on standard solvers. The emulated system consists of two tanks that supply the water to two districts in a town. There are two pumps, that can fill the tanks through a reconfigurable hydraulic system with several valves. The automatic controller determines the valves and pumps that are active at each instant of time in order to minimize the operation cost, taking into account the electric tariff periods. Some aspects on the development of the lab plant are first discussed, including hydraulic aspects and real time control implementation issues. Then, a mathematical model is proposed to be able to formulate, in matrix form, the cost index and the constraints, such that, standard solvers as Mosek or CBC can be used. The full optimization proposal is tested on several experiments, and compared to some simulations, to demonstrate the validity of the plant and the optimization approach.

The relative σ-donating and π-accepting capacities of a range of synthetically relevant boryl anions have been evaluated by examining the geometric, thermochemical, and electronic properties of their adducts to the Li+cation and Se atom, as compared to the properties of the analogous neutral N-heterocyclic carbenes (NHCs), by theoretical methods. The results indicate that boryl anions have a weaker π-accepting capability compared to NHCs, but it is still a non-negligible factor in the bonding contributions between boryl and the Se atom. The tunability of the π-accepting capacity of boryl anions is similar to that of NHCs, indicating a potential for the modification of the electronic properties of metal complexes incorporating either boryl or NHC ligands. In all cases, the boryl ligands were found to be superior σ-donors to NHCs.

Automatic music transcription can be defined as the analysis of the acoustic signal to extract a symbolic representation of music. Existing transcription systems typically consider just the notes played at a given moment; however, other aspects such as expressiveness and playing technique can also be considered. This work is focused on how chords are played. Specifically, we consider a special type of chords, those played in arpeggio style, or simply arpeggios, in which the notes are played fast, sequentially from the lowest to the highest pitched note or vice versa and with a large overlap of the notes' sound. The main goal of this paper is to determine the pitch direction in which the arpeggiated chord was played. Two different classification methods are considered: a Fisher linear discriminant and an SVM linear classification scheme. Different features are presented for this task: one is based on the Mel-frequency cepstral coefficients (MFCCs) and two others, specifically designed for this task, rely on different analyses of the spectrogram. Evaluations have been done with a wide number of musical instruments. The results show that the pitch direction can be reliably detected using the proposed methods.

In the last years, extensive attention has been paid on designing and developing functional imaging contrast agents for providing accurate noninvasive evaluation of pathology in vivo. However, the issue of false-positives or ambiguous imaging and the lack of a robust strategy for simultaneous dual-mode imaging remain to be fully addressed. One effective strategy for improving it is to rationally design magnetic resonance imaging (MRI) contrast agents (CAs) with intrinsic T1/T2dual-mode imaging features. In this work, the development and characterization of one-pot synthesized nanostructured coordination polymers (NCPs) which exhibit dual mode T1/T2MRI contrast behavior is described. The resulting material comprises the combination of different paramagnetic ions (Fe3+, Gd3+, Mn2+) with selected organic ligands able to induce the polymerization process and nanostructure stabilization. Among them, the Fe-based NCPs showed the best features in terms of colloidal stability, low toxicity, and dual T1/T2MRI contrast performance overcoming the main drawbacks of reported CAs. The dual-mode CA capability was evaluated by different means: in vitro phantoms, ex vivo and in vivo MRI, using a preclinical model of murine glioblastoma. Interestingly, the in vivo MRI of Fe–NCPs show T1and T2high contrast potential, allowing simultaneous recording of positive and negative contrast images in a very short period of time while being safer for the mouse. Moreover, the biodistribution assays reveals the persistence of the nanoparticles in the tumor and subsequent gradual clearance denoting their biodegradability. After a comparative study with commercial CAs, the results suggest these nanoplatforms as promising candidates for the development of dual-mode MRI CAs with clear advantages.

Hematopoietic stem cell transplantation is usually performed without considering the ABO compatibility between donor and recipient. There are few studies analyzing ABO matching impact on transfusion outcome of umbilical cord blood transplantation (UCBT) recipients. The aim of this study was to analyze factors influencing transfusion outcome, highlighting the ABO matching between donor and recipient. This study has reviewed data from 318 patients who underwent single unit UCBT at la Fe University Hospital from January 2000 to December 2014. There were no differences between RBC and platelet (PLT) requirements or RBC and PLT transfusion independence according to ABO matching between donor and recipient. RBC and PLT requirements were statistically correlated (ρ=0,841, P<0.001). A total of 170 and 188 patients achieved RBC and PLT independence, respectively, within 180 days after UCBT. Persistence of recipient isoagglutinins was detected in 6.8% of patients with major ABO incompatibility at median of 176 days (103–269) after UCBT. Autoimmune haemolytic anemia was diagnosed in 15 patients, 12 of them due to cold antibodies. In conclusion, ABO matching has not influenced transfusion requirements of patients undergoing UCBT.

Throughout the filmography of the Japanese filmmaker Kore-eda Hirokazu a series of themes related to death, memory or assumption of the loss are repeated, often in relation to the father figure. From Dare mo (Nobody Knows, 2004) through Aruitemo aruitemo (Still Walking, 2008), Kiseki (I wish, 2011), Soshite chichi ni naru (Like Father like Son, 2013), Umimachi Diary (Our Little Sister, 2015), to the last released film Umi yorimo mada fukaku (After the Storm, 2016), we find an absent father that causes a number of everyday dramatic disasters in the lives of his relatives. Kore-eda is usually compared to the classic filmmaker Ozu Yasujiro for his sober mise-enscene, a mythomania often fed by the same Kore-eda; but beyond this influence, where has the symbolic father of his master's films gone? In this analysis I am going to interpret some representative scenes of symbolic violence that this absence provokes in the child. [ABSTRACT FROM AUTHOR]

The JAK-STAT pathway has a substantial role in lymphoid precursor cell proliferation, survival and differentiation. Nonetheless, the contribution of JAK2 to T-cell lymphoblastic lymphoma (T-LBL) development remains poorly understood. We have identified one activating TEL-JAK2 translocation and four missense mutations accumulated in 2 out of 16 T-LBL samples. Two of them are novel JAK2 mutations and the other two are reported for the first time in T-LBL. Notably, R683G and I682T might have arisen owing to RNA editing. Mutated samples showed different mutated transcripts suggesting sub-clonal heterogeneity. Functional approaches revealed that two JAK2 mutations (H574R and R683G) constitutively activate JAK-STAT signaling in γ2A cells and can drive the proliferation of BaF3-EpoR cytokine-dependent cell line. In addition, aberrant hypermethylation of SOCS3 might contribute to enhance the activation of JAK-STAT signaling. Of utmost interest is that primary T-LBL samples harboring JAK2 mutations exhibited increased expression of LMO2, suggesting a mechanistic link between JAK2 mutations and the expression of LMO2, which was confirmed for the four missense mutations in transfected γ2A cells. We therefore propose that active JAK2 contribute to T-LBL development by two different mechanisms, and that the use of pan-JAK inhibitors in combination with epigenetic drugs should be considered in future treatments.

We report measurements of the dynamics of the charge-density-wave systems K0.3MoO3and NbSe3applying the quite recent technique of meV-resolution inelastic X-ray scattering (IXS). In K0.3MoO3, serving as a test-case with existing reference results from neutron scattering, the very steep slope of the phason dispersion has been reproduced by IXS together with a very good agreement for the observed “phason velocity": 26$km/sec$(IXS) $vs.$23$km/sec$(neutrons). In NbSe3, where IXS allows for dispersion studies on thin whiskers, the longitudinal acoustic and one transverse acoustic (TA1) branch propagating along the NbSe3-chain direction have been determined at room temperature. Low temperature TA1-data have been taken around the upper-CDW satellite position (0, 0.241, 0) at temperatures down to below the upper Peierls transition (Tp=145K). The low temperature results indicate the absence of a Kohn anomaly, in contrast to the CDW-related dynamics observed in K0.3MoO3and KCP, but similar as in (TaSe4)2I.

In this paper, we present a method for monophonic singing transcription based on hysteresis defined on the pitch-time curve. This method is designed to perform note segmentation even when the pitch evolution during the same note behaves unstably, as in the case of untrained singers. The selected approach estimates the regions in which the chroma is stable, these regions are classified as voiced or unvoiced according to a decision tree classifier using two descriptors based on aperiodicity and power. Then, a note segmentation stage based on pitch intervals of the sung signal is carried out. To this end, a dynamic averaging of the pitch curve is performed after the beginning of a note is detected in order to roughly estimate the pitch. Deviations of the actual pitch curve with respect to this average are measured to determine the next note change according to a hysteresis process defined on the pitch-time curve. Finally, each note is labeled using three single values: rounded pitch (to semitones), duration and volume. Also, a complete evaluation methodology that includes the definition of different relevant types of errors, measures and a method for the computation of the evaluation measures are presented. The proposed system improves significantly the performance of the baseline approach, and attains results similar to previous approaches.

We have determined the spatial distribution of the local charge-density-wave (CDW) strain in the sliding state of NbSe3. The strain is measured by monitoring the spatially-varying shift q(x) of the CDW satellite wave vector between current contacts. Experiments were carried out at T = 90 K in the upper CDW state using high spatial resolution (30-50 µm) X-ray diffraction. Applying direct currents about twice the threshold value, we observe a steep exponential decrease of the shift within a few hundred microns from the contact followed by a linear variation of q in the central section of the sample. This latter regime is attributed to transverse pinning of the CDW dislocation loops (DL), while the exponential regime is controlled by the finite DL nucleation rate. Additional to these data in the stationary state of the sliding CDW, we investigated the relaxation of the CDW strain q(t) upon switching off the current (T = 75 K). Using time-resolved high-spatial resolution X-ray diffraction, we observe at 800 µm from the electrode a decay law of the stretched exponential type : q(t) = qoexp(-(t/τ)µ) , with τ = 283 ms and µ = 0.37.

We confirm recent results obtained in a previous work by studying the Ising spin glass at finite magnetic field in four dimensions. Different approaches to this problem suggest the existence of a critical line similax to that found in mean-field theory but in a universality class different of the transition at zero magnetic field. Problems due to the strong nature of the finite-size corrections within a magnetic field are also discussed.

In this paper, a method for automatic reduction of dissonance in recorded isolated chords is proposed. Previous approaches address this problem using source separation and note-level processing. In our approach, we manipulate the harmonic structure as a whole in order to avoid beating partials which, according to prior research on dissonance perception, typically produce an unpleasant sound. The proposed system firstly performs a sinusoidal plus residual modeling of the input and analyses the various fundamental frequencies present in the chord. This information is used to create a symbolic representation of the in-tune version of the input according to some musical rules. Then, the partials of the signals are shifted in order to fit the in-tune harmonic structure of the input chord. The input is assumed to contain one isolated chord, with relatively stable fundamental frequencies belonging to the Western chromatic scale. The evaluation has been performed by 31 expert musicians, which have quantified the perceived consonance of six varied, out-of-tune chords in three variants: unprocessed, processed with our system and processed by a state-of-the-art commercial tool (Melodyne Editor). The proposed approach attains an important reduction of the perceived dissonance, showing better performance than Melodyne Editor for most of the cases evaluated.

Abstract: We describe Janus, a massively parallel FPGA-based computer optimized for the simulation of spin glasses, theoretical models for the behavior of glassy materials. FPGAs (as compared to GPUs or many-core processors) provide a complementary approach to massively parallel computing. In particular, our model problem is formulated in terms of binary variables, and floating-point operations can be (almost) completely avoided. The FPGA architecture allows us to run many independent threads with almost no latencies in memory access, thus updating up to 1024 spins per cycle. We describe Janus in detail and we summarize the physics results obtained in four years of operation of this machine; we discuss two types of physics applications: long simulations on very large systems (which try to mimic and provide understanding about the experimental non-equilibrium dynamics), and low-temperature equilibrium simulations using an artificial parallel tempering dynamics. The time scale of our non-equilibrium simulations spans eleven orders of magnitude (from picoseconds to a tenth of a second). On the other hand, our equilibrium simulations are unprecedented both because of the low temperatures reached and for the large systems that we have brought to equilibrium. A finite-time scaling ansatz emerges from the detailed comparison of the two sets of simulations. Janus has made it possible to perform spin-glass simulations that would take several decades on more conventional architectures. The paper ends with an assessment of the potential of possible future versions of the Janus architecture, based on state-of-the-art technology.

Abstract: We review the main features of charge order observation by means of Resonant (Elastic) X-ray Scattering. Different cases have been studied during the past 12 years (NaV2O5, NdNiO3, Fe3O4, BaVS3, manganites, ...) that have allowed us to develop a systematic approach for data collection, correction and data analysis.

Using high-resolution x-ray scattering, in the temperature range 40 K $

The dynamic performance of a ballasted track and three types of slab track is analysed and compared by means of a comprehensive dynamic model of the train–track system, generated using two commercial analysis software packages: the commercial multibody system (MBS) analysis software SIMPACK and the finite element method (FEM) analysis software NASTRAN. The use of a commercial MBS software makes it possible to include, in a reliable way, models of advanced non-linear wheel–rail contact as well as complex elements or joints in the vehicle model, while the FEM the flexibility of the rail and the slab to be taken into account. As a result, a combined MBS–FEM representation of the vehicle–track model is integrated into the MBS software, which allows for the study of dynamic phenomena in a wide frequency range. In this study, other simpler approaches for modelling the dynamic vehicle–track interaction are also considered, such as pure multibody or FE representations of the whole vehicle–track system. The quality of the results obtained with the different types of models used is analysed, and some conclusions are put forth regarding the possible validity of rather simple train–track interaction model types under certain conditions as well as the most suitable configuration of the most complex models.

Although barley is extensively grown in the Peruvian highlands as a food crop, agronomic and quality performance are poor. In addition, there are few reports of the successful application of modern technologies, such as doubled haploidy, in developing nations. Double-haploid technique was used to obtain barley cultivars better suited to this environment. From barley crosses Ya/LM94, B16/LM94 and B12/LM94, four promising double-haploid lines were evaluated in the highland Acobamba Farming Community along with their parents and two control cultivars (PPch, UNA80). Double-haploid lines, Ya/LM94-PC27 and B12/LM94-PC34, were the most agronomically acceptable. Here we describe their potential economic benefits for Acobamba farmers. Both reached the best quality grade based on hectoliter mass, and should therefore obtain the highest market price, and provide the best incomes, gains, and profitability rates. In comparison, PPch and UNA80 if grown would be unprofitable, and LM94 would be markedly less profitable. Use of the double-haploid technique in our breeding program was estimated to cut research expenses by 26%, due to the shorter time for cultivar improvement.

Tobacco mosaic virus(TMV) has served as a model organism for pathbreaking work in plant pathology, virology, biochemistry and applied genetics for more than a century. We were intrigued by a photograph published in Phytopathologyin 1934 showing that Tabasco pepper plants responded to TMV infection with localized necrotic lesions, followed by abscission of the inoculated leaves. This dramatic outcome of a biological response to infection observed by Francis O. Holmes, a virologist at the Rockefeller Institute for Medical Research, was used to score plants for resistance to TMV infection. Our objective was to gain a better understanding of early to mid-twentieth century ideas of genetic resistance to viruses in crop plants. We investigated Holmes’ observation as a practical exercise in reworking an experiment, having been inspired by Pamela Smith’s innovative Making and Knowing Project. We had a great deal of difficulty replicating Holmes’ experiment, finding that biological materials and experimental customs change over time, in ways that ideas do not. Using complementary tools plus careful study and interpretation of the original text and figures, we were able to rework, yet only partially replicate, this experiment. Reading peer-reviewed manuscripts that cited Holmes’ 1934 report provided an additional level of insight into the interpretation and replication of this work in the decades that followed. From this, we touch on how experimental reworking can inform our strategies to address the reproducibility “crisis” in twenty-first century science.

Summary: Although pineapple plants have been found to produce proteases ex vitro, most of the biotechnological investigations of this crop have been focused on propagation. The procedure involving the use of temporary immersion bioreactors is one of the most outstanding because of its high multiplication rate. We previously recorded specific protease activity in the culture medium during the pre-elongation step of this protocol. Therefore, we decided to modify the culture medium composition of this phase looking for an increase in protease excretion. Four independent experiments were performed to evaluate the effects of different levels of sucrose (0–350.4 mM), inorganic salts [0–200% Murashige and Skoog (MS) salt strength], inositol (0–2.20 mM), and thiamine (0–1.2μM). The following indicators were recorded: shoot fresh mass per bioreactor; and protein concentration, proteolytic activity, and specific protease activity in culture media. Specific protease activity, the most important indicator recorded, was highest with 262.8 mM sucrose, 100% MS salt strength, 0.3 μM thiamine and no inositol. Results shown here demonstrate that conditions adequate for propagation purposes (87.6 mM sucrose, 100% MS salt strength, 0.55 mM inositol, 0.3 μM thiamine) are not always adequate for protease excretion.

Summary: Biotechnology has become an important tool to produce plant secondary metabolites and proteases are among them. Although pineapple plants have been found to produce proteases, most of the biotechnological investigations on this crop have been focused on propagation. The procedure involving the use of temporary immersion bioreactors is one of the most outstanding because of its high multiplication rate. We previously recorded specific protease activity in the culture medium during the pre-elongation step of this protocol. Therefore we decided to modify this phase, looking for an increase of protease excretion. Three independent experiments were performed to evaluate the effects of culture duration, and levels of gibberellic acid (GA) and 6-benzyladenine (BA). The following indicators were recorded: shoot fresh mass per bioreactor; and protein concentration, proteolytic activity, and specific protease activity in culture media. As happens in investigations focused on protease production, the specific protease activity was the most important indicator recorded here. It maximized at 21 d of culture. Moreover, GA (4.2 μM) increased specific activity in the culture medium while BA produced a negative effect. Results shown here demonstrate that conditions adquate for propagation purposes (15-d pre-elongation phase; 2.8 μM GA; 2.2 μM BA) are not necessarily adequate for protease excretion.

Summary: An in vitro bioassay to differentiate pineapple plant resistance levels to Phytophthora nicotianae var. parasitica (heart rot disease) is deseribed here. Conditions to cause death of in vitro-cultured plants were defined using a cultivar previously found to be susceptible to this fungus in our Field-Grown Pineapple Germplasm Bank (ev. Smooth Cayenne Serrana). The effects of zoospore concentration, inoculation technique, and disease progress during the course of time after infection were evaluated. The highest rates of plant death were observed with the use of 108 zoospores ml−1, and the inoculation technique of needle-mediated leaf base wound. One hundred percent plant death was observed at 144h after infection. Different susceptible varieties along with a resistant pineapple relative were additionally compared. In vitro results confirmed previous observations obtained under field conditions. The protocol described here may be used for early selection (in vitro) of new pineapple genotypes showing resistance to this fungus. At present, this protocol is extensively used in the Biotechnology-assisted Cuban Program for Pineapple Breeding.

We give a topological criterion for the minimality of the strong unstable (or stable) foliation of robustly transitive partially hyperbolic diffeomorphisms. As a consequence we prove that, for $3$-manifolds, there is an open and dense subset of robustly transitive diffeomorphisms (far from homoclinic tangencies) such that either the strong stable or the strong unstable foliation is robustly minimal. We also give a topological condition (existence of a central periodic compact leaf) guaranteeing (for an open and dense subset) the simultaneous minimality of the two strong foliations. AMS 2000 Mathematics subject classification: Primary 37D25; 37C70; 37C20; 37C29

We consider the collapse of a saddle of a horseshoe and a sink via a critical saddle-node bifurcation. In this way one obtains a saddle-node horseshoe. We prove that there is an open set of arcs of diffeomorphisms \{f_\mu\}_{\mu \in I} unfolding generically, say at \mu_0, a saddle-node horseshoe with Hausdorff dimension arbitrarily close to 1/2 so that there is an interval (\mu_0, \mu_0+\varepsilon) in the parameter line such that every diffeomorphism f_\mu, \mu\in (\mu_0, \mu_0+\delta), has a tangency.

Abstract. A procedure for producing pineapple [Ananas comosus (L.) Merr.] transgenic plants was developed that involved selection by micropropagation in temporary immersion bioreactors (TIBs). Pineapple calluses ranging in size from 1.5 mm to 2.0 mm that were co-cultivated with Agrobacterium tumefaciens strains AT2260 (pIG121Hm) and LBA4404 (pTOK233) for 24 h produced the highest percentage (40%) of GUS⁺ calluses. Phosphinothricin and hygromycin, but not kanamycin, were effective selection markers in TIBs. Large-scale transformation experiments with AT2260 (pHCA58) and AT2260 (pHCG59) resulted in up to a 6.6% efficiency of transgenic plant recovery. TIB technology was found to be more efficient for transgenic plant selection than conventional micropropagation. Polymerase chain reaction and genomic Southern blot analyses confirmed the non-chimeric nature of the transgenic plants recovered from TIBs.

Summary: The temporary immersion bioreactor has been found to be an important tool for sugarcane micropropagation, allowing higher shoot formation rates and cost reduction. This research was conducted to demonstrate the agricultural value of temporary immersion bioreactor-derived sugarcane plants. The experiment was carried out for about 2 yr to study the field performance of these plants. Two control treatments were also evaluated representing the conventional forms of micro- and macropropagation. Growth of sugarcane stools, first ratoon and the use of micropropagated plants for macropropagation were recorded. Some botanical and chemical characteristics were evaluated. Differences among propagation systems were only found in the first 6 mo. of field growth, regarding the stem length and diameter. Such differences disappeared with the course of the experiment.

The purpose of this study was to determine whether aspirin (A) ingestion combined with prolonged exercise increases gastrointestinal permeability and whether consumption of a carbohydrate-containing (CHO) or a CHO + glutamine-containing (CHO+G) beverage would reduce this effect. Seventeen subjects completed six experiments. They ingested A (1,300 mg) or placebo (P) pills the evening before and before running 60 min at 70% maximal oxygen uptake. Also, before running they ingested a solution containing 5 g lactulose (L), 5 g sucrose (S), and 2 g rhamnose (R). During each trial, either a 6% CHO beverage, a 6% CHO+G (0.6%; 41 mM) beverage, or a water placebo (WP) was consumed. For 4 h after a run, all urine was collected to measure urinary excretion of L, R, and S. S excretion (percentage of dose ingested; measure of gastroduodenal permeability) was significantly greater (P< 0.05) during the A trial while the subjects drank the WP compared with all other trials. Administration of A also significantly increased L/R (measure of intestinal permeability) for the CHO and WP trials compared with all P trials. Ingestion the CHO or CHO+G beverages significantly reduced S excretion and L excretion when A was administered, but it did not reduce L/R. These results indicate that gastroduodenal and intestinal permeability increase after A ingestion during prolonged running and that ingestion of a CHO beverage attenuates the gastroduodenal effect but not the intestinal effect. Furthermore, addition of G to the CHO beverage provided no additional benefit in reducing gastroduodenal or intestinal permeability.

We study \mathcal{C}^k-diffeomorphisms, k\ge 1, f: M\to M, exhibiting heterodimensional cycles (i.e. cycles containing periodic points of different stable indices). We prove that if f can not be \mathcal{C}^k-approximated by diffeomorphisms with homoclinic tangencies, then f is in the closure of an open set \mathcal{U}\subset \operatorname{Diff}^k(M) consisting of diffeomorphisms g with a non-hyperbolic transitive set \Lambda_g which is locally maximal and strongly partially hyperbolic (the partially hyperbolic splitting at \Lambda_g has three non-trivial directions). As a consequence, in the case of 3-manifolds, we give new examples of open sets of \mathcal{C}^1-diffeomorphisms for which residually infinitely many sinks or sources coexist (\mathcal{C}^1-Newhouse's phenomenon). We also prove that the occurrence of non-hyperbolic dynamics has persistent character in the unfolding of heterodimensional cycles.