41 research outputs found
Mouse mammary tumor virus-like gene sequences are present in lung patient specimens
<p>Abstract</p> <p>Background</p> <p>Previous studies have reported on the presence of Murine Mammary Tumor Virus (MMTV)-like gene sequences in human cancer tissue specimens. Here, we search for MMTV-like gene sequences in lung diseases including carcinomas specimens from a Mexican population. This study was based on our previous study reporting that the INER51 lung cancer cell line, from a pleural effusion of a Mexican patient, contains MMTV-like <it>env </it>gene sequences.</p> <p>Results</p> <p>The MMTV-like <it>env </it>gene sequences have been detected in three out of 18 specimens studied, by PCR using a specific set of MMTV-like primers. The three identified MMTV-like gene sequences, which were assigned as INER6, HZ101, and HZ14, were 99%, 98%, and 97% homologous, respectively, as compared to GenBank sequence accession number <ext-link ext-link-id="AY161347" ext-link-type="gen">AY161347</ext-link>. The INER6 and HZ-101 samples were isolated from lung cancer specimens, and the HZ-14 was isolated from an acute inflammatory lung infiltrate sample. Two of the <it>env </it>sequences exhibited disruption of the reading frame due to mutations.</p> <p>Conclusion</p> <p>In summary, we identified the presence of MMTV-like gene sequences in 2 out of 11 (18%) of the lung carcinomas and 1 out of 7 (14%) of acute inflamatory lung infiltrate specimens studied of a Mexican Population.</p
Breeding systems in Tolpis (Asteraceae) in the Macaronesian islands: the Azores, Madeira and the Canaries
Plants on oceanic islands often originate from
self-compatible (SC) colonizers capable of seed set by self fertilization. This fact is supported by empirical studies,
and is rooted in the hypothesis that one (or few) individuals
could find a sexual population, whereas two or more would
be required if the colonizers were self-incompatible (SI).
However, a SC colonizer would have lower heterozygosity
than SI colonizers, which could limit radiation and diver sification of lineages following establishment. Limited
evidence suggests that several species-rich island lineages
in the family Asteraceae originated from SI colonizers with
some ‘‘leakiness’’ (pseudo-self-compatibility, PSC) such
that some self-seed could be produced. This study of Tolpis
(Asteraceae) in Macaronesia provides first reports of the
breeding system in species from the Azores and Madeira,
and additional insights into variation in Canary Islands.
Tolpis from the Azores and Madeira are predominately SI
but with PSC. This study suggests that the breeding sys tems of the ancestors were either PSC, possibly from a
single colonizer, or from SI colonizers by multiple dis seminules either from a single or multiple dispersals. Long distance colonists capable of PSC combine the advantages
of reproductive assurance (via selfing) in the establishment
of sexual populations from even a single colonizer with the
higher heterozygosity resulting from its origin from an
outcrossed source population. Evolution of Tolpis on the
Canaries and Madeira has generated diversity in breeding
systems, including the origin of SC. Macaronesian Tolpis is
an excellent system for studying breeding system evolution
in a small, diverse lineage.info:eu-repo/semantics/publishedVersio
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
On the synchronization of 1D and 2D multi-scroll chaotic oscillators
In this chapter, the guidelines to synchronize one-directional (1D) and two-directional (2D) multi-scroll chaos generators by means of Generalized Hamiltonian forms are presented. First, the multi-scroll chaotic oscillator is simulated at the electronic system level by applying state-variables and piecewise-linear approaches. Besides, we apply scaling procedures to modify the breaking points, slopes and frequency of the chaotic signals in order to reduce their excursion levels within practical values for electronic devices. Second, a chaotic synchronization scheme for multi-directional multi-scroll chaos generators is introduced. We use Generalized Hamiltonian forms approach to determine the synchronization conditions when one and two state-variables of the master system are sent to control the nonlinear functions in the slave system. Additionally, two schemes are set-up to transmit encrypted binary and analog signals by applying chaotic switching technique and additive chaotic masking, respectively. Both schemes are implemented by using traditional operational amplifiers. Finally, theoretical results are confirmed by performing numerical and SPICE simulation results. © Springer-Verlag Berlin Heidelberg 2013.Peer Reviewe
N-scroll chaotic attractors from saturated function series employing CCII+s
The generation of n-scroll chaotic attractors by using saturated nonlinear function series (SNFS) realized with positive-type second generation current conveyors (CCII+s), is introduced. The nonlinear dynamical system is expressed by a third-order differential equation and to carry out numerical simulations, SNFS are ideally modeled by using staircase functions. Therefore, numerical simulations are introduced to approximate the swings, widths, breakpoints and equilibrium points of the n-scroll attractors by considering, as input variables: the dynamic range associated to active devices, gain of the nonlinear system and the number of scrolls. Therefore, its dynamical behavior is investigated in the state space. Besides, the CCII± is a versatile analog building block and it has been demonstrated to be very useful in several linear and nonlinear applications, since CCII-based implementations offer better performances that Opamps-based implementations in terms of accuracy and bandwidth. Therefore, the nonlinear system is synthesized with CCII+s to generate 3- and 4-scrolls. HSPICE simulations and experimental results are shown to verify the agreement on the behavior of the proposed circuit and the numerical simulations.This work has been supported by Promep
Mexico, under the project numbers UATLX-PTC-088, UATLX-CA-197, by CONACyT-Mexico, under the project number 48396-Y and by Consejeria de Innovacion, Ciencia y
Empresa, Junta de Andalucia, Spain, under the project number TIC-2532. The first author thanks the support of the JAE-Doc
program of CSIC, co-funded by FSE.Peer reviewe
Frequency limitations from the circuit realization of saw-tooth based multi-scroll oscillators
Since multi-scroll chaotic oscillators are known to have many challenges due to the parasitic effects in the circuit implementation, this paper analyzes their effect on the non-ideal slopes and presence of delays in the realization of the saw-tooth nonlinear function which is used to generate these oscillators. The proposed analysis and description is applicable for any comparator-based nonlinear functions, but followed by a particular dynamical multi-scroll system, which is observed to generate positive Lyapunov exponents for some regions of operation. This process helps us to get insights regarding the potential spectra limit related to a saw-tooth nonlinear function circuit.Peer Reviewe
Chaos-based communication systems by applying Hamiltonian synchronization
In this paper, two chaos-based communication schemes to transmit encrypted information are presented. We use Generalized Hamiltonian forms approach to synchronize two unidirectionally coupled n-scrolls chaotic attractors. First, a scheme is set-up to transmit binary signals by applying chaotic switching technique. Both coupling signal and confidential message are send by only one transmission channel. Additionally, a second scheme is also proposed to encrypted analog signals by using chaotic additive masking, which uses two transmission channels. Finally, theoretical results are confirmed by SPICE simulations to show the usefulness of the proposed communication schemes.Peer Reviewe
On the trade-off between the number of scrolls and the operating frequency of the chaotic attractors
A trade-off analysis on the number of scrolls and the operating frequency is presented. To do so, nonlinear system parameters, real physical active device parameters and the operating frequency are taken into account to model the behavior of the saturated nonlinear function series approximated by a piecewise-linear description. As a consequence, not only the trade-off between the number of scrolls and the operating frequency is investigated, which depends directly on the behavior at the operating frequency of the nonlinear function, but also chaotic attractors are efficiently synthesized without the application of scaling techniques. Theoretical calculations are in good agreement with numerical simulations and a prediction on the maximum number of scrolls that can be synthesized for a particular frequency is also given.Peer Reviewe