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1.
Catheter Cardiovasc Interv ; 103(1): 160-168, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38059295

RESUMO

BACKGROUND: New vascular closure devices (VCD) are being introduced for achieving hemostasis after transcatheter aortic valve implantation (TAVI). However, no safety or efficacy data have been published compared to other contemporary VCD. AIM: To compare the safety and efficacy of suture-based Perclose Prostyle as compared to plug-based MANTA device. METHODS: A total of 408 consecutive TAVI patients from two high volume TAVI centers were included in the present study. Patients were grouped according to VCD: Prostyle versus MANTA. Propensity score matching (PSM) and multivariable analysis were utilized to compare clinical endpoints between the two groups. The primary endpoint was any vascular complication (VC) according to VARC-3 criteria. RESULTS: After PSM, a total of 264 patients were analyzed, of them 132 in each group. Overall baseline characteristics of the two groups were comparable. Primary end-point was similar between MANTA as compared to Prostyle (16.7% vs. 15.3% respectively, p = 0.888). The main driver for VC among MANTA group were minor vascular complications (15.2%). Conversely, minor and major VC contributed equally to the primary endpoint among Prostyle group (7.6%) (p = 0.013). No outcome predictors were identified in multivariate analysis. CONCLUSIONS: VCD for transfemoral TAVI using the new-generation Prostyle device or the MANTA device achieved comparable VARC-3 VC rates.


Assuntos
Estenose da Valva Aórtica , Cateterismo Periférico , Substituição da Valva Aórtica Transcateter , Dispositivos de Oclusão Vascular , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Cateterismo Periférico/efeitos adversos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Técnicas Hemostáticas/efeitos adversos
2.
Phys Rev Lett ; 130(21): 211001, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37295105

RESUMO

We present the observation of a charge-sign dependent solar modulation of galactic cosmic rays (GCRs) with the Calorimetric Electron Telescope onboard the International Space Station over 6 yr, corresponding to the positive polarity of the solar magnetic field. The observed variation of proton count rate is consistent with the neutron monitor count rate, validating our methods for determining the proton count rate. It is observed by the Calorimetric Electron Telescope that both GCR electron and proton count rates at the same average rigidity vary in anticorrelation with the tilt angle of the heliospheric current sheet, while the amplitude of the variation is significantly larger in the electron count rate than in the proton count rate. We show that this observed charge-sign dependence is reproduced by a numerical "drift model" of the GCR transport in the heliosphere. This is a clear signature of the drift effect on the long-term solar modulation observed with a single detector.


Assuntos
Radiação Cósmica , Voo Espacial , Telescópios , Prótons , Elétrons
3.
Phys Rev Lett ; 130(17): 171002, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172251

RESUMO

We present the results of a direct measurement of the cosmic-ray helium spectrum with the CALET instrument in operation on the International Space Station since 2015. The observation period covered by this analysis spans from October 13, 2015, to April 30, 2022 (2392 days). The very wide dynamic range of CALET allowed for the collection of helium data over a large energy interval, from ∼40 GeV to ∼250 TeV, for the first time with a single instrument in low Earth orbit. The measured spectrum shows evidence of a deviation of the flux from a single power law by more than 8σ with a progressive spectral hardening from a few hundred GeV to a few tens of TeV. This result is consistent with the data reported by space instruments including PAMELA, AMS-02, and DAMPE and balloon instruments including CREAM. At higher energy we report the onset of a softening of the helium spectrum around 30 TeV (total kinetic energy). Though affected by large uncertainties in the highest energy bins, the observation of a flux reduction turns out to be consistent with the most recent results of DAMPE. A double broken power law is found to fit simultaneously both spectral features: the hardening (at lower energy) and the softening (at higher energy). A measurement of the proton to helium flux ratio in the energy range from 60 GeV/n to about 60 TeV/n is also presented, using the CALET proton flux recently updated with higher statistics.

5.
Phys Rev Lett ; 131(19): 191001, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38000434

RESUMO

Detailed measurements of the spectral structure of cosmic-ray electrons and positrons from 10.6 GeV to 7.5 TeV are presented from over 7 years of observations with the CALorimetric Electron Telescope (CALET) on the International Space Station. The instrument, consisting of a charge detector, an imaging calorimeter, and a total absorption calorimeter with a total depth of 30 radiation lengths at normal incidence and a fine shower imaging capability, is optimized to measure the all-electron spectrum well into the TeV region. Because of the excellent energy resolution (a few percent above 10 GeV) and the outstanding e/p separation (10^{5}), CALET provides optimal performance for a detailed search of structures in the energy spectrum. The analysis uses data up to the end of 2022, and the statistics of observed electron candidates has increased more than 3 times since the last publication in 2018. By adopting an updated boosted decision tree analysis, a sufficient proton rejection power up to 7.5 TeV is achieved, with a residual proton contamination less than 10%. The observed energy spectrum becomes gradually harder in the lower energy region from around 30 GeV, consistently with AMS-02, but from 300 to 600 GeV it is considerably softer than the spectra measured by DAMPE and Fermi-LAT. At high energies, the spectrum presents a sharp break around 1 TeV, with a spectral index change from -3.15 to -3.91, and a broken power law fitting the data in the energy range from 30 GeV to 4.8 TeV better than a single power law with 6.9 sigma significance, which is compatible with the DAMPE results. The break is consistent with the expected effects of radiation loss during the propagation from distant sources (except the highest energy bin). We have fitted the spectrum with a model consistent with the positron flux measured by AMS-02 below 1 TeV and interpreted the electron+positron spectrum with possible contributions from pulsars and nearby sources. Above 4.8 TeV, a possible contribution from known nearby supernova remnants, including Vela, is addressed by an event-by-event analysis providing a higher proton-rejection power than a purely statistical analysis.

6.
J Hum Evol ; 185: 103441, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37857126

RESUMO

Hispanopithecus laietanus from the Late Miocene (9.8 Ma) of Can Llobateres 1 (CLL1; Vallès-Penedès Basin, NE Iberian Peninsula) represents one of the latest occurrences of fossil apes in Western mainland Europe, where they are last recorded at ∼9.5 Ma. The paleoenvironment of CLL1 is thus relevant for understanding the extinction of European hominoids. To refine paleoenvironmental inferences for CLL1, we apply ecometric models based on functional crown type (FCT) variables-a scoring scheme devised to capture macroscopic functional traits of occlusal shape and wear surfaces of herbivorous large mammal molars. Paleotemperature and paleoprecipitation estimates for CLL1 are provided based on published regional regression models linking average FCT of large herbivorous mammal communities to climatic conditions. A mapping to Whittaker's present-day biome classification is also attempted based on these estimates, as well as a case-based reasoning via canonical variate analysis of FCT variables from five relevant biomes. Estimates of mean annual temperature (25 °C) and mean annual precipitation (881 mm) classify CLL1 as a tropical seasonal forest/savanna, only in partial agreement with the canonical variate analysis results, which classify CLL1 as a tropical rainforest with a higher probability. The former biome agrees better with previous inferences derived from fossil plants and mammals, as well as preliminary isotopic data. The misclassification of CLL1 as a tropical forest is attributed to the mixture of forest-adapted taxa with others adapted to more open environments, given that faunal and plant composition indicates the presence of a dense wetland/riparian forest with more open woodlands nearby. The tested FCT ecometric approaches do not provide unambiguous biome classification for CLL1. Nevertheless, our results are consistent with those from other approaches, thus suggesting that FCT variables are potentially useful to investigate paleoenvironmental changes through time and space-including those that led to the extinction of European Miocene apes.


Assuntos
Hominidae , Dente , Animais , Fósseis , Europa (Continente) , Ecossistema , Plantas , Mamíferos
7.
Curr Microbiol ; 80(4): 133, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36897421

RESUMO

Health care-associated infections (HAIs) contribute to a significant rate of morbidity, mortality, and financial burden on health systems. These infections are caused by multidrug-resistant bacteria that produce biofilm as the main virulence factor. This study aimed to evaluate the effect of the copper-based metallic compounds [Cu(phen)(pz)NO2]Cl (I), [Cu(bpy)(pz)(NO2)]Cl (II), and [Cu(phen)(INA)NO2]Cl (III), where phen = phenanthroline, bpy = bipyridine, pz = pyrazinamide, and INA = isonicotinic acid, against planktonic cells and biofilms formation of Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli. The susceptibility of the microorganisms was evaluated by minimum inhibitory concentration (MIC), minimum bacterial concentration (MBC), and time-kill curve assay on planktonic cells. The biofilm formation was evaluated by biomass quantification through staining with crystal violet (CV), colony-forming units (CFUs) quantification, and biofilm metabolic activity determination by XTT assay. The compounds showed bacteriostatic and bactericidal activity on all microorganisms analyzed. Regarding the antibiofilm activity, all metallic compounds were able to reduce significantly the biofilm biomass, colony-forming units, and the metabolic activity of remaining cells, varying the efficient concentration according to the strain analyzed. Interestingly, compounds (I), (II) and (III) did not exhibit DNA degradation activity even with up to 100 µM of these metal complexes. On the other hand, complexes (I) and (III) showed a remarkable capacity to cleave DNA upon addition of glutathione, a reducing agent (CuII/CuI) that leads to reactive oxygen species (ROS) formation. The results presented in this study showed promising antimicrobial and antibiofilm effects.


Assuntos
Anti-Infecciosos , Infecção Hospitalar , Humanos , Antibacterianos/farmacologia , Cobre/farmacologia , Dióxido de Nitrogênio/farmacologia , Anti-Infecciosos/farmacologia , Bactérias , Biofilmes , Atenção à Saúde , Testes de Sensibilidade Microbiana
8.
Phys Rev Lett ; 128(13): 131103, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426700

RESUMO

The relative abundance of cosmic ray nickel nuclei with respect to iron is by far larger than for all other transiron elements; therefore it provides a favorable opportunity for a low background measurement of its spectrum. Since nickel, as well as iron, is one of the most stable nuclei, the nickel energy spectrum and its relative abundance with respect to iron provide important information to estimate the abundances at the cosmic ray source and to model the Galactic propagation of heavy nuclei. However, only a few direct measurements of cosmic-ray nickel at energy larger than ∼3 GeV/n are available at present in the literature, and they are affected by strong limitations in both energy reach and statistics. In this Letter, we present a measurement of the differential energy spectrum of nickel in the energy range from 8.8 to 240 GeV/n, carried out with unprecedented precision by the Calorimetric Electron Telescope (CALET) in operation on the International Space Station since 2015. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The particle's energy is measured by a homogeneous calorimeter (1.2 proton interaction lengths, 27 radiation lengths) preceded by a thin imaging section (3 radiation lengths) providing tracking and energy sampling. This Letter follows our previous measurement of the iron spectrum [1O. Adriani et al. (CALET Collaboration), Phys. Rev. Lett. 126, 241101 (2021).PRLTAO0031-900710.1103/PhysRevLett.126.241101], and it extends our investigation on the energy dependence of the spectral index of heavy elements. It reports the analysis of nickel data collected from November 2015 to May 2021 and a detailed assessment of the systematic uncertainties. In the region from 20 to 240 GeV/n our present data are compatible within the errors with a single power law with spectral index -2.51±0.07.

9.
Phys Rev Lett ; 129(10): 101102, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36112450

RESUMO

A precise measurement of the cosmic-ray proton spectrum with the Calorimetric Electron Telescope (CALET) is presented in the energy interval from 50 GeV to 60 TeV, and the observation of a softening of the spectrum above 10 TeV is reported. The analysis is based on the data collected during ∼6.2 years of smooth operations aboard the International Space Station and covers a broader energy range with respect to the previous proton flux measurement by CALET, with an increase of the available statistics by a factor of ∼2.2. Above a few hundred GeV we confirm our previous observation of a progressive spectral hardening with a higher significance (more than 20 sigma). In the multi-TeV region we observe a second spectral feature with a softening around 10 TeV and a spectral index change from -2.6 to -2.9 consistently, within the errors, with the shape of the spectrum reported by DAMPE. We apply a simultaneous fit of the proton differential spectrum which well reproduces the gradual change of the spectral index encompassing the lower energy power-law regime and the two spectral features observed at higher energies.

10.
Phys Rev Lett ; 129(25): 251103, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36608255

RESUMO

We present the measurement of the energy dependence of the boron flux in cosmic rays and its ratio to the carbon flux in an energy interval from 8.4 GeV/n to 3.8 TeV/n based on the data collected by the Calorimetric Electron Telescope (CALET) during ∼6.4 yr of operation on the International Space Station. An update of the energy spectrum of carbon is also presented with an increase in statistics over our previous measurement. The observed boron flux shows a spectral hardening at the same transition energy E_{0}∼200 GeV/n of the C spectrum, though B and C fluxes have different energy dependences. The spectral index of the B spectrum is found to be γ=-3.047±0.024 in the interval 25

11.
J Hum Evol ; 170: 103237, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35988385

RESUMO

The Abocador de Can Mata (ACM) composite stratigraphic sequence (els Hostalets de Pierola, Vallès-Penedès Basin, NE Iberian Peninsula) has yielded a diverse primate assemblage from the late Aragonian (Middle to Late Miocene). Detailed litho-, bio-, and magnetostratigraphic control has enabled an accurate dating of these fossil remains. Comparable data, however, were lacking for the nearby locality of Can Mata 1 (CM1), which yielded a dryopithecine canine of a female individual. Given the lack of hipparionin equids and giraffids, CM1 has been correlated to the latest Aragonian (Mammal Neogene [MN] zone MN7+8). Here we revise the age of CM1 based on fieldwork and associated paleomagnetic samplings undertaken in 2018-2021. Our results extend the ACM composite sequence upward and indicate that CM1 correlates to the earliest Vallesian (MN9). The updated ACM sequence has a thickness of ∼300 m and comprises 12 magnetozones correlated to subchrons C5Ar.1r to C5n.2n (∼12.6-11.1 Ma; latest MN6 to earliest MN9, late Aragonian to earliest Vallesian). CM1 is correlated to C5r.1r (11.146-11.056 Ma), with an interpolated age of 11.11 Ma, thus postdating the dispersal of hipparionin horses into the Vallès-Penedès Basin-which is correlated to the previous subchron C5r.1n, with an interpolated age of 11.18 Ma, and by definition marks the beginning of the Vallesian. CM1 also minimally postdates the earliest record of giraffids at ACM-representing their earliest well-dated occurrence in the basin-being correlated to C5r.1n with an interpolated age of 11.11 Ma. We conclude that CM1 has an earliest Vallesian (MN9) age of ∼11.1 Ma, intermediate between the Aragonian dryopithecins and the Vallesian hispanopithecins. Ongoing paleontological surveillance at ACM thus offers the prospect to yield additional earliest Vallesian ape remains, which are essential to clarify their taxonomic allocation as well as to confirm whether hispanopithecins evolved locally from dryopithecins rather than immigrating from elsewhere during MN9.


Assuntos
Hominidae , Animais , Cães , Feminino , Fósseis , Cavalos , Mamíferos , Paleontologia , Primatas , Répteis
12.
Catheter Cardiovasc Interv ; 100(5): 832-838, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36116033

RESUMO

OBJECTIVE: Patients with rapidly deteriorating clinical status due to severe aortic stenosis are often referred for expedited transcatheter aortic valve replacement (TAVR). Data regarding the outcome of such interventions is limited. We aimed to evaluate the outcome of patients undergoing expedited TAVR. DESIGN AND SETTING: Data were derived from the Israeli Multicenter Registry. SUBJECTS: Subjects were divided into two groups based on procedure urgency: patients who were electively hospitalized for the procedure (N = 3140) and those who had an expedited TAVR (N = 142). Procedural and periprocedural complication rates were significantly higher among patients with an expedited indication for TAVR compared to those having an elective procedure: valve malposition 4.6% versus 0.6% (p < 0.001), procedural cardiopulmonary resuscitation 4.3% versus 1.0% (p = 0.007), postprocedure myocardial infarction 2.0% versus 0.4% (p = 0.002), and stage 3 acute kidney injury 3.0% versus 1.1%, (p < 0.001). Patients with expedited indication for TAVR had significantly higher in hospital mortality (5.6% vs. 1.4%, p = 0.003). Kaplan-Meier's survival analysis showed that patients undergoing expedited TAVR had higher 3-year mortality rates compared to patients undergoing an elective TAVR procedure (p < 0.001). Multivariate analysis found that patients with expedited indication had fourfolds increased risk of in-hospital mortality (odds ratio: 4.07, p = 0.001), and nearly twofolds increased risk of mortality at 3-year (hazard ratio: 1.69, p = 0.001) compared to those having an elective procedure. CONCLUSION: Patients with expedited indications for TAVR suffer from poor short- and long-term outcomes. It is important to characterize and identify these patients before the deterioration to perform TAVR in a fast-track pathway to minimize their procedural risk.


Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Resultado do Tratamento , Índice de Gravidade de Doença , Fatores de Risco , Catéteres
13.
BMC Biol ; 19(1): 6, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33461551

RESUMO

BACKGROUND: The two main primate groups recorded throughout the European Miocene, hominoids and pliopithecoids, seldom co-occur. Due to both their rarity and insufficiently understood palaeoecology, it is currently unclear whether the infrequent co-occurrence of these groups is due to sampling bias or reflects different ecological preferences. Here we rely on the densely sampled primate-bearing sequence of Abocador de Can Mata (ACM) in Spain to test whether turnovers in primate assemblages are correlated with palaeoenvironmental changes. We reconstruct dietary evolution through time (ca. 12.6-11.4 Ma), and hence climate and habitat, using tooth-wear patterns and carbon and oxygen isotope compositions of enamel of the ubiquitous musk-deer Micromeryx. RESULTS: Our results reveal that primate species composition is strongly correlated with distinct environmental phases. Large-bodied hominoids (dryopithecines) are recorded in humid, densely-forested environments on the lowermost portion of the ACM sequence. In contrast, pliopithecoids inhabited less humid, patchy ecosystems, being replaced by dryopithecines and the small-bodied Pliobates toward the top of the series in gallery forests embedded in mosaic environments. CONCLUSIONS: These results support the view that pliopithecoid primates preferred less humid habitats than hominoids, and reveal that differences in behavioural ecology were the main factor underpinning their rare co-occurrence during the European Miocene. Our findings further support that ACM hominoids, like Miocene apes as a whole, inhabited more seasonal environments than extant apes. Finally, this study highlights the importance of high-resolution, local investigations to complement larger-scale analyses and illustrates that continuous and densely sampled fossiliferous sequences are essential for deciphering the complex interplay between biotic and abiotic factors that shaped past diversity.


Assuntos
Evolução Biológica , Catarrinos/fisiologia , Dieta/veterinária , Características de História de Vida , Animais , Ecossistema , Fósseis , Espanha
14.
J Med Libr Assoc ; 110(1): 126-132, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35210973

RESUMO

Twenty fifteen marked the year of assessment for the Millennium Development Goals (MDGs). The MDGs that achieved the greatest success were those where evidence-based practice (EBP) interventions were implemented. The ability to practice evidence-based medicine is grounded in the creation of and access to medical literature that synthesizes research findings. The role that global health literature played in the success of the MDGs demonstrates that medical libraries and librarians have a role to play in achieving the Sustainable Development Goals (SDGs). Librarians can hold capacity-building workshops that provide instruction on how to access evidence-based literature and also train health professionals to conduct synthesis research. Research findings conducted by in-country health professionals are more likely to address issues being faced by local communities and will afford the possibility of obtaining the necessary evidence-based answers that can then be used to implement policies to resolve public health issues identified in the SDGs. This paper discusses how an international team of librarians leveraged funding from a Medical Library Association/Librarians without Borders/Elsevier Foundation/Research4Life grant to hold a capacity-building workshop in Zimbabwe and follow-up online trainings. The workshop focused on accessing evidence-based resources and conducting synthesis research. Outcomes included the creation and policy implementation of evidence-based knowledge products in alignment with local needs and galvanizing a multisectoral group of key individuals who have gone on to collaborate toward the vision of creating a Zimbabwe innovation hub. Looking ahead, such grants can be leveraged to conduct capacity-building to support knowledge translation and other local training needs.


Assuntos
Bibliotecários , Desenvolvimento Sustentável , Fortalecimento Institucional , Países em Desenvolvimento , Saúde Global , Humanos
15.
J Acad Ethics ; 20(3): 421-436, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34131418

RESUMO

University human research ethics application procedures can be complicated and daunting, especially for international students unfamiliar with the process and the language. We conducted focus groups and interviews with four research higher degree and 21 Master's coursework international students at an Australian university to gain their views on the human ethics application process. We found the most important influences on their experience were: the time it took to do an application; support from supervisors, peers and others; their own language skills; and their lack of familiarity with research ethics procedures. To improve the experience of international students undertaking research involving human research ethics applications, we recommend universities provide guidance on institutional ethics review processes, concepts and terminology, with translations in a range of languages, together with guidance on how to conduct research ethically within and outside the students' own countries. We also recommend curricula be developed to further students' understanding of the importance of ethical research practice, and that these curricula be embedded in undergraduate and postgraduate degree programs and reflected in course learning outcomes.

16.
Phys Rev Lett ; 126(24): 241101, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213922

RESUMO

The Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray iron over a wide energy interval. In this Letter a measurement of the iron spectrum is presented in the range of kinetic energy per nucleon from 10 GeV/n to 2.0 TeV/n allowing the inclusion of iron in the list of elements studied with unprecedented precision by space-borne instruments. The measurement is based on observations carried out from January 2016 to May 2020. The CALET instrument can identify individual nuclear species via a measurement of their electric charge with a dynamic range extending far beyond iron (up to atomic number Z=40). The energy is measured by a homogeneous calorimeter with a total equivalent thickness of 1.2 proton interaction lengths preceded by a thin (3 radiation lengths) imaging section providing tracking and energy sampling. The analysis of the data and the detailed assessment of systematic uncertainties are described and results are compared with the findings of previous experiments. The observed differential spectrum is consistent within the errors with previous experiments. In the region from 50 GeV/n to 2 TeV/n our present data are compatible with a single power law with spectral index -2.60±0.03.

17.
Phys Rev Lett ; 126(7): 071103, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666466

RESUMO

ANITA's fourth long-duration balloon flight in 2016 detected 29 cosmic-ray (CR)-like events on a background of 0.37_{-0.17}^{+0.27} anthropogenic events. CRs are mainly seen in reflection off the Antarctic ice sheets, creating a phase-inverted waveform polarity. However, four of the below-horizon CR-like events show anomalous noninverted polarity, a p=5.3×10^{-4} chance if due to background. All anomalous events are from locations near the horizon; ANITA-IV observed no steeply upcoming anomalous events similar to the two such events seen in prior flights.

18.
Catheter Cardiovasc Interv ; 98(7): E990-E999, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34347381

RESUMO

OBJECTIVES: This study aimed to compare permanent pacemaker implantation (PPMI) rates among patients undergoing Trans-catheter Aortic Valve Implantation (TAVI) with first generation (G1) versus second generation (G2) valves and the impact of PPMI on long-term mortality. BACKGROUND: PPMI is a known adverse event after TAVI. Recently, two novel iterations of valve designs of both the balloon expandable valves (BEV) and self-expanding valves (SEV) were introduced as a second generation valves. METHODS: All patients included in the Israeli multicenter TAVI registry were grouped according to valve type (BEV vs. SEV) and generation (G1 vs. G2). A comparison was made for clinical and outcome indices of patients undergoing TAVI with G1 and G2 in each of the valve systems. RESULTS: A total of 1377 patients were included. The incidence of PPMI did not differ between G1-BEV versus G2-BEV (15.3% vs. 17.4%; p = 0.598) nor between G1-SEV versus G2-SEV (23.4% vs. 20.3%; p = 0.302). Depth of implantation and complete right bundle branch block were independently associated with PPMI post-TAVI in both valve systems. PPMI was not associated with an increased risk for 2-year mortality. CONCLUSIONS: The incidence of PPMI remains a relevant adverse event post-TAVI even when the newer generation valves are used. Since the predictors for PPMI are well established, a standardized approach for the management of conduction disorders is much needed.


Assuntos
Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Marca-Passo Artificial , Substituição da Valva Aórtica Transcateter , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Humanos , Estudos Retrospectivos , Fatores de Risco , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
19.
J Biol Chem ; 294(25): 9995-10005, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31097544

RESUMO

Caldicellulosiruptor bescii is an extremely thermophilic, cellulolytic bacterium with a growth optimum at 78 °C and is the most thermophilic cellulose degrader known. It is an attractive target for biotechnological applications, but metabolic engineering will require an in-depth understanding of its primary pathways. A previous analysis of its genome uncovered evidence that C. bescii may have a completely uncharacterized aspect to its redox metabolism, involving a tungsten-containing oxidoreductase of unknown function. Herein, we purified and characterized this new member of the aldehyde ferredoxin oxidoreductase family of tungstoenzymes. We show that it is a heterodimeric glyceraldehyde-3-phosphate (GAP) ferredoxin oxidoreductase (GOR) present not only in all known Caldicellulosiruptor species, but also in 44 mostly anaerobic bacterial genera. GOR is phylogenetically distinct from the monomeric GAP-oxidizing enzyme found previously in several Archaea. We found that its large subunit (GOR-L) contains a single tungstopterin site and one iron-sulfur [4Fe-4S] cluster, that the small subunit (GOR-S) contains four [4Fe-4S] clusters, and that GOR uses ferredoxin as an electron acceptor. Deletion of either subunit resulted in a distinct growth phenotype on both C5 and C6 sugars, with an increased lag phase, but higher cell densities. Using metabolomics and kinetic analyses, we show that GOR functions in parallel with the conventional GAP dehydrogenase, providing an alternative ferredoxin-dependent glycolytic pathway. These two pathways likely facilitate the recycling of reduced redox carriers (NADH and ferredoxin) in response to environmental H2 concentrations. This metabolic flexibility has important implications for the future engineering of this and related species.


Assuntos
Biomassa , Firmicutes/metabolismo , Gliceraldeído 3-Fosfato Desidrogenase (NADP+)/metabolismo , Gliceraldeído 3-Fosfato/química , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Glicólise , Caldicellulosiruptor , Firmicutes/crescimento & desenvolvimento , Gliceraldeído 3-Fosfato/metabolismo , Metaboloma , Oxirredução , Filogenia
20.
Phys Rev Lett ; 125(25): 251102, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33416351

RESUMO

In this paper, we present the measurement of the energy spectra of carbon and oxygen in cosmic rays based on observations with the Calorimetric Electron Telescope on the International Space Station from October 2015 to October 2019. Analysis, including the detailed assessment of systematic uncertainties, and results are reported. The energy spectra are measured in kinetic energy per nucleon from 10 GeV/n to 2.2 TeV/n with an all-calorimetric instrument with a total thickness corresponding to 1.3 nuclear interaction length. The observed carbon and oxygen fluxes show a spectral index change of ∼0.15 around 200 GeV/n established with a significance >3σ. They have the same energy dependence with a constant C/O flux ratio 0.911±0.006 above 25 GeV/n. The spectral hardening is consistent with that measured by AMS-02, but the absolute normalization of the flux is about 27% lower, though in agreement with observations from previous experiments including the PAMELA spectrometer and the calorimetric balloon-borne experiment CREAM.

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