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1.
Mol Phylogenet Evol ; 196: 108067, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38561082

RESUMO

In the species groups related to Diphasiastrum multispicatum and D. veitchii, hybridization was investigated in samples from northern and southern Vietnam and the island of Taiwan, including available herbarium specimens from southeast Asia. The accessions were analyzed using flow cytometry (living material only), Sanger sequencing and multiplexed inter-simple sequence repeat genotyping by sequencing. We detected two cases of ancient hybridization involving different combinations of parental species; both led via subsequent duplication to tetraploid taxa. A cross D. multispicatum × D. veitchii from Malaysia represents D. wightianum, a tetraploid taxon according to reported DNA content measurements of dried material (genome formulas MM, VV and MMVV, respectively). The second case involves D. veitchii and an unknown diploid parent (genome formula XX). Three hybridogenous taxa (genome formulas VVX, VVXX, VVVX) were discernable by a combination of flow cytometry and molecular data. Taxon I (VVX, three clones found on Taiwan island) is apparently triploid. Taxon II represents another genetically diverse and sexual tetraploid species (VVXX) and can be assigned to D. yueshanense, described from Taiwan island but occurring as well in mainland China and Vietnam. Taxon III is as well most likely tetraploid (VVVX) and represented by at least one, more likely two, clones from Taiwan island. Taxa I and III are presumably asexual and new to science. Two independently inherited nuclear markers recombine only within, not between these hybrids, pointing towards reproductive isolation. We present an evolutionary scheme which explains the origin of the hybrids and the evolution of new and fully sexual species by hybridization and subsequent allopolyploidization in flat-branched clubmosses.


Assuntos
Hibridização Genética , Lycopodiaceae , Filogenia , Taiwan , Vietnã , Lycopodiaceae/genética , Lycopodiaceae/classificação , DNA de Plantas/genética , Repetições de Microssatélites , Análise de Sequência de DNA , Ilhas , Evolução Molecular , Genoma de Planta , Citometria de Fluxo
2.
Pediatr Surg Int ; 40(1): 60, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421443

RESUMO

BACKGROUND: To lower the risk of testicular malignancies and subfertility, international guidelines recommend orchidopexy for undescended testis (UDT) before the age of 12-18 months. Previous studies reported low rates of 5-15% of timely surgery. Most of these studies are based on DRG and OPS code-based data from healthcare system institutions that do not distinguish between congenital and acquired UDT. METHODS: In a retrospective study data of all boys who underwent orchidopexy in a university hospital and two outpatient surgical departments from 2009 to 2022 were analyzed. The data differentiates congenital from acquired UDT. RESULTS: Out of 2694 patients, 1843 (68.4%) had congenital and 851 (31.6%) had acquired UDT. In 24.9% of congenital cases surgery was performed before the age of 12 months. The median age at surgery for congenital UDT was 16 months (range 7-202). Over the years there was an increased rate of boys operated on before the age of 2 (40% in 2009, 60% in 2022). The median age fluctuated over the years between 21 and 11 months without a trend to younger ages.. The covid pandemic did not lead to an increase of the median age at surgery. The median time between referral and surgery was 46 days (range 1-1836). Reasons for surgery after 12 months of age were a delayed referral to pediatric surgeries (51.2%), followed by relevant comorbidities (28.2%). CONCLUSION: Compared to recent literature, out data show that a closer look at details enables a more realistic approach. Still, there is no trend towards the recommended age for surgical treatment observable, but the rate of timely operated boys with congenital UDT is significantly higher than stated in literature.


Assuntos
Criptorquidismo , Neoplasias Testiculares , Masculino , Criança , Humanos , Orquidopexia , Criptorquidismo/epidemiologia , Criptorquidismo/cirurgia , Estudos Retrospectivos , Hospitais Universitários
3.
Rev Sci Instrum ; 94(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38065134

RESUMO

We present the design and absolute calibration of a charged particle online readout CMOS system tailored for high-power laser experiments. This system equips a Thomson parabola spectrometer, which is used at the Apollon petawatt scale laser facility to measure the spectra of protons produced by high-intensity laser-target interactions. The RadEye1 CMOS matrices array detectors are paired with a custom triggering system for image grabbing. This allows us to register the proton and ion signals remotely. The repetition rate is presently 1 shot/min, but the frame grabbing enables the system to be compatible with modern high-power lasers running, e.g., at 1 Hz. We detail here the implementation, in the harsh electromagnetic environment of such interactions, of the system, and its absolute calibration, which was performed for proton energies from 4 to 20 MeV.

4.
Phys Rev Lett ; 131(11): 116201, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774305

RESUMO

The recent detection of the singular diamagnetism of Dirac electrons in a single graphene layer paved a new way of probing 2D quantum materials through the measurement of equilibrium orbital currents which cannot be accessed in usual transport experiments. Among the theoretical predictions is an intriguing orbital paramagnetism at saddle points of the dispersion relation. Here we present magnetization measurements in graphene monolayers aligned on hexagonal boron nitride crystals. Besides the sharp diamagnetic McClure response at the Dirac point, we detect extra diamagnetic singularities at the satellite Dirac points of the moiré lattice. Surrounding these diamagnetic satellite peaks, we also observe paramagnetic peaks located at the chemical potential of the saddle points of the graphene moiré band structure and relate them to the presence of van Hove logarithmic singularities in the density of states. These findings reveal the long ago predicted anomalous paramagnetic orbital response in 2D systems when the Fermi energy is tuned to the vicinity of saddle points.

5.
Phys Rev Lett ; 130(26): 265101, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37450828

RESUMO

The propagation and energy coupling of intense laser beams in plasmas are critical issues in inertial confinement fusion. Applying magnetic fields to such a setup has been shown to enhance fuel confinement and heating. Here we report on experimental measurements demonstrating improved transmission and increased smoothing of a high-power laser beam propagating in a magnetized underdense plasma. We also measure enhanced backscattering, which our kinetic simulations show is due to magnetic confinement of hot electrons, thus leading to reduced target preheating.


Assuntos
Elétrons , Calefação , Frequência Cardíaca , Cinética , Lasers
6.
Chirurgie (Heidelb) ; 94(7): 651-663, 2023 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-37338573

RESUMO

Fatal accidents due to blunt force trauma are the leading cause of death in children and adolescents [1]. Abdominal trauma is the third most common cause of death after traumatic brain injury and thoracic injuries [2]. Abdominal injury is seen in approximately 2-5% of children involved in accidents [3]. Blunt abdominal injuries are common sequelae of traffic accidents (for example as seat belt injury), falls, and sports accidents. Penetrating abdominal injuries are rare in central Europe. Spleen, liver, and kidney lacerations are the most common injuries after blunt abdominal trauma [4]. In most situations, nonoperative management (NOM) has become the gold standard with the surgeon leading the multidisciplinary treatment [5].


Assuntos
Traumatismos Abdominais , Ferimentos não Penetrantes , Humanos , Criança , Adolescente , Estudos Retrospectivos , Baço/lesões , Acidentes de Trânsito , Cintos de Segurança/efeitos adversos , Traumatismos Abdominais/diagnóstico , Traumatismos Abdominais/terapia , Traumatismos Abdominais/etiologia , Ferimentos não Penetrantes/diagnóstico , Ferimentos não Penetrantes/terapia , Ferimentos não Penetrantes/etiologia
7.
Pediatr Surg Int ; 39(1): 191, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37140693

RESUMO

PURPOSE: Preoperative evaluation of Image Defined Risk Factors (IDRFs) in neuroblastoma (NB) is crucial for determining suitability for upfront resection or tumor biopsy. IDRFs do not all carry the same weighting in predicting tumor complexity and surgical risk. In this study we aimed to assess and categorize a surgical complexity (Surgical Complexity Index, SCI) in NB resection. METHODS: A panel of 15 surgeons was involved in an electronic Delphi consensus survey to identify and score a set of shared items predictive and/or indicative of surgical complexity, including the number of preoperative IDRFs. A shared agreement included the achievement of at least 75% consensus focused on a single or two close risk categories. RESULTS: After 3 Delphi rounds, agreement was established on 25/27 items (92.6%). A severity score was established for each item ranging from 0 to 3 with an overall SCI range varying from a minimum score of zero to a maximum score of 29 points for any given patient. CONCLUSIONS: A consensus on a SCI to stratify the risks related to neuroblastoma tumor resection was established by the panel experts. This index will now be deployed to critically assign a better severity score to IDRFs involved in NB surgery.


Assuntos
Neuroblastoma , Humanos , Neuroblastoma/cirurgia , Neuroblastoma/patologia , Fatores de Risco , Cuidados Pré-Operatórios , Biópsia
8.
Phys Rev Lett ; 129(11): 114801, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36154426

RESUMO

Premature relativistic transparency of ultrathin, laser-irradiated targets is recognized as an obstacle to achieving a stable radiation pressure acceleration in the "light sail" (LS) mode. Experimental data, corroborated by 2D PIC simulations, show that a few-nm thick overcoat surface layer of high Z material significantly improves ion bunching at high energies during the acceleration. This is diagnosed by simultaneous ion and neutron spectroscopy following irradiation of deuterated plastic targets. In particular, copious and directional neutron production (significantly larger than for other in-target schemes) arises, under optimal parameters, as a signature of plasma layer integrity during the acceleration.

9.
Rev Sci Instrum ; 93(5): 053303, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35649771

RESUMO

Image plates (IPs) are a popular detector in the field of laser driven ion acceleration, owing to their high dynamic range and reusability. An absolute calibration of these detectors to laser-driven protons in the routinely produced tens of MeV energy range is, therefore, essential. In this paper, the response of Fujifilm BAS-TR IPs to 1-40 MeV protons is calibrated by employing the detectors in high resolution Thomson parabola spectrometers in conjunction with a CR-39 nuclear track detector to determine absolute proton numbers. While CR-39 was placed in front of the image plate for lower energy protons, it was placed behind the image plate for energies above 10 MeV using suitable metal filters sandwiched between the image plate and CR-39 to select specific energies. The measured response agrees well with previously reported calibrations as well as standard models of IP response, providing, for the first time, an absolute calibration over a large range of proton energies of relevance to current experiments.

10.
Phys Rev Lett ; 128(11): 115101, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35363004

RESUMO

Streaming cosmic rays can power the exponential growth of a seed magnetic field by exciting a nonresonant instability that feeds on their bulk kinetic energy. By generating the necessary turbulent magnetic field, it is thought to play a key role in the confinement and acceleration of cosmic rays at shocks. In this Letter we present hybrid-particle-in-cell simulations of the nonresonant mode including Monte Carlo collisions, and investigate the interplay between the pressure anisotropies produced by the instability and particle collisions in the background plasma. Simulations of poorly ionized plasmas confirm the rapid damping of the instability by proton-neutral collisions predicted by linear fluid theory calculations. In contrast we find that Coulomb collisions in fully ionized plasmas do not oppose the growth of the magnetic field, but under certain conditions suppress the pressure anisotropies and actually enhance the magnetic field amplification.

12.
Eur J Surg Oncol ; 48(1): 283-291, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34489122

RESUMO

INTRODUCTION: Surgery plays a key role in the management of Neuroblastic tumours (NB), where the standard approach is open surgery, while minimally invasive surgery (MIS) may be considered an option in selected cases. The indication(s) and morbidity of MIS remain undetermined due to small number of reported studies. The aim of this study was to critically address the contemporary indications, morbidity and overall survival (OS) and propose guidelines exploring the utility of MIS for NB. MATERIALS & METHODS: A SIOPEN study where data of patients with NB who underwent MIS between 2005 and 2018, including demographics, tumour features, imaging, complications, follow up and survival, were extracted and then analysed. RESULTS: A total of 222 patients from 16 centres were identified. The majority were adrenal gland origin (54%) compared to abdominal non-adrenal and pelvic (16%) and thoracic (30%). Complete and near complete macroscopic resection (>95%) was achieved in 95%, with 10% of cases having conversion to open surgery. Complications were reported in 10% within 30 days of surgery. The presence of IDRF (30%) and/or tumour volume >75 ml were risk factors for conversion and complications in multivariate analysis. Overall mortality was 8.5%. CONCLUSIONS: MIS for NB showed that it is a secure approach allowing more than 95% resection. The presence of IDRFs was not an absolute contraindication for MIS. Conversion to open surgery and overall complication rates were low, however they become significant if tumour volume >75 mL. Based on these data, we propose new MIS guidelines for neuroblastic tumours.


Assuntos
Neoplasias Abdominais/cirurgia , Neoplasias das Glândulas Suprarrenais/cirurgia , Ganglioneuroblastoma/cirurgia , Ganglioneuroma/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Neuroblastoma/cirurgia , Neoplasias Pélvicas/cirurgia , Neoplasias Torácicas/cirurgia , Neoplasias Abdominais/patologia , Neoplasias das Glândulas Suprarrenais/patologia , Criança , Pré-Escolar , Conversão para Cirurgia Aberta , Feminino , Ganglioneuroblastoma/patologia , Ganglioneuroma/patologia , Humanos , Lactente , Masculino , Neuroblastoma/patologia , Neoplasias Pélvicas/patologia , Guias de Prática Clínica como Assunto , Neoplasias Torácicas/patologia , Carga Tumoral
13.
Rev Sci Instrum ; 92(11): 113303, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34852516

RESUMO

The advent of multi-PW laser facilities world-wide opens new opportunities for nuclear physics. With this perspective, we developed a neutron counter taking into account the specifics of a high-intensity laser environment. Using GEANT4 simulations and prototype testings, we report on the design of a modular neutron counter based on boron-10 enriched scintillators and a high-density polyethylene moderator. This detector has been calibrated using a plutonium-beryllium neutron source and commissioned during an actual neutron-producing laser experiment at the LULI2000 facility (France). An overall efficiency of 4.37(59)% has been demonstrated during calibration with a recovery time of a few hundred microseconds after laser-plasma interaction.

14.
Radiologe ; 61(7): 619-628, 2021 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-34143242

RESUMO

CLINICAL/METHODOLOGICAL ISSUE: Renal tumors in children are treated according to the guidelines of the Renal Tumor Study Group of the International Society of Pediatric Oncology (SIOP-RTSG). Nephroblastoma is the most frequent renal tumor in children. STANDARD RADIOLOGICAL METHODS: After sonography, magnetic resonance imaging (MRI) is the preferred imaging modality. The task of imaging includes differential diagnosis with the help of morphological and epidemiological criteria. Thorax computed tomography (CT) is introduced for initial staging. METHODOLOGICAL INNOVATIONS: Current studies of diffusion-weighted imaging (DWI)-MRI with analysis of the apparent diffusion coefficient (ADC) histogram indicate the potential to differentiate blastemal or anaplastic high-risk histology nephroblatoma subtypes. Imaging criteria for nephron-sparing surgery are defined and allow an individual therapy option in unilateral and especially in bilateral renal nephroblastoma. PERFORMANCE: In addition to nephroblastoma, the differential diagnosis includes congenital mesoblastic nephroma, malignant rhabdoid tumor of the kidney, clear cell sarcoma and renal cell carcinoma. The diagnosis of nephrogenic rests and nephroblastomatosis is challenging. ACHIEVEMENTS: Diagnostic standardization improves diagnosis and therapy of renal childhood tumors, and new prognostic markers may be introduced in the near future.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Tumor de Wilms , Criança , Humanos , Rim , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/cirurgia , Nefrectomia , Tumor de Wilms/diagnóstico por imagem , Tumor de Wilms/cirurgia
15.
Int J Biometeorol ; 65(7): 1151-1160, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33649972

RESUMO

Multimodal therapies comprising spa applications are widely used as non-pharmaceutical treatment options for musculoskeletal diseases. The purpose of this randomized, controlled, open pilot study was to elucidate the involvement of the endocannabinoid system in a multimodal therapy approach. Twenty-five elderly patients with knee osteoarthritis (OA) received a 2-week spa therapy with or without combination of low-dose radon therapy in the Bad Gastein radon gallery. A 10-point numerical rating scale (pain in motion and at rest), WOMAC questionnaire, and the EuroQol-5D (EQ-5D) questionnaire were recorded at baseline, and during treatment period at weeks one and two, and at 3-month and 6-month follow-ups. Plasma levels of the endocannabinoid anandamide (AEA) were determined at baseline and at 2 weeks, and serum levels of several cartilage metabolism markers at all five time-points. A significant and sustained reduction of self-reported knee pain was observed in the study population, but no further significant effect of the additional radon therapy up and above base therapy. This pain reduction was accompanied by a significant reduction of AEA plasma levels during treatment in both groups. No significant differences were seen in serum marker concentrations between the groups treated with or without radon, but a small reduction of serum cartilage degradation markers was observed during treatment in both groups. This is the first study investigating AEA levels in the context of a non-pharmacological OA treatment. Since the endocannabinoid system represents a potential target for the development of new therapeutics, further studies will have to elucidate its involvement in OA pain.


Assuntos
Osteoartrite do Joelho , Radônio , Idoso , Ácidos Araquidônicos , Terapia Combinada , Endocanabinoides , Humanos , Osteoartrite do Joelho/terapia , Dor , Projetos Piloto , Alcamidas Poli-Insaturadas , Radônio/uso terapêutico , Autorrelato , Resultado do Tratamento
16.
Nat Commun ; 12(1): 762, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536408

RESUMO

The shaping of astrophysical outflows into bright, dense, and collimated jets due to magnetic pressure is here investigated using laboratory experiments. Here we look at the impact on jet collimation of a misalignment between the outflow, as it stems from the source, and the magnetic field. For small misalignments, a magnetic nozzle forms and redirects the outflow in a collimated jet. For growing misalignments, this nozzle becomes increasingly asymmetric, disrupting jet formation. Our results thus suggest outflow/magnetic field misalignment to be a plausible key process regulating jet collimation in a variety of objects from our Sun's outflows to extragalatic jets. Furthermore, they provide a possible interpretation for the observed structuring of astrophysical jets. Jet modulation could be interpreted as the signature of changes over time in the outflow/ambient field angle, and the change in the direction of the jet could be the signature of changes in the direction of the ambient field.

17.
Sci Adv ; 7(2)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33523995

RESUMO

Human adenovirus (HAdV) types F40 and F41 are a prominent cause of diarrhea and diarrhea-associated mortality in young children worldwide. These enteric HAdVs differ notably in tissue tropism and pathogenicity from respiratory and ocular adenoviruses, but the structural basis for this divergence has been unknown. Here, we present the first structure of an enteric HAdV-HAdV-F41-determined by cryo-electron microscopy to a resolution of 3.8 Å. The structure reveals extensive alterations to the virion exterior as compared to nonenteric HAdVs, including a unique arrangement of capsid protein IX. The structure also provides new insights into conserved aspects of HAdV architecture such as a proposed location of core protein V, which links the viral DNA to the capsid, and assembly-induced conformational changes in the penton base protein. Our findings provide the structural basis for adaptation of enteric HAdVs to a fundamentally different tissue tropism.

18.
Rev Sci Instrum ; 92(12): 123506, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34972475

RESUMO

An up to 15 T pulsed magnetic field generator in a volume of a few cubic centimeters has been developed for experiments with magnetized laser plasma. The magnetic field is created by a pair of coils placed in a sealed reservoir with liquid nitrogen, installed in a vacuum chamber with a laser target. The bearing body provides the mechanical strength of the system both in the case of co-directional and oppositely connected coils. The configuration of the housing allows laser radiation to be introduced into the working area between the coils in a wide range of directions and focusing angles, places targets away from the symmetry axis of the magnetic system, and irradiates several targets simultaneously.

19.
Chromosoma ; 129(3-4): 285-297, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33165742

RESUMO

For a long time, the Cyperid clade (Thurniceae-Juncaceae-Cyperaceae) was considered a group of species possessing holocentromeres exclusively. The basal phylogenetic position of Prionium serratum (Thunb.) Drège (Thurniceae) within Cyperids makes this species an important specimen to understand the centromere evolution within this clade. In contrast to the expectation, the chromosomal distribution of the centromere-specific histone H3 (CENH3), alpha-tubulin and different centromere-associated post-translational histone modifications (H3S10ph, H3S28ph and H2AT120ph) demonstrate a monocentromeric organisation of P. serratum chromosomes. Analysis of the high-copy repeat composition resulted in the identification of two centromere-localised satellite repeats. Hence, monocentricity was the ancestral condition for the Juncaceae-Cyperaceae-Thurniaceae Cyperid clade, and holocentricity in this clade has independently arisen at least twice after differentiation of the three families, once in Juncaceae and the other one in Cyperaceae. In this context, methods suitable for the identification of holocentromeres are discussed.


Assuntos
Cromossomos de Plantas , Cyperaceae/classificação , Cyperaceae/genética , Filogenia , Centrômero/genética , DNA Satélite , Genoma de Planta , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Hibridização in Situ Fluorescente , Proteínas de Plantas/genética
20.
Semin Pediatr Surg ; 29(4): 150941, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32861445

RESUMO

Benign liver tumors in children are far less frequent than their malignant counterparts. Recently, there have been advances of diagnostic procedures and novel treatments with improved classification as a result. While malignant pediatric liver tumors have been comprehensively addressed by multicenter international tumor trials, benign tumors have more usually relied upon individualised workup and treatment. Due to the rarity and heterogeneity of these different entities, large studies are lacking. In this article the authors highlight the spectrum of benign liver tumors with special focus on specific clinical features, pathology, and treatment.


Assuntos
Adenoma/terapia , Hiperplasia Nodular Focal do Fígado/terapia , Hamartoma/terapia , Hemangioma/terapia , Neoplasias Hepáticas/terapia , Adenoma/patologia , Adenoma/fisiopatologia , Criança , Hiperplasia Nodular Focal do Fígado/patologia , Hiperplasia Nodular Focal do Fígado/fisiopatologia , Hamartoma/patologia , Hamartoma/fisiopatologia , Hemangioma/patologia , Hemangioma/fisiopatologia , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/fisiopatologia
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