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1.
J Phys Condens Matter ; 36(42)2024 Jul 22.
Article in English | MEDLINE | ID: mdl-38830374

ABSTRACT

In addition to spin angular momentum, light can carry orbital angular momentum. The orbital angular momentum degree of freedom in the extreme ultraviolet and x-ray regimes enables fundamental studies of light-matter interactions and new methods to study materials. Advances in x-ray optics, as well as undulator radiation and high harmonic generation techniques, lead to the creation of beams with non-trivial phase structure, such as a helical phase structure, creating new possibilities for the use of extreme ultraviolet and x-ray photons with orbital angular momentum in probing complex electronic structures in matter. In this article, we review the generation and applications of orbital angular momentum beams in the x-ray and extreme ultraviolet regime. We discuss several recent works that exploit the orbital angular momentum degree of freedom and showcase the potential advantages of using these beams.

2.
Rev. argent. cir ; 116(2): 122-133, jun. 2024. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1565217

ABSTRACT

RESUMEN Antecedentes: las cirugías abdominales mayores pueden presentar complicaciones posoperatorias graves cuya detección temprana resulta importante para su tratamiento. Objetivo: determinar la utilidad del uso de la tomografía computarizada (TC) para el diagnóstico temprano de las complicaciones de cirugía abdominal mayor. Materiales y métodos: estudio retrospectivo observacional descriptivo, mediante revisión de historias clínicas de pacientes operados de cirugía abdominal mayor en un Hospital Privado. Se agruparon los pacientes según presentaban o no síntomas sospechosos de complicación posoperatoria. Los primeros se clasificaron en 3 grupos: sin TC, con TC con hallazgos positivos y con TC sin hallazgos patológicos. Resultados: se analizaron 154 pacientes, con un promedio de edad de 61,3 ± 12,5 años; 83 (54%) fueron varones. Sobre 48 pacientes (31%) con síntomas sospechosos de complicaciones, fueron reoperados 6 sin TC, pero con síntomas muy evidentes, 7 con signos tomográficos positivos y 14/41 del grupo con TC negativa. Todos tuvieron hallazgos que justificaron la intervención. Hubo 27 casos (17,5%) con complicaciones IIIb según Clavien-Dindo y 3 pacientes (2%) fallecieron. Conclusión: la tomografía computarizada tuvo valor para confirmar una complicación, pero no para descartarla. Los parámetros clínicos cobran especial importancia en los pacientes sintomáticos sin hallazgos patológicos en la TC posoperatoria.


ABSTRACT Background: Major abdominal surgeries may present serious postoperative complications that require early diagnosis. Objective: The aim of this study was to determine the usefulness of computed tomography (CT) for the early diagnosis of major abdominal surgery complications. Material and methods: We conducted a retrospective, observational and descriptive study using data obtained from the medical records of patients undergoing major abdominal surgery in a private hospital. Patients were divided into two groups according to the presence or absence of symptoms suggesting a postoperative complication. Patients with symptoms were classified into 3 groups: without CT, with CT with positive findings and with CT without abnormal findings. Results: A total of 154 patients were analyzed; mean age was 61.3 ± 12.5 years and 83 (54%) were male. Of 48 patients (31%) with symptoms suggestive of complications, 6 had very evident symptoms and were re-operated without CT, 7 had positive findings on CT and CT was negative in 14/41. All the patients had findings that supported the decision to re-operate. There were 27 cases (17.5%) with grade 3b complications of the Clavien-Dindo classification and 3 patients (2%) died. Conclusion: Computed tomography was useful to confirm a complication, but not to rule it out. Clinical parameters remain of utmost importance in patients with symptoms and absence of abnormal findings in post-operative CT.

3.
Adv Mater ; 36(29): e2401742, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38635929

ABSTRACT

Cellulose-based nanocomposites are highly appealing for the development of next-generation sustainable functional materials. Although many advances have been made in this direction, the true potential of fibrillar nanocomposites has yet to be realized because available fabrication approaches are inadequate for achieving precise structural control at the sub-micrometer scale. Here a spray-assisted alignment methodology of cellulose nanofibrils is combined with the layer-by-layer assembly into an additive manufacturing process in which the alignment direction of each cellulose layer is rationally selected to achieve thin films with a helicoidal arrangement of the nanofibrils. The helicoidal structure of the films is verified by measuring the circular dichroism (CD) of the samples. The sign and position of the structural CD peak show that the handedness and the pitch of the chiral structures can be easily tuned by deliberately selecting simple parameters, such as the number of consecutive cellulose layers sprayed in the same direction, and the angle of rotation between successive stacks of layers. To the authors' knowledge, this approach is unique as it offers the possibility to prepare complex nanocomposite architectures with various nanoscale-controlled sub-structures from different anisometric objects, which is enabling novel designs of composite films with damage-resistant and/or optical filtering functionalities.

4.
Front Plant Sci ; 15: 1358974, 2024.
Article in English | MEDLINE | ID: mdl-38559764

ABSTRACT

Sexual reproduction of Zygnematophyceae by conjugation is a less investigated topic due to the difficulties of the induction of this process and zygospore ripening under laboratory conditions. For this study, we collected field sampled zygospores of Spirogyra mirabilis and three additional Spirogyra strains in Austria and Greece. Serial block-face scanning electron microscopy was performed on high pressure frozen and freeze substituted zygospores and 3D reconstructions were generated, allowing a comprehensive insight into the process of zygospore maturation, involving storage compound and organelle rearrangements. Chloroplasts are drastically changed, while young stages contain both parental chloroplasts, the male chloroplasts are aborted and reorganised as 'secondary vacuoles' which initially contain plastoglobules and remnants of thylakoid membranes. The originally large pyrenoids and the volume of starch granules is significantly reduced during maturation (young: 8 ± 5 µm³, mature: 0.2 ± 0.2 µm³). In contrast, lipid droplets (LDs) increase significantly in number upon zygospore maturation, while simultaneously getting smaller (young: 21 ± 18 µm³, mature: 0.1 ± 0.2 and 0.5 ± 0.9 µm³). Only in S. mirabilis the LD volume increases (34 ± 29 µm³), occupying ~50% of the zygospore volume. Mature zygospores contain barite crystals as confirmed by Raman spectroscopy with a size of 0.02 - 0.05 µm³. The initially thin zygospore cell wall (~0.5 µm endospore, ~0.8 µm exospore) increases in thickness and develops a distinct, electron dense mesospore, which has a reticulate appearance (~1.4 µm) in Spirogyra sp. from Greece. The exo- and endospore show cellulose microfibrils in a helicoidal pattern. In the denser endospore, pitch angles of the microfibril layers were calculated: ~18 ± 3° in S. mirabilis, ~20 ± 3° in Spirogyra sp. from Austria and ~38 ± 8° in Spirogyra sp. from Greece. Overall this study gives new insights into Spirogyra sp. zygospore development, crucial for survival during dry periods and dispersal of this genus.

5.
Adv Mater ; 36(24): e2311785, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38456592

ABSTRACT

Metasurfaces are flat arrays of nanostructures that allow exquisite control of phase and amplitude of incident light. Although metasurfaces offer new active element for both fundamental science and applications, the challenge still remains to overcome their low information capacity and passive nature. Here, by integrating an inverse-designed-metasurface with oblique helicoidal cholesteric liquid crystal (ChOH), simultaneous spatial and spectral tunable metasurfaces with a high information capacity for dynamic hyperspectral holography, are demonstrated. The inverse design facilitates a single-phase map encoding of ten independent holographic images at different wavelengths. ChOH provides precise spectral modulation with narrow bandwidth and wide tunable regime in response to programmed stimuli, thus enabling dynamic switching of the multicolor holography. The results provide simple and generalizable principles for the rational design of interactive metasurfaces that will find numerous applications, including security platform.

6.
Alerta (San Salvador) ; 7(1): 36-41, ene. 26, 2024. ilus, tab.
Article in Spanish | BISSAL, LILACS | ID: biblio-1526699

ABSTRACT

Presentación del caso. Se trata de una mujer de 26 años que presentó dolor en epigastrio e hipocondrio izquierdo, con aumento del perímetro abdominal y pérdida de 5 kg de peso corporal. En el examen físico se detectó una masa de gran tamaño en el epigastrio, con bordes regulares, ligeramente dolorosa al tacto y no móvil. Los estudios de imagen revelaron una neoplasia mixta en el cuerpo y cola pancreática. Intervención terapéutica. Se practicó una esplenopancreatectomía corpo-caudal, con extirpación completa del tumor. Evolución clínica. La paciente recibió cuidados especializados y vigilancia estrecha posquirúrgica en la unidad de cuidados intensivos, sin presentar complicaciones relevantes. Tras el alta hospitalaria, la paciente refirió un buen estado general en los controles de seguimiento, que incluyeron una tomografía realizada a los 12 meses, donde no se evidenciaron restos o recidivas tumorales


Case presentation. A 26-year-old woman who presented with pain in the epigastrium and left hypochondrium, with increased abdominal perimeter and loss of 5 kg of body weight. Physical examination revealed a large mass in the epigastrium, with regular borders, slightly painful to the touch and non-mobile. Imaging studies revealed a mixed neoplasm in the pancreatic body and tail. Treatment. A corpo-caudal splenopancreatectomy was performed, with complete removal of the tumor. Outcome. The patient received specialized care and close postoperative surveillance in the intensive care unit, with no relevant complications. After hospital discharge, the patient reported a good general condition in the follow-up controls, which included a computed tomography scan performed after 12 months, where no tumor remnants or recurrences were evidenced


Subject(s)
Humans , Female , Adult , El Salvador
7.
Bioinspir Biomim ; 18(5)2023 08 14.
Article in English | MEDLINE | ID: mdl-37531970

ABSTRACT

Many living organisms exhibit exceptional capabilities and have evolved effective strategies to synthesize impact-resistant and damage-tolerant structures. One such example can be observed in the rapid mandible strikes ofOdontomachus monticola, a species of trap-jaw ants from the ponerine subfamily. During trap-jaw strikes, the mandibles can achieve peak speeds of 35.42 m s-1, and the maximum acceleration can reach 71 729 g within an average duration of 0.18 ms. The extreme acceleration results in instantaneous mandible strike forces that can exceed 330 times the ant's body weight, withstanding thousands of impacts. A natural impact-resistant fibrous helicoidal structure is found in the mandibles of trap-jaw ants. This microstructure is characterized by periodic modulus oscillations that increase energy absorption and improve stress redistribution, offering added protection against damage from impact loading. A carbon fiber reinforced helicoidal composite is fabricated based on the microstructure of the trap-jaw ant's mandibles. The results show that the helicoidal composite with a 12° helical-fiber exhibits higher residual strength, making it more capable of withstanding strong collisions. The catastrophic propagation of damage along the thickness direction is prevented by in-plane spreading and redirection of cracks. This research provides useful references for fabricating bionic impact-resistant composites.


Subject(s)
Ants , Animals , Bionics , Mandible , Body Weight , Carbon Fiber
8.
Materials (Basel) ; 16(13)2023 Jun 26.
Article in English | MEDLINE | ID: mdl-37444913

ABSTRACT

The helicoidal laminate is a kind of nature inspired fiber reinforced polymer, and the ply orientation affects their mechanical properties for engineering structural applications. A variety of helicoidal laminates with uniform and non-linear pitch angles mixed with additional 0° plies are fabricated to investigate the impact resistance through low-velocity impact and after-impact compression tests. Additionally, helicoidal laminates with constant pitch angles, quasi-isotropic laminate, and cross-ply laminates are also fabricated for a comparative study. The impact characteristics and the compressive strength are analyzed in view of the impact model, shear stress distribution, and fracture toughness. The results suggest that 10° or 20° are the better basic pitch angles before mixing 0° orientation plies. The 0° orientation plies may affect the contact stiffness, bending stiffness, damage extent, and compressive modulus. The compressive strength reaches the highest in tests on two samples with different percentages of 0° orientation plies and ply setups. Bending stiffness also dominates the impact response. The analysis on the laminate parameters provides ideas to improve the residual strength of helicoidal laminate.

9.
Acta Biomater ; 169: 179-191, 2023 10 01.
Article in English | MEDLINE | ID: mdl-37517616

ABSTRACT

The majority of living organisms demonstrate remarkable attributes and have evolved effective mechanisms for synthesizing impact-resistant and damage-tolerant structures. One exemplary instance is the rapid mandible strikes exhibited by trap-jaw ants, which are a highly aggressive species of terrestrial social organisms. An impact-resistant sinusoidal helicoidal architecture is discovered in the mandibles of trap-jaw ants. The bioinspired laminate with a bi-sinusoidal helicoidal structure was manufactured using unidirectional carbon fiber prepreg by mold press forming. This study examines the impact resistance and damage tolerance of a bionic laminate through low velocity impact, computed tomography, and compression after impact tests. The results demonstrate that bionic laminates effectively limit damage propagation within the plane while enhancing energy dissipation capacity. The sinusoidal helicoidal configuration enhances cushioning capability against impact forces, retards penetration under higher loads, hinders crack propagation, and improves residual strength. Bionic laminates provide a valuable solution for damage tolerance through the resistance to through-the-thickness loads. STATEMENT OF SIGNIFICANCE: Helicoidal and sinusoidal helicoidal microstructures have been identified in the cross-section of the jaws of trap-jaw ants. The multiple waviness ratio parameters are designed for fabricating a sinusoidal helicoidal structure laminate using unidirectional carbon fiber prepreg through the mold press forming technique. This results in a damage-tolerant mechanism characterized by reduced delamination damage, which leads to a stiffer mechanical response. Meanwhile, it enhances resistance to crack propagation, leading to the formation of discontinuous delamination areas and the accumulation of sub-critical failures. Additionally, the sinusoidal helicoidal structure laminate combines the cushioning performance of bi-sinusoidal arrangements with the enhanced impact resistance of helical arrangements. This design delays penetration at higher loads, resulting in increased residual strength.


Subject(s)
Ants , Animals , Carbon Fiber , Ants/physiology , Jaw , Mandible
10.
J Mech Behav Biomed Mater ; 142: 105866, 2023 06.
Article in English | MEDLINE | ID: mdl-37141743

ABSTRACT

The rotation angle is an important parameter affecting the performance of helical structures, and helical structures with nonlinearly increasing rotation angles have been studied. The fracture behavior of a 3D-printed helicoidal recursive (HR) composite with nonlinear rotation angle-based layups was investigated by performing quasistatic three-point bending experiments and simulations. First, the crack propagation paths during the loading of the samples were observed, and the critical deformation displacements and fracture toughness were calculated. It was found that the crack path that propagated along the soft phase increased the critical failure displacement and toughness of the samples. Then, the deformation and interlayer stress distribution of the helical structure under static loading were obtained by finite element simulation. The results showed that the variation in the rotation angle between the layers caused different degrees of shear deformation at the interface between adjacent layers, resulting in different shear stress distributions and thus different crack modes of the HR structures. The mixed-mode I + II cracks induced crack deflection, which slowed the eventual failure of the sample and improved the fracture toughness.


Subject(s)
Fractures, Bone , Humans , Rotation , Stress, Mechanical , Computer Simulation
11.
Chemosphere ; 333: 138961, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37207900

ABSTRACT

Immobilization of metal-organic frameworks (MOFs) on electrospun products for wastewater treatment has garnered considerable attention in recent years. However, the effect of the overall geometry and surface-area-to-volume ratio of MOF-decorated electrospun architectures on their performances have rarely been investigated. Herein, we prepared polycaprolactone (PCL)/polyvinylpyrrolidone (PVP) strips with helicoidal geometries via immersion electrospinning. By regulating the weight ratio of PCL to PVP, the morphologies and surface-area-to-volume ratios of the PCL/PVP strips could be controlled precisely. Then, the zeolitic imidazolate framework-8 (ZIF-8) for removing methylene blue (MB) from an aqueous solution was immobilized on the electrospun strips, resulting in ZIF-8-decorated PCL/PVP strips. The key characteristics of these composite products, such as adsorption and photocatalytic degradation behavior toward MB in the aqueous solution, were carefully investigated. Owing to the desired overall geometry and high surface-area-to-volume ratio of the ZIF-8-decorated helicoidal strips, a high MB adsorption capacity of 151.6 mg g-1 was obtained, which is significantly higher than those with conventional electrospun straight fibers. In addition, higher MB uptake rates, higher recycling and kinetic adsorption efficiencies, higher MB photocatalytic degradation efficiencies, and faster MB photocatalytic degradation rates were confirmed. This work provides new insights to improve the performance of existing and potential electrospun product-based water treatment strategies.


Subject(s)
Metal-Organic Frameworks , Zeolites , Polymers , Methylene Blue , Povidone , Adsorption
12.
Cancer Radiother ; 27(4): 267-272, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37179220

ABSTRACT

PURPOSE: Helical tomotherapy (HT) is a rotational intensity-modulated radiation therapy (IMRT) technique that allows target conformal irradiation and efficient organs at risk (OAR) sparing in the case of complex target volumes and specific anatomic considerations, but increases the "low-dose bath" to non-target volumes. The aim of this study was to analyze the delayed hepatotoxicity after rotational IMRT (HT) radiation therapy for non-metastatic breast cancer. PATIENTS AND METHODS: This single-center retrospective study included all non-metastatic breast cancer patients with a normal pre-radiotherapy biological hepatic function who were treated with tomotherapy between January 2010 and January 2021 and for whom the dosimetric parameters for the whole liver were assessable. A logistic regression analysis was employed. The selected covariates for the multivariate analysis were those with a P-value that was less or equal to 0.20 in the univariate analysis. RESULTS: Forty-nine patients were included in this study: 11 patients (22%) received Trastuzumab for 1 year in tumors with an HER2-expression; 27 patients (55%) received radiation therapy for cancer of the right or bilateral breasts; 43 patients (88%) received lymph node irradiation and 41 patients (84%) received a tumor bed boost. Mean and maximum doses to the liver were 2.8Gy [0.3-16.6] and 26.9Gy [0.7-51.7], respectively. With a median follow-up after irradiation was 5.4 years (range, 6 to 115 months), 11 patients (22%) had developed delayed low grade biological hepatic abnormalities: all patients had grade 1 delayed hepatotoxicity; 3 patients (6%) had additional grade 2 delayed hepatotoxicity. There was no hepatotoxicity at grade 3 or higher. According to the univariate and multivariate analysis, Trastuzumab was a significant predictive variable of late biological hepatotoxicity (OR=4.4 [1.01-20.18], P=0.04). No other variable was statistically associated with delayed biological hepatotoxicity. CONCLUSION: Delayed hepatotoxicity after multimodal non-metastatic breast cancer management including rotational IMRT was negligible. Consequently, the liver doesn't have to be considered like an organ-at-risk in the analysis of breast cancer radiotherapy but future prospectives studies are needed to confirm these findings.


Subject(s)
Breast Neoplasms , Radiotherapy, Intensity-Modulated , Humans , Female , Radiotherapy, Intensity-Modulated/adverse effects , Radiotherapy, Intensity-Modulated/methods , Breast Neoplasms/radiotherapy , Breast Neoplasms/etiology , Retrospective Studies , Organ Sparing Treatments , Radiotherapy Dosage , Organs at Risk , Trastuzumab , Radiotherapy Planning, Computer-Assisted
13.
Bioengineering (Basel) ; 10(2)2023 Feb 17.
Article in English | MEDLINE | ID: mdl-36829760

ABSTRACT

Myocardium consists of cardiac cells that interact with their environment through physical, biochemical, and electrical stimulations. The physiology, function, and metabolism of cardiac tissue are affected by this dynamic structure. Within the myocardium, cardiomyocytes' orientations are parallel, creating a dominant orientation. Additionally, local alignments of fibers, along with a helical organization, become evident at the macroscopic level. For the successful development of a reliable in vitro cardiac model, evaluation of cardiac cells' behavior in a dynamic microenvironment, as well as their spatial architecture, is mandatory. In this study, we hypothesize that complex interactions between long-term contraction boundary conditions and cyclic mechanical stimulation may provide a physiological mechanism to generate off-axis alignments in the preferred mechanical stretch direction. This off-axis alignment can be engineered in vitro and, most importantly, mirrors the helical arrangements observed in vivo. For this purpose, uniaxial mechanical stretching of dECM-fibrin hydrogels was performed on pre-aligned 3D cultures of cardiac cells. In view of the potential development of helical structures similar to those in native hearts, the possibility of generating oblique alignments ranging between 0° and 90° was explored. Indeed, our investigations of cell alignment in 3D, employing both mechanical stimulation and groove constraint, provide a reliable mechanism for the generation of helicoidal structures in the myocardium. By combining cyclic stretch and geometric alignment in grooves, an intermediate angle toward favored direction can be achieved experimentally: while cyclic stretch produces a perpendicular orientation, geometric alignment is associated with a parallel one. In our 2D and 3D culture conditions, nonlinear cellular addition of the strains and strain avoidance concept reliably predicted the preferred cellular alignment. The 3D dECM-fibrin model system in this study shows that cyclical stretching supports cell survival and development. Using mechanical stimulation of pre-aligned heart cells, maturation markers are augmented in neonatal cardiomyocytes, while the beating culture period is prolonged, indicating an improved model function. We propose a simplified theoretical model based on numerical simulation and nonlinear strain avoidance by cells to explain oblique alignment angles. Thus, this work lays a possible rational basis for understanding and engineering oblique cellular alignments, such as the helicoidal layout of the heart, using approaches that simultaneously enhance maturation and function.

14.
Polymers (Basel) ; 15(23)2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38231997

ABSTRACT

Characterized by light weight and high strength, composites are widely used as protective materials in dynamic impact loading under extreme conditions, such as high strain rates. Therefore, based on the excellent tensile properties of continuous fiber and the good flexibility and toughness of the bionic spiral structure, this study uses a multi-material 3D printer to incorporate continuous fiber, and then modifies the G-CODE file to control the printing path to achieve the production of a continuous fiber-reinforced Polylactic Acid composite helicoidal (spiral angle 60°) structure (COF-HP). Dynamic behavior under high-strain-rate impact experiments have been conducted using the Split Hopkinson Pressure Bar (SHPB). Stress-strain curves, impact energy curves and high-speed camera photographs with different strain rates at 680 s-1 and 890 s-1 have been analyzed to explore the dynamic process and illustrate the damage evolution. In addition, some detailed simulation models considering the incorporation of continuous optical fiber (COF) and different strain rates have been established and verified for deeper investigations. The results show that the COF does enhance the impact resistance of the laminates. When the porosity is reduced, the maximum stress of the continuous fiber-reinforced composite material is 4~7% higher than that of the pure PLA material. Our findings here expand the application of COF and provide a new method for designing protective materials, which have broad application prospects in the aerospace and automotive industries.

15.
Front Plant Sci ; 13: 1080111, 2022.
Article in English | MEDLINE | ID: mdl-36561459

ABSTRACT

Zygnematophyceae, a class of streptophyte green algae and sister group to land plants (Embryophytes) live in aquatic to semi-terrestrial habitats. The transition from aquatic to terrestrial environments requires adaptations in the physiology of vegetative cells and in the structural properties of their cell walls. Sexual reproduction occurs in Zygnematophyceae by conjugation and results in the formation of zygospores, possessing unique multi-layered cell walls, which might have been crucial in terrestrialization. We investigated the structure and chemical composition of field sampled Spirogyra sp. zygospore cell walls by multiple microscopical and spectral imaging techniques: light microscopy, confocal laser scanning microscopy, transmission electron microscopy following high pressure freeze fixation/freeze substitution, Raman spectroscopy and atomic force microscopy. This comprehensive analysis allowed the detection of the subcellular organization and showed three main layers of the zygospore wall, termed endo-, meso- and exospore. The endo- and exospore are composed of polysaccharides with different ultrastructural appearance, whereas the electron dense middle layer contains aromatic compounds as further characterized by Raman spectroscopy. The possible chemical composition remains elusive, but algaenan or a sporopollenin-like material is suggested. Similar compounds with a non-hydrolysable character can be found in moss spores and pollen of higher plants, suggesting a protective function against desiccation stress and high irradiation. While the tripartite differentiation of the zygospore wall is well established in Zygnematopyhceae, Spirogyra showed cellulose fibrils arranged in a helicoidal pattern in the endo- and exospore. Initial incorporation of lipid bodies during early zygospore wall formation was also observed, suggesting a key role of lipids in zygospore wall synthesis. Multimodal imaging revealed that the cell wall of the sexually formed zygospores possess a highly complex internal structure as well as aromatics, likely acting as protective compounds and leading to impregnation. Both, the newly discovered special three-dimensional arrangement of microfibrils and the integration of highly resistant components in the cell wall are not found in the vegetative state. The variety of methods gave a comprehensive view on the intricate zygospore cell wall and its potential key role in the terrestrial colonization and plant evolution is discussed.

16.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1559896

ABSTRACT

Introducción: Las fracturas humerales diafisarias multifragmentarias con extensión proximal son patrones infrecuentes de lesión causados principalmente por trauma de alta energía. La forma anatómica del húmero, la presencia de la tuberosidad deltoidea y la proximidad del nervio radial al surco radial representan retos a tratar, por ello se recomiendan incisiones mínimamente invasivas y la estabilización de la fractura con placa proximal humeral internal locking system. Objetivo: Demostrar la eficacia de la técnica minimally invasive plate osteosynthesis con el moldeamiento helicoidal de la placa proximal humeral internal locking system. Presentación del caso: Paciente de 29 años que sufrió accidente de tránsito y presentó fractura diafisaria multifragmentaria extendida al húmero proximal. Se trató con la técnica minimally invasive plate osteosynthesis y placa helicoidal proximal humeral internal locking system. Alcanzó la consolidación completa y rápida recuperación funcional. Conclusiones: La técnica minimally invasive plate osteosynthesis con placa helicoidal proximal humeral internal locking system es una opción quirúrgica eficaz y segura para las fracturas humerales diafisarias multifragmentarias con extensión proximal, ya que preserva la inserción muscular deltoidea, mejora el contacto placa hueso con riesgo mínimo de lesión neurológica axilar y radial, favorece la curación ósea y mejora el resultado funcional.


Introduction: Multifragmentary diaphyseal humeral fractures with proximal extension are infrequent patterns of injury caused mainly by high-energy trauma. The anatomical shape of the humerus, the presence of the deltoid tuberosity and the proximity of the radial nerve to the radial groove represent challenges to be treated, therefore minimally invasive incisions and fracture stabilization with the proximal humeral internal locking system plate are recommended. Objective: To establish the efficacy of the minimally invasive plate osteosynthesis technique with helical molding of the proximal humeral plate internal locking system. Case report: We report the case of a 29-year-old patient who suffered a traffic accident and had a multifragmentary diaphyseal fracture extended to the proximal humerus. He was treated with the minimally invasive plate osteosynthesis technique and the humeral proximal helical plate internal locking system. He achieved complete consolidation and rapid functional recovery. Conclusions: The minimally invasive plate osteosynthesis technique with the humeral proximal helical plate internal locking system is an effective and safe surgical option for multifragmentary diaphyseal humeral fractures with proximal extension, since it preserves the deltoid muscle insertion, improves bone-plate contact with minimal risk of fracture. Axillary and radial neurological injury, promotes bone healing and improves functional outcome.

17.
Methods Mol Biol ; 2494: 25-35, 2022.
Article in English | MEDLINE | ID: mdl-35467198

ABSTRACT

Unable to move, plants are physically restrained to the place where they grow. Remarkably, plants have developed a myriad of mechanisms to perceive the surrounding environment in order to maximize growth and survival. One of those mechanisms is the ability to perceive mechanical stimulus such as touch (thigmomorphogenesis), in order to adjust growth patterns (in different organs) to either attach to or surround an object. Roots are able to perceive several mechanical forces (e.g., gravity, touch). However, being the "hidden part" of a plant, it is difficult to assess their response to mechanical stimulation. In this chapter, our team presents a simple method to evaluate rice (Oryza sativa L.) root mechanosensing response that can be used to test different conditions (e.g., hormones) affecting rice root response to touch stimulus. This method is affordable to any lab and can be upgraded with a fully automated image recording system. We provide a detailed protocol with several notes for a more comprehensive application.


Subject(s)
Oryza , Plant Roots
18.
Cancer Radiother ; 26(5): 654-662, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35227593

ABSTRACT

PURPOSE: Intensity-modulated radiotherapy with helical Tomotherapy is a novel radiation therapy technique, which may be beneficial in several features compared to traditional methods. Our aim was to evaluate the local control, overall survival, progression free survival and adverse events in breast cancer patients treated with this new technique. MATERIAL AND METHODS: This is retrospective analysis of patients irradiated with intensity-modulated radiotherapy with helical Tomotherapy. Overall survival and progression free survival curves were plotted with Kaplan-Meier method. We also analysed the overall survival and progression-free survival data by molecular subgroups. Long-term toxicity including skin, cardiac and pulmonary complications were also evaluated. Multivariant logistic regression analysis was performed to determine the predictors of the side effects. RESULTS: Between 2009-2015, 179 consecutive patients with 194 treated breasts were irradiated with intensity-modulated radiotherapy with helical Tomotherapy. The median follow-up were 65 months. The overall survival rate was 89.2% (95% confidence interval [95CI]: 83.5-95.4%), while disease-free survival rate was 85.4% (95CI: 80.2-91%). The Human epidermal growth factor receptor 2-positive patients had the best 5-year overall survival data of 95% (95CI: 85.9-100%). Long-term skin toxicity was the most common, seen in a total of 20.7% of the patients. CONCLUSION: Intensity-modulated radiotherapy with helical Tomotherapy could be safely used for adjuvant breast cancer irradiation in patients with complex anatomy and provides favourable long-term prognosis with acceptable late toxicity.


Subject(s)
Breast Neoplasms , Radiotherapy, Intensity-Modulated , Breast Neoplasms/drug therapy , Female , Follow-Up Studies , Humans , Radiotherapy Dosage , Radiotherapy, Adjuvant , Radiotherapy, Intensity-Modulated/adverse effects , Radiotherapy, Intensity-Modulated/methods , Retrospective Studies
19.
Polymers (Basel) ; 14(6)2022 Mar 18.
Article in English | MEDLINE | ID: mdl-35335558

ABSTRACT

When silicon solar cells are used in the novel lightweight photovoltaic (PV) modules using a sandwich design with polycarbonate sheets on both the front and back sides of the cells, they are much more prone to impact loading, which may be prevalent in four-season countries during wintertime. Yet, the lightweight PV modules have recently become an increasingly important development, especially for certain segments of the renewable energy markets all over the world-such as exhibition halls, factories, supermarkets, farms, etc.-including in countries with harsh hailstorms during winter. Even in the standard PV module design using glass as the front sheet, the silicon cells inside remain fragile and may be prone to impact loading. This impact loading has been widely known to lead to cracks in the silicon solar cells that over an extended period of time may significantly degrade performance (output power). In our group's previous work, a 3D helicoidally architected fiber-based polymer composite (enabled by an electrospinning-based additive manufacturing methodology) was found to exhibit excellent impact resistance-absorbing much of the energy from the impact load-such that the silicon solar cells encapsulated on both sides by this material breaks only at significantly higher impact load/energy, compared to when a standard, commercial PV encapsulant material was used. In the present study, we aim to use numerical simulation and modeling to enhance our understanding of the stress distribution and evolution during impact loading on such helicoidally arranged fiber-based composite materials, and thus the damage evolution and mechanisms. This could further aid the implementation of the lightweight PV technology for the unique market needs, especially in countries with extreme winter seasons.

20.
Polymers (Basel) ; 14(3)2022 Jan 25.
Article in English | MEDLINE | ID: mdl-35160464

ABSTRACT

Glass-Fiber-Reinforced Polymer (GFRP) laminates are widely used in the automotive and marine industries such as auto bodies and boat hulls. Decreasing the weight and improving the reparability of GFRP parts will cut down material usage, fuel consumption and repair costs. This study shows a bio-inspired helicoidal stacking configuration that significantly improves the impact performance and fiber damage resistance of GFRP laminates. For similar impact performance in terms of perforation energy, the helicoidal GFRP laminate is 20% lighter than the conventional quasi-isotropic GFRP laminate. Upon impact, delaminations and matrix splits link-up and grow extensively throughout the helicoidal laminate. This effectively reduces fiber damage and improves impact performance. Because helicoidal GFRP laminates are resistant to fiber damage and composite healing agents can effectively repair non-fiber damage, embedding healing agents into helicoidal GFRP results in lightweight, inexpensive and healable laminates.

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