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1.
Acta Crystallogr C Struct Chem ; 80(Pt 9): 478-486, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39115535

RESUMEN

It is well known that Hirshfeld surfaces provide an easy and straightforward way of analysing intermolecular interactions in the crystal environment. The use of atomic Hirshfeld surfaces has also demonstrated that such surfaces carry information related to chemical bonds which allow a deeper evaluation of the structures. Here we briefly summarize the approach of atomic Hirshfeld surfaces while further evaluating the kind of information that can be retrieved from them. We show that the analysis of the metal-centre Hirshfeld surfaces from structures refined via Hirshfeld Atom Refinement (HAR) allow accurate evaluation of contacts of type M...H, and that such contacts can be related to the overall shape of the surfaces. The compounds analysed were tetraaquabis(3-carboxypropionato)metal(II), [M(C4H3O4)2(H2O)4], for metal(II)/M = manganese/Mn, cobalt/Co, nickel/Ni and zinc/Zn. We also evaluate the sensitivity of the surfaces by an investigation of seemingly flat surfaces through analysis of the curvature functions in the direction of C-C bonds. The obtained values not only demonstrate variations in curvature but also show a correlation with the hybridization of the C atoms involved in the bond.

2.
Tree Physiol ; 44(7)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38959856

RESUMEN

Vulnerability curves (VCs) have been measured extensively to describe the differences in plant vulnerability to cavitation. Although the roles of hydraulic conductivity (Ks,max) and hydraulic safety (P50, embolism resistance), both of which are parameters of VCs ('sigmoidal' type), in tree demography have been evaluated across different forests, the direct linkages between VCs and tree demography are rarely explored. In this study, we combined measured VCs and plot data of 16 tree species in Panamanian seasonal tropical forests to investigate the connections between VCs and tree mortality, recruitment and growth. We found that the mortality and recruitment rates of evergreen species were most significantly positively correlated with P50. However, the mortality and recruitment rates of deciduous species only exhibited significant positive correlations with parameter a, which describes the steepness of VCs and indicates the sensitivity of conductivity loss with water potential decline, but is often neglected. These differences among evergreen and deciduous species may contribute to the poor performance of existing quantitative relationships (such as the fitting relationships for all 16 species) in capturing tree mortality and recruitment dynamics. Additionally, evergreen species presented a significant positive relationship between relative growth rate (RGR) and Ks,max, while deciduous species did not display such relationship. The RGR of both evergreen and deciduous species also displayed no significant correlations with P50 and a. Further analysis demonstrated that species with steeper VCs tended to have high mortality and recruitment rates, while species with flatter VCs were usually those with low mortality and recruitment rates. Our results highlight the important role of parameter a in tree demography, especially for deciduous species. Given that VC is a key component of plant hydraulic models, integrating measured VC rather than optimizing its parameters will help improve the ability to simulate and predict forest response to water availability.


Asunto(s)
Modelos Biológicos , Tallos de la Planta , Árboles , Árboles/fisiología , Árboles/crecimiento & desarrollo , Tallos de la Planta/fisiología , Tallos de la Planta/crecimiento & desarrollo , Bosques , Agua/fisiología , Agua/metabolismo , Panamá
3.
J Phys Condens Matter ; 36(27)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38565130

RESUMEN

Holey Graphene(HG) is a widely used graphene material for the synthesis of high-purity and highly crystalline materials. The electronic properties of a periodic distribution of lattice holes are explored here, demonstrating the emergence of flat bands. It is established that such flat bands arise as a consequence of an induced sublattice site imbalance, i.e. by having more sites in one of the graphene's bipartite sublattice than in the other. This is equivalent to the breaking of a path-exchange symmetry. By further breaking the inversion symmetry, gaps and a nonzero Berry curvature are induced, leading to topological bands. In particular, the folding of the Dirac cones from the hexagonal Brillouin zone (BZ) to the holey superlattice rectangular BZ of HG, with sizes proportional to an integerntimes the graphene's lattice parameter, leads to a periodicity in the gap formation such thatn≡0(mod 3). A low-energy hamiltonian for the three central bands is also obtained revealing that the system behaves as an effectiveα-T3graphene material. Therefore, a simple protocol is presented here that allows for obtaining flat bands at will. Such bands are known to increase electron-electron correlation effects. Therefore, the present work provides an alternative system that is much easier to build than twisted systems, allowing for the production of flat bands and potentially highly correlated quantum phases.

4.
J Phys Condens Matter ; 36(23)2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38417157

RESUMEN

The recent discovery of copper-substituted lead phosphate apatite, also known as LK-99, has caught much attention owing to certain experimental evidence of room-temperature superconductivity, although this claim is currently under intensive debate. Be it superconducting or not, we show that the normal state of this material has peculiar quantum geometrical properties that may be related to the magnetism and the mechanism for flat band superconductivity. Based on a recently proposed spinless two-band tight-binding model for the Pb-Cu hexagonal lattice subset of the crystalline structure, which qualitatively captures the two flat bands in the band structure, we elaborate the highly anisotropic Berry curvature and quantum metric in the regions of Brillouin zone where one flat band is above and the other below the Fermi surface. In these regions, the Berry curvature has a pattern in the planar momentum that remains unchanged along the out-of-plane momentum. Moreover, the net orbital magnetization contributed from the Berry curvature is zero, signifying that the magnetism in this material should come from other sources. The quantum metric has a similar momentum dependence, and its two planar components are found to be roughly the same but the out-of-plane component vanishes, hinting that the superfluid stiffness of the flat band superconductivity, shall it occur, may be quite anisotropic.

5.
Eur J Prosthodont Restor Dent ; 32(1): 142-152, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-37988621

RESUMEN

INTRODUCTION: The application of occlusal concepts in prosthodontics is still under debate.This study assessed the impact of compensating curves on the comminution of complete denture wearers. METHODS: Seven edentulous subjects, aged 64.6 ± 2.0 years, were rehabilitated with new muco-supported complete dentures and tested in two occlusal plane settings: with and without compensating curves. A randomised triple-blind clinical trial was conducted, considering one-week and one-month as adaptation periods for dentures. After each trial, the subjects were crossed over to their respective groups. One-week was also chosen as the washout period, and after that, the subjects were re-examined. The masticatory performance and swallowing threshold were determined while chewing Optocal test food. The multiple sieve method was used for fractionation and granulometry. RESULTS: During the masticatory performance and swallowing threshold estimates, no differences were found between the median particle sizes obtained with the both occlusal plane conditions (P ⟩ 0.05). However, the swallowing threshold improved after one month, resulting in smaller particle sizes. Moreover, the chewing rates for the both test foods were also increased (P ⟨ 0.05). CONCLUSIONS: These findings suggest that the compensating curves did not have an impact on the masticatory function of subjects wearing complete dentures.


Asunto(s)
Masticación , Boca Edéntula , Humanos , Dentadura Completa , Oclusión Dental
6.
Spine Surg Relat Res ; 7(6): 504-511, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38084225

RESUMEN

Introduction: Football soccer practice involves considerable risks of lesions, making it difficult to strike a balance between adequate preparation and the demand imposed on athletes. A high incidence of postural disorders among adolescents leads to questions about the influence of sports activity on the athletes' posture and sagittal balance. Methods: A cross-sectional study was conducted from panoramic spine radiographs of 110 professional Brazilian football (soccer) players. They were male and aged between 20 and 30 years. Measurements of pelvic incidence, pelvic tilt (PT), sacral slope, sagittal vertical axis (SVA), and lumbar lordosis were obtained by using the SurgimapⓇ software. Measurement values were compared with the Brazilian literature data. Lordosis type was categorized according to the classification of Roussouly et al., and the presence of spondylolysis and spondylolisthesis was analyzed. Results: Findings indicated that (1) among 110 radiographs analyzed, 104 had appropriate measurement quality; (2) values compared with the Brazilian mean demonstrated that PT and SVA were statistically lower in professional players (P=0.013 and P=0.037, respectively); (3) according to Roussouly et al. most participants presented Type 3 lordosis (54.8%), followed by Type 4 (26.9%); (4) eight athletes (7.7%) had spondylolysis, and among them, seven (6.7%) had spondylolisthesis. Conclusions: Significant differences in PT and SVA were found in professional athletes. The most common type of lordosis was the same as that found in the general population (Type 3), and the incidence of spondylolysis and spondylolisthesis was higher than that found in the general population, but lower than that found in football (soccer) players.

7.
Nanotechnology ; 35(6)2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38009501

RESUMEN

In this work, we present a theoretical model for domain wall (DW) oscillations in a curved magnetic nanowire with a constant curvature under the action of a uniaxial magnetic field. Our results show that the DW dynamics can be described as that of the mechanical pendulum, and both the NW curvature and the external magnetic field influence its oscillatory frequency. A comparison between our theoretical approach and experimental data in the literature shows an excellent agreement. The results presented here can be used to design devices demanding the proper control of the DW oscillatory motion in NWs.

8.
Membranes (Basel) ; 13(9)2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37755218

RESUMEN

The mechanical effects of membrane compositional inhomogeneities are analyzed in a process analogous to neck formation in cellular membranes. We cast on the Canham-Helfrich model of fluid membranes with both the spontaneous curvature and the surface tension being non-homogeneous functions along the cell membrane. The inhomogeneous distribution of necking forces is determined by the equilibrium mechanical equations and the boundary conditions as considered in the axisymmetric setting compatible with the necking process. To establish the role played by mechanical inhomogeneity, we focus on the catenoid, a surface of zero mean curvature. Analytic solutions are shown to exist for the spontaneous curvature and the constrictive forces in terms of the border radii. Our theoretical analysis shows that the inhomogeneous distribution of spontaneous curvature in a mosaic-like neck constrictional forces potentially contributes to the membrane scission under minimized work in living cells.

9.
J Membr Biol ; 256(4-6): 317-330, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37097306

RESUMEN

Using a flexibility prediction algorithm and in silico structural modeling, we have calculated the intrinsic flexibility of several magainin derivatives. In the case of magainin-2 (Mag-2) and magainin H2 (MAG-H2) we have found that MAG-2 is more flexible than its hydrophobic analog, Mag-H2. This affects the degree of bending of both peptides, with a kink around two central residues (R10, R11), whereas, in Mag-H2, W10 stiffens the peptide. Moreover, this increases the hydrophobic moment of Mag-H2, which could explain its propensity to form pores in POPC model membranes, which exhibit near-to-zero spontaneous curvatures. Likewise, the protective effect described in DOPC membranes for this peptide regarding its facilitation in pore formation would be related to the propensity of this lipid to form membranes with negative spontaneous curvature. The flexibility of another magainin analog (MSI-78) is even greater than that of Mag-2. This facilitates the peptide to present a kind of hinge around the central F12 as well as a C-terminal end prone to be disordered. Such characteristics are key to understanding the broad-spectrum antimicrobial actions exhibited by this peptide. These data reinforce the hypothesis on the determinant role of spontaneous membrane curvature, intrinsic peptide flexibility, and specific hydrophobic moment in assessing the bioactivity of membrane-active antimicrobial peptides.


Asunto(s)
Membrana Dobles de Lípidos , Proteínas de Xenopus , Magaininas/química , Proteínas de Xenopus/análisis , Proteínas de Xenopus/química , Membranas/química , Membrana Dobles de Lípidos/química
10.
J Phys Condens Matter ; 35(15)2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36753769

RESUMEN

In two-dimensional time-reversal symmetric topological insulators described by Dirac models, theZ2topological invariant can be described by the spin Chern number. We present a linear response theory for the spin Berry curvature that integrates to the spin Chern number, and introduce its spectral function that can be measured at finite temperature by momentum- and spin-resolved circular dichroism, which may be achieved by pump-probe type of experiments using spin- and time-resolved ARPES. As a result, the sign of the Pfaffian of theZ2invariant can be directly measured. A spin Chern number spectral function is further introduced from the optical spin current response, and is shown to be measurable from the spin-resolved opacity of two-dimensional materials under circularly polarized light, pointing to an optical measurement of theZ2invariant and a frequency sum rule. The spin Chern number expressed in real space is known to yield a spin Chern marker, and we propose that it may be measurable from spin-resolved local heating rate caused by circularly polarized light. A nonlocal spin Chern marker is further proposed to characterize the quantum criticality near topological phase transitions, and is shown to be equivalent to an overlap between spin-selected Wannier states.

11.
Membranes (Basel) ; 13(2)2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36837693

RESUMEN

In this revision work, we emphasize the close relationship between the action of phospholipases and the modulation of membrane curvature and curvature stress resulting from this activity. The alteration of the tridimensional structure of membranes upon the action of phospholipases is analyzed based on studies on model lipid membranes. The transient unbalance of both compositional and physical membrane properties between the hemilayers upon phospholipase activity lead to curvature tension and the catalysis of several membrane-related processes. Several proteins' membrane-bound and soluble forms are susceptible to regulation by the curvature stress induced by phospholipase action, which has important consequences in cell signaling. Additionally, the modulation of membrane fusion by phospholipase products regulates membrane dynamics in several cellular scenarios. We commented on vesicle fusion in the Golgi-endoplasmic system, synaptic vesicle fusion to the plasma membrane, viral membrane fusion to host cell plasma membrane and gametes membrane fusion upon acrosomal reaction. Furthermore, we explored the modulation of membrane fusion by the asymmetric adsorption of amphiphilic drugs. A deep understanding of the relevance of lipid membrane structure, particularly membrane curvature and curvature stress, on different cellular events leads to the challenge of its regulation, which may become a powerful tool for pharmacological therapy.

12.
Semina ciênc. agrar ; 44(1): 171-184, jan.-fev. 2023. tab, graf
Artículo en Inglés | VETINDEX | ID: biblio-1418816

RESUMEN

The objective of this work was to compare three methods for estimating the optimal plot size to evaluate the fresh matter productivity of white oat (Avena sativa L.), IPR Suprema cultivar. Six uniformity trials (blank experiments) were carried out, three trials on the first sowing date (May 3, 2021) and three trials on the second sowing date (May 26, 2021). Fresh matter productivity was evaluated in 216 basic experimental units (BEU) of 1 m × 1 m (36 BEU per trial). The BEU was formed by five rows of 1.0 m in length, spaced 0.20 m apart, totaling 1.0 m2. The optimal plot size was determined using the methods of modified maximum curvature, linear response and plateau model and quadratic response and plateau model. The optimal plot size differs between the methods and decreases in the following order: quadratic response and plateau model (11.09 m2), linear response and plateau model (7.65 m2) and modified maximum curvature (4.00 m2). The optimal plot size to evaluate the fresh matter productivity of white oat is 7.65 m2 and the experimental precision stabilizes from this size on.


O objetivo deste trabalho foi comparar três métodos de estimação do tamanho ótimo de parcela para avaliar a produtividade de matéria fresca de aveia branca (Avena sativa L.), cultivar IPR Suprema. Foram conduzidos seis ensaios de uniformidade (experimentos em branco), sendo três na primeira data de semeadura (03 de maio de 2021) e três na segunda data de semeadura (26 de maio de 2021). Foi avaliada a produtividade de matéria fresca em 216 unidades experimentais básicas (UEB) de 1 m × 1 m (36 UEB por ensaio). A UEB foi formada por cinco fileiras de 1,0 m de comprimento, espaçadas 0,20 m entre fileiras, totalizando 1,0 m2. Foi determinado o tamanho ótimo de parcela por meio dos métodos da curvatura máxima modificado, do modelo linear de resposta com platô e do modelo quadrático de resposta com platô. O tamanho ótimo de parcela difere entre os métodos e decresce na seguinte ordem: modelo quadrático de resposta com platô (11,09 m2), modelo linear de resposta com platô (7,65 m2) e curvatura máxima modificado (4,00 m2). O tamanho ótimo de parcela para avaliar a produtividade de matéria fresca de aveia branca é 7,65 m2 e a precisão experimental estabiliza a partir desse tamanho.


Asunto(s)
Modelos Lineales , Avena/crecimiento & desarrollo
13.
Front Reprod Health ; 4: 863844, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36303674

RESUMEN

Introduction: Peyronie's disease is the disease that results in an alteration in the curvature of the penis, which can lead to a shortening of length, pain in erection, or difficulties in penetration, thus leading the patient to psychological alterations due to loss of functionality such as aesthetic alteration. That is why there are several studies to define the best form of treatment, which currently continues to be the first choice surgical treatment. Objective: We present the most recommended therapies for Peyronie's disease and suggest an algorithm as a guide to direct therapy. Methods: We used the PubMed platform to review the literature related to Peyronie's disease. Various editorials were reviewed as well as original articles and reviews focusing on the various treatments as well as their indications and results. Results: Peyronie's disease in which conservative or drug treatment does not have a response, surgical treatment with corporoplasty, penile prosthesis implantation or both may be indicated. Corporoplasty refers to both the plication of the tunica albuginea as well as the incision of the tunica with the placement of a graft. An accurate history should always be carried out to identify erectile dysfunction as well as to be able to guide you on the repercussions of the treatment. If refractory erectile dysfunction is present, placement of a penile prosthesis with or without further adjunctive straightening maneuvers is recommended. We reviewed the indications, advantages, disadvantages, and results of the available techniques, and proposed a surgical treatment algorithm. Conclusion: Penile shortening procedures are usually indicated in curvatures <60°, in penises with adequate length. Partial excision/incision and grafting are indicated for curvatures >60°, hourglass or hinge deformities, and short penises, if the patient's erectile function is adequate. The presence of "borderline" erectile function and/or ventral curvature tilts the choice toward shortening procedures, and refractory erectile dysfunction is an indication for penile prosthesis placement. An accurate risk/benefit assessment of the individual patient as well as meticulous patient counseling are critically important.

14.
Entropy (Basel) ; 24(9)2022 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-36141083

RESUMEN

In this work, we introduce an extension of the study of the first law of thermodynamics of black holes based on the geometry of the extended phase space for AdS Lovelock gravities, which includes changes in scales. As expected, the result obtained coincides with the previously known four-dimensional case. For higher dimensions, the result is the rise of two new contributions to the first law of thermodynamics. The first term corresponds to corrections of the usual definition of thermodynamic volumes at the horizon due to the presence of the higher curvature terms. The second term arises in odd dimensions, comes from the asymptotic region, and corresponds to a scale transformation of the form ∝δ^ln(l/ℓ), with l the AdS radius and ℓ a parameter. A particularly interesting case corresponds to the Chern Simons gravity where the change scale does not generate a contribution at the asymptotic region, likely due to the Chern Simons AdS local symmetry.

15.
Polymers (Basel) ; 14(4)2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35215653

RESUMEN

Protein adsorption onto nanomaterials is a process of vital significance and it is commonly controlled by functionalizing their surface with polymers. The efficiency of this strategy depends on the design parameters of the nanoconstruct. Although significant amount of work has been carried out on planar surfaces modified with different types of polymers, studies investigating the role of surface curvature are not as abundant. Here, we present a comprehensive and systematic study of the protein adsorption process, analyzing the effect of curvature and morphology, the grafting of polymer mixtures, the type of monomer (neutral, acidic, basic), the proteins in solution, and the conditions of the solution. The theoretical approach we employed is based on a molecular theory that allows to explicitly consider the acid-base reactions of the amino acids in the proteins and the monomers on the surface. The calculations showed that surface curvature modulates the molecular organization in space, but key variables are the bulk pH and salt concentration (in the millimolar range). When grafting the NP with acidic or basic polymers, the surface coating could disfavor or promote adsorption, depending on the solution's conditions. When NPs are in contact with protein mixtures in solution, a nontrivial competitive adsorption process is observed. The calculations reflect the balance between molecular organization and chemical state of polymers and proteins, and how it is modulated by the curvature of the underlying surface.

16.
Int Endod J ; 55(1): 124-136, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34687053

RESUMEN

AIM: To evaluate the shaping ability of several heat-treated nickel-titanium systems used to prepare root canals with moderate and severe curvature, in extracted mandibular molars, by micro-computed tomography, considering their variation in kinematics and design. METHODOLOGY: Curved-mesial roots of mandibular molars were randomly selected and assigned into 4 balanced experimental groups (n = 10), established by determining homogeneous 3D parameters of volume and surface area: R-Motion (RM) size 30, 0.04 taper (RM; FKG Dentaire), Reciproc Blue (RCB) size 25, 0.08 taper (RCB; VDW GmbH), HyFlex CM (HFX) size 30, 0.04 taper (HFX; Coltène Whaledent) and XP-endo Shaper size (XPS) 30, 0.01 taper (XPS; FKG Dentaire). The volume of irrigation was established at 10 ml of 2.5% NaOCl. Throughout the entire root canal preparation procedures, the samples were fixed in a vice submerged in a container with water monitored at 37°C. Dimensional cross-sectional measures of area, perimeter, roundness, major/minor diameters and 3-dimensional (volume, surface area, structure model index - SMI) parameters as well as the smallest dentine thickness along the cervical and middle root thirds were evaluated by micro-CT. Data were analysed using analysis of variance and post hoc Tukey tests (α = 5%). RESULTS: Reciproc Blue and XPS had significantly greater mean increases in cross-sectional area measurements, only in the middle third, when compared with RM and HFX (p < .05). RM, RCB and XPS had a similar increase in measurements of length and width of perimeter (p > .05), and HFX had significantly lower mean increases in perimeter values only when compared with XPS (p < .05). RCB and XPS had significantly greater mean increases in volume when compared with RM and HFX (p < .05). RM had a significantly lower difference in SMI after preparation, compared with RCB, HFX and XPS (p < .05). The smallest dentine thickness was observed after the use of RCB (p < .05), in the danger and safety zones. CONCLUSIONS: XP-endo Shaper and RM had a shaping ability similar to that of instruments with larger tapers, achieved with less dentine removal in danger and safe zones in curved-mesial canals of extracted molar teeth treated on a laboratory benchtop.


Asunto(s)
Cavidad Pulpar , Preparación del Conducto Radicular , Cavidad Pulpar/diagnóstico por imagen , Diseño de Equipo , Diente Molar/diagnóstico por imagen , Diente Molar/cirugía , Níquel , Titanio , Microtomografía por Rayos X
17.
Ciênc. rural (Online) ; 52(12): e20210747, 2022. tab, graf
Artículo en Inglés | VETINDEX | ID: biblio-1375161

RESUMEN

This study compared four methods for defining the ideal sample size per experimental unit to estimate the overall experimental mean for the total length, shoot length, root length, and the number of leaves of cauliflower seedlings. An experiment was carried out where the number of leaves, shoot, root, and total length were measured, and the general, perpendicular distance, linear response plateau, and spline methods were tested. While the general method may under or overestimate sample size and the sampling of 10 seedlings suggested by the spline method is still too far from the stabilization point of the curve, the perpendicular distance and linear plateau response methods are recommended to obtain results corresponding to narrower confidence interval widths. Therefore, according to the perpendicular distance method, at least 15 seedlings per experimental unit are required to estimate the overall experimental mean of cauliflower seedlings reliably for the traits here measured.


Este estudo comparou quatro métodos para definir o tamanho amostral ideal por unidade experimental para estimar a média experimental geral para o comprimento total, comprimento de parte aérea, comprimento de raiz e número de folhas de mudas de couve-flor. Um experimento foi conduzido no qual foram medidos o número de folhas, o comprimento total, de parte aérea e de radícula, e foram testados os métodos: geral, de distâncias perpendiculares, resposta linear platô e spline. Enquanto o método geral pode sub ou superestimar o tamanho amostral e a amostragem de 10 mudas sugerida pelo método spline ainda se encontra muito distante do ponto de estabilização da curva, os métodos de distâncias perpendiculares e resposta linear platô são recomendados por obterem resultados que corresponderam a amplitudes de intervalos de confiança menores. Portanto, de acordo com o método de distâncias perpendiculares, pelo menos 15 mudas por unidade experimental são necessárias para estimar a média experimental geral de mudas de couve-flor confiavelmente para as variáveis aqui mensuradas.


Asunto(s)
Brassica/anatomía & histología , Brotes de la Planta/anatomía & histología , Estándares de Referencia , 24444
18.
Obes Surg ; 31(7): 3382-3383, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33783680

RESUMEN

PURPOSE: Laparoscopic gastric plication (LGP) is a relative new bariatric procedure with a high revision rate, mostly to sleeve gastrectomy. There are few reported cases of conversion to Roux-en-Y gastric bypass (RYGB). The purpose of this video was to show the feasibility and safety, as well as the main technical aspects, of a laparoscopic conversion of gastric plication to RYGB. MATERIALS AND METHODS: A 40-year-old morbidly obese woman with a previous LGP, consulted for insufficient weight loss, weight regain, and gastroesophageal reflux disease (GERD) symptoms, and was converted to RYGB. RESULTS: Surgical technique included lysis of adhesions between the stomach and the greater omentum, take down of the plication, partial gastrectomy of the devascularized fundus and body and conversion to RYGB. At 30 months, she has achieved a total weight loss (TWL) of 42.43% with no GERD symptoms recurrence. CONCLUSION: Conversion to RYGB is a safe and effective option to treat weight recidivism and GERD after LGP.


Asunto(s)
Derivación Gástrica , Laparoscopía , Obesidad Mórbida , Adulto , Femenino , Gastrectomía , Humanos , Obesidad Mórbida/cirugía , Reoperación , Estudios Retrospectivos , Estómago
19.
Fisioter. Mov. (Online) ; 34: e34117, 2021. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1339909

RESUMEN

Abstract Introduction: There are no studies that investigate whether different workout endings of the Pilates method (PM), either prioritizing the activation of powerhouse muscles or the relaxation of muscles trained during the session, affects spinal curvature. Objective: Identify the immediate effect of a PM session that ends with soft tissue mobilization or wall exercises on the kyphotic and lumbar lordotic angles. Methods: A crossover clinical trial with 19 female Pilates practitioners that used a Flexicurve ruler to evaluate thoracic and lumbar spine curvature before and after a PM exercise protocol, and after endings that involved soft tissue mobilization using massage balls or wall exercises. The order of the different endings was chosen by random draw and the study volunteers participated in two interventions, with intervals of seven to ten days between them. Two two-way ANOVAs were performed (one for each postural variable), using the factors "assessment time" (pre-session; post-PE; post-ending) and "type of ending" (soft tissue or wall exercises). Results: There was no significant difference between the assessment times or endings for the kyphotic (p = 0.972; p = 0.747) and lumbar lordotic angles (p = 0.574; p = 0.627), respectively. Conclusion: Pilates instructors can opt for more relaxing or more active endings without affecting the kyphotic and lumbar lordotic angles.


Resumo Introdução: Ainda não há pesquisas que demonstrem se diferentes maneiras de finalização da sessão no método Pilates (MP), priorizando a ativação da musculatura do power house ou o relaxamento da musculatura trabalhada durante a sessão têm efeito sobre os ângulos de curvatura da coluna. Objetivo: Identificar qual é o efeito imediato de uma sessão do MP finalizada com mobilização de tecidos moles ou com exercícios na parede sobre os ângulos das curvaturas da coluna torácica e lombar. Métodos: Trata-se de um ensaio clínico cruzado, composto por 19 mulheres praticantes de Pilates, que avaliou as curvaturas torácica e lombar através do flexicurva antes e após um protocolo de exercícios do MP, e depois as finalizações de mobilização de tecidos moles através de bolas de massagem e de exercícios na parede. A escolha da ordem das diferentes finalizações foi realizada por sorteio e as voluntárias da pesquisa participaram das duas intervenções com intervalos entre sete e dez dias. Para análise, foram realizadas duas ANOVAs two-way (uma para cada variável postural) com os fatores "momento avaliativo" (pré-sessão; pós-PE; pós-finalização) e "tipo de finalização" (tecidos moles e parede). Resultados: Não houve diferença significativa entre os momentos avaliativos e entre o tipo de finalização para os ângulos da cifose dorsal (p = 0,972; p = 0,747) e da lordose lombar (p = 0,574; p = 0,627), respectivamente. Conclusão: Os profissionais podem propor diferentes formas de finalização, optando por uma finalização mais relaxante ou mais ativa, sem que isso interfira no ângulo das curvaturas torácica e lombar da coluna vertebral.

20.
Sensors (Basel) ; 20(13)2020 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-32635602

RESUMEN

In this paper, we propose and experimentally demonstrate a simple technique to enhance the curvature sensitivity of a bending fiber optic sensor based on anti-resonant reflecting optical waveguide (ARROW) guidance. The sensing structure is assembled by splicing a segment of capillary hollow-core fiber (CHCF) between two single-mode fibers (SMF), and the device is set on a steel sheet for measuring different curvatures. Without any surface treatment, the ARROW sensor exhibits a curvature sensitivity of 1.6 dB/m-1 in a curvature range from 0 to 2.14 m-1. By carefully coating half of the CHCF length with polydimethylsiloxane (PDMS), the curvature sensitivity of the ARROW sensor is enhanced to -5.62 dB/m-1, as well as an increment in the curvature range (from 0 to 2.68 m-1). Moreover, the covered device exhibits a low-temperature sensitivity (0.038 dB/°C), meaning that temperature fluctuations do not compromise the bending fiber optic sensor operation. The ARROW sensor fabricated with this technique has high sensitivity and a wide range for curvature measurements, with the advantage that the technique is cost-effective and easy to implement. All these features make this technique appealing for real sensing applications, such as structural health monitoring.

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