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1.
FEMS Microbiol Lett ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39271451

RESUMEN

In recent years, the emergence of multidrug-resistant bacteria has limited the selection of drugs for treating bacterial infections, reduced clinical efficacy, and increased treatment costs and mortality. It is urgent to find alternative antibiotics. In order to explore a new method for controlling methicillin resistant Staphylococcus aureus (S. aureus) , this study isolated and purified a multi drug resistant S. aureus broad-spectrum phage JPL-50 from wastewater. JPL-50 belongs to the Siphoviridae family after morphological observation, biological characterization, and transmission electron microscopy (TEM) fragmentation spectrum analysis. It can cleave 84% of tested S. aureus (168/200) , in which 100% of tested mastitis-associated strains (48/48) and 72.04% of MRSA strains (67/93) were lysed. In addition, it has an optimal growth temperature of about 30°C, a high activity within a wide pH range (pH 3-10) , and an optimal multiplicity of infection of 0.01. The one-step growth curve shows a latent time of 20 minutes, an explosive time of 80 minutes. JPL-50 was 16, 927 bp in length and was encoded by double-stranded DNA, with no genes associated with bacterial resistance or virulence factors detected. In a therapeutic study, injection of the phage JPL-50 once and for 7 times in 7 days protected 40% and 60% of the mice from fatal S.aureus infection, respectively. More importantly, JPL-50-doxycycline combination could effectively inhibit host S.aureus in vitro and reduce the use of doxycycline within 8 hours. In conclusion, the bacteriophage JPL-50 has a wide lysis spectrum, high lysis rate, high tolerance to extreme environments, and moderate in vivo activity, providing ideas for developing multidrug-resistant S. aureus infections.

2.
IUCrJ ; 11(Pt 5): 695-707, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39190506

RESUMEN

The TIR (Toll/interleukin-1 receptor) domain represents a vital structural element shared by proteins with roles in immunity signalling pathways across phyla (from humans and plants to bacteria). Decades of research have finally led to identifying the key features of the molecular basis of signalling by these domains, including the formation of open-ended (filamentous) assemblies (responsible for the signalling by cooperative assembly formation mechanism, SCAF) and enzymatic activities involving the cleavage of nucleotides. We present a historical perspective of the research that led to this understanding, highlighting the roles that different structural methods played in this process: X-ray crystallography (including serial crystallography), microED (micro-crystal electron diffraction), NMR (nuclear magnetic resonance) spectroscopy and cryo-EM (cryogenic electron microscopy) involving helical reconstruction and single-particle analysis. This perspective emphasizes the complementarity of different structural approaches.


Asunto(s)
Complejos Multiproteicos , Receptores Inmunológicos , Transducción de Señal , Humanos , Microscopía por Crioelectrón , Cristalografía por Rayos X , Inmunidad Innata , Espectroscopía de Resonancia Magnética/métodos , Dominios Proteicos , Receptores Inmunológicos/química , Receptores Inmunológicos/metabolismo , Receptores de Interleucina-1/química , Receptores de Interleucina-1/metabolismo , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo
3.
Small ; : e2405865, 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39180457

RESUMEN

The introduction of noble metal into spinel structure is an effective strategy to develop efficient oxygen evolution/reduction reaction (OER/ORR) catalysts. Herein, surface Cooct is substituted by Ruoct in Rux-Mn0.5Co2.5-xO4/NCNTs by ion-exchange, where presence of Ruoct─O─Cooct unit facilitates electron transfer. This strong electron coupling effect leads downward shift in d-band center and a narrowing of d-p bandgap. The increased charge density of Cooct bridged with Ruoct dioxygen optimizes adsorption of oxygen intermediates (*OH) and occupation of electrons in eg-orbital octahedral. The measured ORR/OER voltage difference is only 0.71 V. The peak power density of assembled zinc-air battery reaches 148.8 mW h cm-2, and energy density at 100 mA cm-2 reaches 813.6 mA h gZn -1, approaching a theoretical value of 820 mA h gZn -1. The catalyst demonstrates stable operation for over 500 h at 10 mA cm-2 and over 200 h at 50 mA cm-2. This work provides new insights to guide fabrication of advanced oxygen electrocatalysts.

4.
Angew Chem Int Ed Engl ; : e202413866, 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39175142

RESUMEN

Prussian blue analogues (PBA) are a large family of functional materials with diverse applications such as in electrochemical fields. However, their use in the emerging two-electron oxygen reduction reaction for clean production of hydrogen peroxide (H2O2) is lagging. Herein, a general solvent exchange induced reconstruction strategy is demonstrated, through which an abnormal NiNi-PBA superstructure is synthesized as a high-performance electrocatalyst for H2O2 generation. The resultant NiNi-PBA superstructure has a stoichiometric composition with saturated lattice water, and a leaf-like morphology composed of interconnected small-size nanosheets with identical orientation and predominate {210} side surface exposure. Our studies show that the Ni-N centers on {210} facets are the active sites, and the saturated lattice H2O favors a six-coordinated environment that results in high selectivity. The "perfect" structure including stoichiometric composition and ideal facet exposure leads to a high selectivity of ~100% and H2O2 yield of 5.7 mol g-1 h-1, superior to the reported MOF-based electrocatalysts and most other electrocatalysts.

5.
Front Endocrinol (Lausanne) ; 15: 1414213, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39006360

RESUMEN

Objective: To explore the impact of the level of differentiation in a minimum of two follicles with a diameter of ≥18 mm on the outcome of controlled ovarian hyperstimulation on the day of human chorionic gonadotropin (hCG) administration. Methods: Single-center data from January 2018 to December 2021 was retrospectively analyzed for 1,199 patients with fresh embryo transfer for assisted reproduction. The absolute value of the standard deviation of the follicle size of at least 2 follicles ≥18 mm in diameter in both ovaries on the day of hCG was taken as the degree of differentiation of the dominant follicle after ovulation induction, based on the standard deviation response to the degree of dispersion of the data. The degree of follicular differentiation was divided into 3 groups according to the size of the value, and the general clinical conditions, laboratory indexes, and clinical outcomes of the patients in the 3 groups were compared. Results: Among the three groups, the body mass index (BMI) of the ≤1s group was lower than that of the other two groups (P< 0.05), while the follicle-stimulating hormone (FSH) and Anti-Mullerian hormone (AMH) were higher (P< 0.05), and the implantation rate and clinical pregnancy rate were significantly higher than those of the other two groups (P< 0.01). After multifactorial logistic regression to correct for confounding factors, with the ≤1s group as the reference, the implantation rate, hCG-positive rate, clinical pregnancy rate and live birth rate of embryo transfer in the ≥2S group were significantly lower (P< 0.01). The results of curve fitting analysis showed that the live birth rate decreased gradually with the increase of the absolute standard deviation (P=0.0079). Conclusion: Differences in follicle diameters ≥18 mm on the day of hCG injection did not have an impact on embryo quality, but had an impact on pregnancy outcomes. The less the variation in follicle size, the more homogeneous the follicle development and the higher the likelihood of live births.


Asunto(s)
Gonadotropina Coriónica , Transferencia de Embrión , Folículo Ovárico , Inducción de la Ovulación , Índice de Embarazo , Humanos , Femenino , Inducción de la Ovulación/métodos , Folículo Ovárico/efectos de los fármacos , Folículo Ovárico/crecimiento & desarrollo , Gonadotropina Coriónica/administración & dosificación , Adulto , Embarazo , Estudios Retrospectivos , Transferencia de Embrión/métodos , Fertilización In Vitro/métodos
6.
Small Methods ; 8(7): e2301229, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38528393

RESUMEN

The charge-transfer (CT) interactions between organic compounds are reflected in the (opto)electronic properties. Determining and visualizing crystal structures of CT complexes are essential for the design of functional materials with desirable properties. Complexes of pyranine (PYR), methyl viologen (MV), and their derivatives are the most studied water-based CT complexes. Nevertheless, very few crystal structures of CT complexes have been reported so far. In this study, the structures of two PYRs-MVs CT crystals and a map of the noncovalent interactions using 3D electron diffraction (3DED) are reported. Physical properties, e.g., band structure, conductivity, and electronic spectra of the CT complexes and their crystals are investigated and compared with a range of methods, including solid and liquid state spectroscopies and highly accurate quantum chemical calculations based on density functional theory (DFT). The combination of 3DED, spectroscopy, and DFT calculation can provide important insight into the structure-property relationship of crystalline CT materials, especially for submicrometer-sized crystals.

7.
Angew Chem Int Ed Engl ; 63(16): e202317695, 2024 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-38380831

RESUMEN

3D electron diffraction (3D ED) has shown great potential in crystal structure determination in materials, small organic molecules, and macromolecules. In this work, an automated, low-dose and low-bias 3D ED protocol has been implemented to identify six phases from a multiple-phase melt-crystallisation product of an active pharmaceutical ingredient, griseofulvin (GSF). Batch data collection under low-dose conditions using a widely available commercial software was combined with automated data analysis to collect and process over 230 datasets in three days. Accurate unit cell parameters obtained from 3D ED data allowed direct phase identification of GSF Forms III, I and the known GSF inclusion complex (IC) with polyethylene glycol (PEG) (GSF-PEG IC-I), as well as three minor phases, namely GSF Forms II, V and an elusive new phase, GSF-PEG IC-II. Their structures were then directly determined by 3D ED. Furthermore, we reveal how the stabilities of the two GSF-PEG IC polymorphs are closely related to their crystal structures. These results demonstrate the power of automated 3D ED for accurate phase identification and direct structure determination of complex, beam-sensitive crystallisation products, which is significant for drug development where solid form screening is crucial for the overall efficacy of the drug product.


Asunto(s)
Electrones , Polímeros , Polímeros/química , Griseofulvina/química , Polietilenglicoles/química , Cristalización/métodos
8.
Micromachines (Basel) ; 14(12)2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38138381

RESUMEN

We propose a novel silicon carbide (SiC) self-aligned N-type ion implanted trench MOSFET (NITMOS) device. The maximum electric field in the gate oxide could be effectively reduced to below 3 MV/cm with the introduction of the P-epi layer below the trench. The P-epi layer is partially counter-doped by a self-aligned N-type ion implantation process, resulting in a relatively low specific on-resistance (Ron,sp). The lateral spacing between the trench sidewall and N-implanted region (Wsp) plays a crucial role in determining the performance of the SiC NITMOS device, which is comprehensively studied through the numerical simulation. With the Wsp increasing, the SiC NITMOS device demonstrates a better short-circuit capability owing to the reduced saturation current. The gate-to-drain capacitance (Cgd) and gate-to-drain charge (Qgd) are also investigated. It is observed that both Cgd and Qgd decrease as the Wsp increases, owing to the enhanced screen effect. Compared to the SiC double-trench MOSFET device, the optimal SiC NITMOS device exhibits a 79% reduction in Cgd, a 38% decrease in Qgd, and a 41% reduction in Qgd × Ron,sp. A higher switching speed and a lower switching loss can be achieved using the proposed structure.

9.
Angew Chem Int Ed Engl ; 62(39): e202309614, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37552235

RESUMEN

Conducting polymers with high theoretical capacitance and deformability are among the optimal candidates for compressible supercapacitor electrode materials. However, achieving both mechanical and electrochemical stabilities in a single electrode remains a great challenge. To address this issue, the "Polymer Chainmail" is proposed with reversible deformation capability and enhances stability because of the steric hindrance and charge compensation effect of doped anions. As a proof of concept, four common anions are selected as dopants for Poly(3,4-ethylenedioxythiophene) (PEDOT), and their effects on the adsorption and diffusion of H+ on PEDOT are verified using density functional theory calculations. Owing to the film formation effect, the PF 6 - ${{\rm{PF}}_6^- }$ doped PEDOT/nitrogen-doped carbon foam exhibits good mechanical properties. Furthermore, the composite demonstrates excellent rate performance and stability due to suitable anion doping. This finding provides new insights into the preparation of electrochemically stable conductive polymer-based compressible electrode materials.

10.
Artículo en Inglés | MEDLINE | ID: mdl-37478036

RESUMEN

Recent neural rendering methods have made great progress in generating photorealistic human avatars. However, these methods are generally conditioned only on low-dimensional driving signals (e.g., body poses), which are insufficient to encode the complete appearance of a clothed human. Hence they fail to generate faithful details. To address this problem, we exploit driving view images (e.g., in telepresence systems) as additional inputs. We propose a novel neural rendering pipeline, Hybrid Volumetric-Textural Rendering (HVTR++), which synthesizes 3D human avatars from arbitrary driving poses and views while staying faithful to appearance details efficiently and at high quality. First, we learn to encode the driving signals of pose and view image on a dense UV manifold of the human body surface and extract UV-aligned features, preserving the structure of a skeleton-based parametric model. To handle complicated motions (e.g., self-occlusions), we then leverage the UV-aligned features to construct a 3D volumetric representation based on a dynamic neural radiance field. While this allows us to represent 3D geometry with changing topology, volumetric rendering is computationally heavy. Hence we employ only a rough volumetric representation using a pose- and image-conditioned downsampled neural radiance field (PID-NeRF), which we can render efficiently at low resolutions. In addition, we learn 2D textural features that are fused with rendered volumetric features in image space. The key advantage of our approach is that we can then convert the fused features into a high-resolution, high-quality avatar by a fast GAN-based textural renderer. We demonstrate that hybrid rendering enables HVTR++ to handle complicated motions, render high-quality avatars under user-controlled poses/shapes, and most importantly, be efficient at inference time. Our experimental results also demonstrate state-of-the-art quantitative results.

11.
Nat Chem ; 15(6): 848-855, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37081207

RESUMEN

Continuous-rotation 3D electron diffraction methods are increasingly popular for the structure analysis of very small organic molecular crystals and crystalline inorganic materials. Dynamical diffraction effects cause non-linear deviations from kinematical intensities that present issues in structure analysis. Here, a method for structure analysis of continuous-rotation 3D electron diffraction data is presented that takes multiple scattering effects into account. Dynamical and kinematical refinements of 12 compounds-ranging from small organic compounds to metal-organic frameworks to inorganic materials-are compared, for which the new approach yields significantly improved models in terms of accuracy and reliability with up to fourfold reduction of the noise level in difference Fourier maps. The intrinsic sensitivity of dynamical diffraction to the absolute structure is also used to assign the handedness of 58 crystals of 9 different chiral compounds, showing that 3D electron diffraction is a reliable tool for the routine determination of absolute structures.

12.
Int J Gynaecol Obstet ; 162(3): 913-921, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37010882

RESUMEN

OBJECTIVES: To explore the effect of abnormally elevated serum alanine aminotransferase (ALT) on pregnancy outcomes in patients with moderate and severe ovarian hyperstimulation syndrome (OHSS) at disease onset. METHODS: This was a single-center retrospective cohort study conducted between January 1, 2014 and October 31, 2021. A total of 3550 fresh in vitro fertilization/intracytoplasmic sperm injection embryo transfer cycles were included, using Golan's three-degree, five-level classification to diagnose patients with OHSS. According to the patient's ALT level after diagnosis of OHSS, 123 (3.46%) patients with moderate-to-severe OHSS were divided into two groups. A control group included 3427 (96.54%) non-OHSS patients, and 91 (2.56%) abnormal ALT patients were matched with the control group for propensity scores. RESULTS: There was no difference in baseline data between the abnormal ALT and matched control groups. The incidence of obstetric complications was significantly higher in the abnormal ALT group than in the matched control group (P < 0.05). After adjusting for confounding factors, the incidence of obstetric complications in the abnormal ALT group was still higher than that in the normal ALT group (P < 0.05). CONCLUSION: In patients with moderate and severe OHSS, higher ALT levels resulted in an increased risk of obstetric and neonatal complications.


Asunto(s)
Alanina Transaminasa , Síndrome de Hiperestimulación Ovárica , Femenino , Humanos , Recién Nacido , Embarazo , Alanina Transaminasa/sangre , Fertilización In Vitro/métodos , Síndrome de Hiperestimulación Ovárica/epidemiología , Inducción de la Ovulación/efectos adversos , Índice de Embarazo , Estudios Retrospectivos
13.
BMC Health Serv Res ; 23(1): 99, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36717832

RESUMEN

BACKGROUND: Noncommunicable diseases (NCDs) and mental health conditions represent a growing proportion of disease burden in low- and middle-income countries (LMICs). While past efforts have identified interventions to be delivered across health system levels to address this burden, the challenge remains of how to deliver heterogenous interventions in resource-constrained settings. One possible solution is the Integration of interventions within existing care delivery models. This study reviews and summarizes published literature on models of integrated NCD and mental health care in LMICs. METHODS: We searched Pubmed, African Index Medicus and reference lists to conduct a scoping review of studies describing an integrated model of NCD or neuropsychiatric conditions (NPs) implemented in a LMIC. Conditions of interest were grouped into common and severe NCDs and NPs. We identified domains of interest and types of service integration, conducting a narrative synthesis of study types. Studies were screened and characteristics were extracted for all relevant studies. Results are reported using PRISMA-ScR. RESULTS: Our search yielded 5004 studies, we included 219 models of integration from 188 studies. Most studies were conducted in middle-income countries, with the majority in sub-Saharan Africa. Health services were offered across all health system levels, with most models implemented at health centers. Common NCDs (including type 2 diabetes and hypertension) were most frequently addressed by these models, followed by common NPs (including depression and anxiety). Conditions and/or services were often integrated into existing primary healthcare, HIV, maternal and child health programs. Services provided for conditions of interest varied and frequency of these services differed across health system levels. Many models demonstrated decentralization of services to lower health system levels, and task shifting to lower cadre providers. CONCLUSIONS: While integrated service design is a promising method to achieve ambitious global goals, little is known about what works, when, and why. This review characterizing care integration programs is an initial step toward developing a structured study of care integration.


Asunto(s)
Diabetes Mellitus Tipo 2 , Enfermedades no Transmisibles , Humanos , Atención a la Salud/métodos , Países en Desarrollo , Salud Mental , Enfermedades no Transmisibles/epidemiología , Enfermedades no Transmisibles/terapia
14.
Commun Chem ; 6(1): 18, 2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36697943

RESUMEN

The spherulitic morphology is considered to be the most common morphology of crystalline materials and is particularly apparent in melt-crystallized products. Yet, historically, the polycrystalline nature of spherulites has hindered successful crystal structure determination. Here, we report the direct structure determination of a clinical drug, vemurafenib (VMN), in compact spherulite form using 3D electron diffraction (3D ED). VMN has four known polymorphs. We first solved the crystal structures of α-, ß-, and γ-VMN from compact spherulites using 3D ED, and the resulting structures were highly consistent with those obtained by single-crystal X-ray diffraction. We then determined the crystal structure of δ-VMN-the least stable polymorph which cannot be cultivated as a single crystal-directly from the compact spherulite sample. We unexpectedly discovered a new polymorph during our studies, denoted as ε-VMN. Single crystals of ε-VMN are extremely thin and not suitable for study by X-ray diffraction. Again, we determined the structure of ε-VMN in a compact spherulite form. This successful structure elucidation of all five VMN polymorphs demonstrates the possibility of directly determining structures from melt-grown compact spherulite samples. Thereby, this discovery will improve the efficiency and broaden the scope of polymorphism research, especially within the field of melt crystallization.

15.
Nat Chem ; 15(2): 230-239, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36357788

RESUMEN

The controllable packing of functional nanoparticles (NPs) into crystalline lattices is of interest in the development of NP-based materials. Here we demonstrate that the size, morphology and symmetry of such supercrystals can be tailored by adjusting the surface dynamics of their constituent NPs. In the presence of excess tetraethylammonium cations, atomically precise [Au25(SR)18]- NPs (where SR is a thiolate ligand) can be crystallized into micrometre-sized hexagonal rod-like supercrystals, rather than as face-centred-cubic superlattices otherwise. Experimental characterization supported by theoretical modelling shows that the rod-like crystals consist of polymeric chains in which Au25 NPs are held together by a linear SR-[Au(I)-SR]4 interparticle linker. This linker is formed by conjugation of two dynamically detached SR-[Au(I)-SR]2 protecting motifs from adjacent Au25 particles, and is stabilized by a combination of CH⋯π and ion-pairing interactions between tetraethylammonium cations and SR ligands. The symmetry, morphology and size of the resulting supercrystals can be systematically tuned by changing the concentration and type of the tetraalkylammonium cations.

16.
Plant Sci ; 326: 111503, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36270512

RESUMEN

Starch accounts for about 80-85 % of the dry weight of grains and determines yield by impact on grain weight. And, the content and composition of starch also determine appearance, eating, cooking and nutritional quality of rice. By coordinating crucial reactions of the primary carbohydrate metabolism in all eukaryotes, fructose-2,6-bisphosphate (Fru-2,6-P2) is a traffic signal in metabolism. However, the metabolic regulation of starch in plant sink tissues by Fru-2,6-P2 remains unclear. Here we isolated rice mutant floury endosperm23 (flo23) which has opaque endosperm and anomalous compound starch grains (SGs). flo23 mutant grains had reduced contents of starch, lipids and proteins. Map-based cloning and genetic complementation experiments showed that FLO23 encodes a cytoplasmic Fructose-6-phosphate-2-kinase/Fructose-2,6-bisphosphatase (F2KP). Mutation of OsF2KP2 decreased Fru-2,6-P2 content in endosperm cells, leading to drastically reduced phosphoenolpyruvate (PEP) and pyruvate contents and disordered glycolysis and energy metabolism. The results imply that OsF2KP2 participates in the glycolytic pathway by providing precursors and energy for synthesis of grain storage compounds.


Asunto(s)
Oryza , Oryza/genética , Oryza/metabolismo , Fosfofructoquinasa-2/genética , Fosfofructoquinasa-2/metabolismo , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Endospermo/metabolismo , Almidón/metabolismo , Fosfotransferasas/metabolismo , Grano Comestible/metabolismo , Metabolismo Energético
17.
J Appl Crystallogr ; 55(Pt 6): 1583-1591, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36570655

RESUMEN

Three-dimensional electron diffraction (3D ED) has become an effective technique to determine the structures of submicrometre- (nanometre-)sized crystals. In this work, energy-filtered 3D ED was implemented using a post-column energy filter in both STEM mode and TEM mode [(S)TEM denoting (scanning) transmission electron microscope]. The setups for performing energy-filtered 3D ED on a Gatan imaging filter are described. The technique and protocol improve the accessibility of energy-filtered 3D ED post-column energy filters, which are available in many TEM laboratories. In addition, a crystal tracking method in STEM mode using high-angle annular dark-field imaging is proposed. This method enables the user to monitor the crystal position while collecting 3D ED data at the same time, allowing a larger tilt range without foregoing any diffraction frames or imposing extra electron dose. In order to compare the differences between energy-filtered and unfiltered 3D ED data sets, three well known crystallized inorganic samples have been studied in detail. For these samples, the final R 1 values improved by 10-30% for the energy-filtered data sets compared with the unfiltered data sets, and the structures became more chemically reasonable. Possible reasons for improvement are also discussed.

18.
Natl Sci Rev ; 9(9): nwab205, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36248071

RESUMEN

The model of ideal fluid flow around a cylindrical obstacle exhibits a long-established physical picture, where originally straight streamlines are deflected over the whole space by the obstacle. Inspired by transformation optics and metamaterials, recent theories have proposed the concept of fluid cloaking, which is able to recover the straight streamlines, as if the obstacle did not exist. However, such a cloak, similar to all previous transformation-optics-based devices, relies on complex metamaterials with inhomogeneous parameters and is difficult to implement. Here we deploy the theory of scattering cancellation and report on the experimental realization of a fluid-flow cloak without metamaterials. This cloak is realized by engineering the geometry of the fluid channel, which effectively cancels the dipole-like scattering of the obstacle. The cloaking effect is demonstrated through the direct observation of recovered straight streamlines in the fluid flow. Our work sheds new light on conventional fluid control and may find application in microfluidic devices.

20.
Gynecol Endocrinol ; 38(11): 949-953, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36097348

RESUMEN

OBJECTIVE: The aim of this retrospective analysis was to explore whether an elevated ALT level before pregnancy is associated with a reduction in live birth rate after IVF-FET. DESIGN: Retrospective observational study. SETTING: Shiyan People's Hospital, China between January 2019 and December 2019. PATIENTS: Women aged ≤ 40 years. INTERVENTION(S): Freeze-thawed embryo transfer (FET). MAIN OUTCOME MEASURE(S): The live birth rate, which was defined as the delivery of a live baby after 24 weeks of gestation. RESULTS: The analysis included 365 FET cycles. There was a significant difference between groups in the live birth rate (p < .05), which was highest for the low ALT tertile and lowest for the high ALT tertile. Multiple regression analysis with adjustment for multiple potential confounders revealed that the odds of live birth were decreased for each one standard deviation increase in ALT (OR = 0.56, 95%CI = 0.42-0.75, p < .0001) and lower for the high ALT tertile than for the low ALT tertile (OR = 0.38, 95%CI = 0.19-0.75, p = .0055). Smooth curve fitting showed an inverse relationship between ALT and live birth rate. CONCLUSION: Our findings indicate that relatively small elevations in baseline serum ALT level can have a clinically relevant impact on the success of FET.


Asunto(s)
Tasa de Natalidad , Transferencia de Embrión , Embarazo , Humanos , Femenino , Índice de Embarazo , Alanina Transaminasa , Estudios Retrospectivos , Nacimiento Vivo/epidemiología , Fertilización In Vitro
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