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1.
Phys Rev Lett ; 132(20): 201901, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38829056

RESUMO

We calculate the next-to-next-to-leading-order (NNLO) QCD radiative correction to the pion electromagnetic form factor with large momentum transfer. We explicitly verify the validity of the collinear factorization to two-loop order for this observable and obtain the respective IR-finite two-loop hard-scattering kernel in the closed form. The NNLO QCD correction turns out to be positive and significant. Incorporating this new ingredient of correction, we then make a comprehensive comparison between the finest theoretical predictions and numerous data for both space- and timelike pion form factors. Our phenomenological analysis provides a strong constraint on the second Gegenbauer moment of the pion light-cone distribution amplitude obtained from recent lattice QCD studies.

2.
J Assist Reprod Genet ; 40(11): 2609-2618, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37728792

RESUMO

PURPOSE: We aimed to compare embryo development, cumulative live birth rate (CLBR), and perinatal outcomes of embryos cultured in 20% and 5% oxygen from days 1 to 3 after insemination. METHODS: This retrospective study included patients who received in vitro fertilization (IVF) treatment between January 2015 and November 2019. Embryos of each patient were cultured at 20% or 5% oxygen from days 1-3 after insemination. The primary outcome was CLBR. Propensity score matching (PSM) was used to balance patients' baseline data in both oxygen groups. RESULTS: In total, 31,566 patients were enrolled. After PSM, the rate of high-quality day 3 embryos was significantly lower in the 20% than in the 5% oxygen group (0.49 ± 0.33 vs 0.51 ± 0.33; adjusted ß = -0.03; 95% confidence interval [CI], -0.03 to -0.02). The CLBR was significantly lower in the 20% than in the 5% oxygen group (58.6% vs. 62.4%; adjusted odds ratio = 0.85; 95% CI, 0.81-0.90). The birthweight and Z score of singletons were significantly higher in the 20% than in the 5% oxygen group (birthweight: 3.30 ± 0.50 vs. 3.28 ± 0.48; adjusted ß = 0.022; 95% CI, 0.004-0.040; Z score: 0.26 ± 1.04 vs. 0.22 ± 1.01; adjusted ß = 0.037; 95% CI, 0.001-0.074). CONCLUSION: Culturing embryos at atmospheric oxygen concentrations from days 1 to 3 compromises embryo quality, reduces CLBR, and affects birthweight. The 5% oxygen concentration is more suitable for embryo culture in IVF laboratories to achieve successful outcomes.


Assuntos
Coeficiente de Natalidade , Fertilização in vitro , Gravidez , Feminino , Humanos , Peso ao Nascer , Estudos Retrospectivos , Inseminação , Nascido Vivo/epidemiologia , Taxa de Gravidez
3.
ACS Macro Lett ; 12(3): 320-324, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36802516

RESUMO

Embolization is often used to block blood supply for controlling the growth of fibroids and malignant tumors, but limited by embolic agents lacking spontaneous targeting and post-treatment removal. So we first adopted nonionic poly(acrylamide-co-acrylonitrile) with an upper critical solution temperature (UCST) to build up self-localizing microcages by inverse emulsification. The results showed that these UCST-type microcages behaved with the appropriate phase-transition threshold value around 40 °C, and spontaneously underwent an expansion-fusion-fission cycle under the stimulus of mild temperature hyperthermia. Given the simultaneous local release of cargoes, this simple but smart microcage is expected to act as a multifunctional embolic agent for tumorous starving therapy, tumor chemotherapy, and imaging.


Assuntos
Hipertermia Induzida , Polímeros , Temperatura , Transição de Fase
4.
Front Endocrinol (Lausanne) ; 13: 985741, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339415

RESUMO

Study question: Is vacuolization in embryos on Days 3 and 4 associated with parent-related factors, stimulation protocols, embryo development, embryo ploidy, pregnancy and neonatal outcomes? Study design size duration: This is a retrospective cohort study that comprised 5,703 embryos from 611 patients who underwent preimplantation genetic testing and time-lapse monitoring of their embryos from August 2017 to September 2021. Main results: Embryo vacuolization on Days 3 and 4 is associated with the LH level on the day of the hCG trigger and the number of retrieved oocytes. Compared to vacuole-negative embryos, the rates of blastocyst formation and good-blastocyst formation was significantly lower in vacuole-positive embryos. We observed no significant difference in the rates of euploidy, implantation, ongoing pregnancy, and live birth between vacuole-positive and vacuole-negative embryos. In vacuole-positive embryos, the embryos of which the vacuole-positive blastomeres were involved in embryo compaction exhibited significantly higher mosaicism rate compared with those of which the vacuole-positive blastomeres were not involved in embryo compaction. Conclusion: Vacuolization in embryos on Days 3 and 4 is associated with reduced blastocyst formation rate and high-quality blastocyst rate. Blastocysts had a low mosaicism rate if the vacuole-containing cells were rejected in compaction process, which supports the hypothesis that exclusion of abnormal blastomeres from compaction is a self-correction mechanism.


Assuntos
Blastocisto , Técnicas de Cultura Embrionária , Gravidez , Feminino , Humanos , Técnicas de Cultura Embrionária/métodos , Estudos Retrospectivos , Desenvolvimento Embrionário/genética , Implantação do Embrião
5.
Phys Rev Lett ; 126(7): 072002, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666478

RESUMO

We present the next-to-next-to-leading order (NNLO) calculation of quark quasiparton distribution functions (PDFs) in the large momentum effective theory. The nontrivial factorization at this order is established explicitly and the full analytic matching coefficients between the quasidistribution and the light-cone distribution are derived. We demonstrate that the NNLO numerical contributions can improve the behavior of the extracted PDFs sizably. With the unprecedented precision study of nucleon tomography at the planned electron-ion collider, high precision lattice QCD simulations with our NNLO results implemented will enable to test the QCD theory and more precise results on the PDFs of nucleons will be obtained.

6.
Ying Yong Sheng Tai Xue Bao ; 32(2): 701-710, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33650380

RESUMO

Forest gap disturbance has important consequences on plant species assemblage, stand structure and ecosystem functions of forests via changing micro-scale heterogeneity and community succession. Here, we reviwed research progress in the effects of forest gap disturbance on forest ecosystem. The effects of forest gap disturbance on plant species assemblage was analyzed based on the intrinsic biological characteristics and external environmental factors. The effects of forest gap disturbance on stand structure was discussed from the perspectives of texture and architecture of plant community. Forest gap disturbance effect on forest ecosystem functions was reviewed. After analyzing the theoretical shortcomings and the key bottleneck of forest ecosystem management practices, the following research directions were proposed, including the methods of determining threshold of forest gap, the mechanism of canopy closure, the effect of forest gap disturbance on forest ecosystem processes, and the relationship between forest gap disturbance and forest productivity. The advantage of forest gap disturbance in accelerating plant species regeneration and structure complexities could provide scientific evidence for enhancing the quality of low yield and low function plantations in China.


Assuntos
Ecossistema , Florestas , China , Árvores
7.
Chem Commun (Camb) ; 56(19): 2837-2840, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32067011

RESUMO

A smart surface with converse temperature-dependent (CTD) wettability was fabricated from an upper critical solution temperature-type (UCST-type) poly(acrylamide-co-acrylonitrile) (P(AAm-co-AN)) copolymer. The obtained surface exhibits a remarkable and reversible hydrophobic-hydrophilic transition depending on temperature with a high response rate. The static water contact angle of the surface decreases from 103° ± 2° to 60° ± 1° as the temperature increases from 30 °C to 80 °C. Further, the wettability of the UCST-type surface shows a positive linear relationship between wettability and temperature. This study for the first time provides an UCST-type smart surface with wettability that decreases by over 35° as the temperature increases by only 20 °C.

8.
J Assist Reprod Genet ; 37(1): 205-212, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31664658

RESUMO

PURPOSE: To investigate the pathogenesis of the recurrent preimplantation embryonic arrest characterized by direct cleavage. METHODS: Two affected individuals underwent time-lapse imaging to observe the cleavage behaviors in their final ICSI attempts. In addition, both patients were subjected to whole-exome sequencing. After the identification of possible causative genes, molecular modeling analyses were used to evaluate the possible effects of candidate mutations on protein secondary structure. RESULTS: All the bipronucleated (2PN) zygotes from both individuals presented multiple abnormal cleavage behaviors, particularly direct cleavage (DC) and subsequent cleavage arrest. Mutation analysis identified one new frameshift mutation c.1521dupC (p.S508Qfs*5) and two missense mutations c.A1117C and c.C1708T (p.T373P and p.R570C, respectively) of the PADI6 gene, which were in the protein-arginine deiminase (PAD) domain and highly conserved. CONCLUSION: This study expands the mutation spectrum of PADI6 and is the first to propose that the preimplantation embryonic arrest with concomitant abnormal cleavage behaviors, especially DC, maybe associated with PADI6 mutations.


Assuntos
Blastocisto/patologia , Desenvolvimento Embrionário , Infertilidade Feminina/etiologia , Mutação , Proteína-Arginina Desiminase do Tipo 6/genética , Adulto , Alelos , Blastocisto/metabolismo , Análise Mutacional de DNA , Feminino , Humanos , Infertilidade Feminina/patologia , Sequenciamento do Exoma
9.
J Med Entomol ; 56(1): 65-71, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30339250

RESUMO

Mosquito trap counts are heavily influenced by environmental factors such as temperature and precipitation. However, some important geographic factors, such as land use and elevation of a particular site, are often either not recorded or simplify not observable. This is a major issue in building a predictive model for the mosquito trap counts over time across a particular region. The collective impact of all unobservable factors for one particular site is estimated by a hidden dimension method. Application to mosquito trap counts in Peel Region has shown that our model can significantly improve the modeling accuracy of the generalized linear model. This method may provide a significantly better characterization of the spatiotemporal distribution of mosquito (Diptera: Culicidae) abundance in areas with green lands or open spaces.


Assuntos
Distribuição Animal , Culicidae , Modelos Biológicos , Animais , Ontário
10.
PeerJ ; 6: e6060, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30588399

RESUMO

Lactobacillus supplementation is beneficial to the barrier function of the intestinal physical barrier in piglets. However, the mechanisms underlying this beneficial function remain largely unknown. Here, we investigated the effects of dietary supplementation with Lactobacillus acidophilus on the performance, intestinal physical barrier functioning, and NOD-like receptors (NLRs) expression in weaned piglets. Sixteen weaned piglets were randomly allocated to two groups. The control group received a corn-soybean basal diet, while the treatment group received the same diet adding 0.1% L. acidophilus, for 14 days. As a result, dietary L. acidophilus supplementation was found to increase the average daily gain (ADG) (P < 0.05), reduced serum diamine oxidase (DAO) activity (P < 0.05), increased the mRNA expression and protein abundance of occludin in the jejunum and ileum (P < 0.01), reduced the mRNA levels of NOD1 (P < 0.01), receptor interacting serine/threonine kinase 2 (RIPK2) (P < 0.05), nuclear factor κB (NF-κB) (P < 0.01), NLR family pyrin domain containing 3 (NLRP3) (P < 0.01), caspase-1 (P < 0.01), interleukin 1ß (IL-1ß) (P < 0.05) and IL-18 (P < 0.01) in the jejunum tissues of the weaned pigs. The expression of NLRP3 (P < 0.05), caspase-1 (P < 0.01), IL-1ß (P < 0.05) and IL-18 (P < 0.05) was also reduced in the ileum tissues of the weaned pigs. These results showed that L. acidophilus supplementation improves the growth performance, enhances the intestinal physical barrier function, and inhibits the expression of NOD1 and NLRP3 signaling-pathway-related genes in jejunum and ileum tissues. They also suggest that L. acidophilus enhances the intestinal physical barrier functioning by inhibiting IL-1ß and IL-18 pro-inflammatory cytokines via the NOD1/NLRP3 signaling pathway in weaned piglets.

11.
Phys Chem Chem Phys ; 20(46): 29012-29017, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30238943

RESUMO

As a common physicochemical phenomenon, protonation can cause molecules, atoms or ions with lone-pair electrons to become charged, and can further cause some changes in their physical and chemical properties. Our study first focused on the molecular protonation process and accompanying transitions of the oil/water interface properties in an electric field. The relationship between the protonation degree increment and applied voltage was proposed as a guide for controlling the protonation via applying an electric field. Besides the protonation degree, the water solubility of the oily target molecule obviously increased at 30 V for 600 s along with electric field-driven protonation. At the same time, the electrical conductivity and the underwater interface wettability of oil phase transitioned. These property transitions are anticipated to guide the further improvement and updating of promising protonation functions.

12.
BMC Microbiol ; 16(1): 273, 2016 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-27832756

RESUMO

BACKGROUND: A newly isolated L. acidophilus strain has been reported to have potential anti-inflammatory activities against lipopolysaccharide (LPS) challenge in piglet, while the details of the related inflammatory responses are limited. Here we aimed to analysis the ability of L. acidophilus to regulate inflammatory responses and to elucidate the mechanisms involved in its anti-inflammatory activity. RESULTS: The ETEC (enterotoxigenic Escherichia coli) K88-induced up-regulations of IL-1ß, IL-8 and TNF-α were obviously inhibited by L. acidophilus while IL-10 was significantly increased. Moreover, L. acidophilus down-regulated pattern recognition receptors TLR (Toll-like receptor) 2 and TLR4 expression in both spleen and mesenteric lymph nodes of ETEC-challenged piglets, in accompanied with the reduced phosphorylation levels of nuclear factor kappa B (NF-κB) p65 and mitogen-activated protein kinase (MAPK) p38 as well in spleen of ETEC-infected piglets. Furthermore, L.acidophilus significantly increased the expression of the negative regulators of TLRs signaling, including Tollip, IRAK-M, A20 and Bcl-3 in spleen of ETEC-challenged piglets. CONCLUSIONS: Our findings suggested that L. acidophilus regulated inflammatory response to ETEC via impairing both NF-κB and MAPK signaling pathways in piglets.


Assuntos
Escherichia coli Enterotoxigênica/fisiologia , Inflamação/microbiologia , Lactobacillus acidophilus/fisiologia , NF-kappa B/metabolismo , Fator de Transcrição RelA/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Citocinas/sangue , Citocinas/metabolismo , Modelos Animais de Doenças , Infecções por Escherichia coli/prevenção & controle , Feminino , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Lipopolissacarídeos/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Probióticos , Transdução de Sinais , Suínos , Receptor 2 Toll-Like/biossíntese , Receptor 2 Toll-Like/metabolismo , Fator de Transcrição RelA/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
13.
Chem Commun (Camb) ; 51(10): 1823-5, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25519843

RESUMO

Using the widely available DMSO as the formylation reagent under oxidative conditions, an efficient Cu-catalyzed C3-formylation reaction of imidazo[1,2-a]pyridine C-H bonds to directly generate structurally sophisticated 3-formyl imidazo[1,2-a]pyridine derivatives has been developed. The reaction proceeded to generate products in good yields, and used the environmentally friendly molecular oxygen as the oxidant.


Assuntos
Cobre/química , Dimetil Sulfóxido/química , Imidazóis/química , Oxigênio/química , Piridinas/síntese química , Catálise , Ligação de Hidrogênio , Oxirredução , Piridinas/química
14.
IEEE Trans Pattern Anal Mach Intell ; 30(1): 147-59, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18000331

RESUMO

Traditional stereo matching algorithms are limited in their ability to produce accurate results near depth discontinuities, due to partial occlusions and violation of smoothness constraints. In this paper, we use small baseline multi-flash illumination to produce a rich set of feature maps that enable acquisition of discontinuity preserving point correspondences. First, from a single multi-flash camera, we formulate a qualitative depth map using a gradient domain method that encodes object relative distances. Then, in a multiview setup, we exploit shadows created by light sources to compute an occlusion map. Finally, we demonstrate the usefulness of these feature maps by incorporating them into two different dense stereo correspondence algorithms, the first based on local search and the second based on belief propagation. Experimental results show that our enhanced stereo algorithms are able to extract high quality, discontinuity preserving correspondence maps from scenes that are extremely challenging for conventional stereo methods. We also demonstrate that small baseline illumination can be useful to handle specular reflections in stereo imagery. Different from most existing active illumination techniques, our method is simple, inexpensive, compact, and requires no calibration of light sources.


Assuntos
Algoritmos , Inteligência Artificial , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Iluminação/métodos , Reconhecimento Automatizado de Padrão/métodos , Fotogrametria/métodos , Fotometria/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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