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The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei ^{3}H and ^{3}He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, 0.6
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Freon is widely used in daily life, which is usually absorbed through the respiratory tract and causes clinical manifestations mainly in the cardiovascular system and neurological damage. Now, we analyze the clinical data, diagnosis, treatment and prognosis of two cases of freon poisoning in Affiliated Dongyang People's Hospital of Wenzhou Medical University to improve the clinicians' understanding of freon poisoning and to avoid missed diagnosis and misdiagnosis.
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Clorofluorcarbonetos , Intoxicação , Humanos , PrognósticoRESUMO
Bromadiolone is still often used in life as a poisonous rodent agent. Bromadiolone poisoning is often manifested as coagulation dysfunction, resulting in organ bleeding, including cerebral hemorrhage, intestinal bleeding, abdominal hemorrhage, etc. At present, no case of intestinal necrosis caused by bromadiolone poisoning have been reported. This article reviewed one case of intestinal necrosis and severe coagulation dysfunction, and finally confirmed bromadiolone poisoning by poison detection. The patient recovered and was discharged after surgery, vitamin K injection, plasma transfusion and other treatment methods.
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4-Hidroxicumarinas , Transtornos da Coagulação Sanguínea , Intoxicação , Rodenticidas , Humanos , Transtornos da Coagulação Sanguínea/induzido quimicamente , Transfusão de Componentes Sanguíneos , Hemorragia , Necrose , PlasmaRESUMO
Objective: To establish an intelligent registration algorithm under the framework of original-mirror alignment algorithm to construct three-dimensional(3D) facial midsagittal plane automatically. Dynamic Graph Registration Network (DGRNet) was established to realize the intelligent registration, in order to provide a reference for clinical digital design and analysis. Methods: Two hundred clinical patients without significant facial deformities were collected from October 2020 to October 2022 at Peking University School and Hospital of Stomatology. The DGRNet consists of constructing the feature vectors of key points in point original and mirror point clouds (X, Y), obtaining the correspondence of key points, and calculating the rotation and translation by singular value decomposition. Original and mirror point clouds were registrated and united. The principal component analysis (PCA) algorithm was used to obtain the DGRNet alignment midsagittal plane. The model was evaluated based on the coefficient of determination (R2) index for the translation and rotation matrix of test set. The angle error was evaluated on the 3D facial midsagittal plane constructed by the DGRNet alignment midsagittal plane and the iterative closet point(ICP) alignment midsagittal plane for 50 cases of clinical facial data. Results: The average angle error of the DGRNet alignment midsagittal plane and ICP alignment midsagittal plane was 1.05°±0.56°, and the minimum angle error was only 0.13°. The successful detection rate was 78%(39/50) within 1.50° and 90% (45/50)within 2.00°. Conclusions: This study proposes a new solution for the construction of 3D facial midsagittal plane based on the DGRNet alignment method with intelligent registration, which can improve the efficiency and effectiveness of treatment to some extent.
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Objective: To determine whether the adenine base editor (ABE7.10) can be used to fix harmful mutations in the human G6PC3 gene. Methods: To investigate the safety of base-edited embryos, off-target analysis by deep sequencing was used to examine the feasibility and editing efficiency of various sgRNA expression vectors. The human HEK293T mutation models and human embryos were also used to test the feasibility and editing efficiency of correction. Results: â The G6PC3(C295T) mutant cell model was successfully created. â¡In the G6PC3(C295T) mutant cell model, three distinct Re-sgRNAs were created and corrected, with base correction efficiency ranging from 8.79% to 19.56% . ⢠ABE7.10 could successfully fix mutant bases in the human pathogenic embryo test; however, base editing events had also happened in other locations. ⣠With the exception of one noncoding site, which had a high safety rate, deep sequencing analysis revealed that the detection of 32 probable off-target sites was <0.5% . Conclusion: This study proposes a new base correction strategy based on human pathogenic embryos; however, it also produces a certain nontarget site editing, which needs to be further analyzed on the PAM site or editor window.
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Sistemas CRISPR-Cas , Edição de Genes , Humanos , Adenina , Células HEK293 , Mutação , Glucose-6-Fosfatase/genética , Glucose-6-Fosfatase/metabolismoRESUMO
Objective: To evaluate the effect of health management service on hypertension patients (HMSFHP) under the framework of the Basic Public Health Service Project by using regression discontinuity design. Methods: The participants were enrolled from an observational cohort survey in 2015 and followed up was conducted in 2019. The participants with SBP 130-150 mmHg and/or DBP 80-100 mmHg in the baseline survey of the cohort in 2015 were included in the present study. Additionally, we obtained the dates of participants receiving HMSFHP and their blood pressure data from follow-up records, physical examination records and telephone interview. The participants were divided into intervention group and control group based on the cutoff points, i.e. SBP ≥140 mmHg and/or DBP ≥90 mmHg. The local linear regression model were used to estimate the effect of HMSFHP on reducing blood pressure of the participants. Results: After adjusting for age, sex and time length of receiving HMSFHP, the results of the model including participants with 80-100 mmHg for DBP in 2015 indicated that, for the participants who received HMSFHP, the DBP decreased by 6.66 mmHg from 2015 to 2019. For the participants with SBP 130-150 mmHg in 2015, the reduction estimate of the model was -6.17 mmHg, the difference was not significant (P=0.178), suggesting that receiving HMSFHP did not cause change in SBP for the participants who received HMSFHP. Conclusion: Receiving HMSFHP had effect to reduce DBP, and HMSFHP had a positive effect on the control of blood pressure in patients with hypertension.
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Hipertensão , Humanos , Pressão Sanguínea , Serviços de Saúde , Modelos Lineares , Exame FísicoRESUMO
The stomatognathic system is an organic combination of bone, dentition, joints, masticatory muscles and innervation nerves. It is an organ system for the human body to perform mastication, speech, swallowing and other important functions. Due to the complex anatomical structure of stomatognathic system and ethical limitations, it is difficult to directly measure the movement and force by using the biomechanical experimental methods. Multi-body system dynamics is an important tool to study the kinetics and force of a multi-body system, which consists of several objects with relative motion. We can use the method of multi-body system dynamics simulation in engineering to study the movement, soft tissue deformation and force transfer of this complex stomatognathic system. This paper briefly introduces the history and application methods of multi-body system dynamics and the commonly used modeling methods. The application and research progress of multi-body system dynamics modeling methods in the field of stomatology was emphatically summarized, development prospects of current research and difficulties were put forward.
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One of the brilliant ideas of John Spence when he saw the first diffraction patterns from the Linac Coherent Light Source was that one could solve the crystallographic phase problem by utilising the intensities between Bragg peaks. Because these intensities are due to the Fourier transform of the shape of the crystal, the approach came to be known as "shape-transform phasing." Shape-transform phasing was developed over the next ten years and formed the basis for many other interesting ideas and pursuits. Here we describe the current best implementation of the original idea using a lattice occupancy formalism and show that certain types of crystal defects can also be modelled via this approach, allowing the molecular structure to be recovered from the additional information offered by the inter-Bragg intensities from these crystal defects.
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The proton is one of the main building blocks of all visible matter in the Universe1. Among its intrinsic properties are its electric charge, mass and spin2. These properties emerge from the complex dynamics of its fundamental constituents-quarks and gluons-described by the theory of quantum chromodynamics3-5. The electric charge and spin of protons, which are shared among the quarks, have been investigated previously using electron scattering2. An example is the highly precise measurement of the electric charge radius of the proton6. By contrast, little is known about the inner mass density of the proton, which is dominated by the energy carried by gluons. Gluons are hard to access using electron scattering because they do not carry an electromagnetic charge. Here we investigated the gravitational density of gluons using a small colour dipole, through the threshold photoproduction of the J/ψ particle. We determined the gluonic gravitational form factors of the proton7,8 from our measurement. We used a variety of models9-11 and determined, in all cases, a mass radius that is notably smaller than the electric charge radius. In some, but not all cases, depending on the model, the determined radius agrees well with first-principle predictions from lattice quantum chromodynamics12. This work paves the way for a deeper understanding of the salient role of gluons in providing gravitational mass to visible matter.
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With the accumulation of research evidence and clinical experience, an increasing number of patients benefit from vascular recanalization therapies. Although successful recanalization of the occluded artery has been achieved, neurological deficits persist after endovascular treatment, which defined as"futile reperfusion". Compared with the successful recanalization, successful reperfusion predicts final infarct size and clinical outcome more accurately. At present, the known influencing factors of futile reperfusion include older age, female, high baseline National Institute of Health stroke scale (NIHSS) score, hypertension, diabetes, atrial fibrillation, reperfusion treatment strategy, large infarction core volume, and collateral circulation status. The incidence of futile reperfusion in China is significantly higher than that in western population. However, few studies focused on its mechanism and influencing factors. To date, many clinical studies have attempted to reduce the occurrence of futile recanalization regarding antiplatelet therapy, blood pressure management and treatment process improvement. However, only one effective measure has been achieved in blood pressure management: systolic blood pressure control below 120 mmHg (1 mmHg=0.133 kPa) should be avoided after successful recanalization. Therefore, future studies are warranted to promote the establishment and maintenance of collateral circulation, as well as neuroprotective therapy.
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Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , Acidente Vascular Cerebral/terapia , Atenção , China , Resultado do Tratamento , Isquemia Encefálica/terapia , Estudos RetrospectivosRESUMO
Objective: To summarize the experience in diagnosis and treatment of 45, X Turner syndrome (TS) with gonadal Y chromosome mosaicism and bilateral gonadoblastoma (Gb) secreting human chorionic gonadotrophin(HCG). Methods: A female patient aged 5 years and 3 months was admitted to the hospital with a complaint of "enlarged breasts for 27 months, and elevated blood ß-HCG for 8 months". The clinical data were summarized, and related literature up to March 2022 with the key words"Turner syndrome" "Gonadoblastoma" "Y chromosome" "human chorionic gonadotropin" "precocious" in PubMed, CNKI and Wanfang databases were reviewed. Results: The girl went to the local hospital for 2-month breast development at age of 3 years, and was found with a heart murmur diagnosed with "pulmonary venous malformation and atrial septal defect (secondary foramen type)". Surgical correction was performed. She experienced the progressive breast development, rapid linear growth and markedly advanced skeletal age, which cannot be explained by partial activation in the hypothalamic-pituitary-gonadal axis determined at the age of 3 years and 7 months in local hospital. Then whole-exome sequencing revealed chromosome number abnormality 45, X, which was confirmed by Karyotyping. At the age of 4 years and 6 months, serum ß-HCG was found to be elevated (24.9 U/L) with no lesion found at the local hospital. On physical examination, she was found with breast development, pubic hair development and clitoromegaly with elevated serum testosterone (1.96 µg/L) and ß-HCG (32.3 U/L). Sex determining region Y(SRY) gene was negative in peripheral blood sample. Thoracic and abdominal CT, head and pelvic magnetic resonance imaging were normal. Exploratory laparotomy confirmed the presence of a left adnexal tumor and a right fibrous streak gonad. During surgery, simultaneous samples of bilateral gonadal and peripheral venous blood were obtained and serum ß-HCG, estradiol and testosteron concentrations was higher to lower from left gonadal venous blood, right gonadal venous blood, to peripheral venous blood. Bilateral gonadectomy was performed. Histopathology revealed bilateral gonadoblastomas. SRY was positive in bilateral gonadal tissues. After surgery, serum E2, testerone and ß-HCG returned to normal. So far 4 cases of HCG-secreting gonadoblastoma had been reported worldwide. The phenotypes of the 4 cases were all female, with virilization or amenorrhea, and the preoperative peripheral blood ß-HCG concentrations were 74.4, 5.0, 40 456.0, and 42.4 U/L, respectively. Conclusions: There is a high risk of Gb in TS with Y chromosome components. Gb is infrequently presented with breast development, and Gb associated with HCG secretion is rare. Karyotyping should be performed in a phenotypic female with masculinization, and virilization in TS indicates the presence of Y chromosome material with concurrent androgen secreting tumors.
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Gonadoblastoma , Neoplasias Ovarianas , Síndrome de Turner , Humanos , Feminino , Pré-Escolar , Gonadoblastoma/complicações , Gonadoblastoma/genética , Gonadoblastoma/cirurgia , Síndrome de Turner/complicações , Virilismo , Gonadotropina CoriônicaRESUMO
The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state. A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities1 that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities2 map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades2. Here we report measurements of the proton's electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton's electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distribution of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.
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When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon-nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly energetic nucleons referred to as short-range correlations (SRCs). SRCs are an important but relatively poorly understood part of nuclear structure1-3, and mapping out the strength and the isospin structure (neutron-proton (np) versus proton-proton (pp) pairs) of these virtual excitations is thus critical input for modelling a range of nuclear, particle and astrophysics measurements3-5. Two-nucleon knockout or 'triple coincidence' reactions have been used to measure the relative contribution of np-SRCs and pp-SRCs by knocking out a proton from the SRC and detecting its partner nucleon (proton or neutron). These measurements6-8 have shown that SRCs are almost exclusively np pairs, but they had limited statistics and required large model-dependent final-state interaction corrections. Here we report on measurements using inclusive scattering from the mirror nuclei hydrogen-3 and helium-3 to extract the np/pp ratio of SRCs in systems with a mass number of three. We obtain a measure of the np/pp SRC ratio that is an order of magnitude more precise than previous experiments, and find a marked deviation from the near-total np dominance observed in heavy nuclei. This result implies an unexpected structure in the high-momentum wavefunction for hydrogen-3 and helium-3. Understanding these results will improve our understanding of the short-range part of the nucleon-nucleon interaction.
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We report high-precision measurements of the deeply virtual Compton scattering (DVCS) cross section at high values of the Bjorken variable x_{B}. DVCS is sensitive to the generalized parton distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton form factors (CFFs) of the nucleon as a function of x_{B}, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.
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In order to investigate developmental coordination disorder (DCD) of kindergarten children in Zhejiang province, 200 ordinary kindergartens were randomly selected by stratified random sampling in 11 prefecture-level cities of Zhejiang Province, and 38 900 children from 1 000 classes in each grade were then randomly selected into the study from June 2019 to December 2019. The Little DCD Questionnaire and a self-designed questionnaire were used to screen the DCD of those children. There were 36 807 valid questionnaires, and 6.50% (2 391/36 807) of them were positive results. The results showed that boy, age ≤5 years, overweight or obesity, left handedness, comorbidity with motor or developmental disorders and premature infants were risk factors of DCD in children. As for parents and families, maternal gestational age<20 years, maternal overweight or obesity before pregnancy, low-middle level education of parents, direct family and low income of family were also associated with DCD in children. Therefore, it is necessary to conduct early prevention and intervention strategies targeting on identified risk factors among relevant population.
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Transtornos das Habilidades Motoras , Sobrepeso , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Transtornos das Habilidades Motoras/epidemiologia , Obesidade , Gravidez , Fatores de Risco , Instituições Acadêmicas , Adulto JovemRESUMO
Single-particle imaging with X-ray free-electron lasers depends crucially on algorithms that merge large numbers of weak diffraction patterns despite missing measurements of parameters such as particle orientations. The expand-maximize-compress (EMC) algorithm is highly effective at merging single-particle diffraction patterns with missing orientation values, but most implementations exhaustively sample the space of missing parameters and may become computationally prohibitive as the number of degrees of freedom extends beyond orientation angles. This paper describes how the EMC algorithm can be modified to employ Metropolis Monte Carlo sampling rather than grid sampling, which may be favorable for reconstruction problems with more than three missing parameters. Using simulated data, this variant is compared with the standard EMC algorithm.
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Algoritmos , Elétrons , Lasers , Método de Monte CarloRESUMO
The ratio of the nucleon F_{2} structure functions, F_{2}^{n}/F_{2}^{p}, is determined by the MARATHON experiment from measurements of deep inelastic scattering of electrons from ^{3}H and ^{3}He nuclei. The experiment was performed in the Hall A Facility of Jefferson Lab using two high-resolution spectrometers for electron detection, and a cryogenic target system which included a low-activity tritium cell. The data analysis used a novel technique exploiting the mirror symmetry of the two nuclei, which essentially eliminates many theoretical uncertainties in the extraction of the ratio. The results, which cover the Bjorken scaling variable range 0.19
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We present new precision measurements of the elastic electron-proton scattering cross section for momentum transfer (Q^{2}) up to 15.75 (GeV/c)^{2}. Combined with existing data, these provide an improved extraction of the proton magnetic form factor at high Q^{2} and double the range over which a longitudinal or transverse separation of the cross section can be performed. The difference between our results and polarization data agrees with that observed at lower Q^{2} and attributed to hard two-photon exchange (TPE) effects, extending to 8 (GeV/c)^{2} the range of Q^{2} for which a discrepancy is established at >95% confidence. We use the discrepancy to quantify the size of TPE contributions needed to explain the cross section at high Q^{2}.
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Fluorine is one of the most interesting elements in nuclear astrophysics, where the ^{19}F(p,α)^{16}O reaction is of crucial importance for Galactic ^{19}F abundances and CNO cycle loss in first generation Population III stars. As a day-one campaign at the Jinping Underground Nuclear Astrophysics experimental facility, we report direct measurements of the essential ^{19}F(p,αγ)^{16}O reaction channel. The γ-ray yields were measured over E_{c.m.}=72.4-344 keV, covering the Gamow window; our energy of 72.4 keV is unprecedentedly low, reported here for the first time. The experiment was performed under the extremely low cosmic-ray-induced background environment of the China JinPing Underground Laboratory, one of the deepest underground laboratories in the world. The present low-energy S factors deviate significantly from previous theoretical predictions, and the uncertainties are significantly reduced. The thermonuclear ^{19}F(p,αγ)^{16}O reaction rate has been determined directly at the relevant astrophysical energies.