118 research outputs found
Riemannian Adaptive Regularized Newton Methods with H\"older Continuous Hessians
This paper presents strong worst-case iteration and operation complexity
guarantees for Riemannian adaptive regularized Newton methods, a unified
framework encompassing both Riemannian adaptive regularization (RAR) methods
and Riemannian trust region (RTR) methods. We comprehensively characterize the
sources of approximation in second-order manifold optimization methods: the
objective function's smoothness, retraction's smoothness, and subproblem
solver's inexactness. Specifically, for a function with a -H\"older
continuous Hessian, when equipped with a retraction featuring a -H\"older
continuous differential and a -inexact subproblem solver, both RTR and
RAR with regularization (where )
locate an -approximate second-order
stationary point within at most
iterations and at most
Hessian-vector products. These complexity results are novel and sharp, and
reduce to an iteration complexity of and an operation
complexity of when
Learning with few samples in deep learning for image classification, a mini-review
Deep learning has achieved enormous success in various computer tasks. The excellent performance depends heavily on adequate training datasets, however, it is difficult to obtain abundant samples in practical applications. Few-shot learning is proposed to address the data limitation problem in the training process, which can perform rapid learning with few samples by utilizing prior knowledge. In this paper, we focus on few-shot classification to conduct a survey about the recent methods. First, we elaborate on the definition of the few-shot classification problem. Then we propose a newly organized taxonomy, discuss the application scenarios in which each method is effective, and compare the pros and cons of different methods. We classify few-shot image classification methods from four perspectives: (i) Data augmentation, which contains sample-level and task-level data augmentation. (ii) Metric-based method, which analyzes both feature embedding and metric function. (iii) Optimization method, which is compared from the aspects of self-learning and mutual learning. (iv) Model-based method, which is discussed from the perspectives of memory-based, rapid adaptation and multi-task learning. Finally, we conduct the conclusion and prospect of this paper
Sirt6 depletion causes spindle defects and chromosome misalignment during meiosis of mouse oocyte
Sirt6, a member of the sirtuin family of NAD-dependent protein deacetylases, has been implicated in multiple biological processes. However, the roles of Sirt6 in meiosis have not been addressed. In the present study, by employing knockdown analysis in mouse oocytes, we evaluated the effects of Sirt6 on meiotic apparatus. We found that specific depletion of Sirt6 results in disruption of spindle morphology and chromosome alignment in oocytes. Consistent with this observation, incidence of aneuploidy is also markedly increased in Sirt6-depleted oocytes. Furthermore, confocal scanning showed that kinetochore-microtubule interaction, an important mechanism controlling chromosome segregation, is severely impaired in metaphase oocytes following Sirt6 knockdown. Unexpectedly, we discovered that Sirt6 modulates the acetylation status of histone H4K16 as their knockdown specifically induces the hyperacetylation of H4K16 in oocytes, which may be associated with the defective phenotypes described above via altering kinetochore function. Altogether, our data reveal a novel function of Sirt6 during oocyte meiosis and indicate a pathway regulating meiotic apparatus
Teenage Pregnancy: The Case for Prevention and Increased Quality of Life in Waco, Texas
In 2011, Texas was ranked 5th in the nation for total teen births rates amongst females, ages 15-19 (Department of Health and Human Resources 2011). Compared to the national average in the United States of 31.3 per one thousand, in 2011 46.9 per one thousand of Texas teens became pregnant (Appendix A). Teen Pregnancy is a very real issue in Texas, and the Waco community has found itself in the forefront of this fight.
In 2007, the Waco Foundation, a community-based foundation that supports the Waco and McLennan County areas through grant making and philanthropy, commissioned a Quality of Life Report to be conducted within their community. Children in McLennan County were discovered to have an overall quality of life score, a measure of physical health status and disease, of 41.67%. Dispersed among the countyās zip codes, this score represented a 57% disparity in scores between the lowest and highest zip codes in the county (Smith, Romero and Alonzo 2009). In searching for causes for this disparity, the Quality of Life Report found a correlation between low early childhood quality of life and teenage parents (Smith, Romero and Alonzo 2009).
This led to the community accepting the urgency of the issue and creating the SmartBabies Early Childhood Initiative. It is SmartBabiesā mission to raise the quality of life for all children within McLennan County. Because of this, the SmartBabies Steering Committee, encompassing representatives from health care, business, and early childhood development sectors, has determined the best way to address low quality of life caused by teen pregnancy is to prevent teenage pregnancy altogether by introducing āpreventativeā programming (SmartBabies Community Update, 2013).
The Waco Foundation SmartBabies Early Childhood Initiative commissioned this study to provide an analysis of the relative costs of teen pregnancy prevention as opposed to reactive support in the Waco, Texas community and to support the communityās current and future projected programming activities. The analysis includes a literature review, collection of secondary data, qualitative interviews, and an inclusive presentation of findings to SmartBabies, the Waco Foundation and its stakeholders, showing the positive impacts as a result of Waco proactively reducing teen pregnancy.Waco Foundation's Early Childhood Initiative SmartBabie
Energy-effective offloading scheme in UAV-assisted C-RAN system
In this paper, we aim to minimize the total power of all the Internet of Things devices (IoTDs) by jointly optimizing user association, computation capacity, transmit power, and the location of unmanned aerial vehicles (UAVs) in an UAV-assisted cloud radio access network (C-RAN). In order to solve this non-convex problem, we propose an effective algorithm by solving four subproblems iteratively. For the user association and the computation capacity subproblems, the non-convex constraints are relaxed and the optimal solutions are obtained. For the transmit power control and the location planning subproblems, successive convex approximation (SCA) technique is used to transform the non-convex constraints into convex ones. Moreover, to obtain the suboptimal solutions, slack variables are also introduced to deal with the feasibility-check problems. The simulation results demonstrate that the proposed algorithm can greatly reduce the total power consumption of IoTDs
Effects of different gonadotropin preparations in GnRH antagonist protocol for patients with polycystic ovary syndrome during IVF/ICSI: a retrospective cohort study
PurposeTo compare the effects of recombinant FSH alfa (rFSH-alfa), rFSH-beta, highly purified human menopausal gonadotropin (HP-hMG) and urinary FSH (uFSH) in women with polycystic ovarian syndrome who have undertaken the GnRH antagonist protocol during IVF/ICSI treatment.MethodA single-center retrospective cohort study including women with PCOS who received the GnRH antagonist protocol from January 2019 to July 2022 was conducted. Patients were divided into rFSH-alfa group, HP-hMG group, uFSH group, and rFSH-beta group, and the number of oocytes retrieved, clinical pregnancy rate of the fresh cycle (primary outcomes), embryo quality, and severe OHSS rate (secondary outcomes) were compared.ResultsNo statistical differences were found among the four groups in fresh cycle clinical pregnancy rate (p=0.426), nor in the subgroup analyses. The HP-hMG group had a smaller number of oocytes retrieved and a higher high-quality D3 embryo rate than the three FSH groups (p<0.05). No statistical differences were found among the four groups in the severe OHSS rate (p=0.083).ConclusionFor women with PCOS undergoing the GnRH antagonist protocol, the clinical pregnancy rates of fresh IVF/ICSI-ET cycle are similar for all four types of Gn. With a lower risk of OHSS and a similar number of high-quality and available embryos, HP-hMG may have an advantage in the PCOS population
Dielectric relaxation, resonance and scaling behaviors in Sr3Co2Fe24O41 hexaferrite
The dielectric properties of Z-type hexaferrite Sr(3)Co(2)Fe(24)O(41) (SCFO) have been investigated as a function of temperature from 153 to 503āK between 1 and 2āGHz. The dielectric responses of SCFO are found to be frequency dependent and thermally activated. The relaxation-type dielectric behavior is observed to be dominating in the low frequency region and resonance-type dielectric behavior is found to be dominating above 10(8)āHz. This frequency dependence of dielectric behavior is explained by the damped harmonic oscillator model with temperature dependent coefficients. The imaginary part of impedance (Zā³) and modulus (Mā³) spectra show that there is a distribution of relaxation times. The scaling behaviors of Zā³ and Mā³ spectra further suggest that the distribution of relaxation times is temperature independent at low frequencies. The dielectric loss spectra at different temperatures have not shown a scaling behavior above 10(8)āHz. A comparison between the Zā³ and the Mā³ spectra indicates that the short-range charges motion dominates at low temperatures and the long-range charges motion dominates at high temperatures. The above results indicate that the dielectric dispersion mechanism in SCFO is temperature independent at low frequencies and temperature dependent at high frequencies due to the domination of resonance behavior
Vertical Interface Induced Dielectric Relaxation in Nanocomposite (BaTiO3)1-x:(Sm2O3)x Thin Films
Vertical interfaces in vertically aligned nanocomposite thin films have been approved to be an effective method to manipulate functionalities. However, several challenges with regard to the understanding on the physical process underlying the manipulation still remain. In this work, because of the ordered interfaces and large interfacial area, heteroepitaxial (BaTiO(3))(1-x):(Sm(2)O(3))(x) thin films have been fabricated and used as a model system to investigate the relationship between vertical interfaces and dielectric properties. Due to a relatively large strain generated at the interfaces, vertical interfaces between BaTiO(3) and Sm(2)O(3) are revealed to become the sinks to attract oxygen vacancies. The movement of oxygen vacancies is confined at the interfaces and hampered by the misfit dislocations, which contributed to a relaxation behavior in (BaTiO(3))(1-x):(Sm(2)O(3))(x) thin films. This work represents an approach to further understand that how interfaces influence on dielectric properties in oxide thin films
Face mask integrated with flexible and wearable manganite oxide respiration sensor
Face masks are key personal protective equipment for reducing exposure to viruses and other environmental hazards such as air pollution. Integrating flexible and wearable sensors into face masks can provide valuable insights into personal and public health. The advantages that a breath-monitoring face mask requires, including multi-functional sensing ability and continuous, long-term dynamic breathing process monitoring, have been underdeveloped to date. Here, we design an effective human breath monitoring face mask based on a flexible La0.7Sr0.3MnO3 (LSMO)/Mica respiration sensor. The sensorās capabilities and systematic measurements are investigated under two application scenes, namely clinical monitoring mode and daily monitoring mode, to monitor, recognise, and analyse different human breath status, i.e., cough, normal breath, and deep breath. This sensing system exhibits super-stability and multi-modal capabilities in continuous and long-time monitoring of the human breath. We determine that during monitoring human breath, thermal diffusion in LSMO is responsible for the change of resistance in flexible LSMO/Mica sensor. Both simulated and experimental results demonstrate good discernibility of the flexible LSMO/Mica sensor operating at different breath status. Our work opens a route for the design of novel flexible and wearable electronic devices
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