Drone-based small object detection is of great significance in practical applications such as military actions, disaster rescue, transportation, etc. However, the severe scale differences in objects captured by drones...Drone-based small object detection is of great significance in practical applications such as military actions, disaster rescue, transportation, etc. However, the severe scale differences in objects captured by drones and lack of detail information for small-scale objects make drone-based small object detection a formidable challenge. To address these issues, we first develop a mathematical model to explore how changing receptive fields impacts the polynomial fitting results. Subsequently, based on the obtained conclusions, we propose a simple but effective Hybrid Receptive Field Network (HRFNet), whose modules include Hybrid Feature Augmentation (HFA), Hybrid Feature Pyramid (HFP) and Dual Scale Head (DSH). Specifically, HFA employs parallel dilated convolution kernels of different sizes to extend shallow features with different receptive fields, committed to improving the multi-scale adaptability of the network;HFP enhances the perception of small objects by capturing contextual information across layers, while DSH reconstructs the original prediction head utilizing a set of high-resolution features and ultrahigh-resolution features. In addition, in order to train HRFNet, the corresponding dual-scale loss function is designed. Finally, comprehensive evaluation results on public benchmarks such as VisDrone-DET and TinyPerson demonstrate the robustness of the proposed method. Most impressively, the proposed HRFNet achieves a mAP of 51.0 on VisDrone-DET with 29.3 M parameters, which outperforms the extant state-of-the-art detectors. HRFNet also performs excellently in complex scenarios captured by drones, achieving the best performance on the CS-Drone dataset we built.展开更多
Background: Recent studies have revealed that noncoding RNAs play important regulatory roles in the formation of endometrial receptivity.Circular RNAs(circRNAs) are a universally expressed noncoding RNA species that h...Background: Recent studies have revealed that noncoding RNAs play important regulatory roles in the formation of endometrial receptivity.Circular RNAs(circRNAs) are a universally expressed noncoding RNA species that have been recently proposed to act as miRNA sponges that directly regulate expression of target genes or parental genes.Results: We used Illumina Solexa technology to analyze the expression profiles of circRNAs in the endometrium from three goats at gestational day 5(pre-receptive endometrium,PE) and three goats at gestational day 15(receptive endometrium,RE).Overall,21,813 circRNAs were identified,of which 5,925 circRNAs were specific to the RE and 9,078 were specific to the PE,which suggested high stage-specificity.Further analysis found 334 differentially expressed circRNAs in the RE compared with PE(P < 0.05).The analysis of the circRNA-miRNA interaction network further supported the idea that circRNAs act as miRNA sponges to regulate gene expression.Moreover,some circRNAs were regulated by estrogen(E2)/progesterone(P4) in endometrial epithelium cell lines(EECs) and endometrial stromal cell line(ESCs),and each circRNA molecule exhibited unique regulation characteristics with respect to E2 and P4.Conclusions: These data provide an endometrium circRNA expression atlas corresponding to the biology of the goat receptive endometrium during embryo implantation.展开更多
Rapid coal-rock identification is one of the key technologies for intelligent and unmanned coal mining.Currently,the existing image recognition algorithms cannot satisfy practical needs in terms of recognition speed a...Rapid coal-rock identification is one of the key technologies for intelligent and unmanned coal mining.Currently,the existing image recognition algorithms cannot satisfy practical needs in terms of recognition speed and accuracy.In view of the evident differences between coal and rock in visual attributes such as color,gloss and texture,the complete local binary pattern(CLBP)image feature descriptor is introduced for coal and rock image recognition.Given that the original algorithm oversimplifies local texture features by ignoring imaging information from higher-order pixels and the concave and convex areas between adjacent sampling points,this paper proposes a higher-order differential median CLBP image feature descriptor to replace the original CLBP center pixel gray with a local gray median,and replace the binary differential with a second-order differential.Meanwhile,for the high dimensionality of CLBP descriptor histogram and feature redundancy,deep learning perceptual field theory is introduced to realize data nonlinear dimensionality reduction and deep feature extraction.With relevant experiments conducted,the following conclusion can be drawn:(1)Compared with that of the original CLBP,the recognition accuracy of the improved CLBP algorithm is greatly improved and finally stabilized above 94.3%under strong noise interference;(2)Compared with that of the original CLBP model,the single image recognition time of the coal rock image recognition model fusing the improved CLBP and the receptive field theory is 0.0035 s,a reduction of 71.0%;compared with the improved CLBP model(without the fusion of receptive field theory),it can shorten the recognition time by 97.0%,but the accuracy rate still maintains more than 98.5%.The method offers a valuable technical reference for the fields of mineral development and deep mining.展开更多
Objective: Inform the public that receptive anal intercourse (RAI) is a key transmission route of the human immunodeficiency virus (HIV) epidemic in the United States. Method: The role of receptive anal intercourse (R...Objective: Inform the public that receptive anal intercourse (RAI) is a key transmission route of the human immunodeficiency virus (HIV) epidemic in the United States. Method: The role of receptive anal intercourse (RAI) in this epidemic will be examined using the following approach: 1) Risk comparison of HIV transmission via RAI to the other major routes of transmission. 2) HIV transmission risks of RAI using some of the present risk reduction techniques. 3) HIV infection via anal intercourse among male youth. 4) HIV infection via anal intercourse among women. Results: Of the major transmission routes of HIV, receptive anal intercourse has the highest transmission risk for acquiring HIV infection. RAI is 2 times the risk of needle-sharing during injection drug use (IDU) and 17 times the risk of receptive vaginal intercourse. The estimated per act probability of acquiring HIV from an infected source by the exposure route of RAI is high in most circumstances: 1) Condoms alone only partially reduce the high risk of RAI. With the addition of pre-exposure prophylaxis (PrEP), the risk is further reduced. 2) When one or both partners are infected with a sexually transmitted disease (STD), even with condom use, the risks are very high. With the addition of PrEP the risks are reduced, but RAI still carries significant risks. 3) With exposure to acute HIV (high viral load) the risks of RAI are very high and remain significant even with condom use and PrEP. Anal intercourse often begins in adolescence;both genders are at risk. Conclusion: Public knowledge of the high transmission risks of receptive anal intercourse may likely result in a downward trend of new HIV infections and contribute to ending the epidemic.展开更多
Using Psychopysical method 126 receptive units in 36 acupoints at human limbs wereclassified.It was shown that the groups of the receptive units were related closely to their peripheralanatomical structures.
The study was performed on neurons with direction selective (DS) receptive fields (RFs) in the primary visual cortex of the cat. Preferred directions (PDs) of these cells to a single light spot and a system of two ide...The study was performed on neurons with direction selective (DS) receptive fields (RFs) in the primary visual cortex of the cat. Preferred directions (PDs) of these cells to a single light spot and a system of two identical light spots moving across the RF with a given angle between them were compared. Directional interactions appeared when the angles between the directions of the two moving spots were 30o or 60o. PD for 56% of the cells coincided with bisectors of these angles. These cells responded to a combination of the two moving stimuli as if only one stimulus moved in the RF in an intermediate direction. This direction coincided with PD of the DS neuron to a single spot. Also, the investigation revealed that DS neurons responded to stimuli moving at such angles as 180o (to preferred and opposite directions simultaneously). In the further experiment we investigated responses of the DS cells in the primary visual cortex of RF. The angle between the directions of the two moving spots was 60o. These cells responded to a combination of the two moving stimuli as if only one stimulus moved in RF in an intermediate direction. The more relative luminance of one of spots in pair was, the closer the intermediate direction approached to the direction of this spot).展开更多
This study attempts to see whether there are any differences between L2 （Second Language） learners＇ receptive and productive knowledge of SP （Semantic Prosody）. SP is defined as the tendency of the use of some wo...This study attempts to see whether there are any differences between L2 （Second Language） learners＇ receptive and productive knowledge of SP （Semantic Prosody）. SP is defined as the tendency of the use of some words to occur in a certain semantic environment. For example, the verb ＂cause＂ is associated with unpleasant things-death, problem and the like. The study is based on a random sampling of subjects （N = 60） drawn from 180 EFL （English as a Foreign Language） learners taking English classes at different language institutes in Khorramabad, Iran. A test of SP as a task of elicitation was constructed, validated and used to measure the learners＇ knowledge of both productive and receptive SP. A matched t-test was used to compare the mean differences between receptive and productive SP measures. The results showed significant difference between EFL learners＇ knowledge of receptive and productive SP, EFL learners perform better in receptive SP measures than in productive ones. Possible imolications of the findings for teaching vocabularv to EFL learners will be discussed.展开更多
Ⅰ.Introduction The training of reading ability is very important in a comprehension lesson of English as asecond language teaching. It refers to many factors, some are inherent in the reading material(its linguistic ...Ⅰ.Introduction The training of reading ability is very important in a comprehension lesson of English as asecond language teaching. It refers to many factors, some are inherent in the reading material(its linguistic difficulties, its contents, its length, its types, etc.); some are present in the展开更多
This paper compared the five different concepts of units of counting vocabulary which are tokens, types, word forms, lemmas and word families, and briefly touched upon how to choose appropriate unit of counting. After...This paper compared the five different concepts of units of counting vocabulary which are tokens, types, word forms, lemmas and word families, and briefly touched upon how to choose appropriate unit of counting. After that, three recognition/receptive vocabulary size tests were introduced.展开更多
The spatial-temporal response properties of some simple neurons in visual pathway arise basically prior to birth. In the absence of visual experience, how do these neurons develop in visual system? Based on Wimbauer n...The spatial-temporal response properties of some simple neurons in visual pathway arise basically prior to birth. In the absence of visual experience, how do these neurons develop in visual system? Based on Wimbauer network with delay, a four-layer feed-forward network model is proposed, which is characterized by modifying the Hebb learning rule through introducing the asymmetric time window of synaptic modification found recently in neurobiology. The model can not only generate by self-organization more diversified spatial-temporal response characteristics of neu-ronal receptive field than earlier models but also provide some explanations for the possible mechanism underlying the development of receptive fields of contrast polarity sensitive neurons found in visual system of vertebrate. Thus the proposed model may be more widely applicable than Linsker model and Wimbauer model.展开更多
The concept of receptive field(RF) is central to sensory neuroscience. Neuronal RF properties have been substantially studied in animals,while those in humans remain nearly unexplored. Here, we measured neuronal RFs w...The concept of receptive field(RF) is central to sensory neuroscience. Neuronal RF properties have been substantially studied in animals,while those in humans remain nearly unexplored. Here, we measured neuronal RFs with intracranial local field potentials(LFPs) and spiking activity in human visual cortex(V1/V2/V3). We recorded LFPs via macro-contacts and discovered that RF sizes estimated from lowfrequency activity(LFA, 0.5–30 Hz) were larger than those estimated from low-gamma activity(LGA, 30–60 Hz) and high-gamma activity(HGA, 60–150 Hz). We then took a rare opportunity to record LFPs and spiking activity via microwires in V1 simultaneously. We found that RF sizes and temporal profiles measured from LGA and HGA closely matched those from spiking activity. In sum, this study reveals that spiking activity of neurons in human visual cortex could be well approximated by LGA and HGA in RF estimation and temporal profile measurement, implying the pivotal functions of LGA and HGA in early visual information processing.展开更多
Spatiotemporal structures of receptive fields (RF) have been studied for simple cells in area 18 of cat by measuring the temporal transfer function (TTF) over different locations (subregions) within the RF. The tempor...Spatiotemporal structures of receptive fields (RF) have been studied for simple cells in area 18 of cat by measuring the temporal transfer function (TTF) over different locations (subregions) within the RF. The temporal characteristics of different subregions differed from each other in the absolute phase shift (APS) to visual stimuli. Two types of relationships can be seen: (i)The APS varied continuously from one subregion to the next; (ii) A 180° phase jump was seen as the stimulus position changed somewhere within the receptive field. Spatiotemporal receptive field profiles have been determined by applying reverse Fourier analysis to responses in the frequency domain. For the continuous type, spatial and temporal characteristics cannot be dissociated (space time inseparable) and the spatiotemporal structure is oriented. On the contrary, the spatial and temporal characteristics for the jumping type can be dissociated (space time separable) and the structure is not oriented in the space time plane. Based on the APSs measured at different subregions, the optimal direction of motion and optimal spatial frequency of neurons can be predicted.展开更多
In order to probe into the self-organizing emergence of simple cell orientation selectivity,we tried to construct a neural network model that consists of LGN neurons and simple cells in visual cortex and obeys the Heb...In order to probe into the self-organizing emergence of simple cell orientation selectivity,we tried to construct a neural network model that consists of LGN neurons and simple cells in visual cortex and obeys the Hebbian learning rule. We investigated the neural coding and representation of simple cells to a natural image by means of this model. The results show that the structures of their receptive fields are determined by the preferred orientation selectivity of simple cells.However, they are also decided by the emergence of self-organization in the unsupervision learning process. This kind of orientation selectivity results from dynamic self-organization based on the interactions between LGN and cortex.展开更多
In this paper,we introduce a novel approach to automatically regulate receptive fields in deep image parsing networks.Unlike previous work which placed much importance on obtaining better receptive fields using manual...In this paper,we introduce a novel approach to automatically regulate receptive fields in deep image parsing networks.Unlike previous work which placed much importance on obtaining better receptive fields using manually selected dilated convolutional kernels,our approach uses two affine transformation layers in the network’s backbone and operates on feature maps.Feature maps are inflated or shrunk by the new layer,thereby changing the receptive fields in the following layers.By use of end-to-end training,the whole framework is data-driven,without laborious manual intervention.The proposed method is generic across datasets and different tasks.We have conducted extensive experiments on both general image parsing tasks,and face parsing tasks as concrete examples,to demonstrate the method’s superior ability to regulate over manual designs.展开更多
Human information processing depends mainly on billions of neurons which constitute a complex neural network,and the information is transmitted in the form of neural spikes.In this paper,we propose a spiking neural ne...Human information processing depends mainly on billions of neurons which constitute a complex neural network,and the information is transmitted in the form of neural spikes.In this paper,we propose a spiking neural network(SNN),named MD-SNN,with three key features:(1) using receptive field to encode spike trains from images;(2) randomly selecting partial spikes as inputs for each neuron to approach the absolute refractory period of the neuron;(3) using groups of neurons to make decisions.We test MD-SNN on the MNIST data set of handwritten digits,and results demonstrate that:(1) Different sizes of receptive fields influence classification results significantly.(2) Considering the neuronal refractory period in the SNN model,increasing the number of neurons in the learning layer could greatly reduce the training time,effectively reduce the probability of over-fitting,and improve the accuracy by 8.77%.(3) Compared with other SNN methods,MD-SNN achieves a better classification;compared with the convolution neural network,MD-SNN maintains flip and rotation invariance(the accuracy can remain at 90.44% on the test set),and it is more suitable for small sample learning(the accuracy can reach 80.15%for 1000 training samples,which is 7.8 times that of CNN).展开更多
Dear Editor,This letter focuses on the fact that small objects with few pixels disappear in feature maps with large receptive fields, as the network deepens, in object detection tasks. Therefore, the detection of dens...Dear Editor,This letter focuses on the fact that small objects with few pixels disappear in feature maps with large receptive fields, as the network deepens, in object detection tasks. Therefore, the detection of dense small objects is challenging.展开更多
With the continuous development of artificial intelligence and machine learning techniques,there have been effective methods supporting the work of dermatologist in the field of skin cancer detection.However,object si...With the continuous development of artificial intelligence and machine learning techniques,there have been effective methods supporting the work of dermatologist in the field of skin cancer detection.However,object significant challenges have been presented in accurately segmenting melanomas in dermoscopic images due to the objects that could interfere human observations,such as bubbles and scales.To address these challenges,we propose a dual U-Net network framework for skin melanoma segmentation.In our proposed architecture,we introduce several innovative components that aim to enhance the performance and capabilities of the traditional U-Net.First,we establish a novel framework that links two simplified U-Nets,enabling more comprehensive information exchange and feature integration throughout the network.Second,after cascading the second U-Net,we introduce a skip connection between the decoder and encoder networks,and incorporate a modified receptive field block(MRFB),which is designed to capture multi-scale spatial information.Third,to further enhance the feature representation capabilities,we add a multi-path convolution block attention module(MCBAM)to the first two layers of the first U-Net encoding,and integrate a new squeeze-and-excitation(SE)mechanism with residual connections in the second U-Net.To illustrate the performance of our proposed model,we conducted comprehensive experiments on widely recognized skin datasets.On the ISIC-2017 dataset,the IoU value of our proposed model increased from 0.6406 to 0.6819 and the Dice coefficient increased from 0.7625 to 0.8023.On the ISIC-2018 dataset,the IoU value of proposed model also improved from 0.7138 to 0.7709,while the Dice coefficient increased from 0.8285 to 0.8665.Furthermore,the generalization experiments conducted on the jaw cyst dataset from Quzhou People’s Hospital further verified the outstanding segmentation performance of the proposed model.These findings collectively affirm the potential of our approach as a valuable tool in supporting clinical decision-making in the field of skin cancer detection,as well as advancing research in medical image analysis.展开更多
Objective:This study aimed to explore the clinical effect of acupuncture therapy for menstruation regu-lation and pregnancy promotion on thin endometrium in the real world.Design:This study is a single-center pragmati...Objective:This study aimed to explore the clinical effect of acupuncture therapy for menstruation regu-lation and pregnancy promotion on thin endometrium in the real world.Design:This study is a single-center pragmatic randomized controlled trial blinded to the statisticians.Using the“blockrand”software package,based on the age(≥35,<35),37 patients were randomized into an intervention group(19 cases)and a control group(18 cases).After reassignment regarding patient preference,21 patients were included in the intervention group and 16 in the control group.Setting:The trial was executed in the Specialty Outpatient Clinic,Acupuncture-Moxibustion Hospital of China Academy of Chinese Medical Sciences,from March 1,2019,to September 30,2020.Participants:The study included 37 patients with thin endometrium and without previous acupuncture treatment.Intervention:The intervention group was administered acupuncture for menstruation regulation and pregnancy promotion and a small-dose of progynova(2 mg daily),while the control group was adminis-tered a large-dose of progynova(4 mg daily).Interventions started from Day 5 of menstruation until the end of ovulation under B-ultrasound monitoring.The intervention lasted for three menstrual cycles.Measurements:Primary outcomes were changes in endometrial thickness between baseline and after intervention completion and the difference between the two groups after intervention.The secondary outcomes were endometrial and subendometrial blood flow,serum estradiol levels,menstrual conditions,and adverse reactions.Results:(1)Comparison of each indicator before and after intervention completion in the two groups:in the intervention group,the differences were significant in endometrial thickness,menstrual score,estra-diol(E2)level in ovulatory period,the pulsatility index(PI)and resistance index(RI)of uterine artery,the ratio of peak systolic velocity to end-diastolic velocity(S/D),the endometrial vascular index(VI),flow index(FI),and vascular flow index(VFI)and volume(P<0.01).In the control group,significant changes were observed in endometrial thickness,menstrual score,and E2 before and after the interven-tion(P<0.05),and no differences were observed in uterine artery PI,RI,S/D and endometrial VI,FI,VFI,and volume(P>0.05).Compared with the control group,the intervention group showed significant differences in endometrial thickness,menstrual score,E2,uterine artery PI,RI,S/D,and endometrial VI,FI,VFI,and volume after intervention(P<0.01).No adverse reactions were reported in the intervention group.In contrast,the control group had two cases of nausea and gastrointestinal discomfort after med-ication,eight cases of breast distention during medication,and one case of breast nodules enlarged by 1 cm after trial completion.展开更多
Background Increased backfat thickness of sows in early gestation is negative to reproductive performance.Endometrial receptivity is an important determinant of reproductive success,but it is unclear whether the effec...Background Increased backfat thickness of sows in early gestation is negative to reproductive performance.Endometrial receptivity is an important determinant of reproductive success,but it is unclear whether the effect of sow backfat thickness on litter size is associated with endometrial receptivity and whether melatonin treatment may have benefits.The present study seeks to answer these questions through in vitro and in vivo investigations.Results Excessive lipid deposition and lower melatonin levels in the uterus are detrimental to endometrial receptivity and embryo implantation in high backfat thickness sows.In cells treated with melatonin,the MT2/PI3K/LIF axis played a role in reducing lipid accumulation in porcine endometrial epithelium cells and improved endometrial receptivity.Furthermore,we found a reduction of lipids in the uterus after eight weeks of intraperitoneal administration of melatonin to HFD mice.Notably,melatonin treatment caused a significant reduction in the deposition of endometrial collagen,an increase in the number of glands,and repair of the pinopode structure,ultimately improving endometrial receptivity,promoting embryo implantation,and increasing the number of litter size of mice.Conclusions Collectively,the finding reveals the harmful effects of high backfat thickness sows on embryo implantation and highlight the role of melatonin and the MT2/PI3K/LIF axis in improving endometrial receptivity by enhancing metabolism and reducing the levels of uterine lipids in obese animals.展开更多
Background Exogenous gonadotropin-controlled ovarian stimulation is the critical step in animal reproductive management,such as pig,sheep,bovine and other species.It helps synchronize ovulation or stimulate multiple o...Background Exogenous gonadotropin-controlled ovarian stimulation is the critical step in animal reproductive management,such as pig,sheep,bovine and other species.It helps synchronize ovulation or stimulate multiple ovu-lations.However,a number of evidence indicated an unexpected decrease in pregnancy outcomes following ovarian stimulation.This study aimed to explore the underlying mechanism of the pregnancy defect and develop a practical rescue strategy.Results Compared with those in the control group,gilts that underwent ovarian stimulation showed a decrease in pregnancy rate,farrowing rate,and total number of piglets born.Stimulated gilts also showed an increase in estra-diol(E_(2))levels.The supraphysiologicalE_(2) level was correlated with the decrease in the number of piglets born.Furthermore,we found that high levels ofE_(2) impair uterine receptivity,as shown by the overproliferation of endo-metrial epithelial cells.In vitro mechanistic studies demonstrated that high levels ofE_(2) hyperactivate FGF-FGFR-ERK signaling cascade in the uterine endometrium,and in turn induces overproliferation of endometrial epithelial cells.Of note,N-acetyl-L-cysteine(NAC)supplementation effectively inhibits ERK hyperphosphorylation and ameliorates endometrial epithelial overproliferation.Importantly,in vivo experiments indicated that dietary NAC supplementa-tion,compared with ovarian stimulation group,improves the uterine receptivity in gilts,and significantly increases the pregnancy rate and total number of piglets born.Conclusions Ovarian stimulation-induced supraphysiological levels ofE_(2) impairs uterine receptivity by hyperactivat-ing FGF-FGFR-ERK signaling cascade,thereby reducing pregnancy rate and litter size.Supplementing NAC to a con-ventional diet for gilts ameliorates hyperactivated ERK signaling and improves uterine receptivity,thus rescuing adverse pregnancy outcomes following ovarian stimulation.展开更多
基金supported by the National Natural Science Foundation of China(Nos.62276204 and 62203343)the Fundamental Research Funds for the Central Universities(No.YJSJ24011)+1 种基金the Natural Science Basic Research Program of Shanxi,China(Nos.2022JM-340 and 2023-JC-QN-0710)the China Postdoctoral Science Foundation(Nos.2020T130494 and 2018M633470).
文摘Drone-based small object detection is of great significance in practical applications such as military actions, disaster rescue, transportation, etc. However, the severe scale differences in objects captured by drones and lack of detail information for small-scale objects make drone-based small object detection a formidable challenge. To address these issues, we first develop a mathematical model to explore how changing receptive fields impacts the polynomial fitting results. Subsequently, based on the obtained conclusions, we propose a simple but effective Hybrid Receptive Field Network (HRFNet), whose modules include Hybrid Feature Augmentation (HFA), Hybrid Feature Pyramid (HFP) and Dual Scale Head (DSH). Specifically, HFA employs parallel dilated convolution kernels of different sizes to extend shallow features with different receptive fields, committed to improving the multi-scale adaptability of the network;HFP enhances the perception of small objects by capturing contextual information across layers, while DSH reconstructs the original prediction head utilizing a set of high-resolution features and ultrahigh-resolution features. In addition, in order to train HRFNet, the corresponding dual-scale loss function is designed. Finally, comprehensive evaluation results on public benchmarks such as VisDrone-DET and TinyPerson demonstrate the robustness of the proposed method. Most impressively, the proposed HRFNet achieves a mAP of 51.0 on VisDrone-DET with 29.3 M parameters, which outperforms the extant state-of-the-art detectors. HRFNet also performs excellently in complex scenarios captured by drones, achieving the best performance on the CS-Drone dataset we built.
基金supported by PhD research startup foundation of Northwest A&F University(00400/Z109021811)National Key Research and Development Program of China(2016YFD0500508)Shaanxi Science and Technology Innovation Project Plan(2015KTCQ03–08)
文摘Background: Recent studies have revealed that noncoding RNAs play important regulatory roles in the formation of endometrial receptivity.Circular RNAs(circRNAs) are a universally expressed noncoding RNA species that have been recently proposed to act as miRNA sponges that directly regulate expression of target genes or parental genes.Results: We used Illumina Solexa technology to analyze the expression profiles of circRNAs in the endometrium from three goats at gestational day 5(pre-receptive endometrium,PE) and three goats at gestational day 15(receptive endometrium,RE).Overall,21,813 circRNAs were identified,of which 5,925 circRNAs were specific to the RE and 9,078 were specific to the PE,which suggested high stage-specificity.Further analysis found 334 differentially expressed circRNAs in the RE compared with PE(P < 0.05).The analysis of the circRNA-miRNA interaction network further supported the idea that circRNAs act as miRNA sponges to regulate gene expression.Moreover,some circRNAs were regulated by estrogen(E2)/progesterone(P4) in endometrial epithelium cell lines(EECs) and endometrial stromal cell line(ESCs),and each circRNA molecule exhibited unique regulation characteristics with respect to E2 and P4.Conclusions: These data provide an endometrium circRNA expression atlas corresponding to the biology of the goat receptive endometrium during embryo implantation.
基金Scientific and technological innovation project of colleges and universities in Shanxi Province,Grant/Award Number:2020L0294Shanxi Province Science Foundation for Youths,Grant/Award Number:201901D211249。
文摘Rapid coal-rock identification is one of the key technologies for intelligent and unmanned coal mining.Currently,the existing image recognition algorithms cannot satisfy practical needs in terms of recognition speed and accuracy.In view of the evident differences between coal and rock in visual attributes such as color,gloss and texture,the complete local binary pattern(CLBP)image feature descriptor is introduced for coal and rock image recognition.Given that the original algorithm oversimplifies local texture features by ignoring imaging information from higher-order pixels and the concave and convex areas between adjacent sampling points,this paper proposes a higher-order differential median CLBP image feature descriptor to replace the original CLBP center pixel gray with a local gray median,and replace the binary differential with a second-order differential.Meanwhile,for the high dimensionality of CLBP descriptor histogram and feature redundancy,deep learning perceptual field theory is introduced to realize data nonlinear dimensionality reduction and deep feature extraction.With relevant experiments conducted,the following conclusion can be drawn:(1)Compared with that of the original CLBP,the recognition accuracy of the improved CLBP algorithm is greatly improved and finally stabilized above 94.3%under strong noise interference;(2)Compared with that of the original CLBP model,the single image recognition time of the coal rock image recognition model fusing the improved CLBP and the receptive field theory is 0.0035 s,a reduction of 71.0%;compared with the improved CLBP model(without the fusion of receptive field theory),it can shorten the recognition time by 97.0%,but the accuracy rate still maintains more than 98.5%.The method offers a valuable technical reference for the fields of mineral development and deep mining.
文摘Objective: Inform the public that receptive anal intercourse (RAI) is a key transmission route of the human immunodeficiency virus (HIV) epidemic in the United States. Method: The role of receptive anal intercourse (RAI) in this epidemic will be examined using the following approach: 1) Risk comparison of HIV transmission via RAI to the other major routes of transmission. 2) HIV transmission risks of RAI using some of the present risk reduction techniques. 3) HIV infection via anal intercourse among male youth. 4) HIV infection via anal intercourse among women. Results: Of the major transmission routes of HIV, receptive anal intercourse has the highest transmission risk for acquiring HIV infection. RAI is 2 times the risk of needle-sharing during injection drug use (IDU) and 17 times the risk of receptive vaginal intercourse. The estimated per act probability of acquiring HIV from an infected source by the exposure route of RAI is high in most circumstances: 1) Condoms alone only partially reduce the high risk of RAI. With the addition of pre-exposure prophylaxis (PrEP), the risk is further reduced. 2) When one or both partners are infected with a sexually transmitted disease (STD), even with condom use, the risks are very high. With the addition of PrEP the risks are reduced, but RAI still carries significant risks. 3) With exposure to acute HIV (high viral load) the risks of RAI are very high and remain significant even with condom use and PrEP. Anal intercourse often begins in adolescence;both genders are at risk. Conclusion: Public knowledge of the high transmission risks of receptive anal intercourse may likely result in a downward trend of new HIV infections and contribute to ending the epidemic.
文摘Using Psychopysical method 126 receptive units in 36 acupoints at human limbs wereclassified.It was shown that the groups of the receptive units were related closely to their peripheralanatomical structures.
文摘The study was performed on neurons with direction selective (DS) receptive fields (RFs) in the primary visual cortex of the cat. Preferred directions (PDs) of these cells to a single light spot and a system of two identical light spots moving across the RF with a given angle between them were compared. Directional interactions appeared when the angles between the directions of the two moving spots were 30o or 60o. PD for 56% of the cells coincided with bisectors of these angles. These cells responded to a combination of the two moving stimuli as if only one stimulus moved in the RF in an intermediate direction. This direction coincided with PD of the DS neuron to a single spot. Also, the investigation revealed that DS neurons responded to stimuli moving at such angles as 180o (to preferred and opposite directions simultaneously). In the further experiment we investigated responses of the DS cells in the primary visual cortex of RF. The angle between the directions of the two moving spots was 60o. These cells responded to a combination of the two moving stimuli as if only one stimulus moved in RF in an intermediate direction. The more relative luminance of one of spots in pair was, the closer the intermediate direction approached to the direction of this spot).
文摘This study attempts to see whether there are any differences between L2 （Second Language） learners＇ receptive and productive knowledge of SP （Semantic Prosody）. SP is defined as the tendency of the use of some words to occur in a certain semantic environment. For example, the verb ＂cause＂ is associated with unpleasant things-death, problem and the like. The study is based on a random sampling of subjects （N = 60） drawn from 180 EFL （English as a Foreign Language） learners taking English classes at different language institutes in Khorramabad, Iran. A test of SP as a task of elicitation was constructed, validated and used to measure the learners＇ knowledge of both productive and receptive SP. A matched t-test was used to compare the mean differences between receptive and productive SP measures. The results showed significant difference between EFL learners＇ knowledge of receptive and productive SP, EFL learners perform better in receptive SP measures than in productive ones. Possible imolications of the findings for teaching vocabularv to EFL learners will be discussed.
文摘Ⅰ.Introduction The training of reading ability is very important in a comprehension lesson of English as asecond language teaching. It refers to many factors, some are inherent in the reading material(its linguistic difficulties, its contents, its length, its types, etc.); some are present in the
文摘This paper compared the five different concepts of units of counting vocabulary which are tokens, types, word forms, lemmas and word families, and briefly touched upon how to choose appropriate unit of counting. After that, three recognition/receptive vocabulary size tests were introduced.
基金Thiswork was supported by the National Natural Science Foundation of China (Grant Nos. 39970185 and 69835002).
文摘The spatial-temporal response properties of some simple neurons in visual pathway arise basically prior to birth. In the absence of visual experience, how do these neurons develop in visual system? Based on Wimbauer network with delay, a four-layer feed-forward network model is proposed, which is characterized by modifying the Hebb learning rule through introducing the asymmetric time window of synaptic modification found recently in neurobiology. The model can not only generate by self-organization more diversified spatial-temporal response characteristics of neu-ronal receptive field than earlier models but also provide some explanations for the possible mechanism underlying the development of receptive fields of contrast polarity sensitive neurons found in visual system of vertebrate. Thus the proposed model may be more widely applicable than Linsker model and Wimbauer model.
基金supported by the National Science and Technology Innovation 2030 Major Program(2022ZD0204802,2022ZD0204804)the National Natural Science Foundation of China(31930053,32171039)Beijing Academy of Artificial Intelligence(BAAI)。
文摘The concept of receptive field(RF) is central to sensory neuroscience. Neuronal RF properties have been substantially studied in animals,while those in humans remain nearly unexplored. Here, we measured neuronal RFs with intracranial local field potentials(LFPs) and spiking activity in human visual cortex(V1/V2/V3). We recorded LFPs via macro-contacts and discovered that RF sizes estimated from lowfrequency activity(LFA, 0.5–30 Hz) were larger than those estimated from low-gamma activity(LGA, 30–60 Hz) and high-gamma activity(HGA, 60–150 Hz). We then took a rare opportunity to record LFPs and spiking activity via microwires in V1 simultaneously. We found that RF sizes and temporal profiles measured from LGA and HGA closely matched those from spiking activity. In sum, this study reveals that spiking activity of neurons in human visual cortex could be well approximated by LGA and HGA in RF estimation and temporal profile measurement, implying the pivotal functions of LGA and HGA in early visual information processing.
文摘Spatiotemporal structures of receptive fields (RF) have been studied for simple cells in area 18 of cat by measuring the temporal transfer function (TTF) over different locations (subregions) within the RF. The temporal characteristics of different subregions differed from each other in the absolute phase shift (APS) to visual stimuli. Two types of relationships can be seen: (i)The APS varied continuously from one subregion to the next; (ii) A 180° phase jump was seen as the stimulus position changed somewhere within the receptive field. Spatiotemporal receptive field profiles have been determined by applying reverse Fourier analysis to responses in the frequency domain. For the continuous type, spatial and temporal characteristics cannot be dissociated (space time inseparable) and the spatiotemporal structure is oriented. On the contrary, the spatial and temporal characteristics for the jumping type can be dissociated (space time separable) and the structure is not oriented in the space time plane. Based on the APSs measured at different subregions, the optimal direction of motion and optimal spatial frequency of neurons can be predicted.
基金the National Natural Science Foundation of China (Grant Nos. 39893340-06, 69835020, 39670186).
文摘In order to probe into the self-organizing emergence of simple cell orientation selectivity,we tried to construct a neural network model that consists of LGN neurons and simple cells in visual cortex and obeys the Hebbian learning rule. We investigated the neural coding and representation of simple cells to a natural image by means of this model. The results show that the structures of their receptive fields are determined by the preferred orientation selectivity of simple cells.However, they are also decided by the emergence of self-organization in the unsupervision learning process. This kind of orientation selectivity results from dynamic self-organization based on the interactions between LGN and cortex.
基金supported by the National Natural Science Foundation of China (Nos.U1536203,61572493)the Cutting Edge Technology Research Program of the Institute of Information Engineering,CAS (No.Y7Z0241102)+1 种基金the Key Laboratory of Intelligent Perception and Systems for High-Dimensional Information of the Ministry of Education (No.Y6Z0021102)Nanjing University of Science and Technology (No.JYB201702)
文摘In this paper,we introduce a novel approach to automatically regulate receptive fields in deep image parsing networks.Unlike previous work which placed much importance on obtaining better receptive fields using manually selected dilated convolutional kernels,our approach uses two affine transformation layers in the network’s backbone and operates on feature maps.Feature maps are inflated or shrunk by the new layer,thereby changing the receptive fields in the following layers.By use of end-to-end training,the whole framework is data-driven,without laborious manual intervention.The proposed method is generic across datasets and different tasks.We have conducted extensive experiments on both general image parsing tasks,and face parsing tasks as concrete examples,to demonstrate the method’s superior ability to regulate over manual designs.
基金supported by the National Natural Science Foundation of China(Nos.61773312,61773307,and L1522023)the China Postdoctoral Science Foundation(No.2016M590949)the National Basic Research Program(973)of China(No.2015CB351703)
文摘Human information processing depends mainly on billions of neurons which constitute a complex neural network,and the information is transmitted in the form of neural spikes.In this paper,we propose a spiking neural network(SNN),named MD-SNN,with three key features:(1) using receptive field to encode spike trains from images;(2) randomly selecting partial spikes as inputs for each neuron to approach the absolute refractory period of the neuron;(3) using groups of neurons to make decisions.We test MD-SNN on the MNIST data set of handwritten digits,and results demonstrate that:(1) Different sizes of receptive fields influence classification results significantly.(2) Considering the neuronal refractory period in the SNN model,increasing the number of neurons in the learning layer could greatly reduce the training time,effectively reduce the probability of over-fitting,and improve the accuracy by 8.77%.(3) Compared with other SNN methods,MD-SNN achieves a better classification;compared with the convolution neural network,MD-SNN maintains flip and rotation invariance(the accuracy can remain at 90.44% on the test set),and it is more suitable for small sample learning(the accuracy can reach 80.15%for 1000 training samples,which is 7.8 times that of CNN).
基金supported in part by the National Science Foundation of China(52371372)the Project of Science and Technology Commission of Shanghai Municipality,China(22JC1401400,21190780300)the 111 Project,China(D18003)
文摘Dear Editor,This letter focuses on the fact that small objects with few pixels disappear in feature maps with large receptive fields, as the network deepens, in object detection tasks. Therefore, the detection of dense small objects is challenging.
基金funded by Zhejiang Basic Public Welfare Research Project,grant number LZY24E060001supported by Guangzhou Development Zone Science and Technology(2021GH10,2020GH10,2023GH02)+1 种基金the University of Macao(MYRG2022-00271-FST)the Science and Technology Development Fund(FDCT)of Macao(0032/2022/A).
文摘With the continuous development of artificial intelligence and machine learning techniques,there have been effective methods supporting the work of dermatologist in the field of skin cancer detection.However,object significant challenges have been presented in accurately segmenting melanomas in dermoscopic images due to the objects that could interfere human observations,such as bubbles and scales.To address these challenges,we propose a dual U-Net network framework for skin melanoma segmentation.In our proposed architecture,we introduce several innovative components that aim to enhance the performance and capabilities of the traditional U-Net.First,we establish a novel framework that links two simplified U-Nets,enabling more comprehensive information exchange and feature integration throughout the network.Second,after cascading the second U-Net,we introduce a skip connection between the decoder and encoder networks,and incorporate a modified receptive field block(MRFB),which is designed to capture multi-scale spatial information.Third,to further enhance the feature representation capabilities,we add a multi-path convolution block attention module(MCBAM)to the first two layers of the first U-Net encoding,and integrate a new squeeze-and-excitation(SE)mechanism with residual connections in the second U-Net.To illustrate the performance of our proposed model,we conducted comprehensive experiments on widely recognized skin datasets.On the ISIC-2017 dataset,the IoU value of our proposed model increased from 0.6406 to 0.6819 and the Dice coefficient increased from 0.7625 to 0.8023.On the ISIC-2018 dataset,the IoU value of proposed model also improved from 0.7138 to 0.7709,while the Dice coefficient increased from 0.8285 to 0.8665.Furthermore,the generalization experiments conducted on the jaw cyst dataset from Quzhou People’s Hospital further verified the outstanding segmentation performance of the proposed model.These findings collectively affirm the potential of our approach as a valuable tool in supporting clinical decision-making in the field of skin cancer detection,as well as advancing research in medical image analysis.
基金Supported by Special Funds for Basic Scientific Research of Central Public Welfare Research Institutes:201814006。
文摘Objective:This study aimed to explore the clinical effect of acupuncture therapy for menstruation regu-lation and pregnancy promotion on thin endometrium in the real world.Design:This study is a single-center pragmatic randomized controlled trial blinded to the statisticians.Using the“blockrand”software package,based on the age(≥35,<35),37 patients were randomized into an intervention group(19 cases)and a control group(18 cases).After reassignment regarding patient preference,21 patients were included in the intervention group and 16 in the control group.Setting:The trial was executed in the Specialty Outpatient Clinic,Acupuncture-Moxibustion Hospital of China Academy of Chinese Medical Sciences,from March 1,2019,to September 30,2020.Participants:The study included 37 patients with thin endometrium and without previous acupuncture treatment.Intervention:The intervention group was administered acupuncture for menstruation regulation and pregnancy promotion and a small-dose of progynova(2 mg daily),while the control group was adminis-tered a large-dose of progynova(4 mg daily).Interventions started from Day 5 of menstruation until the end of ovulation under B-ultrasound monitoring.The intervention lasted for three menstrual cycles.Measurements:Primary outcomes were changes in endometrial thickness between baseline and after intervention completion and the difference between the two groups after intervention.The secondary outcomes were endometrial and subendometrial blood flow,serum estradiol levels,menstrual conditions,and adverse reactions.Results:(1)Comparison of each indicator before and after intervention completion in the two groups:in the intervention group,the differences were significant in endometrial thickness,menstrual score,estra-diol(E2)level in ovulatory period,the pulsatility index(PI)and resistance index(RI)of uterine artery,the ratio of peak systolic velocity to end-diastolic velocity(S/D),the endometrial vascular index(VI),flow index(FI),and vascular flow index(VFI)and volume(P<0.01).In the control group,significant changes were observed in endometrial thickness,menstrual score,and E2 before and after the interven-tion(P<0.05),and no differences were observed in uterine artery PI,RI,S/D and endometrial VI,FI,VFI,and volume(P>0.05).Compared with the control group,the intervention group showed significant differences in endometrial thickness,menstrual score,E2,uterine artery PI,RI,S/D,and endometrial VI,FI,VFI,and volume after intervention(P<0.01).No adverse reactions were reported in the intervention group.In contrast,the control group had two cases of nausea and gastrointestinal discomfort after med-ication,eight cases of breast distention during medication,and one case of breast nodules enlarged by 1 cm after trial completion.
基金supported by the China Agriculture Research System(CARS-35-PIG)the National Natural Science Foundation of China(32272847,U22A20516)+1 种基金the National Key Research and Development Program of China(No.2021YFF1000602)the Key Research and Development Program of Shaanxi Province(No.2022ZDLNY01–04)。
文摘Background Increased backfat thickness of sows in early gestation is negative to reproductive performance.Endometrial receptivity is an important determinant of reproductive success,but it is unclear whether the effect of sow backfat thickness on litter size is associated with endometrial receptivity and whether melatonin treatment may have benefits.The present study seeks to answer these questions through in vitro and in vivo investigations.Results Excessive lipid deposition and lower melatonin levels in the uterus are detrimental to endometrial receptivity and embryo implantation in high backfat thickness sows.In cells treated with melatonin,the MT2/PI3K/LIF axis played a role in reducing lipid accumulation in porcine endometrial epithelium cells and improved endometrial receptivity.Furthermore,we found a reduction of lipids in the uterus after eight weeks of intraperitoneal administration of melatonin to HFD mice.Notably,melatonin treatment caused a significant reduction in the deposition of endometrial collagen,an increase in the number of glands,and repair of the pinopode structure,ultimately improving endometrial receptivity,promoting embryo implantation,and increasing the number of litter size of mice.Conclusions Collectively,the finding reveals the harmful effects of high backfat thickness sows on embryo implantation and highlight the role of melatonin and the MT2/PI3K/LIF axis in improving endometrial receptivity by enhancing metabolism and reducing the levels of uterine lipids in obese animals.
基金National Natural Science Foundation of China(31930103)National Center of Technology Innovation for Pigs(NCTIP-XD/B03)+2 种基金Ningbo Major Science and Technology Project(2021Z112)National Key R&D Program(2022YFD1300303)Beijing Innovation Consortium of Livestock Research System BAIC05-2024.
文摘Background Exogenous gonadotropin-controlled ovarian stimulation is the critical step in animal reproductive management,such as pig,sheep,bovine and other species.It helps synchronize ovulation or stimulate multiple ovu-lations.However,a number of evidence indicated an unexpected decrease in pregnancy outcomes following ovarian stimulation.This study aimed to explore the underlying mechanism of the pregnancy defect and develop a practical rescue strategy.Results Compared with those in the control group,gilts that underwent ovarian stimulation showed a decrease in pregnancy rate,farrowing rate,and total number of piglets born.Stimulated gilts also showed an increase in estra-diol(E_(2))levels.The supraphysiologicalE_(2) level was correlated with the decrease in the number of piglets born.Furthermore,we found that high levels ofE_(2) impair uterine receptivity,as shown by the overproliferation of endo-metrial epithelial cells.In vitro mechanistic studies demonstrated that high levels ofE_(2) hyperactivate FGF-FGFR-ERK signaling cascade in the uterine endometrium,and in turn induces overproliferation of endometrial epithelial cells.Of note,N-acetyl-L-cysteine(NAC)supplementation effectively inhibits ERK hyperphosphorylation and ameliorates endometrial epithelial overproliferation.Importantly,in vivo experiments indicated that dietary NAC supplementa-tion,compared with ovarian stimulation group,improves the uterine receptivity in gilts,and significantly increases the pregnancy rate and total number of piglets born.Conclusions Ovarian stimulation-induced supraphysiological levels ofE_(2) impairs uterine receptivity by hyperactivat-ing FGF-FGFR-ERK signaling cascade,thereby reducing pregnancy rate and litter size.Supplementing NAC to a con-ventional diet for gilts ameliorates hyperactivated ERK signaling and improves uterine receptivity,thus rescuing adverse pregnancy outcomes following ovarian stimulation.
