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Purpose: Deep learning is an emerging reconstruction method for positron emission tomography (PET), which can tackle complex PET corrections in an integrated procedure. This paper optimizes the direct PET reconstruction from sinogram on a long axial field of view (LAFOV) PET. Methods: This paper proposes a novel deep learning architecture to reduce the biases during direct reconstruction from sinograms to images. This architecture is based on an encoder-decoder network, where the perceptual loss is used with pre-trained convolutional layers. It is trained and tested on data of 80 patients acquired from recent Siemens Biograph Vision Quadra long axial FOV (LAFOV) PET/CT. The patients are randomly split into a training dataset of 60 patients, a validation dataset of 10 patients, and a test dataset of 10 patients. The 3D sinograms are converted into 2D sinogram slices and used as input to the network. In addition, the vendor reconstructed images are considered as ground truths. Finally, the proposed method is compared with DeepPET, a benchmark deep learning method for PET reconstruction. Results: Compared with DeepPET, the proposed network significantly reduces the root-mean-squared error (NRMSE) from 0.63 to 0.6 (p < 0.01) and increases the structural similarity index (SSIM) and peak signal-to-noise ratio (PSNR) from 0.93 to 0.95 (p < 0.01) and from 82.02 to 82.36 (p < 0.01), respectively. The reconstruction time is approximately 10 s per patient, which is shortened by 23 times compared with the conventional method. The errors of mean standardized uptake values (SUVmean) for lesions between ground truth and the predicted result are reduced from 33.5 to 18.7% (p = 0.03). In addition, the error of max SUV is reduced from 32.7 to 21.8% (p = 0.02). Conclusion: The results demonstrate the feasibility of using deep learning to reconstruct images with acceptable image quality and short reconstruction time. It is shown that the proposed method can improve the quality of deep learning-based reconstructed images without additional CT images for attenuation and scattering corrections. This study demonstrated the feasibility of deep learning to rapidly reconstruct images without additional CT images for complex corrections from actual clinical measurements on LAFOV PET. Despite improving the current development, AI-based reconstruction does not work appropriately for untrained scenarios due to limited extrapolation capability and cannot completely replace conventional reconstruction currently. [ABSTRACT FROM AUTHOR]

The article discusses benefits of alloparental care in Great Tits (Parus major). It mentions efforts at a nest during an ongoing breeding season increase the parents' future survival and reproductive success rates; and also mentions Alloparents may get the benefit of acquiring practice before their own breeding and help increase their success in the next breeding season.

Background: Shidu parents refer to the couple who have lost their only child and have not given birth or adopted another child in China. The number of Shidu parents is increasing annually. The aim of this research was to examine the mediating role of anxiety and the moderating role of social support between perceived stress and prolonged grief disorder (PGD) among Chinese Shidu parents. Methods: A cross-sectional study was carried out with 505 participants who completed a questionnaire including the Prolonged Grief Questionnair-3 (PG-13), the Perceived Stress Scale-10 (PSS-10), the Self-Rating Anxiety Scale (SAS) and the Duke-UNC Functional Social Support Questionnaire (FSSQ). SPSS PROCESS macro was employed to examine the mediating role of anxiety and the moderating role of social support. Results: The mediation analysis showed anxiety partially mediated the link between perceived stress and PGD, and the proportion of mediation of anxiety was 39.22%. The moderated mediation analysis revealed the second stage of mediating effects of anxiety on the link between perceived stress and PGD was moderated by social support. Specifically, compared with Shidu parents with higher social support, the association between anxiety and PGD was closer for those with lower social support. Conclusions: The moderated mediation model can broaden our understanding of how and when perceived stress, anxiety and social support work together to affect PGD. The interventions aimed at improving mental health of Chinese Shidu parents need to work on reducing stress and enhancing social support. [ABSTRACT FROM AUTHOR]

A creatively designed novel two-step enhancement technique is presented in which B vitamin molecules are dynamically adsorbed onto the surface of silver nanoparticles by sodium borohydride, followed by local plasmon resonance in the presence of cations (calcium ions), ultimately achieving synergistic chemical and physical enhancement on the same molecule and constructing a "surface hot spots" two-step enhancement platform for vitamin detection. The Raman signal of the promoted vitamin molecule is enhanced by nine orders of magnitude. In a subsequent study it was observed that the vitamin B2 molecules were in a near-vertical image on the surface of the silver nanoparticles, which may also contribute to the Raman signal enhancement. Combined with deep learning techniques, the method has been successfully applied to the detection of B vitamins in body fluids. As an accurate, rapid, reproducible, non-invasive, and versatile assay platform, it holds great promise for the intelligent identification of trace B molecules in food, pharmaceuticals, and the human body. [ABSTRACT FROM AUTHOR]

The spatial distribution and breeding behavior of neighboring birds (conspecific and heterospecific) may influence reproduction and the effects differ across species. In this study, we investigated intra- and inter-specific spatial distribution of breeding via artificial nestboxes and examined whether overlap with neighbors affected reproductive success of the focal breeding pair. Regarding spatial distribution, Varied Tits (Sittiparus varius) and Cinereous Tits (Parus cinereus) showed similar pattern: distances of nestboxes containing conspecific tits were greater than those with heterospecific ones. In terms of breeding behavior, reproductive success was not significantly related to the distance from their neighbor's nest. The reproductive success of Varied Tits was significantly related to that of their neighbors, while in Cinereous Tits, no strong link was found to any recorded reproductive behavior of the neighbors. These findings explain spatial variation in nest site selection of Varied Tits and Cinereous Tits. Reproductive success rate of Varied Tits is affected by that of the neighbors while that of Cinereous Tits is not. The results highlight that there are differences in reproductive outcome among related species and offer suggestions on the use of artificial nestboxes in experiment and conservation programs. [ABSTRACT FROM AUTHOR]