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Purpose: Automatic segmentation of prostate magnetic resonance (MR) images is crucial for the diagnosis, evaluation, and prognosis of prostate diseases (including prostate cancer). In recent years, the mainstream segmentation method for the prostate has been converted to convolutional neural networks. However, owing to the complexity of the tissue structure in MR images and the limitations of existing methods in spatial context modeling, the segmentation performance should be improved further. Methods: In this study, we proposed a novel 3D pyramid pool Unet that benefits from the pyramid pooling structure embedded in the skip connection (SC) and the deep supervision (DS) in the up-sampling of the 3D Unet. The parallel SC of the conventional 3D Unet network causes low-resolution information to be sent to the feature map repeatedly, resulting in blurred image features. To overcome the shortcomings of the conventional 3D Unet, we merge each decoder layer with the feature map of the same scale as the encoder and the smaller scale feature map of the pyramid pooling encoder. This SC combines the low-level details and high-level semantics at two different levels of feature maps. In addition, pyramid pooling performs multifaceted feature extraction on each image behind the convolutional layer, and DS learns hierarchical representations from comprehensive aggregated feature maps, which can improve the accuracy of the task. Results: Experiments on 3D prostate MR images of 78 patients demonstrated that our results were highly correlated with expert manual segmentation. The average relative volume difference and Dice similarity coefficient of the prostate volume area were 2.32% and 91.03%, respectively. Conclusion: Quantitative experiments demonstrate that, compared with other methods, the results of our method are highly consistent with the expert manual segmentation. [ABSTRACT FROM AUTHOR]

Hainan Province is in a tropical area of China and previously experienced serious P. falciparum and P. vivax malaria epidemics. After nearly 70 consecutive years of malaria prevention and control, malaria in Hainan has gradually been eliminated. To achieve the elimination of malaria, Hainan enacted six stages: investigative research and pilot prevention and control, large-scale antimalaria measures, adjustment of strategies for prevention and control, joint prevention and control measures, global funding of routine malaria control, and malaria elimination. Different strategies for malaria control were adopted at different stages. Malaria was most prevalent in the mountainous areas of central and southern Hainan, which contain a high-risk population (the forest goers) and two highly effective malaria vectors (An. dirus and An. minimus). Forest goers have been a high-risk population for malaria in Hainan since their identification in the 1990s. This paper summarizes malaria monitoring in forest goers and the response of forest goers to malaria control and elimination, distilling specific malaria control and elimination measures via case studies in Hainan Province. Two case studies in the malaria control stage demonstrated different measures for outbreaks and sporadic cases in forest goers. In view of the malaria outbreak in Sanya during the elimination stage, three-layered strategies (TLSs) were implemented to control outbreaks and improve control measures. Moreover, this paper also illustrates specific management measures to prevent malaria retransmission from sporadic imported malaria cases during the elimination phase. Hainan finally eliminated malaria in 2020. However, the risk of malaria retransmission is still high due to the prevalence of effective malaria vectors in Hainan, and forest goers are still a high-risk population for malaria retransmission. [ABSTRACT FROM AUTHOR]

This paper reports on a new secondary instability phenomenon of parametric sloshing. Faraday first experimentally discovered the (1/2 sub-harmonic) parametric sloshing phenomenon in 1831. The parametric instability starts from a small disturbance on the free fluid surface, and then the sloshing amplitude of fluid increases exponentially and finally reaches a steady-state limit cycle oscillation. This parametric instability is called the first (linear) instability. The parametric sloshing experiment of this study discovers that in the case of the parametric excitation unchanged, the free fluid surface that is in a limit cycle oscillation might undergo a secondary instability. Under this circumstance, the sloshing amplitude of free surface increases sharply. The consequence is catastrophic - the fluid is splashed out of the tank. During the secondary instability, the sloshing mode (or energy) is transferred from the third mode to the first mode. The secondary instability, which is different from the first instability, is a nonlinear unstable process. The mechanism of the secondary instability is needed a further study. [ABSTRACT FROM AUTHOR]

The aim of the present study was to explore the associations of genetic variants in the ADAM33 and TGF-β1 genes with the risk of childhood asthma. A total of 299 asthmatic children and 311 healthy controls were recruited in the hospital-based case-control study. The asthmatic subjects were further divided into mild and severe groups according to disease severity. Single-nucleotide polymorphisms (SNP) at ADAM33 V4, T2, S2 and T1, and TGF-β1 C-509T and T869C were selected and detected with PCR-RFLP. The associations of the SNPs with asthma risk and severity were analyzed. The associations between the haplotypes of ADAM33 and TGF-β1 were also evaluated. Compared with the GG genotype, the GC and CC genotypes at V4 were associated with an increased asthma risk in children and the ORs were 2.92 and 10.56, respectively. Compared with the CC genotype, the CT/TT genotype at C-509T was associated with an increased asthma risk and the OR was 2.26. Subsequent to stratification by asthma severity, compared with the V4 GG genotype, it was found that the CG and CC genotypes were associated with a mild asthma risk and the ORs were 3.00 and 5.99, respectively. The SNP at C-509T (CT/TT vs. CC) was associated with mild asthma (OR = 2.34), whereas a marginally significant association was detected between the SNP (CT/ TT vs. CC) and severe asthma risk (OR = 2.19). The haplotype analysis revealed that, compared with the GGCA haplotype of ADAM33, significant associations of the haplotypes of CGCG, CGGA, GACA, GACG and GAGA with asthma risk were observed, and the ORs were 31.12, 12.24, 4.73, 30.85 and 4.83, respectively. No significant association was detected between the TGF-β1 haplotypes and asthma risk. The genetic variants at V4 and C-509T had the potential to modify the childhood asthma risk and the associations showed no notable difference with the disease severity. Thus, ADAM33 haplotypes provided more useful information in the prediction of asthma risk. [ABSTRACT FROM AUTHOR]

An approximate analytical solution of sloshing frequencies for a liquid in the various shape aqueducts is formulated by using the Ritz method. The present approximate method is, respectively, applied to find the sloshing frequencies of the liquid in rectangular, trapezoid, oval, circular, U-shaped tanks (aqueducts), and various shape tuned liquid dampers (TLD). The first three antisymmetric and symmetric frequencies by the present approach are within 5% accuracy compared to the other analytical, numerical, and experimental values. The approximate solutions of this paper for the various shape aqueducts are acceptable to the engineering applications. [ABSTRACT FROM AUTHOR]

Quantitative studies on the uptake of nanoparticles into biological systems should consider simultaneous agglomeration, sedimentation, and diffusion at physiologically relevant concentrations to assess the corresponding risks of nanomaterials to human health. In this paper, the transport and uptake of industrially important cerium oxide nanoparticles, into human lung fibroblasts is measured in vitro after exposing thoroughly characterized particle suspensions to a fibroblast cell culture for particles of four separate size fractions and concentrations ranging from 100 ng g-1 to 100 μg g-1 of fluid (100 ppb to 100 ppm). The unexpected findings at such low but physiologically relevant concentrations reveal a strong dependence of the amount of incorporated ceria on particle size, while nanoparticle number density or total particle surface area are of minor importance. These findings can be explained on the basis of a purely physical model. The rapid formation of agglomerates in the liquid is strongly favored for small particles due to a high number density while larger ones stay mainly unagglomerated. Diffusion (size fraction 25-50 nm) or sedimentation (size fraction 250-500 nm) limits the transport of nanoparticles to the fibroblast cells. The biological uptake processes on the surface of the cell are faster than the physical transport to the cell at such low concentrations. Comparison of the colloid stability of a series of oxide nanoparticles reveals that untreated oxide suspensions rapidly agglomerate in biological fluids and allows the conclusion that the presented transport and uptake kinetics at low concentrations may be extended to other industrially relevant materials. [ABSTRACT FROM AUTHOR]

Niviventer confucianus sacer Thomas, 1908, which has been regarded as a subspecies of N. confucianus, was found to be a distinct species from N. confucianus based on molecular, karyotyping, and morphological characteristics in this study. Niviventer c. sacer was found to belong to a distinct phylogenetic clade in phylogenetic tree constructed using the mitochondrial gene Cytb, it clustered with N. bukit (Bonhote, 1903) from Vietnam and N. confucianus (Milne-Edwards, 1871) from Yunnan, but showed a distant relationship with N. confucianus from adjacent areas. The genetic distance between N. c. sacer and N. confucianus was more than 5.8%, reaching the level of interspecific differentiation. The species delimitation indicates that N. c. sacer is a monophyletic group. The karyotype of N. c. sacer (FN = 55, 8m+4st+32t+X(sm)Y(t)) differed from that of N. confucianus (FN = 59, 6m+4sm+2st+32t+X(sm)Y(t)). In terms of morphological features, the length of incisive foramen (LIF) and length of auditory bulla (LAB) of N. c. sacer is significantly larger than that of N. confucianus and N. bukit (P < 0.05) and the proportion of white tail tip to total tail length is significantly longer at N. c. sacer (= 1/3) than that at N. confucianus (= 1/3). Therefore, integrated analysis confirmed that N. c. sacer is a distinct species of genus Niviventer rather than a subspecies of N. confucianus or N. bukit, namely N. sacer, which is only distributed in Shandong. [ABSTRACT FROM AUTHOR]

The Taiwanese gray shrew (Crocidura tanakae) and Asian gray shrew (C. attenuata) are so similar in size and morphology that the taxonomic status of the former has changed several times since its description; C. tanakae has also been regarded as an endemic species of Taiwan Island. In recent years, molecular identification has led to several reports of C. tanakae being distributed in the mainland of China. In this study, we determine the geographical distribution of C. attenuata and C. tanakae based on more than one hundred specimens collected during 2000 to 2018 over a wide area covering the traditional ranges of the two species in the mainland of China, and show a substantial revision of their distributions. Among 110 individuals, 33 C. attenuata and 77 C. tanakae were identified by Cytb gene and morphologies. Our results show, (1) C. attenuata and C. tanakae are distributed sympatrically in the mainland of China; (2) contrary to the previous reports, the distribution range of C. attenuata is restricted and much smaller than that of C. tanakae in the mainland of China; (3) Hainan Island, like Taiwan Island, is inhabited by C. tanakae only according to the present data. [ABSTRACT FROM AUTHOR]

Background/Aims: The roots of Averrhoa carambola L. (Oxalidaceae) have long been used as a traditional Chinese medicine for the treatment of headaches, vomiting, coughing and hangovers. 2-dodecyl-6-methoxycyclohexa-2, 5-1, 4-dione (DMDD) has been isolated from A. carambola L. roots, and this study was carried out to investigate the potential beneficial effects of DMDD on neuron apoptosis and memory deficits in Alzheimer's disease. Methods: The effects of a DMDD on learning and memory in APP/PS1 transgenic AD mice in vivo were investigated via Morris water maze and Y-type electric maze tests. In vitro, Cell viability was assessed by CCK-8. Apoptosis was assessed by Annexin V-FITC/PI flow cytometry assay, and transmission electron microscopy assay. Relative quantitative real-time PCR and Western blot were used to determine the expressions of genes and proteins. Results: The spatial learning and memory deficit, fear memory deficit, as well as apoptosis and loss of neuron in hippocampal area of APP/PS1 mice were reversed by DMDD in APP/PS1 transgenic AD mice. DMDD protected against the Aβ1-42-induced apoptosis, loss of mitochondria membrane potential, induction of pro-apoptotic Bcl-2 family protein Bax, reduction of anti-apoptotic Bcl-2 family proteins Bcl-2, and activation of Caspase-3, and -9 in PC-12 cells. The Bcl-2/Bax ratio was also increased in DMDD-pretreated PC-12 cells in vitro and APP/PS1 mice in vivo. Conclusion: DMDD has potential benefit on treating learning and memory deficit in APP/PS1 transgenic AD mice, and its effects may be associated with reversing the apoptosis of neuron via inhibiting Bax/Bcl-2 mediated mitochondrial membrane potential loss. [ABSTRACT FROM AUTHOR]

Myotis indochinensis, a recently described species from Vietnam, was previously confused with Myotis montivagus and Myotis annectans; however, it could be distinguished from these species by its larger external, cranial measurements and well-developed sagittal and lambdoid crests. In 2012 and 2015, one and three mediumsized Myotis bats were collected in Nanling National Nature Reserve, Guangdong Province and Jiulianshan National Nature Reserve, Jiangxi Province, China, respectively. Based on their morphological characteristics and phylogenetic inference using complete cytochrome b gene and partial cytochrome oxidase subunit I gene, they were identified as M. indochinensis, representing the first records of the species in China. [ABSTRACT FROM AUTHOR]

Circulating ultrasonic-assisted extraction (CUAE) was developed as a novel method for extraction of medicinal herbs, and the method was validated. In addition, the novel hyphenated technique comprising CUAE coupled with countercurrent chromatography (CCC) and centrifugal partition chromatography (CPC) was developed and applied to the continuous extraction and online isolation of chemical constituents from Ligusticum chuanxiong Hort. The optimum extraction parameters, including the extraction time of 30 min, extraction temperature of 45 °C, ultrasound power of 300 W, and the liquid-solid ratio of 10 mL/g were determined by response surface methodology. Furthermore, a schematic and the mechanism of online CUAE coupled with CCC and CPC were presented. Three lactones, levistolide A (52.2 mg), Z-ligustilide (48.3 mg), and wallichilide (118.2 mg), with respective purities of 95.8, 96.7, and 96.2%, were obtained from 500 g of the L. chuanxiong raw material using CUAE/CCC. In contrast, senkyunolide A (26.2 mg), levistolide A (34.2 mg), and wallichilide (95.1 mg), with respective purities of 96.2, 95.3, and 96.1%, were obtained from 500 g of the L. chuanxiong raw material by using CUAE/CPC employing the two-phase solvent system comprising n-hexane-ethyl acetate-methanol-water in a volume ratio of 4:3:4:2 (v/v). Compared with reference extraction methods, scientific and systematic extraction and isolation of natural products was achieved with the instrumental setup, and this system has great prospects for industrial application, where the combined use of CCC and CPC can enhance the separation efficiency. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented about Hendra and Nipah viruses in bats in China.