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1.
Skin Res Technol ; 30(4): e13679, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38616503

RESUMO

BACKGROUND: Injectable filler, a nonsurgical beauty method, has gained popularity in rejuvenating sagging skin. In this study, polydioxanone (PDO) was utilized as the main component of the ULTRACOL200 filler that helps stimulate collagenesis and provide skin radiant effects. The study aimed to evaluate and compare the effectiveness of ULTRACOL200 with other commercialized products in visually improving dermatological problems. METHODS: Herein, 31 participants aged between 20 and 59 years were enrolled in the study. 1 mL of the testing product, as well as the quantity for the compared groups was injected into each participants face side individually. Subsequently, skin texture and sunken volume of skin were measured using ANTERA 3D CS imaging technology at three periods: before the application, 4 weeks after the initial application, and 4 weeks after the 2nd application of ULTRACOL200. RESULTS: The final results of skin texture and wrinkle volume evaluation consistently demonstrated significant enhancement. Consequently, subjective questionnaires were provided to the participants to evaluate the efficacy of the testing product, illustrating satisfactory responses after the twice applications. CONCLUSION: The investigation has contributed substantially to the comprehension of a PDO-based filler (ULTRACOL200) for skin enhancement and provided profound insight for future clinical trials.


Assuntos
Sulco Nasogeniano , Transplante de Pele , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Pele/diagnóstico por imagem , Imageamento Tridimensional , Tecnologia
2.
IEEE J Biomed Health Inform ; 28(5): 2854-2865, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38427554

RESUMO

Automated segmentation of liver tumors in CT scans is pivotal for diagnosing and treating liver cancer, offering a valuable alternative to labor-intensive manual processes and ensuring the provision of accurate and reliable clinical assessment. However, the inherent variability of liver tumors, coupled with the challenges posed by blurred boundaries in imaging characteristics, presents a substantial obstacle to achieving their precise segmentation. In this paper, we propose a novel dual-branch liver tumor segmentation model, SBCNet, to address these challenges effectively. Specifically, our proposed method introduces a contextual encoding module, which enables a better identification of tumor variability using an advanced multi-scale adaptive kernel. Moreover, a boundary enhancement module is designed for the counterpart branch to enhance the perception of boundaries by incorporating contour learning with the Sobel operator. Finally, we propose a hybrid multi-task loss function, concurrently concerning tumors' scale and boundary features, to foster interaction across different tasks of dual branches, further improving tumor segmentation. Experimental validation on the publicly available LiTS dataset demonstrates the practical efficacy of each module, with SBCNet yielding competitive results compared to other state-of-the-art methods for liver tumor segmentation.


Assuntos
Algoritmos , Neoplasias Hepáticas , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Fígado/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Redes Neurais de Computação , Aprendizado Profundo
3.
Oncol Lett ; 26(5): 472, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37809044

RESUMO

Numerous agents such as near-infrared dyes that are characterized by specialized cancer imaging and cytotoxicity effects have key roles in cancer diagnosis and therapy via molecularly targeting special biological tissues, organelles and processes. In the present study, a novel fluorescent compound was demonstrated to inhibit cancer cell proliferation in a zebrafish model with slight in vivo toxicity. Further studies demonstrated selective staining of cancer cells and even putative cancer stem cells via accumulation of the dye in the mitochondria of cancer cells, compared with normal cells. Moreover, this compound was also used to image cancer cells in vivo using a zebrafish model. The compound displayed no apparent toxicity to the host animal. Overall, the data indicated that this compound was worthy of further evaluation due to its low toxicity and selective cancer cell imaging and killing effects. It could be a useful tool in cancer research.

4.
Int J Med Robot ; 19(6): e2569, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37634070

RESUMO

During percutaneous coronary intervention, the guiding catheter plays an important role. Tracking the catheter tip placed at the coronary ostium in the X-ray fluoroscopy sequence can obtain image displacement information caused by the heart beating, which can help dynamic coronary roadmap overlap on X-ray fluoroscopy images. Due to a low exposure dose, the X-ray fluoroscopy is noisy and low contrast, which causes some difficulties in tracking. In this paper, we developed a new catheter tip tracking framework. First, a lightweight efficient catheter tip segmentation network is proposed and boosted by a self-distillation training mechanism. Then, the Bayesian filtering post-processing method is used to consider the sequence information to refine the single image segmentation results. By separating the segmentation results into several groups based on connectivity, our framework can track multiple catheter tips. The proposed tracking framework is validated on a clinical X-ray sequence dataset.


Assuntos
Catéteres , Processamento de Imagem Assistida por Computador , Humanos , Raios X , Teorema de Bayes , Processamento de Imagem Assistida por Computador/métodos , Fluoroscopia/métodos
5.
J Neurosci ; 43(37): 6401-6414, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37507230

RESUMO

Older adults exposed to enriched environments (EEs) maintain relatively higher levels of cognitive function, even in the face of compromised markers of brain health. Response speed (RS) is often used as a simple proxy to measure the preservation of global cognitive function in older adults. However, it is unknown which specific selection, decision, and/or motor processes provide the most specific indices of neurocognitive health. Here, using a simple decision task with electroencephalography (EEG), we found that the efficiency with which an individual accumulates sensory evidence was a critical determinant of the extent to which RS was preserved in older adults (63% female, 37% male). Moreover, the mitigating influence of EE on age-related RS declines was most pronounced when evidence accumulation rates were shallowest. These results suggest that the phenomenon of cognitive reserve, whereby high EE individuals can better tolerate suboptimal brain health to facilitate the preservation of cognitive function, is not just applicable to neuroanatomical indicators of brain aging but can be observed in markers of neurophysiology. Our results suggest that EEG metrics of evidence accumulation may index neurocognitive vulnerability of the aging brain.Significance Statement Response speed in older adults is closely linked with trajectories of cognitive aging. Here, by recording brain activity while individuals perform a simple computer task, we identify a neural metric that is a critical determinant of response speed. Older adults exposed to greater cognitive and social stimulation throughout a lifetime could maintain faster responding, even when this neural metric was impaired. This work suggests EEG is a useful technique for interrogating how a lifetime of stimulation benefits brain health in aging.


Assuntos
Encéfalo , Cognição , Humanos , Masculino , Feminino , Idoso , Tempo de Reação , Encéfalo/fisiologia , Cognição/fisiologia , Envelhecimento , Eletroencefalografia/métodos
6.
Sci Rep ; 13(1): 7491, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37161049

RESUMO

Long-term potentiation (LTP) is a form of neuroplasticity commonly implicated in mechanistic models of learning and memory. Acute exercise can boost LTP in the motor cortex, and is associated with a shift in excitation/inhibition (E:I) balance, but whether this extends to other regions such as the visual cortex is unknown. We investigated the effect of a preceding bout of exercise on LTP induction and the E:I balance in the visual cortex using electroencephalography (EEG). Young adults (N = 20, mean age = 24.20) engaged in 20 min of high-intensity interval training (HIIT) exercise and rest across two counterbalanced sessions. LTP was induced using a high frequency presentation of a visual stimulus; a "visual tetanus". Established EEG markers of visual LTP, the N1b and P2 component of the visual evoked potential, and an EEG-derived measure of the E:I balance, the aperiodic exponent, were measured before and after the visual tetanus. As expected, there was a potentiation of the N1b following the visual tetanus, with specificity to the tetanised stimulus, and a non-specific potentiation of the P2. These effects were not sensitive to a preceding bout of exercise. However, the E:I balance showed a late shift towards inhibition following the visual tetanus. A preceding bout of exercise resulted in specificity of this E:I balance shift to the tetanised stimulus, that was not seen following rest. This novel finding suggests a possible exercise-induced tuning of the visual cortex to stimulus details following LTP induction.


Assuntos
Neocórtex , Tétano , Córtex Visual , Adulto Jovem , Humanos , Adulto , Potenciais Evocados Visuais , Exercício Físico
7.
Sheng Li Xue Bao ; 74(2): 177-187, 2022 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-35503065

RESUMO

This paper was aimed to investigate the effect of voluntary wheel running exercise on depression-like behavior induced by chronic water immersion restraint stress (CWIRS) and the underlying mechanism. Sprague-Dawley (SD) rats received CWIRS to induce depression-like behavior and 4-week voluntary wheel running exercise. Meanwhile, the rats were treated with lipopolysaccharide (LPS) or STAT3 over-expression vector (pcDNA-STAT3) by intracerebroventricular injection. Behavioral tests were used to detect depression-like behavior. ELISA assay was used to detect levels of various inflammatory factors in the rat hippocampus. Western blot was used to detect protein expression levels of ionized calcium binding adaptor molecule 1 (Iba1), inducible nitric oxide synthase (iNOS), arginase 1 (Arg1), phosphorylated STAT3 (p-STAT3) and total STAT3 (t-STAT3). The results showed that, compared with stress group, stress + exercise group exhibited improved depression-like behavior, decreased interleukin-1ß (IL-1ß) and IL-6 levels, increased IL-4 and IL-10 levels, down-regulated Iba-1 and iNOS protein expression levels, up-regulated Arg1 protein expression level, and decreased p-STAT3/t-STAT3 ratio in hippocampal tissue. LPS reversed the improving effect of voluntary wheel running exercise on depression-like behavior in rats, and the over-expression of STAT3 reversed the promoting effects of voluntary wheel running on M2 polarization of microglial cells in rat hippocampus and depression-like behavior. These results suggest that voluntary wheel running ameliorates the depression-like behavior induced by CWIRS in rats, and the mechanism may be related to regulating hippocampal microglia polarization via STAT3 signaling pathway.


Assuntos
Depressão , Microglia , Animais , Depressão/etiologia , Hipocampo/metabolismo , Lipopolissacarídeos/metabolismo , Microglia/metabolismo , Atividade Motora , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
8.
J Med Internet Res ; 23(9): e28797, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34528888

RESUMO

BACKGROUND: Although patient portals are widely used for health promotion, little is known about the use of palliative care and end-of-life (PCEOL) portal tools available for patients and caregivers. OBJECTIVE: This study aims to identify and assess the user perspectives of PCEOL portal tools available to patients and caregivers described and evaluated in the literature. METHODS: We performed a scoping review of the academic literature directed by the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) extension for Scoping Review and searched three databases. Sources were included if they reported the development or testing of a feature, resource, tool, or intervention; focused on at least one PCEOL domain defined by the National Coalition for Hospice and Palliative Care; targeted adults with serious illness or caregivers; and were offered via a patient portal tethered to an electronic medical record. We independently screened the titles and abstracts (n=796) for eligibility. Full-text (84/796, 10.6%) sources were reviewed. We abstracted descriptions of the portal tool name, content, targeted population, and reported user acceptability for each tool from included sources (n=19). RESULTS: In total, 19 articles describing 12 tools were included, addressing the following PCEOL domains: ethical or legal (n=5), physical (n=5), and psychological or psychiatric (n=2). No tools for bereavement or hospice care were identified. Studies have reported high acceptability of tools among users; however, few sources commented on usability among older adults. CONCLUSIONS: PCEOL patient portal tools are understudied. As medical care increasingly moves toward virtual platforms, future research should investigate the usability and acceptability of PCEOL patient portal resources and evaluate their impact on health outcomes.


Assuntos
Cuidados Paliativos na Terminalidade da Vida , Portais do Paciente , Assistência Terminal , Idoso , Cuidadores , Humanos , Cuidados Paliativos
9.
J Cogn Neurosci ; 33(6): 1020-1031, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34428789

RESUMO

Current models of perceptual decision-making assume that choices are made after evidence in favor of an alternative accumulates to a given threshold. This process has recently been revealed in human EEG recordings, but an unresolved issue is how these neural mechanisms are modulated by competing, yet task-irrelevant, stimuli. In this study, we tested 20 healthy participants on a motion direction discrimination task. Participants monitored two patches of random dot motion simultaneously presented on either side of fixation for periodic changes in an upward or downward motion, which could occur equiprobably in either patch. On a random 50% of trials, these periods of coherent vertical motion were accompanied by simultaneous task-irrelevant, horizontal motion in the contralateral patch. Our data showed that these distractors selectively increased the amplitude of early target selection responses over scalp sites contralateral to the distractor stimulus, without impacting on responses ipsilateral to the distractor. Importantly, this modulation mediated a decrement in the subsequent buildup rate of a neural signature of evidence accumulation and accounted for a slowing of RTs. These data offer new insights into the functional interactions between target selection and evidence accumulation signals, and their susceptibility to task-irrelevant distractors. More broadly, these data neurally inform future models of perceptual decision-making by highlighting the influence of early processing of competing stimuli on the accumulation of perceptual evidence.


Assuntos
Atenção , Humanos
10.
Cortex ; 142: 122-137, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34265735

RESUMO

Visual processing deficits have been widely reported in developmental dyslexia however the locus of cognitive dysfunction remains unclear. Here, we examined the neural correlates of perceptual decision-making using a dot-motion task and electroencephalography (EEG) and investigated whether presenting deficits were unique to children with dyslexia or if they were also evident in other, typically developing children with equally immature reading systems. Sixty-eight children participated: 32 with dyslexia (DD; 16 females); 21 age-matched controls (AM; 11 females) and 15 reading-matched controls (RM; 9 females). All participants completed a bilaterally presented random-dot-motion task while EEG was recorded. Neural signatures of low level sensory processing (steady state visual evoked potentials; SSVEPs), pre-target attentional bias (posterior α power), attentional orienting (N2), evidence accumulation (centro-parietal positive decision signal; CPP) and execution of a motor response (ß) were obtained to dissect the temporal sequence of perceptual decision-making. Reading profile provided a score of relative lexical and sublexical skills for each participant. Although all groups performed comparably in terms of task accuracy and false alarm rate, the DD group were slower and demonstrated an earlier peak latency, reduced slope and lower amplitude of the CPP compared with both AM and RM controls. Reading profile was found to moderate the relationship between word reading ability, reaction time as well as CPP indices showing that lexical dyslexics responded more slowly and had a shallower slope, reduced amplitude and earlier latency of CPP waveforms than sublexical dyslexics. These findings suggest that children with dyslexia, particularly those with relatively poorer lexical abilities, have a reduced rate and peak of evidence accumulation as denoted by CPP markers yet remain slow in their overt response. This is in keeping with hypotheses that children with dyslexia have impairment in effectively sampling and processing evidence about visual motion stimuli.


Assuntos
Dislexia , Potenciais Evocados Visuais , Criança , Tomada de Decisões , Eletroencefalografia , Feminino , Humanos , Leitura
11.
Biochem Biophys Res Commun ; 524(1): 77-82, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-31980179

RESUMO

OBJECTIVES: Protein arginine methyltransferase 2 (PRMT2) is closely related to the occurrence and development of atherosclerosis. However, its underlying mechanisms remain to be elucidated. The purpose of this study is to observe the effect of overexpression of PRMT2 on the formation of foam cells and to explore its possible mechanism in RAW 264.7 macrophage. METHODS: Lentivirus vector of overexpression PRMT2 (LV-PRMT2) was constructed. LV-PRMT2 and lentivirus vector GV492 were transfected into RAW 264.7 macrophages, positive clone cells were screened by treatment with 4.0 µg/mL puromycin for 4 weeks. The macrophages were treated with ox-LDL (50 µg/mL) for 48 h to induce foaming. The lipid accumulation of macrophages was observed by oil red O staining. The levels of cellular total cholesterol (TC), free cholesterol (FC) and cholesteryl ester (CE) were measured by high performance liquid chromatography (HPLC) assays. The cholesterol efflux of macrophages was tested by the [3H] labeled cholesterol. The expressions of ATP binding cassette transporter A1 (ABCA1), ATP binding cassette transporter G1 (ABCG1), CD36 and scavenger receptor A1 (SR-A1) in macrophages were measured by Western Blot. RESULTS: The results showed that LV-PRMT2 and lentivirus vector has been successfully transfected into RAW 264.7 macrophage. Compared with the Vector group, the mRNA and protein expressions of PRMT2 were significantly up-regulated (P < 0.05). Compared with Control group, the expression of PRMT2 was significantly down-regulated in ox-LDL group (P < 0.05). A large number of red lipid droplets appeared in the cells in Vector group. Compared with Vector group, lipid droplets, the levels of TC, FC and CE and CE/TC, cholesterol efflux rate and expression of ABCA1 in RAW 264.7 macrophage was significantly decreased in LV-PRMT2 group (all P < 0.05). There was no significant difference about the expressions of ABCG1, CD36 and SR-A1 between LV-PRMT2 group and Vector group (all P > 0.05). CONCLUSIONS: Overexpression of PRMT2 inhibits the formation of foam cell induced by ox-LDL in RAW 264.7 macrophage, and the mechanism may be related to the increase of ABCA1 expression and ABCA1 mediated cholesterol efflux.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/metabolismo , Células Espumosas/metabolismo , Lipoproteínas LDL/metabolismo , Proteína-Arginina N-Metiltransferases/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Arginina/metabolismo , Aterosclerose/metabolismo , Transporte Biológico , Antígenos CD36/metabolismo , Regulação da Expressão Gênica , Lentivirus/genética , Metilação , Camundongos , Células RAW 264.7 , RNA Mensageiro/metabolismo , Receptores Depuradores/metabolismo , Transfecção
12.
Sci Total Environ ; 708: 134596, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31780158

RESUMO

In this study, the effects of nitrogen and phosphorus supply on biodiesel production from Scenedesmus obliquus with glucose as the carbon source were investigated. It was found that sufficient phosphorus could further improve biodiesel production under nitrogen starvation. S. obliquus was cultivated in soybean processing wastewater. The removal efficiencies of carbon oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) after 8-day cultivation were 72%, 95%, and 54%, respectively. Moreover, the fatty acid productivity after eight-day cultivation reached as high as 99.3 mg·L-1·d-1, which was 1.15 times higher than the highest efficiency using a glucose culture. This result was due to two naturally-formed stages occurring with sufficient phosphorus: nitrogen sufficiency stage for biomass and nitrogen starvation stage for lipid accumulation. It verified the conclusion of the roles of nitrogen and phosphorus obtained in the glucose culture and provided an economic and environmentally friendly choice for biodiesel production with efficient soybean wastewater treatment.


Assuntos
Microalgas , Scenedesmus , Biocombustíveis , Biomassa , Glucose , Nitrogênio , Fósforo , Glycine max , Águas Residuárias
13.
PhytoKeys ; 128: 47-55, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379456

RESUMO

Clematisguniuensis sp. nov., a new narrowly endemic species of Clematis, is described and illustrated from the Huangshan Mountains of Eastern China. A description of C.guniuensis is presented along with illustrations, photographs and diagnostic differences between the new species and its putative close allies.

14.
Am J Transl Res ; 11(6): 3461-3471, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31312358

RESUMO

Prostate cancer is the second most common malignancy among men and causes a myriad of health problem for males that are diagnosed with the cancer. Although the 5-year relative survival rate of prostate cancer patients has been significantly increased due to prostate-specific antigen testing and treatment advances, patients that develop metastatic castrate-resistant prostate cancer continue to have poor survival rates. Thus, it is critical to discover new therapeutics to treat prostate cancer. Diosgenin is a steroidal saponin from Trigonella foenum graecum, which has been previously identified to exert anti-tumor properties. Neural precursor cell expressed developmentally down-regulated protein 4 (NEDD4) is an E3 ligase that degrades multiple different proteins, and plays an oncogenic role in human cancer. In this study, we explore the molecular mechanism by which diosgenin mediates anti-tumor effects in prostate cancer cells. We found that diosgenin treatment led to cell growth inhibition, apoptosis and cell cycle arrest. Notably, we found that diosgenin inhibited the expression of NEDD4 in prostate cancer cells. Furthermore, overexpression of NEDD4 overcame the diosgenin-mediated anti-tumor activity, while downregulation of NEDD4 promoted the diosgenin-induced anti-cancer function in prostate cancer cells. Our findings indicate that diosgenin is a potential new inhibitor of NEDD4 in prostate cancer cells.

15.
Brain ; 142(3): 719-732, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30689734

RESUMO

Disorders of motivation, such as apathy, are common in Parkinson's disease, and a key feature of such disorders is a greater aversion to effort. In humans, the experience of cognitive effort is ubiquitous, and cognitive apathy has traditionally been considered distinct and separable from other subtypes. Surprisingly, however, the neurobiology of cognitive motivation is poorly understood. In particular, although dopamine has a well-characterized role in incentivizing physically effortful behaviour, a critical, unresolved issue is whether its facilitatory role generalizes to other domains. Here, we asked how dopamine modulates the willingness of patients with Parkinson's disease to invest cognitive effort in return for reward. We tested 20 patients with idiopathic Parkinson's disease across two counterbalanced sessions-ON and OFF their usual dopaminergic medication-and compared their performance to 20 healthy age-matched controls. We applied a novel task in which we manipulated cognitive effort as the number of rapid serial visual presentation streams to which participants had to attend. After training participants to ceiling performance, we then asked them to choose between a low-effort/low-reward baseline option, and a higher-effort/higher-reward offer. Computational models of choice behaviour revealed four key results. First, patients OFF medication were significantly less cognitively motivated than controls, as manifest by steeper cognitive effort discounting functions in the former group. Second, dopaminergic therapy improved this deficit, such that choices in patients ON medication were indistinguishable from controls. Third, differences in motivation were also accompanied by independent changes in the stochasticity of individuals' decisions, such that dopamine reduced the variability in choice behaviour. Finally, choices on our task correlated uniquely with the subscale of the Dimensional Apathy Scale that specifically indexes cognitive motivation, which suggests a close relationship between our laboratory measure of cognitive effort discounting and subjective reports of day-to-day cognitive apathy. Importantly, participants' choices were not confounded by temporal discounting, probability discounting, physical demand, or varying task performance. These results are the first to reveal the central role of dopamine in overcoming cognitive effort costs. They provide an insight into the computational mechanisms underlying cognitive apathy in Parkinson's disease, and demonstrate its amenability to dopaminergic therapy. More broadly, they offer important empirical support for prominent frameworks proposing a domain-general role for dopamine in value-based decision-making, and provide a critical link between dopamine and multidimensional theories of apathy.


Assuntos
Cognição/efeitos dos fármacos , Dopamina/farmacologia , Doença de Parkinson/tratamento farmacológico , Idoso , Apatia , Simulação por Computador , Tomada de Decisões , Dopamina/metabolismo , Dopaminérgicos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação/efeitos dos fármacos , Esforço Físico , Recompensa
16.
Bull Environ Contam Toxicol ; 103(1): 127-132, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30671617

RESUMO

This study examined the selenium (Se) and cadmium (Cd) uptake by rice from soil and analyzed the relationship between Se and Cd in naturally occurred Se-rich paddy fields with a high geological background of Cd. Significant correlations were observed between soil Se and plant biomass Se, but not between soil Cd and plant biomass Cd. High concentrations of Cd were detected in rice plants and particularly in rice grains, suggesting potential health risks to human. Contrary to results from other previous studies, our results showed that high soil Se did not reduce Cd uptake by rice, although it decreased the availability of Cd in soil. Rather, soil Se and internal Se pool in rice were positively correlated to the transfer of Cd from root to straw. The effect of Se on the uptake and translocation of Cd in rice in field is therefore different from those in pot experiments.


Assuntos
Cádmio/metabolismo , Oryza/metabolismo , Selênio/química , Poluentes do Solo/metabolismo , Transporte Biológico , Biomassa , Cádmio/análise , Raízes de Plantas/efeitos dos fármacos , Solo
17.
Opt Express ; 26(21): 26925-26932, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30469770

RESUMO

Double-end polarized pumping scheme combined with off-axis pumping technique has been first introduced to generate vortex beams in a z-type cavity. By employing double-end pumping, two different transverse modes can be excited simultaneously. The phase delay between these two modes can be finely tuned by manipulating the cavity structure. Direct emission of a chirality controllable Laguerre Gaussian LG01 vortex beam with slope efficiency of more than 40% has been realized by a double-end polarized pumped Yb:KYW laser. Other modes, such as dual-LG01 mode, cross-shaped mode, and LG10 mode, have also been demonstrated from our laser setup.

18.
Opt Express ; 26(14): 18164-18170, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-30114096

RESUMO

Wavelength- and OAM- tunable laser with large tunable range is the key source for the application in large capacity optical communications. In this paper, we demonstrate a wavelength- and OAM-tunable vortex laser in a 1.2 W single mode fiber coupled LD pumped Yb:phosphate laser. A z-type cavity has been used to precisely control the laser mode diameter. A thin film polarizer (TFP) is inserted to finely control the intra-cavity loss and tune the wavelength. Corresponding laser fundamental mode to pump beam ratio has been optimized to decrease the pump threshold for high order HG mode running. A pair of cylindrical lenses has been used to convert the HG mode to vortex output. The vortex beam with OAM-tunable range from 1h to 14 h with wavelength tuning range of ~36.2 nm for LG0,1 vortex beam, and ~14.5 nm for LG0,14 vortex beam at pump power of only 1.2 W have been realized, which is the largest tuning range of both OAM and wavelength at ~1 W pump power range to the best of our knowledge.

19.
Appl Plant Sci ; 6(4): e1145, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30131887

RESUMO

PREMISE OF THE STUDY: Microsatellite markers were developed in Torreya yunnanensis (Taxaceae) to investigate the genetic diversity, phylogeography, and population structure of the species. METHODS AND RESULTS: Sixteen primer sets were identified using Illumina 2 × 100-bp paired-end sequencing and bioinformatic screening. Most primers also amplified in T. fargesii, T. grandis, T. jackii, and T. nucifera. CONCLUSIONS: These results indicate the utility of these microsatellite markers in T. yunnanensis for future studies of molecular ecology as well as their applicability across the genus.

20.
PeerJ ; 6: e4946, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29910979

RESUMO

The limestone karst area of South China is a major biodiversity hotspot of global terrestrial biomes. During extensive field work on the Guangxi limestone formations, two unknown species of Gesneriaceae were collected. After conducting a comprehensive study of the literature and herbarium specimens, Primulina davidioides and P. hiemalis are recognized as two species new to science, and described and illustrated here. P. davidioides is morphologically close to P. lunglinensis based on the shape of the leaf and flower, but it can be easily distinguished by the shape of the bracts, corolla and stigma, indumentum of peduncles, pedicels and pistil and number of staminodes. P. hiemalis is closely relate to P. luzhaiensis in vegetative appearance, but differs in the shape of the calyx and stigma, number of bracts and staminodes, indumentum of the leaf blade and peduncle, and position of stamens in the corolla tube. Considering that not enough is known about their populations, it is proposed that their conservation statuses should currently be classed as data deficient (DD) according to the IUCN Red List Category and Criteria.

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