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1.
Nature ; 626(7999): 523-528, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38356068

RESUMO

Spatial, momentum and energy separation of electronic spins in condensed-matter systems guides the development of new devices in which spin-polarized current is generated and manipulated1-3. Recent attention on a set of previously overlooked symmetry operations in magnetic materials4 leads to the emergence of a new type of spin splitting, enabling giant and momentum-dependent spin polarization of energy bands on selected antiferromagnets5-10. Despite the ever-growing theoretical predictions, the direct spectroscopic proof of such spin splitting is still lacking. Here we provide solid spectroscopic and computational evidence for the existence of such materials. In the noncoplanar antiferromagnet manganese ditelluride (MnTe2), the in-plane components of spin are found to be antisymmetric about the high-symmetry planes of the Brillouin zone, comprising a plaid-like spin texture in the antiferromagnetic (AFM) ground state. Such an unconventional spin pattern, further found to diminish at the high-temperature paramagnetic state, originates from the intrinsic AFM order instead of spin-orbit coupling (SOC). Our finding demonstrates a new type of quadratic spin texture induced by time-reversal breaking, placing AFM spintronics on a firm basis and paving the way for studying exotic quantum phenomena in related materials.

2.
Curr Ther Res Clin Exp ; 98: 100700, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37123033

RESUMO

Background: Antisense transcript of the B-cell translocation gene 3 (ASBEL) is a highly conserved antisense non-coding RNA (ncRNA) and participates in a variety of biological processes. However, the ASBEL expression status in pancreatic ductal adenocarcinoma (PDAC) and its correlation with BTG3 expression and tumor cell progression were not completely clear. Objective: We conducted cell experiments and animal experiments to confirm that ASBEL plays a crucial role in the tumorigenesis of PDAC by targeting BTG3. Methods: ASBEL regulation in PDAC tumorigenesis was evaluated using Western blotting, quantitative polymerase chain reaction, Cell Counting Kit-8 assay, flow cytometry, and cell transfection. We also evaluated the expression of ASBEL and BTG3 in tumor tissues and cells using Western blotting and quantitative real-time polymerase chain reaction. Finally, we explored the role of ASBEL in tumor development by silencing or overexpressing ASBEL gene in AsPC-1 or CFPAC-1 cells, respectively, and evaluated the antitumor activity in vivo using an ASBEL antagonist. Results: Our study revealed the expression of ASBEL in all pancreatic cell lines. The expression level of ASBEL in tumor tissues was found to be higher than that of paracarcinomatous tissues. ASBEL suppresses expression of BTG3, enhances proliferation and suppresses apoptosis, and promotes migration and invasion in pancreatic cancer cell. Antagonist regulates the expression of ASBEL in AsPC-1, and suppresses tumor growth in xenograft mouse model. Conclusions: Our results indicate that ASBEL may play a tumor-promoting factor in PDAC by targeting BTG3 and could be as an important biomarker for PDAC treatment. (Curr Ther Res Clin Exp. 2023; 84:XXX-XXX).

3.
Adv Sci (Weinh) ; : e2406529, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39303163

RESUMO

Recently, unconventional antiferromagnets that enable the spin splitting (SS) of electronic states have been theoretically proposed and experimentally realized, where the magnetic sublattices containing moments pointing at different directions are connected by a novel set of symmetries. Such SS is substantial, k-dependent, and independent of the spin-orbit coupling (SOC) strength, making these magnets promising materials for antiferromagnetic spintronics. Here, combined with angle-resolved photoemission spectroscopy (ARPES) and density functional theory (DFT) calculations, a systematic study on CrSb, a metallic spin-split antiferromagnet candidate with Néel temperature TN = 703 K, is conducted. The data reveal the electronic structure of CrSb along both out-of-plane and in-plane momentum directions, rendering an anisotropic k-dependent SS that agrees well with the calculational results. The magnitude of such SS reaches up to at least 0.8 eV at non-high-symmetry momentum points, which is significantly higher than the largest known SOC-induced SS. This compound expands the choice of materials in the field of antiferromagnetic spintronics and is likely to stimulate subsequent investigations of high-efficiency spintronic devices that are functional at room temperature.

4.
World J Clin Cases ; 10(27): 9790-9797, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36186218

RESUMO

BACKGROUND: Synchronous primary cancers (SPCs) have become increasingly frequent over the past decade. However, the coexistence of duodenal papillary and gallbladder cancers is rare, and such cases have not been previously reported in the English literature. Here, we describe an SPC case with duodenal papilla and gallbladder cancers and its diagnosis and successful management. CASE SUMMARY: A 68-year-old Chinese man was admitted to our hospital with the chief complaint of dyspepsia for the past month. Contrast-enhanced computed tomography of the abdomen performed at the local hospital revealed dilatation of the bile and pancreatic ducts and a space-occupying lesion in the duodenal papilla. Endoscopy revealed a tumor protruding from the duodenal papilla. Pathological findings for the biopsied tissue revealed tubular villous growth with moderate heterogeneous hyperplasia. Surgical treatment was selected. Macroscopic examination of this surgical specimen revealed a 2-cm papillary tumor and another tumor protruding by 0.5 cm in the gallbladder neck duct. Intraoperative rapid pathology identified adenocarcinoma in the gallbladder neck duct and tubular villous adenoma with high-grade intraepithelial neoplasia and local canceration in the duodenal papilla. After an uneventful postoperative recovery, the patient was discharged without complications. CONCLUSION: It is essential for clinicians and pathologists to maintain a high degree of suspicion while evaluating such synchronous cancers.

5.
World J Clin Cases ; 8(20): 4993-4998, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33195672

RESUMO

BACKGROUND: Spontaneous bladder rupture is relatively rare, and common causes of spontaneous bladder rupture include bladder diverticulum, neurogenic bladder dysfunction, gonorrhea infection, pelvic radiotherapy, etc. Urinary bladder perforation caused by urinary catheterization mostly occurs during the intubation process. CASE SUMMARY: Here, we describe an 83-year-old male who was admitted with 26 h of middle and upper abdominal pain and a history of long-term catheterization. Physical examination and computed tomography of the abdomen supported the diagnosis of diffuse peritonitis, most likely from a perforated digestive tract organ. Laparoscopic exploration revealed a possible digestive tract perforation. Finally, a perforation of approximately 5 mm in diameter was found in the bladder wall during laparotomy. After reviewing the patient's previous medical records, we found that 1 year prior the patient underwent an ultrasound examination showing that the end of the catheter was embedded into the mucosal layer of the bladder. Therefore, the bladder perforation in this patient may have been caused by the chronic compression of the urinary catheter against the bladder wall. CONCLUSION: For patients with long-term indwelling catheters, there is a possibility of bladder perforation, which needs to be dealt with quickly.

6.
World J Clin Cases ; 7(15): 2094-2102, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31423443

RESUMO

BACKGROUND: Duplication of the appendix is an infrequent congenital malformation with a complex classification. The horseshoe appendix is a subtype of the duplex appendix and is rarely reported in the literature. Endometriosis is a common gynecological disease that rarely occurs in the appendix. Moreover, horseshoe appendix combined with endometriosis has not been previously reported. CASE SUMMARY: Here, we describe a 44-year-old woman who was admitted with a 1-d history of migratory lower right quadrant pain. Physical examination was consistent with the signs of acute appendicitis. The patient underwent an emergency exploratory laparotomy. The distal tip of the appendix was in contact with the cecum by another base, or "horseshoe appendix". In addition, a small intestinal mass and an ovarian mass were identified. Subsequently, appendectomy, partial resection of the small intestine, and right oophorectomy were successively performed. The histopathology confirmed the diagnosis of acute inflammation of the duplex appendix with endometriosis, small intestine endometriosis, and ovarian endometriosis. CONCLUSION: Surgeons need to be aware of the possibility of the duplex appendix when performing an appendectomy, and this study emphasizes the importance of exploring the entire abdomen.

7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(1): 47-50, 2008 Jan.
Artigo em Zh | MEDLINE | ID: mdl-18422117

RESUMO

Carbon supported PtSn catalyst (PtSn/C) was prepared by a modified polyol method and characterized by means of XRD. It was showed that the metal particle size was 2.2 nm and the unit cell parameter increased compared with Pt/C. In situ time-resolved Fourier transform infrared spectroscopy (TRFTIRS) was used to study the electrooxidation of ethanol on PtSn/C catalyst. COL was the main poison species adsorbed on the active sites to inhibit the further reaction of ethanol electrooxidation. Acetaldehyde and acetic acid were found to be the products of ethanol electrooxidation as competing reactions with ethanol dissociation when the potential was up to 0.3 V, which reduced the poisoning effect. The selectivity of acetic acid among the products was improved with the increase in the potential and reaction time. CO2, which appeared at 0.4 V, was the final product and yielded from the oxidation of COL. The catalytic mechanism of PtSn/C towards ethanol electrooxidation was analyzed based on the results.

9.
Nat Commun ; 9(1): 4488, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367062

RESUMO

Today East Asia harbors many "relict" plant species whose ranges were much larger during the Paleogene-Neogene and earlier. The ecological and climatic conditions suitable for these relict species have not been identified. Here, we map the abundance and distribution patterns of relict species, showing high abundance in the humid subtropical/warm-temperate forest regions. We further use Ecological Niche Modeling to show that these patterns align with maps of climate refugia, and we predict species' chances of persistence given the future climatic changes expected for East Asia. By 2070, potentially suitable areas with high richness of relict species will decrease, although the areas as a whole will probably expand. We identify areas in southwestern China and northern Vietnam as long-term climatically stable refugia likely to preserve ancient lineages, highlighting areas that could be prioritized for conservation of such species.

10.
Am Nat ; 159(5): 498-508, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-18707432

RESUMO

Habitat heterogeneity plays a key role in the dynamics and structures of communities. In this article, a two-species metapopulation model that includes local competitive dynamics is analyzed to study the population dynamics of two competing species in spatially structured habitats. When local stochastic extinction can be ignored, there are, as in Lotka-Volterra equations, four outcomes of interspecific competition in this model. The outcomes of competition depend on the competitive intensity between the competing pairs. An inferior competitor and a superior competitor, or two strongly competing species, can never stably coexist, whereas two weak competitors (even if they are very similar species) may coexist over the long term in such environments. Local stochastic extinction may greatly affect the outcomes of interspecific competition. Two competing species can or cannot stably coexist depending not only on the competitive intensity between the competing pairs but also on their precompetitive distributions. Two weak competitors that have similar precompetitive distributions can always regionally coexist. Two strongly competing species that competitively exclude each other in more stable habitats may be able to stably coexist in highly heterogenous environments if they have similar precompetitive distributions. There is also a chance for an inferior competitor to coexist regionally or even to exclude a superior competitor when the superior competitor has a narrow precompetitive distribution and the inferior competitor has a wide precompetitive distribution.

11.
Zhonghua Liu Xing Bing Xue Za Zhi ; 30(4): 326-30, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-19731520

RESUMO

OBJECTIVE: To understand the dietary nutrients among rural stranded children. METHODS: 2551 children aged 2 to 7, including 1278 stranded children in the rural areas and another 127 children served as controls were selected, using multistage stratified cluster random sampling. Dietary survey was performed with three-day weighing dietary method and questionnaire on food intake. Data on diet were analyzed and evaluated by the Dietary Reference Intakes (DRIs) recommend by Chinese Nutrition Society, to evaluate the levels on energy and nutrient intake among stranded children in the rural areas. RESULTS: The dietary pattern among rural stranded children mainly consisted of grains and vegetables, but the intakes of animal products, fruits, and snacks were significantly less than in the control group. The intakes of three major energy-producing nutrients were below the recommend nutrient intake. Minerals as calcium, zinc, selenium, kalium and vitamins as vitamin A, B1, B2 were insufficient. Most of the rural stranded children took nutrients insufficiently, with 50% lack of adequate energy and 80% of protein, 90% of minerals (calcium, zinc etc.) and vitamins (vitamin BI and vitamin B2 etc.). Sources from high quality protein was insufficient, only consisting 35% of the total protein, but overabundant (over 64%) from the plants. The intake of plant-sources iron was overabundant, accounted for 87%. CONCLUSION: The dietary pattern was unsatisfactory with insufficient intake of energy-sources proteins and some nutrients. The sources of energy, protein, and iron were mostly obtained from underbalanced foods. It is necessary to improve the dietary nutrients status among rural stranded children aged 2-7 years.


Assuntos
Inquéritos sobre Dietas , Dieta/estatística & dados numéricos , Criança , Pré-Escolar , China , Humanos , Estado Nutricional , População Rural
12.
Zhonghua Liu Xing Bing Xue Za Zhi ; 29(9): 860-4, 2008 Sep.
Artigo em Zh | MEDLINE | ID: mdl-19173843

RESUMO

OBJECTIVE: To understand the status on care and nutrition of children living in the rural areas (so called 'left-behind' children) while their parents were seeking for jobs in the urban areas. METHODS: Cross-sectional study was employed in this investigation. The group of 'left-behind' children (n = 774) and the comparison group (n = 774) were identified. The ascertainment methods mainly included questionnaire, anthropometrics measurements, food-frequency, and laboratory examination. RESULTS: Data from this study revealed that the guardians of the 'left-behind' children had less ability to ensure daily food that the children demanded than the control group and the 'left-behind' children were more likely to be poorly attended (chi2 = 6.671, P = 0.036; xhi2 = 15.053, P = 0.001). Mothers who chose to work outside of their households would tend to choose bottle-feeding or decrease the duration of breastfeeding for their infants (chi2 = 5. 051, P = 0.031; t = -7.201, P = 0.001). The intake of milk and bean products in children younger than 2 years old and cereal intake in children aged 2 to 4 in the group of 'left-behind' children were obviously lower than that seen in the control group (t = -2.150, P = 0.032; t = -2.054, P = 0.040 respectively). The 'left-behind' children were in high prevalence of anemia, and showed significant difference when comparing with the control group (chi2 = 4.560, P = 0.033). CONCLUSION: Children under 'left-behind' situation were in poor nutrition. Recognition of this situation by the communities, parents and extended families would facilitate more attention and effective intervention programs to improve the situation.


Assuntos
Educação Infantil , Estado Nutricional , Criança , Pré-Escolar , China , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , População Rural
13.
Ying Yong Sheng Tai Xue Bao ; 18(11): 2540-7, 2007 Nov.
Artigo em Zh | MEDLINE | ID: mdl-18260461

RESUMO

A valuation study was conducted in Sanggou Bay, a typical and intensive coastal aquaculture area in China Yellow Sea. The results showed that the total value of ecosystem services (VES) in Sanggou Bay was 6.07 x 10(8) Yen in 2003, with an average unit VES being 4.24 x 10(6) Yen x km(-2). Within the total VES, the provision services, regulation services, and culture services accounted for 51.29%, 17.34%, and 31.37%, respectively. Among the eight primary and secondary services valuated in Sanggou Bay, food provision services held the highest value (50.45%), followed by tourism and entertainment services (29.89%) and climate regulation services (9.18%). Harmful organism and disease control services have the lowest value (0.0017%). The aquaculture activities had greater contributions to the local social economy, environmental regulation, and social culture. Aquaculture activities, especially macro-algae farming, are of significance in maintaining and enhancing the ecosystem services.


Assuntos
Conservação dos Recursos Naturais/economia , Ecologia/economia , Ecossistema , Monitoramento Ambiental , Aquicultura , China , Análise Custo-Benefício , Oceanos e Mares
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