Nominal 1 at.% Al-doped Zn sub(1-x)Mg sub(x)O (x = 0-8 at.%) thin films are prepared by the sol-gel method. The codoping films retain the hexagonal wurtzite structure of ZnO, and show preferential ...c-axis orientation. The effect of annealing ambient (in vacuum and nitrogen) on the optical and electrical properties of (Mg,Al)-codoped ZnO films is investigated. The transmittance of the codoping films is obviously degraded to 50-60% by vacuum annealing, but is enhanced to 70-80% after nitrogen annealing. Both the carrier concentration and the Hall mobility decrease, and the resistivity increases with the widening of the band gap in films treated in vacuum. However, the carrier concentration of films annealed in nitrogen displays fluctuations with increasing x, and the carrier concentrations of films with x = 2 and 4% are higher than those of other films. The initial band gap increase of nitrogen-annealed films might be attributed both to Mg doping and to the Burstein-Moss effect due to the N sub(O)-(N sub(2)) sub(O) complex donors. In view of the transmittance and conductivity, nitrogen annealing might be a more appropriate post-annealing method than vacuum annealing for (Mg,Al)-codoped ZnO films to fulfil the requirements of transparent conducting oxide.
Two-dimensional silver nanodisks were self-assembled in ⟨111⟩ crystallography orientations forming a three-dimensional architecture. The kinetics studies of interface growth reveal that the Cu2+ ion ...diffusion interface diminished the concentration convection and electric convection at the growing interface. With the fluctuation greatly reduced, the effect of lattice anisotropy of the growing interface starts to dominate, which induces highly faceted regular patterns with a stable growing interface. First-principles density functional theory calculations clarified that the silver patterns grow consistently with their thermodynamic character of the face-centered-cubic phase, and show the crystallographical orientation.
Our first-principles investigation on the interaction of vacancies, interstitial H, and solute Cr atoms demonstrates although both Cr and Fe hydrides are unstable as stand-along materials, atomic ...layers of (Cr,Fe)H2 are stable in H-supersaturated Fe-Cr alloy. They have coherent interfaces with the Fe matrix, but still can serve as sinks for self-interstitials, vacancies, and also He atoms, improving the irradiation resistance to void swelling. Manganese will enhance the stability of the thin-film, while C and W have strong destroying effect. This finding points to new possibilities of stabilizing an otherwise unstable compound by constraining it in an alloy.
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To summarize the clinical features of different racial patients with celiac disease (CD) and analyze the disease prevalence, diagnosis and treatment in Chinese population.
All the patients were ...diagnosed as CD and enrolled in Beijing United Family Hospital between January 2005 and July 2015.Clinical data including nationality, age, symptoms, endoscopic and pathological findings, outcome were collected and compared in patients from different countries.
A total of 87 patients were enrolled including 63 Caucasians, 18 Asian patients and 6 Middle East patients.The peak age of disease onset was 40-60 years old.Patients with typical symptoms such as chronic diarrhea and weight loss only accounted for 20.7%(18/87) and 9.2%(8/87) respectively.Some patients presented with nonspecific symptoms such as abdominal pain and bloating 32.2%(28/87), even constipation 5.7%(5/87).13.8%(12/87) patients were previously diagnosed as irritable bowel syndrome.The incidence of abdominal pain, bloating, diarrhea and constipation between Asians and Caucasians had no statistical significance (P>0.05); but the proportions of weight loss, growth retardation, iron deficiency anemia and dermatitis herpetiformis in Asian group were significantly higher than that in Caucasian group (P<0.05). IgA type of anti-gliadin antibody (AGA), endomysium antibody (EMA) and tissue transglutaminase antibody (tTGA) were dominant autoimmune antibodies in patients with CD, which accounted for 58.6%(51/87), 44.8%(39/87) and 36.8%(32/87) respectively.The endoscopy showed that the lesion of CD was mainly located in small intestine, with reducing severity from the proximal to the distal small intestine.The lesions of duodenal bulb and descending duodenum appeared more significant in Asian group.Accordingly pathological intestinal atrophy and the degree of intraepithelial lymphocytosis were more severe in Asian patients.All 87 cases took the gluten-free diet (GFD). Eighty-one cases received serological follow up and 8 with endoscopic intestinal biopsy.The celiac disease antibodies in 47 patients turned negative from 6-9 months after GFD treatment, while 34 patients turned negative from 12-18 months after GFD.All patients reported disease remission to some extent.After 1 year GFD treatment, the pathology of endoscopic intestinal biopsy in 8 patients showed significant improvement of villous atrophy and lymphocyte infiltration.
CD patients with typical clinical manifestations are not the majority.Serological celiac disease antibodies (AGA, EMA and tTGA) have a high diagnostic value.GFD treatment is effective on majority of celiac patients.Clinical manifestations, endoscopy, intestinal pathology, and response to GFD in Chinese patients are not the same as Caucasians.Clinicians need to pay attention to the differential diagnosis.
In April 2011, a survey of diseases was conducted on strawberry plants grown in greenhouses in the town of Xingshou, Changping District, Beijing, China. A tan-brown leaf spot with the presence of ...pink spore masses was observed on older leaves of strawberry plants. In general, the leaf spots began as small, round, water-soaked lesions in the middle or on the margin of leaves, which enlarged gradually up to 1 to 3 cm in diameter and were circular or irregular and brown to dark brown. Occasionally, the center of some spots cracked in the middle lesion under dry conditions. Eventually, black sporodochia were produced on the upper surface of spots and exuded pink conidial masses under humid conditions. Fungal structures were taken directly from the diseased leaves and examined microscopically for morphological characteristics. Sporodochia, 172 to 451 × 138 to 343 μm, were dark and suborbicular. Conidiophores, 8.4 to 48.3 × 0.8 to 2.1 μm, were hyaline, unicellular, and cylindrical. Conidia, 3.1 to 10.2 × 1.5 to 3.0 μm, were hyaline, aseptate, and canoe-shaped to allantoid, forming singly. For further study, the fungus was isolated in pure culture on potato dextrose agar (PDA) medium from symptomatic leaf tissue. In culture, the mycelium was white at first and then changed to brownish. The sporodochia were light colored at first and turned brownish or almost black in older cultures. To identify the fungus, the ITS1-5.8S-ITS2 rDNA region of the isolate was amplified by PCR with primers ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3') and sequenced. The 462-nt sequence (GenBank Accession No. JQ995228) was identical to that of Pilidium concavum (1). To validate Koch's postulates, pathogenicity was tested by inoculating 20 leaves on 10 healthy strawberry plants with a mycelial plug from a 15-day-old colony (0.5 cm in diameter). Controls were treated with plugs of PDA medium. The inoculated and control plants were then maintained in growth chambers at 25°C (12 h of light per day, 80% humidity). After 12 days, 100% of the inoculated leaves showed symptoms identical to those observed on leaves in the field while the control leaves remained healthy. The original fungus was reisolated from inoculated leaves showing the symptoms. Thus, it was concluded that the fungus was the causal organism of the leaf spot. On the basis of morphological characteristics, molecular features, and pathogenicity tests, the pathogen of tan-brown leaf spot on strawberry was identified as P. concavum. To our knowledge, this is the first report of P. concavum causing tan-brown leaf spot on strawberry in China. This fungus was reported to cause leaf spot on Paeonia suffruticosa in China (2). It also caused tan-brown rot on strawberry fruit in our pathogenicity test. References: (1) L. Cardin et al. Plant Dis. 93:548, 2009. (2) Y. B. Duan et al. Plant Dis. 94:271, 2010.
Objective
von Hippel-Lindau (VHL) disease is a hereditary tumor syndrome predisposed to the development of tumors in a variety of body organs. The major etiopathogenesis of VHL is a mutation of the ...VHL tumor-suppressor gene on the short arm of chromosome 3 (3p25–26). We report on the clinical and molecular features of four Chinese kindreds with VHL disease.
Materials and methods
The VHL gene was screened for mutation using a direct DNA sequencing analysis and a multiplex ligation-dependent probe amplification (MLPA) for 44 volunteers from these four families. Any unaffected person, with germline VHL gene mutation, was required to undergo further examination, surveillance and treatment.
Results
The main lesions and the average diagnostic year of the 20 patients were central nervous system hemangioblastoma (60 %, 34.92 years), renal lesion (60 %, 39.08 years), pancreatic lesion (60 %, 37.67 years), adrenal pheochromocytoma (25 %, 37.8 years) and retinal hemangioblastoma (10 %, 25.5 years). Direct sequencing detected nucleotide substitutions or small deletions in three families and MLPA revealed exon 1 deletion in family A. The five asymptomatic patients were initially diagnosed by genetic analysis and verified radiologically or surgically.
Conclusions
The spectrum of clinical manifestation of VHL in the mainland Chinese population is similar to the observation in Western kindreds. Genetic testing, which plays a crucial role in early diagnosis asymptomatic patients, is obviously superior to clinical informations when diagnosing VHL disease. The members of VHL disease family may benefit from pedigree study, genetic testing, periodic follow-up, early diagnosis and prompt treatment.
Rewatering after drought is beneficial to plants subjected to moderate drought stress, and selenium (Se) could increase the tolerance of plants to stressful environment. The role of Se in rewatering ...of drought-treated wheat seedlings (Triticum aestivum L., cv Hengmai5229) was studied. The objective was to elucidate whether Se could improve recovery of wheat seedlings at rewatering after drought stress. Drought stress induced a significant reduction in growth parameters, total chlorophyll and soluble protein contents, and increased the rate of superoxide radical (O 2 ·− ) production, MDA content, and the activities of peroxidase, catalase (CAT), and superoxide dismutase in wheat seedlings. Rewatering after drought did not significantly affect biomass accumulation of seedlings over drought treatment, although it decreased the rate of O 2 ·− production and MDA content. However, the combined treatment of rewatering and Se evidently promoted biomass accumulation of seedlings over drought treatment and rewatering alone; and the rate of O 2 ·− production, MDA content, soluble protein content and CAT activity were recovered to the control values. This indicates that Se improved recovery of wheat seedlings at rewatering after drought stress.
This article aims to understand the cytogenetic characteristics of Barbus capito and to provide the theoretical basis for the establishment of an idioplasmatic standard and the genetic breeding of ...this species.
Aim: To investigate the characteristic of community‐associated methicillin‐resistant staphylococcus aureus (CA‐MRSA) skin and soft tissue infections (SSTIs) among children in China.
Methods: ...Forty‐seven children with CA‐MRSA SSTIs were enrolled in this study. Clinical information was collected and analysed. The strains from the children were analysed by multilocus sequence typing (MLST), staphylococcus cassette chromosome mec (SCCmec) typing and spa typing. The Panton‐Valentine leukocidin (PVL) gene was also detected.
Results: The majority of the 47 cases were impetigo (20; 42.6%) and abscesses (14; 29.8%). The rest was cellulites, infected wounds, omphalitis, paronychia and conjunctivitis combined folliculitis. Thirty‐two of the isolates (68.1%) were PVL‐positive, and the abscesses infected with PVL‐positive strains usually required incision and drainage (87.5% vs. 16.7%, p = 0.026). Most of the isolates belonged to ST type 59, which accounted for 46.8%, followed by ST1 (7/47, 14.9%) and ST910 (5/47, 10.6%). The clone of ST59‐MRSA‐IV with t437 was the most prevalent one. The multiresistant rate of these strains was 93.6%.
Conclusion: The most common disease of CA‐MRSA SSTIs was impetigo, and PVL‐positive abscess was associated with incision and drainage. ST59‐MRSA‐IV with t437 was the most prevalent clone, and the multiresistant rate was high in Chinese children.
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