627 research outputs found
Structure of southeastern Antarctic Peninsula ice shelves and ice tongues from synthetic aperture radar imagery
Expression of wheat gibberellins 2-oxidase gene induced dwarf or semi-dwarf phenotype in rice
Gibberellins (GAs) are a class of plant hormones that play important roles in diverse aspects during plant growth and development. A series of GA synthesis and metabolism genes have been reported or proved to have essential functions in different plant species, while a small number of GA 2-oxidase genes have been cloned or reported in wheat. Previous studies have provided some important findings on the process of GA biosynthesis and the enzymes involved in its related pathways. These may facilitate understanding of the complicated process underlying GA synthesis and metabolism in wheat. In this study, GA 2-oxidase genes TaGA2ox1-1, TaGA2ox1-2, TaGA2ox1-3, TaGA2ox1-4, TaGA2ox1-5, and TaGA2ox1-6 were identified and further overexpressed in rice plants to investigate their functions in GA biosynthesis and signaling pathway. Results showed overexpression of GA 2-oxidase genes in rice disrupted the GA metabolic pathways and induced catalytic responses and regulated other GA biosynthesis and signaling pathway genes, which further leading to GA signaling disorders and diversity in phenotypic changes in rice plants
Hepatitis B virus subgenotype C2 is the most prevalent subgenotype in northeast China
AbstractThe geographical distribution of hepatitis B virus (HBV) subgenotypes and their clinical implications in patients with acute and chronic hepatitis B in the Heilung-kiang province of northeast China were investigated. Nested PCR and multiplex PCR were performed with genotype-specific primers and with subgenotype-specific primers to identify genotypes and subgenotypes from serum samples of 412 HBV infections including 69 with acute self-limited hepatitis (ASH) and 343 with chronic hepatitis (CH). A total of 361 samples were genotyped and 304 were further subgenotyped. The most common HBV genotype was C (93.63%, 338/361), with subgenotype group C2 (83.73%, 283/338) predominating. Genotype B was also found and subgenotype B2 predominated within this genotype. Out of 69 infected patients with ASH, 48 were identified as genotype C and all belonged to subgenotype C2. Of 343 infected patients with CH, 313 were genotyped and 256 were subgenotyped; amongst these, C2 (91.80%, 235/256), B2 (7.42%, 19/256) and mixed subgenotypes B2 and C2 (0.78%, 2/256) were found. In HBV subgenotype C2 infections, ASH had a higher ratio of women than CH patients. These results show that HBV subgenotypes C2 and B2 were found in Heilung-kiang province of northeast China. In ASH and CH groups, the distributions of subgenotypes were coincident with C2, the predominant subgenotype. Analysis of the association between subgenotype and the outcomes of HBV infection was inconclusive in our study
Efficient Agrobacterium tumefaciens -mediated transformation of Malus zumi (Matsumura) Rehd using leaf explant regeneration system
Malus zumi is known as an excellent dwarfing apple rootstock
occurring in natural or arid/semiarid soil or salina. Gene manipulation
of M. zumi through transgenic technology can modify plant feature for
further improvement fruit tree production by grafting the scion on a
transgenic rootstock. Here, we report the establishment of an
efficient, in vitro, shoot regeneration system and Agrobacterium
tumefaciens - mediated transformation from the leaf explants for Malus
zumi (Matsumura) Rehd. Leaf explants were infected with Agrobacterium
strains containing nptII and gus gene. The highest frequency of shoot
regeneration was obtained on MS medium containing 500 mg l-1
Lactalbumin hydrolysate, 30 g l-1 fructose, supplemented with 3.0 mg
l-1 BA, 0.2 mg l-1 NAA.Using fructose instead of sucrose significantly
increases the shoot regeneration and decreases vitrification. This
regeneration procedure was incorporated into an Agrobacterium-mediated
transformation procedure in M. zumi. Kanamycin was an efficient
selective agent for selection. Pre-selection (5 days after
co-cultivation) improved the transformation efficiency. The emergence
of expected bands by PCR analysis and Southern blot in transgenic
plantlets confirmed the transformation of foreign DNA into plant
genome
Spike Timing-Dependent Plasticity in the CA1 Pyramidal Neuron in a Modeled Hippocampal Circuit
Spike timing-dependent plasticity (STDP) plays an important role in sculpting informationstoring circuits in the hippocampus, since motor learning and memory are thought to be
closely linked with this classical plasticity. To further understand the information delivery in
a hippocampus circuit, we build a computational model to study the potential role of linear
changes in the synaptic weight and synaptic number. Several key results have been obtained:
(i) Changes in the synaptic weight and numbers lead to different long-term modification; (ii)
the first paired spiking from two neurons significantly influences the adjusted subsequent
paired spiking; the pre-post spiking pair strengthens the following paired spiking; however,
the post-pre spiking pair depresses the subsequent spiking; (iii) when the synaptic weight and
synaptic numbers are changed, the interval of the first spiking pair may undergo reduction,
and (iv) when we stimulate a stellate neuron weakly or decrease the capacitance of CA1
pyramidal neuron, LTP is more easily produced than LTD; on the contrary, LTD is more easily
produced in an opposite situation; increase in the synaptic numbers can promote activation of
the CA1 pyramidal neuron.Пластичність, залежна від часу генерування піків (spike
timing-dependent plasticity – STDP), відіграє важливу роль
у формуванні нейромереж, що накопичують інформацію
в гіпокампі; вважається, що моторне навчання та пам’ять
тісно пов’язані з пластичністю цього типу. Для глибшого
розуміння процесів передачі інформації в гіпокампальній
нейромережі ми створили комп’ютерну модель, щоб
вивчити потенціальну роль лінійних змін синаптичної ваги
та числа синапсів у таких мережах. Було отримано чотири
основні результати: 1) зміни ваги та числа синапсів можуть
призводити до появи різних феноменів довготривалої
модифікації; 2) перша пара потенціалів дії, генерована
двома нейронами, істотно впливає на характеристики другої
пари піків; генерація пари піків у пре-пост-послідовності
полегшує генерацію наступної пари, тоді як пост-прегенерація пари пригнічує генерацію наступної пари; 3) коли
вага синапсів та їх кількість змінюються, інтервал у першій
парі піків зменшується; 4) коли стимулювати зірчастий
нейрон з невеликою інтенсивністю або зменшити ємність
пірамідного нейрона CA1, легше індукується довготривала
потенціація; у протилежній ситуації легше виникає
довготривала депресія; збільшення числа синапсів полегшує
активацію пірамідного нейрона CA1
Phenotypic blood glutathione concentration and selenium supplementation interactions on meat colour stability and fatty acid concentrations in Merino lambs
The interaction between blood glutathione (GSH) and supplementation of selenium (Se, 2.5 mg/kg diet) on meat colour and fatty acids concentrations was studied. Forty eight Merino lambs selected for high blood GSH (HGSH) or low GSH (LGSH) concentration were used. They were fed individually with or without Se supplement for 8 weeks. There were interactions (P< 0.05) between GSH and Se on the colour stability (as w630 nm/w580 nm ratio) of m. longissimus (LD), m. semimembranosus (SM) and m. semitendinosus. Without Se supplementation the ratio was higher in HGSH than LGSH group. However, the difference was reduced with Se supplement. Polyunsaturated and n-3 fatty acids in SM and LD were higher in HGSH than in LGSH group (P< 0.05), and did not change with Se supplement. Se supplementation increased Se content in LD (P< 0.001) and the lungs (P< 0.05), but had no influence in the heart
Multiple sources of infection and potential endemic characteristics of the large outbreak of dengue in Guangdong in 2014
A large outbreak of dengue, with the most documented cases, occurred in Guangdong China in 2014. Epidemiological studies and phylogenetic analysis of the isolated dengue virus (DENV) showed this outbreak was attributed to multiple sources and caused by at least two genotypes of DENV-1 (Genotypes I and III) and two genotypes of DENV-2 (Cosmopolitan and Asian I Genotypes). A retrospective review and phylogenetic analysis of DENV isolated in Guangdong showed that DENV-1 Genotype I strains were reported continuously during 2004-2014, Genotype III strains were reported during 2009-2014 ; DENV-2 Cosmopolitan and Asian I Genotype strains were reported continuously during 2012-2014. At least 45,171 cases were reported in this outbreak, with 65.9% of the patients in the 21-55-year-old group. A trend toward a decrease in the daily newly emerged cases lagged by approximately 20 days compared with the mosquito density curve. Several epidemiological characteristics of this outbreak and the stably sustained serotypes and genotypes of DENV isolated in Guangdong suggest that Guangdong has been facing a threat of transforming from a dengue epidemic area to an endemic area. The high temperature, drenching rain, rapid urbanization, and pandemic of dengue in Southeast Asia may have contributed to this large outbreak of dengue
Use of traditional and complementary medicine as self-care strategies in community health centers
In China, Community Health Centers (CHCs) are major providers of primary care services, but their potential in empowering patients’ self-management capacity has not been assessed. This study aims to describe self-care practice patterns amongst CHC attendees in urban China.
In this cross-sectional quantitative study, 3360 CHC patients from 6 cities within the Pearl Delta Region were sampled using multistage cluster sampling.
Thirty-seven per cent had used with over-the-counter Chinese herbal medicines (OTC CHMs) in the past year and majority of respondents found OTC CHMs effective. OTC CHMs were more popular amongst those who needed to pay out of pocket for CHC services. Less than 10% used vitamins and minerals, and those with a lower socioeconomic background have a higher propensity to consume. Although doubts on their usefulness are expressed, their use by the vulnerable population may reflect barriers to access to conventional health care, cultural affinity, or a defense against negative consequences of illnesses. About 25% performed physical exercise, but the prevalence is lower amongst women and older people. Taiji seems to be an alternative for these populations with promising effectiveness, but overall only 6% of CHC attendees participated.
These results suggest that CHCs should start initiatives in fostering appropriate use of OTC CHM, vitamins, and minerals. Engaging community pharmacists in guiding safe and effective use of OTC CHM amongst the uninsured is essential given their low accessibility to CHC services. Prescription of Taiji instead of physical exercises to women and older people could be more culturally appropriate, and the possibility of including this as part of the CHC services worth further exploration
Factors associated with adoption of the electronic health record system among primary care physicians
Background: A territory-wide Internet-based electronic patient record allows better patient care in different sectors. The engagement of private physicians is one of the major facilitators for implementation, but there is limited information about the current adoption level of electronic medical record (eMR) among private primary care physicians.
Objective: This survey measured the adoption level, enabling factors, and hindering factors of eMR, among private physicians in Hong Kong. It also evaluated the key functions and the popularity of electronic systems and vendors used by these private practitioners.
Methods: A central registry consisting of 4324 private practitioners was set up. Invitations for self-administered surveys and the completed questionnaires were sent and returned via fax, email, postal mail, and on-site clinic visits. Current users and non-users of eMR system were compared according to their demographic and practice characteristics. Student’s t tests and chi-square tests were used for continuous and categorical variables, respectively.
Results: A total of 524 completed surveys (response rate 524/4405 11.90%) were collected. The proportion of using eMR in private clinics was 79.6% (417/524). When compared with non-users, the eMR users were younger (users: 48.4 years SD 10.6 years vs non-users: 61.7 years SD 10.2 years, P<.001); more were female physicians (users: 80/417, 19.2% vs non-users: 14/107, 13.1%, P=.013); possessed less clinical experience (with more than20 years of practice: users: 261/417, 62.6% vs non-user: 93/107, 86.9%, P<.001); fewer worked under a Health Maintenance Organization (users: 347/417, 83.2% vs non-users: 97/107, 90.7%, P<.001) and more worked with practice partners (users: 126/417, 30.2% vs non-users: 4/107, 3.7%, P<.001). Efficiency (379/417, 90.9%) and reduction of medical errors (229/417, 54.9%) were the major enabling factors, while patient-unfriendliness (58/107, 54.2%) and limited consultation time (54/107, 50.5%) were the most commonly reported hindering factors. The key functions of computer software among eMR users consisted of electronic patient registration system (376/417, 90.2%), drug dispensing system (328/417, 78.7%) and electronic drug labels (296/417, 71.0%). SoftLink Clinic Solution was the most popular vendor (160/417, 38.4%).
Conclusions: These findings identified several physician groups who should be targeted for more assistance on eMR installation and its adoption. Future studies should address the barriers of using Internet-based eMR to enhance its adoption
Two charged strangeonium-like structures observable in the process
Via the Initial Single Pion Emission (ISPE) mechanism, we study the
invariant mass spectrum distribution of . Our calculation indicates there exist a sharp peak
structure () close to the threshold and a broad
structure () near the threshold. In addition, we
also investigate the process due to
the ISPE mechanism, where a sharp peak around the threshold
appears in the invariant mass spectrum distribution. We
suggest to carry out the search for these charged strangeonium-like structures
in future experiment, especially Belle II, Super-B and BESIII.Comment: 7 pages, 5 figures. Accepted by Eur. Phys. J.
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