The transmissibility estimation of influenza with early stage data of small-scale outbreaks in Changsha, China, 2005–2013

SUMMARYHundreds of small-scale influenza outbreaks in schools are reported in mainland China every year, leading to a heavy disease burden which seriously impacts the operation of affected schools. Knowing the transmissibility of each outbreak in the early stage has become a major concern for public health policy-makers and primary healthcare providers. In this study, we collected all the small-scale outbreaks in Changsha (a large city in south central China with ~7·04 million population) from January 2005 to December 2013. Four simple and popularly used models were employed to calculate the reproduction number (R) of these outbreaks. Given that the duration of a generation interval Tc = 2·7 and the standard deviation (s.d.)σ = 1·1, the mean R estimated by an epidemic model, normal distribution and delta distribution were 2·51 (s.d. = 0·73), 4·11 (s.d. = 2·20) and 5·88 (s.d. = 5·00), respectively. When Tc = 2·9 and σ = 1·4, the mean R estimated by the three models were 2·62 (s.d. = 0·78), 4·72 (s.d. = 2·82) and 6·86 (s.d. = 6·34), respectively. The mean R estimated by gamma distribution was 4·32 (s.d. = 2·47). We found that the values of R in small-scale outbreaks in schools were higher than in large-scale outbreaks in a neighbourhood, city or province. Normal distribution, delta distribution, and gamma distribution models seem to more easily overestimate the R of influenza outbreaks compared to the epidemic model.

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Conservation status of the Sichuan Hill-partridge Arborophila rufipectus in China

Bird Conservation International ◽

10.1017/s0959270900002112 ◽

1998 ◽

Vol 8 (4) ◽

pp. 349-359 ◽

Cited By ~ 10

Author(s):

Dai Bo ◽

Simon D. Dowell ◽

Rodney P. Martins ◽

Robert S. R. Williams

Keyword(s):

Conservation Status ◽

Central China ◽

Primary Forest ◽

Density Estimates ◽

Broadleaf Forest ◽

Field Surveys ◽

Forestry Practices ◽

South Central ◽

Line Transects ◽

The Mean

SummaryThe critically endangered Sichuan Hill-partridge Arborophila rufipectus occupies a restricted range in south-central China. Field surveys within this range were undertaken using line transects in 1996 and 1997. Calling males were recorded from nine subtropical forest tracts within an area totalling 1,793 km2 and consisting of primary, natural secondary and replanted broadleaf forest between 1,100 and 2,235 m elevation. The only sightings obtained were in primary forest. The mean density of calling males estimated from data collected during transect surveys was 0.48 ± 0.06 and 0.24 ± 0.16 calling birds km−2 in 1996 and 1997 respectively. There was no difference in density estimates for calling males between primary forest and secondary/replanted broadleaf forest. The principal threat to the continued survival of the species is clear-felling of primary forest, but clear-felled areas are often replanted with native broadleaf trees and records of Sichuan Hill-partridge calls in such plantations offers hope for its future survival. Forest management should be modified to make forestry practices more sympathetic to the conservation of the Sichuan Hill-partridge.

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Structural characteristics and niches of dominant tree populations in Tetracentron sinense communities: implications for conservation

Botanical Sciences ◽

10.17129/botsci.1531 ◽

2018 ◽

Vol 96 (2) ◽

pp. 157 ◽

Cited By ~ 1

Author(s):

Zhongqiong Tian ◽

Huaichun Li ◽

Wenying Li ◽

Xiaohong Gan ◽

Xuemei Zhang ◽

...

Keyword(s):

Early Stage ◽

Structural Characteristics ◽

Central China ◽

Interspecies Interactions ◽

Importance Value ◽

The North ◽

South Central ◽

The Status ◽

Study Sites ◽

Tetracentron Sinense

Background: Tetracentron sinense Oliv., is an endangered, broad-leaved tree distributed in south-central China. Structural characteristics of the community and dominant tree population niches in T. sinense communities are currently unclear.Questions: (1) What is the status of T. sinense populations in the community? (2) What are the interspecies interactions between T. sinense populations and its associated species.Study sites and dates: T. sinense communities in Meigu Dafengding Nature Reserve in southwest China in 2014.Methods: Six sites of 400 m2 were studied for importance value, special diversity, niche breadth, and overlap of dominant tree populations.Results: There were 80 species, 67 genera, and 41 families of vascular plants. Sixty-one genera of seed plants in T. sinense communities were classified into 9 types. The North Temperate genus was the largest, accounting for 44.26 %. Species richness, species diversity, and evenness indexes were all low. There were 6 dominant tree populations in T. sinense communities, and the importance values and niche breadths of T. sinense populations were significantly higher than other species. Horizontal niche overlaps between T. sinense and Pterocarya stenoptera, Acer pictum subsp. mono, and Cercidiphyllum japonicum were high; the vertical niche overlaps between T. sinense and these species were all greater than 0.7.Conclusions: T. sinense communities have North Temperate character, and are immature and unstable communities, still in the early stage of succession. T. sinense is the edificator tree in the communities. A high similarity of habitat demand and strong interspecific competition for light exist between T. sinense and its associated trees.

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Quantification of small-scale heterogeneity in aquatic aminopeptidase activity

Aquatic Microbial Ecology ◽

10.3354/ame01930 ◽

2020 ◽

Vol 84 ◽

pp. 127-140

Author(s):

BM Gaas ◽

JW Ammerman

Keyword(s):

Chlorophyll Fluorescence ◽

Leucine Aminopeptidase ◽

Hudson River ◽

Aminopeptidase Activity ◽

Small Scale ◽

Analysis Instrument ◽

Sequential Samples ◽

Degree Of Confidence ◽

The Mean ◽

Hydrolysis Of

Leucine aminopeptidase (LAP) is one of the enzymes involved in the hydrolysis of peptides, and is sometimes used to indicate potential nitrogen limitation in microbes. Small-scale variability has the potential to confound interpretation of underlying patterns in LAP activity in time or space. An automated flow-injection analysis instrument was used to address the small-scale variability of LAP activity within contiguous regions of the Hudson River plume (New Jersey, USA). LAP activity had a coefficient of variation (CV) of ca. 0.5 with occasional values above 1.0. The mean CVs for other biological parameters—chlorophyll fluorescence and nitrate concentration—were similar, and were much lower for salinity. LAP activity changed by an average of 35 nmol l-1 h-1 at different salinities, and variations in LAP activity were higher crossing region boundaries than within a region. Differences in LAP activity were ±100 nmol l-1 h-1 between sequential samples spaced <10 m apart. Variogram analysis indicated an inherent spatial variability of 52 nmol l-1 h-1 throughout the study area. Large changes in LAP activity were often associated with small changes in salinity and chlorophyll fluorescence, and were sensitive to the sampling frequency. This study concludes that LAP measurements in a sample could realistically be expected to range from zero to twice the average, and changes between areas or times should be at least 2-fold to have some degree of confidence that apparent patterns (or lack thereof) in activity are real.

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Limit tolerances for sums of measurement errors

Geodesy and Cartography ◽

10.22389/0016-7126-2017-934-4-59-62 ◽

2018 ◽

Vol 934 (4) ◽

pp. 59-62

Author(s):

V.I. Salnikov

Keyword(s):

Normal Distribution ◽

Mean Square Error ◽

Gaussian Distribution ◽

Measurement Errors ◽

Theory And Practice ◽

Mean Square ◽

The Mean ◽

Limiting Values ◽

Limiting Value

The question of calculating the limiting values of residuals in geodesic constructions is considered in the case when the limiting value for measurement errors is assumed equal to 3m, ie ∆рred = 3m, where m is the mean square error of the measurement. Larger errors are rejected. At present, the limiting value for the residual is calculated by the formula 3m√n, where n is the number of measurements. The article draws attention to two contradictions between theory and practice arising from the use of this formula. First, the formula is derived from the classical law of the normal Gaussian distribution, and it is applied to the truncated law of the normal distribution. And, secondly, as shown in [1], when ∆рred = 2m, the sums of errors naturally take the value equal to ?pred, after which the number of errors in the sum starts anew. This article establishes its validity for ∆рred = 3m. A table of comparative values of the tolerances valid and recommended for more stringent ones is given. The article gives a graph of applied and recommended tolerances for ∆рred = 3m.

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A New Identification Method Reveals the Resistance of an Extensive-Source Radish Collection to Plasmodiophora brassicae Race 4

Agronomy ◽

10.3390/agronomy11040792 ◽

2021 ◽

Vol 11 (4) ◽

pp. 792

Author(s):

Haohui Yang ◽

Yuxiang Yuan ◽

Xiaochun Wei ◽

Xiaohui Zhang ◽

Haiping Wang ◽

...

Keyword(s):

Plasmodiophora Brassicae ◽

Central China ◽

Clubroot Disease ◽

Cruciferous Vegetable ◽

Inoculation Methods ◽

Identification Method ◽

South Central ◽

Disease Occurrence ◽

Resistant Varieties ◽

The Stability

Raphanus sativus, an important cruciferous vegetable, has been increasingly affected by clubroot disease. Establishing a stable and accurate resistance identification method for screening resistant germplasms is urgently needed in radish. In this study, the influence of inoculum concentration, inoculation methods, and pH of the substrate on disease occurrence was studied. The result showed that the disease index (DI) was highest at 2 × 108 spores/mL, the efficiency of two-stage combined inoculation methods was higher than others, and pH 6.5 was favorable for the infection of P. brassicae. By using this new method, DIs of 349 radish germplasms varying from 0.00 to 97.04, presented significantly different levels of resistance. Analysis showed that 85.06% germplasms from China were susceptible to P. brassicae, whilst 28 accessions were resistant and mainly distributed in east, southwest, northwest, and south-central China. Most of the exotic germplasms were resistant. Repeated experiments verified the stability and reliability of the method and the identity of germplasm resistance. In total, 13 immune, 5 highly resistant and 21 resistant radish accessions were identified. This study provides an original clubroot-tolerance evaluation technology and valuable materials for the development of broad-spectrum resistant varieties for sustainable clubroot management in radish and other cruciferous crops.

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Quantification of Measurement and Model Effects in Monopile Foundation Scour Protection Experiments

Journal of Marine Science and Engineering ◽

10.3390/jmse9060585 ◽

2021 ◽

Vol 9 (6) ◽

pp. 585

Author(s):

Minghao Wu ◽

Leen De Vos ◽

Carlos Emilio Arboleda Chavez ◽

Vasiliki Stratigaki ◽

Maximilian Streicher ◽

...

Keyword(s):

Standard Deviation ◽

Flow Field ◽

Three Dimensional ◽

Small Scale ◽

Maximum Wave Height ◽

Chaotic Flow ◽

The Mean ◽

Scour Protection ◽

Damage Number ◽

Measurement Effects

The present work introduces an analysis of the measurement and model effects that exist in monopile scour protection experiments with repeated small scale tests. The damage erosion is calculated using the three dimensional global damage number S3D and subarea damage number S3D,i. Results show that the standard deviation of the global damage number σ(S3D)=0.257 and is approximately 20% of the mean S3D, and the standard deviation of the subarea damage number σ(S3D,i)=0.42 which can be up to 33% of the mean S3D. The irreproducible maximum wave height, chaotic flow field and non-repeatable armour layer construction are regarded as the main reasons for the occurrence of strong model effects. The measurement effects are limited to σ(S3D)=0.039 and σ(S3D,i)=0.083, which are minor compared to the model effects.

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The Growth of Leaf Lettuce and Bacterial Communities in a Closed Aquaponics System with Catfish

Horticulturae ◽

10.3390/horticulturae7080222 ◽

2021 ◽

Vol 7 (8) ◽

pp. 222

Author(s):

Kenji Yamane ◽

Yuuki Kimura ◽

Keita Takahashi ◽

Isamu Maeda ◽

Masayuki Iigo ◽

...

Keyword(s):

Plant Growth ◽

Early Stage ◽

Amplicon Sequencing ◽

Small Scale ◽

Rrna Gene ◽

Culture Solution ◽

Beneficial Effects ◽

Sustainable Cultivation ◽

Microbial Groups ◽

Production Period

Aquaponics is a circulating and sustainable system that combines aquaculture and hydroponics and forms a symbiotic relationship between fish, plants, and microorganisms. We hypothesized that feed alone could support plant growth, but the symbiosis with fish adds some beneficial effects on plant growth in aquaponics. In this study, we created three closed culture systems, namely, aquaponics, hydroponics without nitrogen (N) and phosphorus (P), and aquaculture, and added the same amount of feed containing N and P to all the treatments in order to test the hypothesis. Accumulation of NO3− and PO43− was alleviated in aquaponics and hydroponics as a result of plant uptake. Lettuce plants grown in aquaponics grew vigorously until 2 weeks and contained a constant level of N in plants throughout the production period, whereas those in hydroponics grew slowly in the early stage and then vigorously after 2 weeks with a late increment of N concentration. These results suggest that catfish help with the faster decomposition of the feed, but, in hydroponics, feed can be slowly dissolved and decomposed owing to the absence of the fish. The bacterial community structures of the culture solution were investigated using 16S rRNA gene amplicon sequencing. At the class level, Actinobacteria, Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria were the major microbial groups in the solutions. Aquaponics prevented the pollution of tank solution and maintained a higher water quality compared with hydroponics and aquaculture, suggesting that aquaponics is a more sustainable cultivation system even in a small-scale system.

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Patterns of Sequelae in Women with a History of Localized Breast Cancer: Results from the French VICAN Survey

Cancers ◽

10.3390/cancers13051161 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1161

Author(s):

Lidia Delrieu ◽

Liacine Bouaoun ◽

Douae El Fatouhi ◽

Elise Dumas ◽

Anne-Deborah Bouhnik ◽

...

Keyword(s):

Breast Cancer ◽

Latent Class ◽

Early Stage ◽

Current Analysis ◽

Functional Pain ◽

Cognitive Sequelae ◽

History Of ◽

The Mean ◽

Study Participants ◽

Changes Over Time

Breast cancer (BC) remains complex for women both physically and psychologically. The objectives of this study were to (1) assess the evolution of the main sequelae and treatment two and five years after diagnosis in women with early-stage breast cancer, (2) explore patterns of sequelae associated with given sociodemographic, clinical, and lifestyle factors. The current analysis was based on 654 localized BC patients enrolled in the French nationwide longitudinal survey “vie après cancer” VICAN (January–June 2010). Information about study participants was collected at enrollment, two and five years after diagnosis. Changes over time of the main sequelae were analyzed and latent class analysis was performed to identify patterns of sequelae related to BC five years after diagnosis. The mean age (±SD) of study participants at inclusion was 49.7 (±10.5) years old. Six main classes of sequelae were identified two years and five years post-diagnosis (functional, pain, esthetic, fatigue, psychological, and gynecological). A significant decrease was observed for fatigue (p = 0.03) and an increase in cognitive sequelae was reported (p = 0.03). Two latent classes were identified—functional and esthetic patterns. Substantial sequelae remain up to five years after BC diagnosis. Changes in patient care pathways are needed to identify BC patients at a high risk.

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A hospital-based study on clinical data, demographic data and visual function of keratoconus patients in Central China

Scientific Reports ◽

10.1038/s41598-021-87291-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kaili Yang ◽

Liyan Xu ◽

Qi Fan ◽

Yuwei Gu ◽

Bo Zhang ◽

...

Keyword(s):

Clinical Data ◽

Rural Areas ◽

Visual Function ◽

Urban Areas ◽

Demographic Data ◽

Corneal Thickness ◽

Positive Family History ◽

Education Level ◽

Central China ◽

The Mean

AbstractChina is a populous country but lacks epidemiological data on keratoconus (KC). The present study aimed to investigate the clinical data, demographic data, and visual function (VF) data of KC patients in Central China. A total of 524 KC eyes in 307 KC patients (217 bilateral and 90 unilateral) from Henan Eye Hospital were included in the current study. Demographic and VF data were assessed with questionnaires administered by well-trained staff during face-to-face interviews. Visual acuity value was examined by a qualified optometrist, and the clinical data were measured by professional clinicians. The distributions of sex, residence and education level of KC patients were compared by Chi-square tests, and the ratios of people wearing glasses and rigid gas permeable (RGP) lenses were compared by McNemar tests. General linear models/Chi-squared tests were used to compare the clinical and demographic data according to KC severity. Spearman’s correlation analysis was used to test the associations between the data and KC severity. The mean age at diagnosis was 20.98 ± 6.06 years, and males had a higher ratio of KC than females (P < 0.001). Patients in rural areas had a higher rate of KC than those in urban areas (P = 0.039), and the proportion of KC patients with a higher education level (above high school) was high (P < 0.001). A total of 68.40% of the patients reported eye rubbing and 3.52% had a positive family history. The percentage of people wearing glasses was higher than that of patients wearing RGP lenses (P < 0.001). The total VF score of KC patients was 69.35 ± 15.25. The thinnest corneal thickness (TCT) and stiffness parameter at the first applanation (SP-A1) values were inversely correlated with KC severity (P < 0.05). The mean, steep, and max keratometry (Km, Ks and Kmax) values, the RGP lens use and keratoplasty were positively correlated with KC severity (all P < 0.05). The total VF score of the eye with better VA decreased as the severity increased (r = − 0.21, P = 0.002). The present study comprehensively describes various associated features of KC patients from a tertiary hospital in Central China, providing a reference for understanding the characteristics of KC patients in China.

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Subcritical Transmission in the Early Stage of COVID-19 in Korea

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18031265 ◽

2021 ◽

Vol 18 (3) ◽

pp. 1265

Author(s):

Yong Sul Won ◽

Jong-Hoon Kim ◽

Chi Young Ahn ◽

Hyojung Lee

Keyword(s):

Incubation Period ◽

Early Stage ◽

Probability Distributions ◽

Likelihood Estimation ◽

Contact Tracing ◽

Statistical Characterization ◽

Serial Interval ◽

Imported Cases ◽

The Mean ◽

Reporting Delays

While the coronavirus disease 2019 (COVID-19) outbreak has been ongoing in Korea since January 2020, there were limited transmissions during the early stages of the outbreak. In the present study, we aimed to provide a statistical characterization of COVID-19 transmissions that led to this small outbreak. We collated the individual data of the first 28 confirmed cases reported from 20 January to 10 February 2020. We estimated key epidemiological parameters such as reporting delay (i.e., time from symptom onset to confirmation), incubation period, and serial interval by fitting probability distributions to the data based on the maximum likelihood estimation. We also estimated the basic reproduction number (R0) using the renewal equation, which allows for the transmissibility to differ between imported and locally transmitted cases. There were 16 imported and 12 locally transmitted cases, and secondary transmissions per case were higher for the imported cases than the locally transmitted cases (nine vs. three cases). The mean reporting delays were estimated to be 6.76 days (95% CI: 4.53, 9.28) and 2.57 days (95% CI: 1.57, 4.23) for imported and locally transmitted cases, respectively. The mean incubation period was estimated to be 5.53 days (95% CI: 3.98, 8.09) and was shorter than the mean serial interval of 6.45 days (95% CI: 4.32, 9.65). The R0 was estimated to be 0.40 (95% CI: 0.16, 0.99), accounting for the local and imported cases. The fewer secondary cases and shorter reporting delays for the locally transmitted cases suggest that contact tracing of imported cases was effective at reducing further transmissions, which helped to keep R0 below one and the overall transmissions small.

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