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Schizophrenia has been primarily conceptualized as a disorder of high-order cognitive functions with deficits in executive brain regions. Yet due to the increasing reports of early sensory processing deficit, recent models focus more on the developmental effects of impaired sensory process on high-order functions. The present study examined whether this pathological interaction relates to an overarching system-level imbalance, specifically a disruption in macroscale hierarchy affecting integration and segregation of unimodal and transmodal networks.
We applied a novel combination of connectome gradient and stepwise connectivity analysis to resting-state fMRI to characterize the sensorimotor-to-transmodal cortical hierarchy organization (96 patients v. 122 controls).
We demonstrated compression of the cortical hierarchy organization in schizophrenia, with a prominent compression from the sensorimotor region and a less prominent compression from the frontal−parietal region, resulting in a diminished separation between sensory and fronto-parietal cognitive systems. Further analyses suggested reduced differentiation related to atypical functional connectome transition from unimodal to transmodal brain areas. Specifically, we found hypo-connectivity within unimodal regions and hyper-connectivity between unimodal regions and fronto-parietal and ventral attention regions along the classical sensation-to-cognition continuum (voxel-level corrected, p < 0.05).
The compression of cortical hierarchy organization represents a novel and integrative system-level substrate underlying the pathological interaction of early sensory and cognitive function in schizophrenia. This abnormal cortical hierarchy organization suggests cascading impairments from the disruption of the somatosensory−motor system and inefficient integration of bottom-up sensory information with attentional demands and executive control processes partially account for high-level cognitive deficits characteristic of schizophrenia.
Human papillomavirus (HPV) has been confirmed as the causative agent for cervical cancer. In this study, a total of 301 880 women were recruited from four different regions of Western China, with 301 880 exfoliated cervical cell samples collected from women for DNA isolation and purification. The HPV genotype was tested by polymerase chain reaction. The overall HPV prevalence rate, high-risk (HR) HPV infection rate, low-risk (LR) HPV infection rate and mixed HPV infection rate was 18.24%, 79.14%, 12.56% and 8.30%, respectively. The four most common HR HPV subtypes were HPV-52, 16, 58 and 53, which accounted for 20.49%, 19.93%, 14.54% and 10.01%, respectively. In LR HPV genotype, HPV-6 ranked the highest (28.17%), followed by HPV-81 (9.09%) and HPV-11 (3.78%). HPV genotype subgroup analysis also showed that single-type infection was the most common (77.26%) among HPV-positive individuals. Among multi-infection genotypes, double infection was the most common with frequencies of 76.04%. The overall prevalence of HPV is high in Western China, whose distribution demonstrates different patterns across different ages and regions. Viral genotypes HPV 53, 6 were frequently detected in this population, which is worth of significant clinical attention.
The purpose of the current study was to investigate associations between spicy food intake and serum lipids levels in Chinese rural population.
Information on spicy food flavour and intake frequency was obtained using a two-item questionnaire survey. Dietary data were collected using a validated thirteen-item FFQ. Fasting blood samples were collected and measured for total cholesterol (TC), TAG, HDL-cholesterol and LDL-cholesterol. Multivariate linear and logistic regression models were employed to examine the relationship between spicy food and serum lipids levels according to the spicy food flavour and intake frequency, respectively.
A cross-sectional study in Henan Province.
38 238 participants aged 18–79 years old.
Spicy flavour and intake frequency were consistently associated with decreased TC and non-HDL-cholesterol levels but mildly associated with elevated TAG levels. Each level increment in spicy flavour was inversely associated with high TC (OR: 0·91; 95 % CI 0·88, 0·93) and high non-HDL-cholesterol (OR: 0·88; 95 % CI 0·85, 0·91) but positively associated with high TAG (OR: 1·04; 95 % CI 1·01, 1·07). Similarly, 1-d increment in spicy food intake frequency was also inversely associated with high TC (OR: 0·92; 95 % CI 0·91, 0·94) and high non-HDL-cholesterol (OR: 0·91; 95 % CI 0·89, 0·93) but positively associated with high TAG (OR: 1·04; 95 % CI 1·02, 1·06).
Spicy food intake was mildly associated with increased risk of abnormal TAG level, significantly associated with decreased risk of abnormal TC and non-HDL levels. Spicy food intake may be contribute to the management of lipid levels.
Bacterial dysentery (BD) brings a major disease burden to developing countries. Exploring the influence of temperature and its interaction with other meteorological factors on BD is significant for the prevention and early warning of BD in the context of climate change. Daily BD cases and meteorological data from 2008 to 2018 were collected in all nine prefecture-level cities in Jilin Province. A one-stage province-level model and a two-stage city-specific multivariate meta-pooled level distributed lag non-linear model were established to explore the correlation between temperature and BD, then the weather-stratified generalised additive model was used to test the interaction. During the study period, a total of 26 971 cases of BD were developed. The one-stage and two-stage cumulative dose-response ‘J’ curves overlapped, and results showed a positive correlation between temperature and BD with a 1–6 days lag effect. Age group ⩾5 years was found to be more sensitive to the effects. Moreover, there was a significant interaction between temperature, humidity and precipitation (P = 0.004, 0.002, respectively) on BD under high temperature (>0 °C), reminding residents and policymakers to pay attention to the prevention of BD in situations with both high temperature and humidity, high temperature and precipitation during the temperate monsoon climate.
Echinococcus granulosus sensu lato has complex defence mechanisms that protect it from the anti-parasitic immune response for long periods. Echinococcus granulosus cyst fluid (EgCF) is involved in the immune escape. Nevertheless, whether and how EgCF modulates the inflammatory response in macrophages remains poorly understood. Here, real-time polymerase chain reaction and enzyme-linked immunosorbent assay revealed that EgCF could markedly attenuate the lipopolysaccharide (LPS)-induced production of pro-inflammatory factors including tumour necrosis factor-α, interleukin (IL)-12 and IL-6 but increase the expression of IL-10 at mRNA and protein levels in mouse peritoneal macrophages and RAW 264.7 cells. Mechanically, western blotting and immunofluorescence assay showed that EgCF abolished the activation of nuclear factor (NF)-κB p65, p38 mitogen-activated protein kinase (MAPK) and ERK1/2 signalling pathways by LPS stimulation in mouse macrophages. EgCF's anti-inflammatory role was at least partly contributed by promoting proteasomal degradation of the critical adaptor TRAF6. Moreover, the EgCF-promoted anti-inflammatory response and TRAF6 proteasomal degradation were conserved in human THP-1 macrophages. These findings collectively reveal a novel mechanism by which EgCF suppresses inflammatory responses by inhibiting TRAF6 and the downstream activation of NF-κB and MAPK signalling in both human and mouse macrophages, providing new insights into the molecular mechanisms underlying the E. granulosus-induced immune evasion.
To clarify nutrient supplementation usage and primary source of information among pregnant women in China.
This cross-sectional study used information on nutrient supplementation and primary source of information collected via face-to-face interviews. Data on the usage of folic acid, calcium/vitamin D, iron, vitamins, docosahexaenoic acid, and other dietary supplements were collected. Primary source of information were categorized as family/relatives, friends/co-workers, the Internet, books/magazines, television/radio, doctors, other people, and oneself.
Maternal and Child Health Hospital in Chengdu, China.
1081 Chinese pregnant women aged ≥ 20 years with singleton pregnancies.
In all three trimesters of pregnancy, usage was highest and most stable for folic acid (81.7%), followed by vitamins (vitamin A, B-group vitamins, vitamin C, and multivitamins; 75.0%), whereas calcium/vitamin D (51.4%) and iron (18.1%) usage was low, potentially indicating a deficiency risk. All supplementation usage percentages increased with pregnancy duration (p < 0.05). Notably, approximately 10% of the pregnant women in our study did not use any nutrient supplementation, and this was especially common in early pregnancy. More than 50% of the women reported getting information on nutrient supplementation from family members, and about 30% reported getting this information from doctors.
Among pregnant women in China, awareness about nutrient supplementation increases as the pregnancy progresses, but some types of nutrient supplementation (such as calcium/vitamin D and iron) remain at low levels. It is necessary to pay more attention to the health education of pregnant women in China, and the influence of family members should be emphasized.
We carry out direct numerical simulations of turbulent Rayleigh–Bénard convection in a square box with rough conducting plates over the Rayleigh number range $10^7\leqslant Ra\leqslant 10^9$ and the Prandtl number range $0.01\leqslant Pr\leqslant 100$. In Zhang et al. (J. Fluid Mech., vol. 836, 2018, R2), it was reported that while the measured Nusselt number $Nu$ is enhanced at large roughness height $h$, the global heat transport is reduced at small $h$. The division between the two regimes yields a critical roughness height $h_c$, and we now focus on the effects of the Prandtl number ($Pr$) on $h_c$. Based on the variations of $h_c$, we identify three regimes for $h_c(Pr)$. For low $Pr$, thermal boundary layers become thinner with increasing $Pr$. This makes the boundary layers easier to be disrupted by rough elements, leading to the decrease of $h_c$ with increasing $Pr$. For moderate $Pr$, the corner-flow rolls become much more pronounced and suppress the global heat transport via the competition between the corner-flow rolls and the large-scale circulation (LSC). As a consequence, $h_c$ increases with increasing $Pr$ due to the intensification of the corner–LSC competition. For high $Pr$, the convective flow transitions to the plume-controlled regime. As the rough elements trigger much stronger and more frequent plume emissions, $h_c$ again decreases with increasing $Pr$.
Understanding the extent of aerosol-based transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is important for tailoring interventions for control of the coronavirus disease 2019 (COVID-19) pandemic. Multiple studies have reported the detection of SARS-CoV-2 nucleic acid in air samples, but only one study has successfully recovered viable virus, although it is limited by its small sample size.
We aimed to determine the extent of shedding of viable SARS-CoV-2 in respiratory aerosols from COVID-19 patients.
In this observational air sampling study, air samples from airborne-infection isolation rooms (AIIRs) and a community isolation facility (CIF) housing COVID-19 patients were collected using a water vapor condensation method into liquid collection media. Samples were tested for presence of SARS-CoV-2 nucleic acid using quantitative real-time polymerase chain reaction (qRT-PCR), and qRT-PCR-positive samples were tested for viability using viral culture.
Samples from 6 (50%) of the 12 sampling cycles in hospital rooms were positive for SARS-CoV-2 RNA, including aerosols ranging from <1 µm to >4 µm in diameter. Of 9 samples from the CIF, 1 was positive via qRT-PCR. Viral RNA concentrations ranged from 179 to 2,738 ORF1ab gene copies per cubic meter of air. Virus cultures were negative after 4 blind passages.
Although SARS-CoV-2 is readily captured in aerosols, virus culture remains challenging despite optimized sampling methodologies to preserve virus viability. Further studies on aerosol-based transmission and control of SARS-CoV-2 are needed.
Linoleic acid (LA) is predominantly essential for poultry. Poultry lacking LA show retarded growth and reduced disease resistance. Intestinal barrier function plays an important role in pigeon squab growth, whereas research on the effects of LA on intestinal health in altrices is scant. Considering that squabs are fed by their parents, the study aimed to explore the effects of maternal dietary LA on intestinal morphology, tight junction proteins, immune cytokines and microbial flora in squabs. A completely randomised design with a control group, 1 % LA supplementation group, 2 % LA supplementation group and 4 % LA supplementation group was used. Six squabs from each treatment were randomly sampled at 21 d post-hatching. The results indicated that LA supplementation improved intestinal morphology, as reflected by increased villus height, villus area and the ratio of villi to crypts. Also, 1 % LA supplementation elevated the density of goblet cells in the intestine and strengthened tight junctions by up-regulating claudin-3 and occludin gene expression but down-regulating claudin-2 gene expression. Moreover, 1 % LA supplementation reduced the secretion of proinflammatory cytokines and partly increased anti-inflammatory cytokines. The intestinal microbial diversity in the 1 % LA supplementation group was higher than that in the other groups. As beneficial bacteria, Butyrivibrio was the biomarker of 1 % LA supplementation. However, excessive (4 %) LA supplementation led to adverse impacts on intestinal immunity and microbiota. In conclusion, maternal dietary LA might alter intestinal barrier function in pigeon squabs in a dose-dependent manner. Supplementation with 1 % LA was suggested in parental pigeons.
An acute gastroenteritis (AGE) outbreak caused by a norovirus occurred at a hospital in Shanghai, China, was studied for molecular epidemiology, host susceptibility and serological roles. Rectal and environmental swabs, paired serum samples and saliva specimens were collected. Pathogens were detected by real-time polymerase chain reaction and DNA sequencing. Histo-blood group antigens (HBGA) phenotypes of saliva samples and their binding to norovirus protruding proteins were determined by enzyme-linked immunosorbent assay. The HBGA-binding interfaces and the surrounding region were analysed by the MegAlign program of DNAstar 7.1. Twenty-seven individuals in two care units were attacked with AGE at attack rates of 9.02 and 11.68%. Eighteen (78.2%) symptomatic and five (38.4%) asymptomatic individuals were GII.6/b norovirus positive. Saliva-based HBGA phenotyping showed that all symptomatic and asymptomatic cases belonged to A, B, AB or O secretors. Only four (16.7%) out of the 24 tested serum samples showed low blockade activity against HBGA-norovirus binding at the acute phase, whereas 11 (45.8%) samples at the convalescence stage showed seroconversion of such blockade. Specific blockade antibody in the population played an essential role in this norovirus epidemic. A wide HBGA-binding spectrum of GII.6 supports a need for continuous health attention and surveillance in different settings.
Manure and chemical fertilizers have different effects on soil properties, the nitrogen cycle, and crop yield. This study aimed to investigate the effects of different fertilizer applications under the same N input on soil physicochemical properties and soil bacterial communities and to explain the contributions of soil properties to grain yield. Manure substitution of chemical fertilizer was conducted in leaching monitoring systems. The study began in 2009 and sampling was carried out in 2014 and 2016. Three fertilizer treatments with the same total N, P, and K application rates and one control treatment were designed as follows: (1) CK, without nitrogen fertilizer; (2) 100%U, whole nitrogen coming from urea; (3) 100%M, whole nitrogen coming from composted cattle manure; and (4) 50%U + 50%M, half nitrogen from composted cattle manure and half nitrogen from urea. Soil organic carbon (SOC) content was positively correlated with total N (TN), NO3−–N, and NH4+–N contents, the mean weight diameter of soil aggregates, and the Shannon diversity index of bacteria, whereas SOC content was not significantly correlated with grain yield. NO3−–N content was positively correlated with grain yield. Substituting half the amount of chemical fertilizer with manure as a nitrogen source improved soil stability, increased bacterial diversity, and enhanced nitrogen supply, while reducing nitrogen loss from ammonia volatilization and nitrogen leaching. Substituting half the amount of chemical fertilizer with manure as a nitrogen source was a more sustainable way to increase grain yield through a sustainable nitrate supply and to reduce N loss.
With the aim of optimizing the traditional construction process of a fiber-reinforced lattice structure, the present study modified a previously proposed technique called “truss stacking and node gluing.” To explicitly investigate the structural compressive properties (compressive strength and compressive modulus under the flat pressure), the geometrical parameters, material properties, and topological configuration were examined in detail. Additionally, the present study conducted the relevant theoretical analyses to predict the possible destruction modes and compressive properties. All the samples were tested with a universal testing machine at a rate of 2 mm/min using the ASTM-C365 standard. The results showed that compressive properties are positively related to the relative density and negatively related to the aspect ratio. It was also found that the compressive performance for different materials was in the following order (from good to bad): cotton-fiber reinforced epoxy composite (CREC), jute-fiber reinforced epoxy composite (JREC), and nylon-fiber reinforced epoxy composite (NREC). Furthermore, the mixed topological structure performed as well as the square structure, and they both overmatched the diamond structure. Lastly, the accuracy of the theoretical analysis was evaluated by comparing the theoretical values and the experimental values.
Common vetch (Vicia sativa) is an important forage and green manure crop that is widely cultivated around the world. However, the large number of subspecies and accessions of common vetch has made taxonomic research on this species difficult. Pollen morphology data can provide important evidence in the study of plant phylogeny. Therefore, in this research, light microscopy and scanning electron microscopy were used to observe seven morphological traits of pollens from 22 common vetch accessions, and residual maximum likelihood and pattern analysis was conducted. The results showed that the pollen grains of the 22 accessions were all monad pollen and the polar view revealed three-lobed circular and triangular shapes, while the equatorial view mainly revealed an oblate shape; only one accession showed an oblate spherical shape. All accessions were 3-zonocolporate and the colpus length extended close to the poles. The polar axis length was (19.39 ± 0.97)–(42.12 ± 0.76) μm and the equatorial axis length was (35.97 ± 1.27)–(45.25 ± 0.81) μm. We found that qualitative traits of pollen shape, aperture polar view and ornamentation were highly stable. Among them, polar axis length, equatorial axis length and colpus length and width had significant differences among the accessions. The ratios of the equatorial and polar axes had significant differences among the subspecies. This trait information could be used for the classification and identification of common vetch accessions and subspecies.
Cysticercosis caused by the metacestode larval stage of Taenia hydatigena formerly referred to as Cysticercus tenuicollis is a disease of veterinary importance that constitutes a significant threat to livestock production worldwide, especially in endemic regions due to condemnation of visceral organs and mortality rate of infected young animals. While the genetic diversity among parasites is found to be potentially useful in many areas of research including molecular diagnostics, epidemiology and control, that of T. hydatigena across the globe remains poorly understood. In this study, analysis of the mitochondrial DNA (mtDNA) of adult worms and larval stages of T. hydatigena isolated from dogs, sheep and a wild boar in China showed that the population structure consists of two major haplogroups with very high nucleotide substitutions involving synonymous and non-synonymous changes. Compared with other cestodes such as Echinococcus spp., the genetic variation observed between the haplogroups is sufficient for the assignment of major haplotype or genotype division as both groups showed a total of 166 point-mutation differences between the 12 mitochondrial protein-coding gene sequences. Preliminary analysis of a nuclear protein-coding gene (pepck) did not reveal any peculiar changes between both groups which suggests that these variants may only differ in their mitochondrial makeup.
The risk of environmental contamination by severe acute respiratory coronavirus virus 2 (SARS-CoV-2) in the intensive care unit (ICU) is unclear. We evaluated the extent of environmental contamination in the ICU and correlated this with patient and disease factors, including the impact of different ventilatory modalities.
In this observational study, surface environmental samples collected from ICU patient rooms and common areas were tested for SARS-CoV-2 by polymerase chain reaction (PCR). Select samples from the common area were tested by cell culture. Clinical data were collected and correlated to the presence of environmental contamination. Results were compared to historical data from a previous study in general wards.
In total, 200 samples from 20 patient rooms and 75 samples from common areas and the staff pantry were tested. The results showed that 14 rooms had at least 1 site contaminated, with an overall contamination rate of 14% (28 of 200 samples). Environmental contamination was not associated with day of illness, ventilatory mode, aerosol-generating procedures, or viral load. The frequency of environmental contamination was lower in the ICU than in general ward rooms. Eight samples from the common area were positive, though all were negative on cell culture.
Environmental contamination in the ICU was lower than in the general wards. The use of mechanical ventilation or high-flow nasal oxygen was not associated with greater surface contamination, supporting their use and safety from an infection control perspective. Transmission risk via environmental surfaces in the ICUs is likely to be low. Nonetheless, infection control practices should be strictly reinforced, and transmission risk via droplet or airborne spread remains.
The Shuangjianzishan vein-type Ag-Pb-Zn deposit in the southern Great Xing’an Range (GXR), NE China, is hosted in the slate of the Lower Permian Dashizhai Formation intruded by granite porphyry. In this paper, U–Pb zircon ages and bulk-rock and isotope (Sr, Nd, Pb and Hf) compositions are reported to investigate the derivation, evolution and geodynamic setting of this granite porphyry. It is closely associated with Pb-Zn-Ag mineralization in the southern GXR and contains important geological information relating to regional tectonic evolution. Laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS) zircon U–Pb dating yields an emplacement age of 131 ± 1 Ma for the granite porphyry. Bulk-rock analyses show that the Shuangjianzishan granite porphyry is characterized by high Si, Na and K contents but low Mg and Fe contents, and that the enrichment of Zr, Y and Ga suggests an A-type granite affinity. Most of the studied samples have relatively low 87Sr/86Sr values (0.70549–0.70558), with positive ϵNd(t) (0.71–0.88) and ϵHf(t) (4.9–6.9) values. The Sr–Nd isotope modelling results, in combination with the young TDM2 ages of Nd and Hf (850–864 and 668–778 Ma, respectively), reveal that the Shuangjianzishan granite porphyry may be derived from the melting of mantle-derived juvenile component, with minor lower crustal components; this finding is also supported by Pb isotopic compositions. Considering the widespread presence of granitoids with coeval volcanic rocks and regional geology data, we propose that the Shuangjianzishan granite porphyry formed in a post-orogenic extensional environment related to the upwelling of asthenospheric mantle following the closure of the Mongol–Okhotsk Ocean.
To reveal the thermal shock resistance of double-layer thermal barrier coatings (TBCs), two types of TBCs were prepared via atmospheric plasma spraying, i.e., Gd2Zr2O7/yttria-stabilized zirconia (GZ/YSZ) TBCs and La2Zr2O7 (LZ)/YSZ TBCs, respectively. Subsequently, thermal cycling tests of the two TBCs were conducted at 1100 °C and their thermal shock resistance and failure mechanism were comparatively investigated through experiments and the finite element method. The results showed that the thermal shock failure of the two TBCs occurred inside the top ceramic coating. However, the GZ/YSZ TBCs had longer thermal cycling life. It was the mechanical properties of the top ceramic coating, and the thermal stresses arising from the thermal mismatch between the top ceramic coating and the substrate that determined the thermal cycling life of the two TBCs together. Compared with the LZ layer in the LZ/YSZ TBCs, the GZ layer in the GZ/YSZ TBCs had smaller elastic modulus, larger fracture toughness, and smaller thermal stresses, which led to the higher crack propagation resistance and less spallation tendency of the GZ/YSZ TBCs. Therefore, the GZ/YSZ TBCs exhibited superior thermal shock resistance to the LZ/YSZ TBCs.
We explored the genetic architecture of metabolic risk factors of cardiovascular diseases (CVDs) and their clustering in Chinese boys and girls. Seven metabolic traits (body mass index [BMI], waist circumference [WC], systolic blood pressure [SBP], diastolic blood pressure [DBP], total cholesterol [TC], triglyceride [TG], and uric acid [UA]) were measured in a sample of 1016 twins between 8 and 17 years of age, recruited from the Qingdao Twin Registry. Cholesky, independent pathway, and common pathway models were used to identify the latent genetic structure behind the clustering of these metabolic traits. Genetic architecture of these metabolic traits was largely similar in boys and girls. The highest heritability was found for BMI (a2 = 0.63) in boys and TC (a2 = .69) in girls. Three heritable factors, adiposity (BMI and WC), blood pressure (SBP and DBP), and metabolite factors (TC, TG, and UA), which formed one higher-order latent phenotype, were identified. Latent genetic, common environmental, and unique environmental factors indirectly impacted the three factors through one single latent factor. Our results suggest that there is one latent factor influencing several metabolic traits, which are known risk factors of CVDs in young Chinese twins. Latent genetic, common environmental, and unique environmental factors indirectly imposed on them. These results inform strategies for gene pleiotropic discovery and intervening of CVD risk factors during childhood and adolescence.
Rice (Oryza sativa L.) is the primary staple crop in Taiwan, and it can be grown twice a year. The prevalent subspecies grown in Taiwan is Japonica, and a transplanting system is used for rice production. Although the transplanting system is known for efficient weed control at the seedling stage, weedy red rice (WRR, O. sativa f. spontanea) infestation is progressively being reported. Fieldwork and previous studies have suggested that WRR infestation in Taiwan is probably related to growers’ operating practices and their perception of WRR. However, no data are available for a detailed investigation. The present study aimed to collect data on rice growers’ backgrounds, farming practices, and perceptions of WRR to quantify and characterize the patterns of farming operations for rice growers in Taiwan and to investigate factors contributing to WRR infestation. We collected 408 questionnaires completed by rice growers from 17 counties covering all rice production regions in Taiwan. The growers’ median age was 51 to 60 yr, and 75% of respondents had paddies from 0.25 to 2.75 ha in size, which corresponded with nationwide data for farmers’ backgrounds. In general, growers applied similar farming practices for both cropping seasons. Most respondents did not notice WRR infestation or consider it to be a problem: only 9.8% noticed a moderate to severe infestation of WRR in their fields. The major perceived causes of WRR infestation was seed impurity (55.1%) or cultivar degeneration (18.6%). Correlation analysis and farming patterns estimated with a nonnegative matrix factorization algorithm showed that WRR contamination rate was due to the use of dry or wet tillage. The present study provides the first quantitative and qualitative evidence of rice production practices and growers’ perceptions of WRR infestation in Taiwan.