Food essentialism: Implications for expectations and perceptions of the properties of processed foods

Despite the impact of processed foods on health, sustainability, and food security, consumers vary greatly in expectations about and preferences for processed foods. Essentialism is the lay belief that items in a category share a fundamental and immutable essence that generates the category's defining characteristics. Although essentialism may be an important determinant of consumers' cognitions about processed foods, there has been limited investigation of essentialism's role in food-related perceptions. Across two studies (n=598 total), we used a novel measure of food essentialism to examine whether individual differences in beliefs about foods as having essences (food essentialism) are related to perceptions of foods retaining more of their natural characteristics (sensory and nutritive properties) despite their level of processing. Across diverse food categories (meats, vegetables, fruits, legumes, dairy), higher levels of perceived food processing were associated with lower perceived retention of naturalness, nutritiousness, natural taste, functional post-ingestive benefits, and acceptability (liking). However, participants endorsing greater (vs. lower) food essentialism beliefs exhibited weaker relationships between perceived processing and these characteristics. We also observed variations across food categories in relationships between perceived level of processing and food properties, suggesting that some foods (i.e., milk-based products) are perceived to possess essences that are more robust despite undergoing higher levels of processing. These findings demonstrate that food-specific essentialism beliefs may be a fundamental determinant of consumers' expectations of how human intervention, such as processing, affects natural properties of foods. These beliefs may be a promising target for future research to shift consumer acceptance of processed foods.

Study protocol: How does cognitive flexibility relate to other executive functions and learning in healthy young adults?

BACKGROUND

Cognitive flexibility (CF) enables individuals to readily shift from one concept or mode of practice/thoughts to another in response to changes in the environment and feedback, making CF vital to optimise success in obtaining goals. However, how CF relates to other executive functions (e.g., working memory, response inhibition), mental abilities (e.g., creativity, literacy, numeracy, intelligence, structure learning), and social factors (e.g., multilingualism, tolerance of uncertainty, perceived social support, social decision-making) is less well understood. The current study aims to (1) establish the construct validity of CF in relation to other executive function skills and intelligence, and (2) elucidate specific relationships between CF, structure learning, creativity, career decision making and planning, and other life skills.

METHODS

This study will recruit up to 400 healthy Singaporean young adults (age 18-30) to complete a wide range of cognitive tasks and social questionnaires/tasks. The richness of the task/questionnaire battery and within-participant administration enables us to use computational modelling and structural equation modelling to examine connections between the latent constructs of interest.

SIGNIFICANCE AND IMPACT

The current study is the first systematic investigation into the construct validity of CF and its interrelationship with other important cognitive skills such as learning and creativity, within an Asian context. The study will further explore the concept of CF as a non-unitary construct, a novel theoretical proposition in the field. The inclusion of a structure learning paradigm is intended to inform future development of a novel intervention paradigm to enhance CF. Finally, the results of the study will be useful for informing classroom pedagogy and the design of lifelong learning policies and curricula, as part of the wider remit of the Cambridge-NTU Centre for Lifelong Learning and Individualised Cognition (CLIC).

[Study on the diagnostic value of transient elastography, APRI and FIB-4 for liver fibrosis in children with non-alcoholic fatty liver disease]

Objective: To evaluate the diagnostic value of transient elastography, aspartate aminotransferase-to-platelet ratio index (APRI), and fibrosis index based on 4 factors (FIB-4) for liver fibrosis in children with non-alcoholic fatty liver disease (NAFLD). Methods: A retrospective study was conducted on 100 cases of nonalcoholic fatty liver disease in Hunan Children's Hospital between August 2015 to October 2020 to collect liver tissue pathological and clinical data. The receiver operating characteristic curve (ROC curve) was used to analyze the diagnostic value of liver stiffness measurement (LSM), APRI and FIB-4 in the diagnosis of different stages of liver fibrosis caused by NAFLD in children. Results: The area under the ROC curve (AUC) value of LSM, APRI and FIB-4 for diagnosing liver fibrosis (S≥1) were 0.701 [95% confidence interval (CI): 0.579 ~ 0.822, P = 0.011], 0.606 (95%CI: 0.436 ~ 0.775, P = 0.182), and 0.568 (95%CI: 0.397 ~ 0.740, P = 0.387), respectively. The best cut-off values were 6.65 kPa, 21.20, and 0.18, respectively. The AUCs value of LSM, APRI, and FIB-4 for diagnosing significant liver fibrosis (S≥ 2) were 0.660 (95% CI: 0.552 ~ 0.768, P = 0.006), 0.578 (95% CI: 0.464 ~ 0.691, P = 0.182) and 0.541 (95% CI: 0.427 ~ 0.655, P = 0.482), respectively. The best cut-off values were 7.35kpa, 24.78 and 0.22, respectively. The AUCs value of LSM, APRI and FIB-4 for the diagnosis of advanced liver fibrosis (S≥ 3) were 0.639 (95% CI: 0.446 ~ 0.832, P = 0.134), 0.613 (95% CI: 0.447 ~ 0.779, P = 0.223) and 0.587 (95% CI: 0.411 ~ 0.764, P = 0.346), respectively. The best cut-off values were 8.55kpa, 26.66 and 0.27, respectively. Conclusion: The transient elastography technique has a better diagnostic value than APRI and FIB-4 for liver fibrosis in children with NAFLD.

[Therapeutic effects of target artery infusion of verapamil and chemotherapy drugs on advanced non-small cell lung cancer]

Objective: To investigate the effects of targeted artery perfusion of verapamil and chemotherapy drugs on advanced non-small cell lung cancer (NSCLC). Methods: Sixty patients with advanced NSCLC who were admitted to the Central Hospital of Zhumadian from April 2016 to April 2018 were selected as the research subjects. They were divided into the observation group (26 cases) and the control group (34 cases) according to the treatment method. Patients in the observation group were treated with targeted artery perfusion of verapamil and chemotherapy drugs while the control group were treated with target artery perfusion of chemotherapy drugs alone.Both groups were treated continuously for more than 2 months. The short-term curative effect, adverse reactions, changes in immune function, levels of serum tumor markers and Karnofsky Performance Scale (KPS) scores before and after treatment as well as the prognosis were compared between the two groups. Results: The response rate and control rate in the observation group were 80.8% and 96.2%, higher than 55.9% and 76.5% in the control group (P<0.05). After treatment, CD4(+) levels and CD4(+) /CD8(+) in the observation group were (25.43±2.76)% and (0.88±0.11), lower than (27.56±2.79)% and (0.95±0.13) in the control group (P<0.05). After treatment, serum levels of CEA and CA50 in the observation group were (11.57±2.32)ng/ml and (16.62±3.28)U/ml, also lower than (15.87±2.66)ng/ml and (20.31±3.42)U/ml in the control group (P<0.05). There was no significant difference in adverse reactions between the two groups (P>0.05). After treatment, KPS score of the observation group was (81.44±2.76) points, higher than (79.62±2.38) points of the control group (P<0.05). The median survival time and progression-free median survival time of the observation group were 16.0 months and 7.5 months, respectively, significantly better than 10.0 months and 5.0 months of the control group (P<0.05). Conclusions: The treatment with target arterial perfusion of verapamil and chemotherapy drugs for advanced NSCLC can effectively improve the short-term curative effect, reduce serum levels of tumor markers, improve life quality and prolong the survival time. However, it has a certain inhibitory effect on the patient's immune function.

[The Wuhan Twin Birth Cohort Study]

The prevalence of child and adolescent growth and mental-behavior related diseases are increasing, and the pathogenesis are complex. Twins are excellent natural resources for complex chronic diseases research as they share the maternal intrauterine environment, born at the same time and share the same family environment in early years, which could benefit the adjust ment of confounding factors, such as age, genetic factors and early family environmental factors. Birth cohort with twin families involved could be more effective in exploring the genetic and environmental factors for complex chronic diseases at the very beginning of life. This paper summarizes the objective, content, progress, strengths and potential problems of Wuhan Twin Birth Cohort, with emphasis on the overall design and progress of the study.

The Influence of Surface Bioactivated Modification on Titanium Percutaneous Implants Anchored in Bone

In order to achieve biological sealing and resist mechanical damage of load-bearing percutaneous devices, Ti with excellent mechanical properties was anodic-oxidized to be endowed with bioactivity, with plasma-sprayed hydroxyapatite coated Ti as control. Similar to previous works, hydroxyapatite coating could bond tightly with living tissues, resulting in implant stability for whole implantation periods. Meanwhile, when anodic-oxidized bioactivated Ti was implanted percutaneously in vivo, it could induce a layer of calcium phosphate at the interface of tissues/implant. This layer of Ca-P not only induced the fibrous tissue or collagen ingrowth in its structure, but also improved the osteointegration between the bone and the implant. There was no significant biological response difference for the anodic-oxidized Ti and HA coated Ti at different implantation period with histological statistical analysis (p>0.05). Accordingly, suitable bioactivated modified surface of Ti by anodic-oxidized method could not only obtain the same results as the HA coating, but also might avoid some drawbacks of plasma-sprayed HA coatings to achieve biological sealing for a long period in vivo.

[Efficacy and tolerance of Memantine monotherapy and combination therapy with Reinhartdt And Sea Cucumber Capsule on agitation in moderate to severe Alzheimer disease]

Objective: To explore the efficacy and tolerance of Memantine combined Reinhartdt And Sea Cucumber Capsule (R.S.C) on treating agitation in patients with moderate-severe Alzheimer disease (AD). Methods: One hundred and fifty-eight moderate-sever AD patients from Sep.2013 to Sep.2014 in Zhejiang Provincial People's Hospital were randomly divided into two groups: group of Memantine combined R. S.C and group of single Memantine. Then Mini-Mental Sate Examination (MMSE) and Neuropsychiatric Inventory (NPI) were used to evaluate cognition symptom, behavioral and psychological symptoms of dementia (BPSD) and agitation symptom at the baseline and the end of 24 weeks.The Treatment Emergent Symptom Scale (TESS) was used to assess adverse reaction and tolerance.At last, the data was analyzed by chi-square test, t-test and covariance test. Result: At the terminal of experience, the total NPI scores and agitation factor decreased markedly in both of the two groups (P<0.05). Among the patients who had agitation symptom at the baseline, the total NPI scores and agitation factor (18±5, 3.7±2.6) in group of Memantine combined R. S.C were notably lower than those in the group of single Memantine (21±6, 5.3±2.5) (P<0.05). The incidence of adverse reaction between the two groups had no significant difference (combined treatment group was 27.7%, single treatment group was 23.2%). One patient dropped out because of skin allergy, and most adverse reactions were tolerant. Conclusions: Both two groups are effective in agitation and BPSD, and Memantine combined R. S.C is better than single treatment.R.S.C dose not aggravate adverse reaction and can be well tolerated.

Enhanced effect of β-tricalcium phosphate phase on neovascularization of porous calcium phosphate ceramics: in vitro and in vivo evidence

Neovascularization plays a key role in bone repair and regeneration. In the present study, four types of porous calcium phosphate (CaP) ceramics, namely hydroxyapatite (HA), biphasic calcium phosphates (BCP-1 and BCP-2) and β-tricalcium phosphate (β-TCP), with HA to β-TCP ratios of 100/0, 70/30, 30/70 and 2/98, respectively, were investigated in terms of their angiogenic induction. The in vitro cell culture revealed that the ceramics could promote proliferation and angiogenesis of human umbilical vein endothelial cells (HUVECs). This result could be achieved by stimulating CCD-18Co human fibroblasts to secrete angiogenic factors (vascular endothelial growth factor, basic fibroblast growth factor and transforming growth factor-β) as a paracrine effect, as well as by up-regulating HUVECs to express these angiogenic factors and their receptors (KDR, FGFR1 and ACVRL1) and the downstream eNOS as an autocrine effect. These effects were more significant in β-TCP and BCP-2, which had a higher content of β-TCP phase. In the in vivo implantation into the thigh muscles of mice, the process of neovascularization of the ceramics was initiated at 2 weeks and the mature vascular networks were formed at 4 weeks as visualized by hematoxylin and eosin staining and scanning electron microscopy. Microvessel density count confirmed that β-TCP and BCP-2 induced more microvessels to form than HA or BCP-1. This phenomenon was further confirmed by the significantly up-regulated expressions of angiogenesis-related genes in the ingrowth of cells into the inner pores of the two ceramics. All the results confirmed the angiogenic induction of porous CaP ceramics, and a higher content of β-TCP phase had an enhanced effect on the neovascularization of the ceramics.

The effect of formoterol on airway goblet cell hyperplasia and protein Muc5ac expression in asthmatic mice

OBJECTIVES

Aim for this study was to investigate the effect of long-acting beta2-adrenoceptor agonist formoterol on airway goblet cell hyperplasia and protein Muc5ac expression in asthmatic mice.

MATERIALS AND METHODS

Forty female BABL/c mice were randomly divided into four groups with 10 mice in each. Mice in group A were treated with saline as control, and mice in group B, group C and group D were sensitized by intraperitoneal injection of 10 microg alum precipitated chicken egg ovalbumin (OVA) to establish asthmatic model, but group C were pretreated with formoterol and group D were pretreated with dexamethasone. All mice were killed 24 hours after the final OVA challenging. The left lung tissue sections were stained with periodic acid Schiff (PAS) for identification of goblet cell hyperplasia. Immunohistochemistry was used to identify the protein of Muc5ac. The right lung was isolated for detecting Muc5ac mRNA by the method of real-time fluorescence quantitative reverse transcription Polymerase Chain Reaction (real-time qRT-PCR).

RESULTS

The number of the goblet cells, the percentage of goblet cell to total cell, the transcription and the expression of Muc5ac were significantly higher in group B than those in group A [(163.63 +/- 16.68) vs. (0.46 +/- 0.16), (77.36 +/- 5.05) % vs. (0.03 +/- 0.01) % (10.31 +/- 0.73) vs. (1.00 +/- 0.13), (0.64 +/- 0.03) vs. (0.19 +/- 0.03) respectively, all P < 0.05]. The number of the goblet cells, the percentage of goblet cell to total cell, the transcription and the expression of Muc5ac were significantly lower in group C than those in group B [(52.04 +/- 4.60) vs (163.63 +/- 16.68), (30.05 +/-3.72) % vs. (77.36 +/- 5.05) %, (1.64 +/- 0.14) vs. (10.31 +/- 0.73), (0.26 +/- 0.01) vs (0.64 +/- 0.03) respectively, all P < 0.05] The number of the goblet cells, the percentage of goblet cell to total cell, the transcription and the expression of Muc5ac were significantly lower in group D than those in group B [(63.41 +/- 6.39) vs. (163.63 +/- 16.68), (38.52 +/- 3.83)% vs. (77.36 +/- 5.05) %, (1.72 +/- 0.10) vs. (10.31 +/- 0.73), (0.31 +/- 0.01) vs. (0.64 +/- 0.03) respectively, all P < 0.05]. For mentioned above, no significant differences were found between group C and group D [(52.04 +/- 4.60) vs. (63.41 +/- 6.39), (30.05 +/- 3.72) % vs. (38.52 +/- 3.83) %, (1.64 +/- 0.14) vs. (1.72 +/- 0.10), (0.26 +/- 0.01) vs. (0.31 +/- 0.01) respectively, all P < 0.05].

CONCLUSIONS

This study demonstrates that the long-acting beta2-receptor agonist formoterol may inhibit airway goblet cell hyperplasia and protein Muc5ac expression in asthmatic mice.

Regulation of bone-related genes expression by bone-like apatite in MC3T3-E1 cells

Bone-like apatite on HA/TCP ceramics sintered at 1,100 degrees C (HT1) and 1,200 degrees C (HT2) could be obtained via immersing substrates into simulated body fluid (SBF) for 3 days. When MC3T3-E1 preosteoblastic cells cultured on the surface of the bone-like apatite for 3 days, SEM observations revealed cell membrane features with secreted crystals very similar to in vivo bone formation during intramembranous ossification with a direct bone apposition on the ceramics. According to semi-quantitative RT-PCR method, mRNA expressions of osteocalcin (marker of late-stage differentiation) and type 1 collagen were increased in cultures with HT1S and HT2S when compared to HT1 and HT2 after cultured for 6 days. The results indicated that bone-like apatite had the ability to support the growth of osteoblast-like cells in vitro and to promote osteoblast differentiation by stimulating the expression of major phenotypic markers. Taken together, our findings will be helpful in understanding the mechanism of osteoinductivity of calcium phosphate ceramics and in constructing more appropriate biomimetic substrate.

Controllable release of salmon-calcitonin in injectable calcium phosphate cement modified by chitosan oligosaccharide and collagen polypeptide

The aim of this research is to study the effect of the controlled releasing character of the salmon calcitonin (S-CT) loaded injectable calcium phosphate cement (CPC) modified by adding organic phase, chitosan oligosaccharide (CO) and collagen polypeptide (CP). The uniform design was used to determine the basic formulation with suitable injectable time for clinical application, and then the changes of the physical characters, the controlled releasing character of the modified CPC along with the ratio of the organic phase were also evaluated in vitro. The surface morphous of the modified CPC been implanted in the abdominal cavity or soaked into the serum of rat was also observed by scanning electron microscope (SEM). The result shows that a suitable formulation of modified CPC could be got, and the injectable time is 12 min, the compressive strength is 12 MPa, and the final setting time is 40 min. Comparing with the CPC without organic phase, the releasing rate of S-CT would increase along with the increase of the organic phase after 7th day. Therefore, a novel S-CT loaded bioactive injectable CPC for treating osteoporosis induced bone defect was obtained, and the release of the containing S-CT was controlled easily through adjusting the ratio of CO and CP.

Neuroradiology imaging database: using picture archive and communication systems for brain tumour research

INTRODUCTION

Disease registries and databases form an important component of research in clinical medicine, and can be useful to support retrospective studies and prospective clinical trials. However, analysis of radiological imaging databases has not been explored: imaging and clinical data often exist as separate silos of information, even in modern digital-enabled hospitals in Singapore. We describe a computerised method for creating a radiological research database using data from the picture archive and communication system (PACS) and hospital information system (HIS).

METHODS

Using a relational database and Java programming language, we created the neuroradiology imaging database (NRID). A web-interface for keyword searches were tested with the clinical data from PACS of a tertiary referral hospital for neurological diseases. Keyword and wildcard searches were conducted for various brain neoplasms and compared to HIS discharge diagnosis.

RESULTS

The NRID was deployed successfully and keyword search could be completed in real time. Lists of patients with meningioma, oligodendroglial tumour, neurocytomas, cerebral abscess, and neurocysticercosis could be exported and compared with the HIS discharge diagnosis. Patients with neurological diseases could be obtained by manually combining lists.

CONCLUSION

An imaging database can be created using clinical PACS data, which can enable keyword search functions to support brain tumour research. Radiological databases can help support clinical research, but further work needs to be done in order to take full advantage of the potential of digital health information.

Global gene profiling analysis of mouse uterus during the oestrous cycle

Many genes related to the cyclic changes of the uterus during the oestrous cycle have been identified using a one-by-one approach. In the present study, cDNA microarray technology was applied to investigate the global profile of gene expression of mouse uterus at the oestrous and dioestrous stages. At a certain stage of the oestrous cycle, the uteri of mature CD-1 mice (n=10) were removed, pooled and snap-frozen in liquid nitrogen. Total RNA was extracted to synthesize cDNA probes for microarray assay. By screening 8192 mouse genes and expressed sequence tags (ESTs), 51 upregulated and 51 downregulated genes were identified in oestrous uterus, of which 62 are well characterized and 40 are ESTs. The known genes were assigned to various gene categories according to their main function. The microarray was performed three times with three independent sets of uterine tissue pools. The results of northern blot analysis for small proline-rich protein 2 (Sprr2), 17beta-hydroxysteroid dehydrogenase type 2 (17betaHSD-2), high mobility group 2 (Hmg2), mitotic checkpoint component 2 (Mad2) and an EST AW555366 mRNA were consistent with that of microarray analysis. In situ hybridization was performed to localize the transcript of the EST AW555366. Most of the upregulated genes encode secreted immune-related proteins, proteinases and their inhibitors, indicating their potential involvement in sperm viability as well as capacitation. The downregulated genes mainly encode cell cycle-related factors, implying the active proliferation of uterus at dioestrus.

Simultaneous improvement for four quality traits of Zhenshan 97, an elite parent of hybrid rice, by molecular marker-assisted selection

"Zhenshan 97" is the female parent of a number of widely used hybrids for rice production in China. However, this line is of poor quality because of a high amylose content (AC), a hard gel consistency (GC) and a low gelatinization temperature (GT), together with a chalky endosperm. It had been determined that the three traits for cooking and eating quality, AC, GC and GT, are controlled by the Waxy locus and/or the tightly linked genomic region. In this study we improved the eating and cooking quality of Zhenshan 97 by introgressing the Waxy gene region from Minghui 63 (wx-MH), a restorer line, that has medium AC, soft GC and high GT. The wx-MH fragment was transferred to Zhenshan 97B by three backcrosses and one selfing, then from Zhenshan 97B to Zhenshan 97A by a cross and a backcross. Molecular marker-assisted selection was applied in the series to select for individuals carrying wx-MH, to identify recombination between the Waxy and flanking markers, and also to recover the genetic background of the recurrent parent. According to the marker genotypes, the improved versions of Zhenshan 97B and Zhenshan 97A, or Zhenshan 97B(wx-MH) and Zhenshan 97A(wx-MH), were the same as the originals except for the Waxy region of less than 6.1 cM in length. The selected lines and their hybrids with Minghui 63, or Shanyou 63(wx-MH), showed a reduced AC and an increased GC and GT, coupled with a reduced grain opacity. Field examinations of agronomic performance revealed that Zhenshan 97B(wx-MH) and Shanyou 63(wx-MH) were essentially the same as the originals except for a significant decrease in grain weight. The simultaneous improvement of AC, GA, GT and opacity, indicated that the Waxy region had major effects on the four quality traits. The improved versions of Zhenshan 97 A and B should be immediately useful in hybrid rice production.

Modulation of the synchronization between cells in visual cortex by contextual targets

It has been suggested that synchronization of action potentials encodes diverse features of a single image. However, properties of the synchronization, which occurs on a time scale of approximately 1-5 ms, are still poorly understood. We have tested the modulation of synchronization by manipulating the contextual targets introduced in the surround of the receptive field. Experiments were carried out on anaesthetized cats prepared for multiunit and single-cell recordings in area 17. Initially, a patch of sine-wave drifting grating was positioned over the overlapping receptive fields of several neurons. If this coherent motion produced a significant synchronization in cross-correlograms, contextual targets were added. The first contextual stimuli were two sine-wave patches placed above and below the central compound receptive field. Only the contrast of contextual targets changed. Results show that the larger the differential contrast the higher the synchronization. The second contextual stimulus was a lateral shift of a sine-wave patch. Data show that the wider the distance between the central and peripheral patches the better the synchronization. Furthermore, results suggest that the synchrony pattern computed by cross correlating multiunit recordings from two sites differs when the cross correlation is carried out between individual units belonging to each multiunit recording. Together with our previous results it appears that synchronization is stimulus dependent and its strength increases with larger disparities included in the whole stimulating image.

[Studies of the correlation between fragile sites and giant panda's breeding problem]

An unique culture system has been established which can effectively indicate fragile sites induced by BrdU on giant panda chromosomes. After we cultured the lymphocytes of giant panda for 96 hours and treated it with low concentration of BrdU (10 micrograms/ml) for only a short time (4 hours), the areas of high-frequency-expressed fragile sites were successfully located on the centromeres of No. 2 and No. 12 chromosomes. After statistic analysis, we found that the frequency of fragile sites on No. 2 and No. 12 chromosomes are notably different among pandas. What is more important, the former is relative to giant pandas' breeding conditions and correlation coefficiency (r equals to -0.772). The result indicates that high frequency of fragile sites on No. 2 chromosome is unfavorable to giant panda's breeding and survival of filial generation.

[Analysis of QTL x environment interaction for rice panicle characteristics]

The development of molecular genetic linkage map has accelerated the identification and mapping of genomics regions controlling quantitative trait loci. A recombinant inbred line population derived from Zhenshan 97/Minghui 63 was grown in two years. Mixed linear model approach was used to jointly identify QTLs and QTL x environment interactions for five panicle characteristics. Ten, three, six, eight and seven QTLs were detected for spiketets per panicle, grains per panicle, seed setting, panicle length and panicle setting density, respectively. They collectively explained 29.13%, 19.2%, 29.46%, 26.39% and 35.76% of phenotypic variations for these traits, respectively. For the five traits, QTLs with increasing effects and decreasing effects could be simultaneously identified in high value parent and low value parent. QTLs for correlative traits clustering located in the similar regions. One QTL for panicle length, two QTLs for spikelets per panicle and three QTLs for seed setting performed significant interactions with environment. The contributions from interactions were slightly larger than that from the QTLs involved in the interactions. No QTL x environment interaction was detected for traits with high heritabilities such as grains per panicle and panicle setting density.

Comparative computations of spike synchronization in visual cortex of cats

In recent years it has been proposed that synchronous activity between neurons is a putative mechanism to bind together various trigger features of an image. Thus the measure of synchronization becomes an important issue since it may be an electrophysiological sign of visual perception. This paper describes and compares six techniques of computing synchronization strength, that is, the central peak of a cross-correlogram. Data were obtained in anesthetized cats prepared for electrophysiological recordings in a conventional fashion. Results indicate that: (1) eye fits are misleading. Visual inspection of cross-correlograms, may be interesting if one needs to estimate approximately synchronization strength and the presence of oscillations in the cross-correlograms, however it may be misleading if one wants to compare different cross-correlograms; (2) regression analysis to compare one method against the others yields a relatively poor correlation suggesting that methods are not directly comparable; (3) the sensitivity of each computational method is unequal. The results may indicate that some functional connections are either under- or over-evaluated depending upon the strategy employed to measure synchronization.

Stimuli outside the classical receptive field modulate the synchronization of action potentials between cells in visual cortex of cats

It is proposed that various attributes of an image are bound neuronally when responsive units fire in synchrony. Our investigations describe the influences of the contextual stimuli upon the occurrence of synchronization, in anaesthetized cats. Once a significant synchronization was recorded in the cross-correlogram (XCRG) between evoked action potentials of two groups of neurons in response to a drifting sine-wave grating, additional gratings were positioned outside the compound receptive field. The synchronization strength was then measured in relation to the difference between the orientations of the central and peripheral gratings. In the majority of cases results indicate that the synchronization is facilitated with larger orientation disparities. Thus, our data support the notion that contrasting features of images facilitate synchrony of activity between neurons.

The three important traits for cooking and eating quality of rice grains are controlled by a single locus in an elite rice hybrid, Shanyou 63

The cooking and eating quality of the rice grain is one of the most serious problems in many rice-producing areas of the world. In this study, we conducted a molecular marker-based genetic analysis of three traits, amylose content (AC), gel consistency (GC) and gelatinization temperature (GT), that are the most important constituents of the cooking and eating quality of rice grains. The materials used in the analysis included F(2) seeds, an F(2:3) population, and an F(9) recombinant inbred-line population from a cross between the parents of 'Shanyou 63', the most widely grown hybrid in rice production in China. Segregation analyses of these three generations showed that each of the three traits was controlled by a single Mendelian locus. Molecular marker-based QTL (quantitative trait locus) analyses, both by one-way analysis of variance using single marker genotypes and by whole-genome scanning with MAPMAKER/QTL, revealed a single locus that controls the expression of all three traits. This locus coincided with the Wx region on the short arm of chromosome 6, indicating that all three traits were either controlled by the Wx locus or by a genomic region tightly linked to this locus. This finding has provided clues to resolving the molecular bases of GC and GT in future studies. The results also have direct implications for the quality improvement of rice varieties.

[A study on the etiology and epidemiology of familial aggregation in arteriosclerotic cerebral infarction]

A case-control study including 214 pedigrees (109 cases and 105 controls) was carried out to explore the etiology of family aggregation of arteriosclerotic cerebral infarction in Yi-Xing city, March 1997. The results showed that the family member in both cases and control groups were comparable. The total prevalence rate of the first-degree relatives in cases was 5.12%, significantly higher than (1.63%) that noticed in controls, with chi 2 = 16.40 (P < 0.01). The same results was also found in their parents and siblings. Results from binominal distribution analysis showed that the number of cases in the families of arteriosclerotic cerebral infarction was significantly higher than the theortical range which indicated that there was significant familial aggregation in the occurance of arteriosclerotic cerebral infarction. Logistic regression model also showed that genetic factor was one of the most important risk factors in Xi-xing, Jiangsu. Dose-response was observed in this model. The heritability and the segregation ratio of arteriosclerotic cerebral infarction were the same as seen in other chronic diseases, such as coronary heart disease and esophageal cancer.

Importance of epistasis as the genetic basis of heterosis in an elite rice hybrid

The genetic basis of heterosis was investigated in an elite rice hybrid by using a molecular linkage map with 150 segregating loci covering the entire rice genome. Data for yield and three traits that were components of yield were collected over 2 years from replicated field trials of 250 F(2:3) families. Genotypic variations explained from about 50% to more than 80% of the total variation. Interactions between genotypes and years were small compared with the main effects. A total of 32 quantitative trait loci (QTLs) were detected for the four traits; 12 were observed in both years and the remaining 20 were detected in only one year. Overdominance was observed for most of the QTLs for yield and also for a few QTLs for the component traits. Correlations between marker heterozygosity and trait expression were low, indicating that the overall heterozygosity made little contribution to heterosis. Digenic interactions, including additive by additive, additive by dominance, and dominance by dominance, were frequent and widespread in this population. The interactions involved large numbers of marker loci, most of which individually were not detectable on single-locus basis; many interactions among loci were detected in both years. The results provide strong evidence that epistasis plays a major role as the genetic basis of heterosis.