Robustness of open source community multi-project knowledge collaboration network based on structural hole theory.

Nodes in the structural hole position play a key role in the multi-project network of the open source community (OSC). This paper studies the robustness of this network based on structural hole theory. First, a semantic-based multi-project KCN is constructed, and four node types are identified: knowledge contribution nodes, knowledge dissemination nodes, structural hole nodes (SHNs) and opinion leader nodes. Second, a robustness analysis model of the edge failures of these four key nodes is constructed. Third, a simulation test is conducted on the proposed model using empirical data from the Local Motors multi-project OSC. The results show that the KCN has the lowest robustness when facing the edge failure of opinion leader nodes, followed by knowledge dissemination nodes, knowledge contribution nodes, SHNs and random nodes. The edge failure of opinion leader nodes causes the lowest network robustness because of the propagation effect of these nodes. Additionally, SHN failure has only a small initial impact on connectivity, whereas knowledge collaboration efficiency decreases rapidly (i.e., the edge failure of SHNs causes the network to enter a state of high connectivity and low efficiency). The proposed model can be used to provide comprehensive and targeted management guidance for OSC development.

Advances in Pickering emulsions stabilized by protein particles: Toward particle fabrication, interaction and arrangement.

With the increasing global demand for clean-label and sustainable emulsifiers that are suitable for use in agrochemicals, personal care and food industry, protein-based particles are becoming promising emulsion stabilizer in food industry owing to their considerable surface activity, biodegradability and excellent nutritional value. Accumulating evidence implies that, relative to classical rigid inorganic particles, protein colloidal particles perform more as soft particles to stabilize emulsions. A brief historical introduction to Pickering emulsions provides a conceptual framework firstly. Then, the conformational properties and methods of fabrication and modification of protein-based particles are introduced in more detail. In addition, the particle shape, interfacial arrangement and interaction are also discussed. Finally, novel application of these materials and future perspectives concerning the interfacial conformation, rheology and industrial production of protein-based Pickering particles are considered. In summary, thermal and solvent-induced aggregation are found to be the principal fabrication methods of protein-based Pickering particles. Through the complexation or covalent interaction with polysaccharides, proteins and phenolics, protein particles exhibit improved solubility, emulsification effectiveness and bioactive functionalities. According to different shapes, protein-based Pickering particles can be categorized into elongated and linear particles, spherical particles, plate-shaped particles, and fractal aggregates, which have different interfacial adsorption energy. Overall, the embedding arrangement, interfacial rheology and large-scale production of protein particles are challenges as well as opportunities that coexist in further studies.

Occurrence of crop pests and diseases has largely increased in China since 1970.

Crop pests and diseases (CPDs) are emerging threats to global food security, but trends in the occurrence of pests and diseases remain largely unknown due to the lack of observations for major crop producers. Here, on the basis of a unique historical dataset with more than 5,500 statistical records, we found an increased occurrence of CPDs in every province of China, with the national average rate of CPD occurrence increasing by a factor of four (from 53% to 218%) during 1970-2016. Historical climate change is responsible for more than one-fifth of the observed increment of CPD occurrence (22% ± 17%), ranging from 2% to 79% in different provinces. Among the climatic factors considered, warmer nighttime temperatures contribute most to the increasing occurrence of CPDs (11% ± 9%). Projections of future CPDs show that at the end of this century, climate change will lead to an increase in CPD occurrence by 243% ± 110% under a low-emissions scenario (SSP126) and 460% ± 213% under a high-emissions scenario (SSP585), with the magnitude largely dependent on the impacts of warmer nighttime temperatures and decreasing frost days. This observation-based evidence highlights the urgent need to accurately account for the increasing risk of CPDs in mitigating the impacts of climate change on food production.

Comment on "Recent global decline of CO2 fertilization effects on vegetation photosynthesis".

Wang et al. (Research Articles, 11 December 2020, p. 1295) reported a large decline in the CO2 fertilization effect (CFE) on global photosynthesis, on the basis of changing regression coefficients of CO2 (ß) for satellite proxies/products of photosynthesis. We show that their methods cannot robustly estimate CFE, leading to incorrect attribution, and largely neglect CO2 effects on the photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase-oxygenase (RuBisCO).

An Overview on Collagen and Gelatin-Based Cryogels: Fabrication, Classification, Properties and Biomedical Applications.

Decades of research into cryogels have resulted in the development of many types of cryogels for various applications. Collagen and gelatin possess nontoxicity, intrinsic gel-forming ability and physicochemical properties, and excellent biocompatibility and biodegradability, making them very desirable candidates for the fabrication of cryogels. Collagen-based cryogels (CBCs) and gelatin-based cryogels (GBCs) have been successfully applied as three-dimensional substrates for cell culture and have shown promise for biomedical use. A key point in the development of CBCs and GBCs is the quantitative and precise characterization of their properties and their correlation with preparation process and parameters, enabling these cryogels to be tuned to match engineering requirements. Great efforts have been devoted to fabricating these types of cryogels and exploring their potential biomedical application. However, to the best of our knowledge, no comprehensive overviews focused on CBCs and GBCs have been reported currently. In this review, we attempt to provide insight into the recent advances on such kinds of cryogels, including their fabrication methods and structural properties, as well as potential biomedical applications.

Global irrigation contribution to wheat and maize yield.

Irrigation is the largest sector of human water use and an important option for increasing crop production and reducing drought impacts. However, the potential for irrigation to contribute to global crop yields remains uncertain. Here, we quantify this contribution for wheat and maize at global scale by developing a Bayesian framework integrating empirical estimates and gridded global crop models on new maps of the relative difference between attainable rainfed and irrigated yield (ΔY). At global scale, ΔY is 34 ± 9% for wheat and 22 ± 13% for maize, with large spatial differences driven more by patterns of precipitation than that of evaporative demand. Comparing irrigation demands with renewable water supply, we find 30-47% of contemporary rainfed agriculture of wheat and maize cannot achieve yield gap closure utilizing current river discharge, unless more water diversion projects are set in place, putting into question the potential of irrigation to mitigate climate change impacts.

Purification, characterization, and gene cloning of two laccase isoenzymes (Lac1 and Lac2) from Trametes hirsuta MX2 and their potential in dye decolorization.

In this study, two laccase isoenzymes (Lac1 and Lac2) from the culture supernatant of Trametes hirsuta MX2 were purified, and the genes (Lac1 and Lac2) coding the isoenzymes were cloned. Both Lac1 and Lac2 contained an open reading frame of 1563 bp with an identity of 79%. The two isoenzymes showed significant biochemical differences. The maximal activities of Lac1 and Lac2 were at pH 2.5 with 2-2'-azino-di-(3-ethylbenzthiazoline sulfonic acid) (ABTS), and the optimal temperatures for the activities of Lac1 and Lac2 were 60 and 50 °C, respectively. Lac1 exhibited excellent resistance to acidic conditions and retained 62.17% of its initial activity at pH 2.5 after a 72-h incubation. Lac2 was more thermostable than Lac1 with half-lives (t1/2) of 9.58 and 3.12 h at 50 and 60 °C, respectively; the t1/2 of Lac1 were only 4.19 and 0.88 h, respectively. Both Lac1 and Lac2 isoenzymes have a strong tolerance to Mg2+, Mn2+, Cu2+, and EDTA (50 mM). At a low concentration of 0.05 U mL-1, the enzymes could decolorize towards Remazol Brilliant Blue R, Acid Red 1, Crystal Violet, and Neutral Red in the presence of ABTS. These unusual properties demonstrated that the two laccases have strong potential for specific industrial applications.

Shelf life prediction and food safety risk assessment of an innovative whole soybean curd based on predictive models.

The aim of the present study is to predict the shelf life and evaluate the risk profile of an innovative whole soybean curd (WSC). Two main spoilage strains were isolated from spoiled WSC and identified as B. subtilis and B. cereus. The origin analysis confirmed that B. subtilis and B. cereus originated from soybean materials and survived in soybean curd. For microbial contamination analysis, thermotolerant coliforms, E. coli and S. aureus were not detected in soybean curd. The predicted shelf life of WSC and okara-filtered curd that was stored at 10 °C were 141.95 h (5.91 d) and 206.25 h (8.59 d), respectively. Moreover, the models applied in this study exhibited great fitting goodness and the predicted growth parameters were fail-safe. To conclude, introduction of okara into soybean curd reinforced the initial contamination level but didn't significantly increase the risk profile of WSC.

Spoilage Bacteria Identification and Food Safety Risk Assessment of Whole Soybean Curd.

As a highly hydrated gel-type food, soybean curd is perishable and the development of spoilage bacteria has been described. Whole soybean curd (WSC), an innovative soy product retains the most nutrients in raw ingredients and exhibits more nutritive value compared with conventional soybean curd (CSC). However, the risk assessment of WSC is not well evaluated up to now. In this study, the same species of spoilage microorganism were separated from WSC and CSC. Two main spoilage strains were separated and identified as B. subtilis and B. cereus. The risk ranking scores of WSC was higher than that of CSC but still within medium risk range. In summary, we reported the presence of B. subtilis and B. cereus in WSC for the first time. Further, application of the risk ranger tool confirmed that the risk profile of WSC was medium and acceptable.

Application of transglutaminase for quality improvement of whole soybean curd.

To improve the quality of whole soybean curd (WSC), effects of compound coagulants consisting of calcium chloride (CaCl2) and transglutaminase (TGase) were investigated. The results showed that TGase modified the water distribution and reduced the cooking loss of WSC, accompanying with increased water holding capacity. The bloom value of WSC was upgraded as the TGase concentration increased. Although certain sensory parameters showed different scores in groups, the overall acceptability of 1500 ppm group was the highest. TPA test suggested that hardness, springiness and chewiness were promoted by TGase significantly. Smooth appearance of WSC was observed, resulting from the transformation of microstructure. Protein subunits of 7Sα', 7Sα, 7Sß, 11SA3, 11S acidic, and 11S basic proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, band intensity of protein subunits declined at storage and cooking phase, indicating that crosslinking of proteins was still in progress. In conclusion, the addition of TGase improved the quality of CaCl2-induced WSC and could be used to facilitate the production of this new type of soybean product.

Mortality effects of heat waves vary by age and area: a multi-area study in China.

BACKGROUND: Many studies have reported an increased mortality risk from heat waves comparing with non-heat wave days. However, how much the mortality rate change with the heat intensity-vulnerability curve-is still unknown. Such unknown information makes the related managers impossible to assess scientifically life losses from heat waves, consequently fail in conducting suitable integrated risk management measures. METHODS: We used the heat wave intensity index (HWII) to characterize quantitatively the heat waves, then applied a distributed lag non-linear model to explore the area-specific definition of heat wave, and developed the vulnerability models on the relationships between HWII and mortality by age and by area. Finally, Monte Carlo method was run to assess and compare the event-based probabilistic heat wave risk during the periods of 1971-2015 and 2051-2095. RESULTS: We found a localized definition of heat wave for each corresponding area based on the minimum AIC (Akaike information criterion). Under the local heat wave events, the expected life loss during 1971-2015 does distinguish across areas, and decreases consistently in the order of WZ Chongqing, PK Nanjing and YX Guangzhou for each age group. More specifically, for the elders (≥65), the average annual loss (AAL) (and 95% confidence interval) would be 61.3 (30.6-91.9), 38 (3.8-72.2) and 18.7 (7.3-30) deaths per million people. With two stresses from warming and aging in future China, the predicted average AAL of the elders under four Representative Carbon Pathways (2.6, 4.5, 6.0, and 8.5) during 2051-2095 would be 2460, 1675, 465 deaths per million for PK Nanjing, YX Guangzhou and WZ Chongqing, respectively, approximately becoming 8~ 90 times of the AAL during 1971-2015. CONCLUSION: This study found that the non-linear HWII-mortality relationships vary by age and area. The heat wave mortality losses are closely associated with the social-economic level. With the increasing extreme climatic events and a rapid aging trend in China, our findings can provide guidance for policy-makers to take appropriate regional adaptive measures to reduce health risks in China.

Different response of human mortality to extreme temperatures (MoET) between rural and urban areas: A multi-scale study across China.

BACKGROUND: The environmental variation in mortality due to extreme temperatures has been well-documented by many studies. Mortality to extreme temperatures (MoET) was recognized to vary geographically, either by countries within a region or by areas within a country. However, so far, little attention has been paid to rural residents, with even lesser attention on the potential rural-urban differences. The aim of our study was to offer a quite comprehensive analysis on the differences in temperature-mortality relationship between rural and urban areas across China. METHOD: A distributed lag nonlinear model was built to describe the temperature-mortality relationship, based on the mortality data and meteorological variable of 75 communities in China from 2007 to 2012. Subsequently, a meta-analysis was applied to compare the differences in the temperature-mortality relationship between rural and urban areas at various levels. RESULTS: Distinct responses regarding MoET between rural and urban areas were observed at different spatial scales. At regional level, more U-shaped curves were observed for temperature-mortality relationships in urban areas, while more J-shaped curves were observed in rural areas. At national scale, we found that the cold effect was stronger in rural areas (RR: rural 1.69 vs. urban 1.51), while heat effect was stronger in urban areas (RR: rural 1.01 vs. urban 1.12). Moreover, the modifying influence of air pollution on temperature-mortality relationship was found to be very limited. CONCLUSION: The difference in response of MoET between rural and urban areas was noticeable, cold effect is more significant in China both in rural and urban areas. Additionally, urban areas in southern China and rural areas in northern China suffered more from extreme temperature events. Our findings suggest that differences in rural-urban responses to MoET should be taken seriously when intervention measures for reducing the risks to residents' health were adopted.

Research progress in tofu processing: From raw materials to processing conditions.

As a traditional soybean product with good quality and a healthy food with many functional components, tofu is increasingly consumed in people's daily life. Traditional tofu processing consists of numerous steps, including the soaking and grinding of soybean seeds, heating of the soybean slurry, filtering, and addition of coagulants, and others. The properties of soybean seeds, processing scale, soaking and heating conditions, type and concentration of coagulant, and other factors collectively impact the processing steps and the final tofu quality. The generation of whole soybean tofu with more nutritive value comparing with traditional tofu has been successfully reported by several studies. As one of the most important functional component, isoflavones and their presence in tofu are also influenced by the above-mentioned factors, which influence the nutritive value of tofu. Research investigating the influence of tofu processing conditions on the quality and isoflavone profiles of tofu are the subject of this review. Issues that should be further studied to investigate the influence of processing conditions on the quality and nutritive value of tofu are also introduced.

Evaluation of the non-aldehyde volatile compounds formed during deep-fat frying process.

To investigate the non-aldehyde volatile profile resulting from deep-fat frying, volatile compounds formed during the processes of heating soybean oil (SO), frying wheat dough (WD), and frying chicken breast meat (CBM) were comparatively studied. By using gas chromatography-mass spectrometry and internal standard method, alkanes, alkenes, alkynes, alcohols, ketones, nitrogen-containing volatiles (NCVs), and other volatiles were qualitatively and relatively quantitatively detected. NCVs were detected only in CBM-fried oil samples. Some volatiles (e.g. 2-pentylfuran and 2-pentylpyridine) were observed to increase in concentration, whereas others (e.g. 4-methyl-1,4-heptadiene and 7-methyl-3,4-octadiene) were observed to first increase and then decrease in concentration as the heating or frying time increased. Reduced quantity and concentrations of volatiles were observed in the food-fried oil samples which might be related to the intensified reactions induced by food components. The detection of some harmful volatiles in considerable concentrations indicated further attention might be paid to the safety of deep-fat frying.

Nonlinear relationship between extreme temperature and mortality in different temperature zones: A systematic study of 122 communities across the mainland of China.

BACKGROUND: Numerous previous studies have reported that human health risk is extremely sensitive to temperature. Very few studies, however, have characterized the relationship between temperature and mortality in different temperature zones due to the previous conclusions deduced from a regional or administrative division. A research covers different temperature zones was indispensable to have a comprehensive understanding of regional ambient temperature effect on public health. METHODS: Based on the mortality dataset and meteorological variables of 122 communities in China from 2007 to 2012, a distributed lag nonlinear model (DLNM) was utilized to estimate the temperature effect on non-accidental mortality at the community level. Then, a meta-regression analysis was applied to pool the estimates of community-specific effects in various latitude-effected temperature zones. RESULTS: At the community level, the mean value of relative extreme cold risk (1.63) of all 122 communities was higher than that of extreme high temperature (1.15). At regional level, we found temperature-mortality relationship (e.g., U- or J-shaped) varied in different temperature zones. Meanwhile, the minimum-mortality temperature of each zone was near the 75th percentile of local mean temperature except the north subtropics (50th percentiles). Lag effect was also obvious, especially for cold effect. An interesting M-shaped curve for the relationship between cold risk and temperature was detected, while an inverted "U" shaped with a right tail for the heat effect. Such different responses might be attributed to the difference in social-economic status of temperature zones. CONCLUSION: The temperature-mortality relationship showed a distinct spatial heterogeneity along temperature zones across the Chinese mainland. Different characteristics of mortality responding to cold and heat stress highlighted the fact that, apart from the circumstance of temperature, the social-economic condition was also linked with health risk. Our findings suggest decision-makers should take more adaptive and effective measures to reduce health risks in China.

Thyroid hormone resistance syndrome caused by heterozygous A317T mutation in thyroid hormone receptor ß gene: Report of one Chinese pedigree and review of the literature.

BACKGROUND: Thyroid hormone resistance syndrome (THRS) is a rare disorder with increased concentrations of free thyroxine (FT4) and triiodothyronine (FT3), but normal or slightly increased thyroid-stimulating hormone (TSH). The mutations in the thyroid hormone receptor ß (THRß) gene are thought to be the main pathogenesis. OBJECTIVES: The aims of this study were to present 1 pedigree of Chinese THRS, summarize their clinical characteristics, and analyze the gene mutation. METHODS: The clinical characteristics and thyroid function of the proband and his family members were collected. Gene mutations were analyzed by DNA sequencing. RESULTS: The proband and his mother exhibited symptoms of hyperthyroidism, such as palpitations, heat intolerance, and perspiration. The mother also had atrial fibrillation. The rest of the kindred did not display clinical manifestations of hyper- or hypothyroidism. DNA sequencing revealed a heterozygous G>A missense mutation at position 949 in Exon 9 of THRß both in the patient and his mother, which led to the transition from alanine to threonine at position 317 of THRß protein (A317T), whereas the rest of the kindred did not share this mutation. The proband and his mother were diagnosed with pituitary resistance to thyroid hormone. Oral administration of methimazole was stopped and ß-receptor blockers were administrated. CONCLUSIONS: We present 1 pedigree of THRS with heterozygous A317T mutation in THRß gene in the proband and his mother, which is the first reported mutation in Chinese and provides a comprehensive review of available literature.

Sodium Fluoride for Protection of Wood Against Field Populations of Subterranean Termites.

Sodium fluoride (NaF) is a wood preservative with fungicidal activity and antifeedant activity against termites. In this study, wood blocks of Pinus massoniana were treated with a 0.5% (wt/wt) aqueous solution of NaF, and placed in soil contact under field conditions to evaluate leachability of NaF and resistance to Reticulitermes flaviceps (Oshima). Fluoride leachate levels in soil from wood-soil locations were also determined. After 12-mo outdoor exposure, 91.54% of fluoride was leached from NaF-treated wood and fluoride retention of the wood was 154.28 µg/g wood. In NaF-treated wood-soil locations, soil fluoride residues were significantly higher than locations with the water-treated negative control. Termite activity (presence or occupation) on NaF-treated blocks was 6.25% which was significantly less than 40.00% activity on water-treated control blocks. The mass lost from the wood of NaF-treated blocks was 17.46% which was significantly less than the 45.21% loss from the water-treated blocks. The results show that fluoride is readily leachable from treated wood into surrounding soil. NaF treatment can reduce termite damage to wood under field conditions, and this compound should receive further consideration as a wood preservative to protect timber from termite damage.

Computational study of human head response to primary blast waves of five levels from three directions.

Human exposure to blast waves without any fragment impacts can still result in primary blast-induced traumatic brain injury (bTBI). To investigate the mechanical response of human brain to primary blast waves and to identify the injury mechanisms of bTBI, a three-dimensional finite element head model consisting of the scalp, skull, cerebrospinal fluid, nasal cavity, and brain was developed from the imaging data set of a human female. The finite element head model was partially validated and was subjected to the blast waves of five blast intensities from the anterior, right lateral, and posterior directions at a stand-off distance of one meter from the detonation center. Simulation results show that the blast wave directly transmits into the head and causes a pressure wave propagating through the brain tissue. Intracranial pressure (ICP) is predicted to have the highest magnitude from a posterior blast wave in comparison with a blast wave from any of the other two directions with same blast intensity. The brain model predicts higher positive pressure at the site proximal to blast wave than that at the distal site. The intracranial pressure wave invariably travels into the posterior fossa and vertebral column, causing high pressures in these regions. The severities of cerebral contusions at different cerebral locations are estimated using an ICP based injury criterion. Von Mises stress prevails in the cortex with a much higher magnitude than in the internal parenchyma. According to an axonal injury criterion based on von Mises stress, axonal injury is not predicted to be a cause of primary brain injury from blasts.