The wall of an expanding plant cell consists primarily of cellulose microfibrils embedded in a matrix of hemicellulosic and pectic polysaccharides along with small amounts of structural and enzymatic proteins. Matrix ...The wall of an expanding plant cell consists primarily of cellulose microfibrils embedded in a matrix of hemicellulosic and pectic polysaccharides along with small amounts of structural and enzymatic proteins. Matrix polysaccharides are synthesized in the Golgi and exported to the cell wall by exocytosis, where they intercalate among cellulose microfibrils, which are made at the plasma membrane and directly deposited into the cell wall. Involvement of Golgi glucan synthesis in auxin-induced cell expansion has long been recognized; however, only recently have the genes corresponding to glucan synthases been identified. Biochemical purification was unsuccessful because of the labile nature and very low abundance of these enzymes. Mutational genetics also proved fruitless. Expression of candidate genes identified through gene expression profiling or comparative genomics in heterologous systems followed by functional characterization has been relatively successful. Several genes from the cellulose synthase-like （Csl） family have been found to be involved in the synthesis of various hemicellulosic glycans. The usefulness of this approach, however, is limited to those enzymes that probably do not form complexes consisting of unrelated proteins. Nonconventional approaches will continue to incrementally unravel the mechanisms of Golgi polysaccharide biosynthesis.展开更多
Sedimentation based processes are widely used in industry to separate particles from a liquid phase. Since the advent of the ＂Nanoworld＂ the demand for effective separation technologies has rapidly risen, calling fo...Sedimentation based processes are widely used in industry to separate particles from a liquid phase. Since the advent of the ＂Nanoworld＂ the demand for effective separation technologies has rapidly risen, calling for the development of new separation concepts, one of which lies in hybrid separation using the superposition of a magnetic field for magnetic particles. Possible product portfolio of such separation consists of pigment production, nanomagnetics production for electronics and bio separation, A promising step in that direction is magnetic field enhanced cake filtration, which has by now progressed from batch to continuous ooeration. In sedimentation processes in a mass force field the settling behaviour of particles strongly depends on physico-chemical properties, concentration and size distribution of the particles. By adjusting the pH, the interparticle forces, in particular the electrostatic repulsion, can be manipulated. For remanent magnetic particles such as magnetite, pre-treatment in a magnetic field could lead to a change of interparticle interactions. By magnetizing the particles apart from van der Waals attraction and electrostatic repulsion, an additional potential is induced, the magnetic attraction, which could easily dominate the other potentials and result in agglomeration in the primary minimum. By sedimentation analysis, a wide spectrum of parameters like pH, magnetic field strength and concentration have been investigated. The results show a strong increase of sedimentation velocity by magnetic flocculation of the raw suspension. This leads to a rise in throughput due to the acceleration of sedimentation kinetics by imparting a non-chemical interaction to the physico-chemical properties in the feed stream of the separation apparatus.展开更多
During daylight, plants produce excess photo- synthates, including sucrose, which is temporarily stored in the vacuole. At night, plants remobilize sucrose to sustain metabolism and growth. Based on homology to other ...During daylight, plants produce excess photo- synthates, including sucrose, which is temporarily stored in the vacuole. At night, plants remobilize sucrose to sustain metabolism and growth. Based on homology to other sucrose transporter （SUT） proteins, we hypothesized the maize （Zea mays） SUCROSE TRANSPORTER2 （ZmSUT2） protein functions as a sucrose/H^＋ symporter on the vacuolar membrane to export transiently stored sucrose. To understand the biological role of ZmSut2, we examined its spatial and temporal gene expression, determined the protein subcellular localization, and characterized loss-of- function mutations. ZmSut2 mRNA was ubiquitously expressed and exhibited diurnal cycling in transcript abundance. Expressing a translational fusion of ZmSUT2 fused to a red fluorescent protein in maize mesophyll cell protoplasts revealed that the protein localized to the tonoplast. Under field conditions, zmsut2 mutant plants grew slower, possessed smaller tassels and ears, and produced fewer kernels when compared to wild-type siblings, zmsut2 mutants also accumulated two-fold more sucrose, glucose, and fructose as well as starch in source leaves compared to wild type. These findings suggest （i） ZmSUT2 functions to remobilize sucrose out of the vacuole for subsequent use in growing tissues; and （ii） its function provides an important contribution to maize development and agronomic yield.展开更多
This review provides a critical overview of the recent methods and processes developed for the production of cellulose nanoparticles with controlled morphology, structure and properties, and also sums up (1) the proce...This review provides a critical overview of the recent methods and processes developed for the production of cellulose nanoparticles with controlled morphology, structure and properties, and also sums up (1) the processes for the chemical modifications of these particles in order to prevent their re-aggregation during spray-drying procedures and to increase their reactivity, (2) the recent processes involved in the production of nanostructured biomaterials and composites. The structural and physical properties of those nanocelluloses, combined with their biodegradability, make them materials of choice in the very promising area of nanotechnology, likely subject to major commercial successes in the context of green chemistry. With a prospective and pioneering approach to the subject matter, various laboratories involved in this domain have developed bio-products now almost suitable to industrial applications;although some important steps remain to be overcome, those are worth been reviewed and supplemented. At this stage, several pilot units and demonstration plants have been built to improve, optimize and scale-up the processes developed at laboratory scale. Industrial reactors with suitable environment and modern control equipment are to be expected within that context. This review shall bring the suitable processing dimension that may be needed now, given the numerous reviews outlining the product potential attributes. An abundant literature database, close to 250 publications and patents, is provided, consolidating the various research and more practical angles.展开更多
AIM: To determine the efficacy of probiotic supplementation on intestinal transit time (ITT) and to identify factors that influence these outcomes. METHODS: A systematic review of randomized controlled trials (RCTs) o...AIM: To determine the efficacy of probiotic supplementation on intestinal transit time (ITT) and to identify factors that influence these outcomes. METHODS: A systematic review of randomized controlled trials (RCTs) of probiotic supplementation that measured ITT in adults was conducted by searching MEDLINE and EMBASE using relevant combinations. Main search limits included RCTs of probiotic supplementation in healthy or constipated adults that measured ITT. Study quality was assessed using the Jadad scale. A random effects meta-analysis was performed with standardized mean difference (SMD) of ITT between probiotic and control groups as the primary outcome. Meta-regression and subgroup analyses were conducted to examine the impact of moderator variables on ITT SMD. RESULTS: A total of 11 clinical trials with 13 treatment effects representing 464 subjects were included in this analysis. Probiotic supplementation was associated with decreased ITT in relation to controls, with an SMD of 0.40 (95%CI: 0.20-0.59, P < 0.001). Constipation (r 2 = 39%, P = 0.01), higher mean age (r 2 = 27%, P = 0.03), and higher percentage of female subjects (r 2 = 23%, P < 0.05) were predictive of decreased ITT with probiotics in meta-regression. Subgroup analyses demonstrated statistically greater reductions in ITT with probiotics in subjects with vs without constipation and in older vs younger subjects [both SMD: 0.59 (95%CI: 0.39-0.79) vs 0.17 (95%CI: -0.08-0.42), P = 0.01]. Medium to large treatment effects were identified with Bifidobacterium Lactis (B. lactis ) HN019 (SMD: 0.72, 95%CI: 0.27-1.18, P < 0.01) and B. lactis DN-173 010 (SMD: 0.54, 95%CI: 0.15-0.94, P < 0.01) while other single strains and combination products yielded small treatment effects. CONCLUSION: Overall, short-term probiotic supplementation decreases ITT with consistently greater treatment effects identified in constipated or older adults and with certain probiotic strains.展开更多
AIM To determine the effects of Lactobacillus acidophilus NCFM on irritable bowel syndrome(IBS) symptoms and quality of life(Qo L).METHODS In this randomized triple-blind trial, adult IBS volunteerswho were recruited ...AIM To determine the effects of Lactobacillus acidophilus NCFM on irritable bowel syndrome(IBS) symptoms and quality of life(Qo L).METHODS In this randomized triple-blind trial, adult IBS volunteerswho were recruited according to Rome Ⅲ criteria received 109 or 1010 colony-forming units of NCFM or placebo daily for 12 wk. IBS Symptom Severity Score(IBS-SSS), which constituted the primary outcome, and secondary outcomes, including individual IBS symptoms, IBS-related QoL questionnaire, anxiety and depression, defecation frequency, and stool consistency, were assessed at baseline at the end of the 8-wk runin period, after 4 and 12 wk of intervention, and after a 4-wk washout.RESULTS A total of 340 of 391 randomized volunteers completed the trial. IBS-SSS improved over 12 wk of treatment in all treatment groups, decreasing by a mean ± SD of 44.0 ± 80.2, 50.8 ± 82.4, and 48.3 ± 72.2 in the placebo, active low-dose, and active high-dose groups, respectively. Similarly, secondary outcomes did not differ between treatment groups. However, in a post hoc analysis of volunteers with moderate to severe abdominal pain at baseline(VAS > 35/100), the treatment significantly reduced the sensation of abdominal pain. Pain scores fell by 20.8 ± 22.8, 29.4 ± 17.9, and 31.2 ± 21.9 in the placebo, active low-dose, and active high-dose groups, respectively(P value for placebo vs combined active doses = 0.0460).CONCLUSION NCFM alleviates moderate to severe abdominal pain, consistent with earlier observations of this strain mitigating visceral pain through increased analgesic receptor expression.展开更多
In this study,an improved impedance tube test method is proposed to determine the sound absorption coefficients of materials at high frequencies up to 10 kHz.Specifically,a multi-modal decomposition method is used to ...In this study,an improved impedance tube test method is proposed to determine the sound absorption coefficients of materials at high frequencies up to 10 kHz.Specifically,a multi-modal decomposition method is used to measure the sound absorption coefficients above the cut-off frequency of plane waves in the impedance tube.During the measurement process,an array of microphones is placed in the circumferential and axial directions of the tube.Then,the first three acoustic circumferential modes are decomposed,and the corresponding axial incident and reflected waves at each mode are recorded by the array of microphones.The accuracy and feasibility of the proposed multi-modal decomposition method are validated by comparing the measurement results with those obtained using the conventional impedance tube method.展开更多
The whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most devastating agricultural pests in many cropping systems worldwide. Growers rely on the use of insecticides to control this pest. However, some i...The whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most devastating agricultural pests in many cropping systems worldwide. Growers rely on the use of insecticides to control this pest. However, some insecticides do not reduce the feeding of B. tabaci fast enough to prevent the direct and indirect damage produced by this insect. The effect of a new insecticide, cyantraniliprole 10OD (CyazypyrTM), on the feeding of B. tabaci adults, was studied under laboratory conditions. Cyantraniliprole 10OD is an insecticide that belongs to the IRAC Group 28 with a new mode of action for sucking insects, which provides rapid feeding cessation by impairing muscle function, resulting in reduced transmission of important insect vectored crop diseases. Laboratory experiments were conducted to determine the effect of cyantraniliprole along with some other commercially available insecticides on the feeding of B. tabaci adults by measuring the excretion of honeydew as an indirect assessment of insect feeding. In these experiments, cyantraniliprole resulted in significantly higher reduction of honeydew excretion (64.0%) by Q biotype B. tabaci adults during the first 30 minutes of exposure than diafenthiuron, triazophos, acetamiprid and spiromesifen, with all treatments having no adult mortality. Observations between 1 and 48 hours after exposure indicated that cyantraniliprole had numerically higher or similar reduction in honeydew production as the other insecticides, but by 48 hours (mid and high rate) and 96 hours (high rate) of exposure, cyantraniliprole had significantly higher reduction of honeydew excretion than all other insecticides tested. Low adult mortality was observed during first 24 hours of exposure in all treatments. Cyantraniliprole resulted in numerical or significantly higher adult mortality than all other treatments at the later observation intervals (72 - 96 hours). The higher reduction in honeydew excretion by cyantraniliprole appeared to be related to faster feeding cessation during the initial 展开更多
Since the emergence of cancer nanomedicine, researchers have had intense interest in developing nanoparticles （NPs） that can specifically target diseased sites while avoiding healthy tissue to mitigate the off-targe...Since the emergence of cancer nanomedicine, researchers have had intense interest in developing nanoparticles （NPs） that can specifically target diseased sites while avoiding healthy tissue to mitigate the off-target effects seen with conventional treatments like chemotherapy. Initial endeavors focused on the bioconjugation of targeting agents to NPs, and more recently, researchers have begun to develop biomimetic NP platforms that can avoid immune recognition to maximally accumulate in tumors. In this review, we describe the advantages and limitations of each of these targeting strategies. First, we review developments in bioconjugation strategies, where NPs are coated with biomolecules such as antibodies, aptamers, peptides, and small molecules to enable cell-specific binding. While bioconjugated NPs offer many exciting features and have improved pharmacokinetics and biodistribution relative to unmodified NPs, they are still recognized by the body as ＂foreign＂, resulting in their clearance by the mononuclear phagocytic system （MPS）. To overcome this limitation, researchers have recently begun to investigate biomimetic approaches that can hide NPs from immune recognition and reduce clearance by the MPS. These biomimetic NPs fall into two distinct categories： synthetic NPs that present naturally occurring structures, and NPs that are completely disguised by natural structures. Overall bioconjugated and biomimetic NPs have substantial potential to improve upon conventional treatments by reducing off-target effects through site-specific delivery. and they show great promise for future standards of care. Here, we provide a summary of each strategy, discuss considerations for their design moving forward, and highlight their potential clinical impact on cancer therapy.展开更多
Starch is the major component in maize kernels,providing a stable carbohydrate source for humans and livestock as well as raw material for the biofuel industry.Increasing maize kernel starch content will help meet ind...Starch is the major component in maize kernels,providing a stable carbohydrate source for humans and livestock as well as raw material for the biofuel industry.Increasing maize kernel starch content will help meet industry demands and has the potential to increase overall yields.We developed a pair of maize near-isogenic lines（NILs） with different alleles for a starch quantitative trait locus on chromosome 3（q HS3）, resulting in different kernel starch content. To investigate the candidate genes for q HS3 and elucidate their effects on starch metabolism, RNA-Seq was performed for the developing kernels of the NILs at 14 and 21 d after pollination（DAP）. Analysis of genomic and transcriptomic data identified 76 genes with nonsynonymous single nucleotide polymorphisms and 384 differentially expressed genes（DEGs） in the in trogressed fragment, including a hexokinase gene, Zm HXK3 a, which catalyzes the conversion of glucose to glucose-6-phosphate and may play a key role instarch metabolism. The expression pattern of all DEGs in starch metabolism shows that altered expression of the candidate genes for q HS3 promoted starch synthesis,with positive consequences for kernel starch content. These results expand the current understanding of starch biosynthesis and accumulation in maize kernels and provide potential candidate genes to increase starch content.展开更多
Carbon nanotube sorting,i.e.,the separation of a mixture of tubes into different electronic types and further into species with a specifi c chirality,is a fascinating problem of both scientifi c and technological impo...Carbon nanotube sorting,i.e.,the separation of a mixture of tubes into different electronic types and further into species with a specifi c chirality,is a fascinating problem of both scientifi c and technological importance.It is one of those problems that are easy to describe but diffi cult to solve.Single-stranded DNA forms stable complexes with carbon nanotubes and disperses them effectively in water.A particular DNA sequence of alternating guanine(G)and thymine(T)nucleotides((GT)n,with n=10 to 45)self-assembles into an ordered supramolecular structure around an individual nanotube,in such a way that the electrostatic properties of the DNA-carbon nanotube hybrid depend on tube structure,enabling nanotube separation by anion-exchange chromatography.This review provides a summary of the separation of metallic and semiconducting tubes,and purification of single(n,m)tubes using the DNA-wrapping approach.We will present our current understanding of the DNA-carbon nanotube hybrid structure and separation mechanisms,and predict future developments of the DNA-based approach.展开更多
The utility of a next generation biosynthetic bacterial 6-phytase(PhyG)in restoring bone ash,bone phosphorus(P)content and performance in piglets depleted in P was evaluated.A total of 9 treatments were tested as foll...The utility of a next generation biosynthetic bacterial 6-phytase(PhyG)in restoring bone ash,bone phosphorus(P)content and performance in piglets depleted in P was evaluated.A total of 9 treatments were tested as follows.Treatment 1,a negative control(NC)diet;treatments 2,3,4,NC supplemented with 250,500 or 1,000 FTU/kg of PhyG;treatments 5,6,NC supplemented with 500 or 1,000 FTU/kg of a commercial Buttiauxella sp phytase(PhyB);treatments 7,8,9,NC supplemented with monocalcium phosphate(MCP)to provide 0.7,1.4 and 1.8 g/kg digestible P,equating to a digestible P content of 1.8,2.5 and 2.9 g/kg.The latter constituting the positive control(PC)diet with adequate P and calcium(Ca).The NC was formulated without inorganic P(1.1 g digestible P/kg)and reduced in Ca(5.0 g/kg).Additional limestone was added to treatments 7 to 9 to maintain Ca-to-P ratio between 1.2 and 1.3.A total of 162 crossed Pietrain x(Large White×Landrace)21-d-old piglets(50%males and 50%females)were fed adaptation diets until 42 d old and then assigned to pens with 2 pigs/pen and 9 pens/treatment in a completely randomized block design.Piglets were fed mash diets based on corn and soybean meal ad libitum for 28 d.At the end of the study,one piglet perpen was euthanized and the right feet collected for determination of bone strength,bone ash and mineral content.Compared with the PC,the NC group had reduced average daily gain(ADG)and increased feed conversion ratio(FCR)during all growth phases and overall,and at d 28(70 d old)NC pigs had bones with reduced ash,Ca and P content(P<0.05).The PhyG at 250 FTU/kg improved bone ash vs.NC.Increasing PhyG dose linearly or quadratically improved bone ash,ADG and FCR(P<0.05).At>500 FTU/kg,both PhyG and PhyB maintained ADG and FCR equivalent to PC.Linear regression analysis was done to compare the measured response parameters to increasing digestible P from MCP.Based on this analysis it was shown that PhyG and PhyB at 1,000 FTU/kg could replace 1,83 and 1.66 g/kg digestible P from MCP in the diet,respectively,on a展开更多
AIM: To determine the efficacy of probiotic supplementation on intestinal transit time(ITT) in adults and to identify factors that influence these outcomes. METHODS: We conducted a systematic review of randomized cont...AIM: To determine the efficacy of probiotic supplementation on intestinal transit time(ITT) in adults and to identify factors that influence these outcomes. METHODS: We conducted a systematic review of randomized controlled trials of probiotic supplementation that measured ITT in adults. Study quality was assessed using the Jadad scale. A random effects meta-analysis was performed with standardized mean difference(SMD) of ITT between probiotic and control groups as the primary outcome. Meta-regression and subgroup analyses examined the impact of moderator variables on SMD of ITT.RESULTS: A total of 15 clinical trials with 17 treatment effects representing 675 subjects were included in this analysis. Probiotic supplementation was moderately efficacious in decreasing ITT compared to control, with an SMD of 0.38(95%CI: 0.23-0.53, P < 0.001). Subgroup analyses demonstrated statistically greater reductions in ITT with probiotics in subjects with vs without constipation(SMD: 0.57 vs 0.22, P < 0.01) and in studies with high vs low study quality(SMD: 0.45 vs 0.00, P = 0.01). Constipation(R^2 = 38%, P < 0.01), higher study quality(R^2 = 31%, P = 0.01), older age(R^2 = 27%, P = 0.02), higher percentage of female subjects(R^2 = 26%, P = 0.02), and fewer probiotic strains(R^2 = 20%, P < 0.05) were predictive of decreased ITT with probiotics in meta-regression. Medium to large treatment effects were identified with B. lactis HN019(SMD: 0.67, P < 0.001) and B. lactis DN-173 010(SMD: 0.54, P < 0.01) while other probiotic strains yielded negligible reductions in ITT relative to control.CONCLUSION: Probiotic supplementation is moderately efficacious for reducing ITT in adults. Probiotics were most efficacious in constipated subjects, when evaluated in high-quality studies, and with certain probiotic strains.展开更多
Sorghum （Sorghum bicolor） has high levels of starch, sugar, and fiber and is one of the most important energy crops in the world. Insect damage is one of the challenges that impacts sorghum biomass production. There...Sorghum （Sorghum bicolor） has high levels of starch, sugar, and fiber and is one of the most important energy crops in the world. Insect damage is one of the challenges that impacts sorghum biomass production. There are at least 150 insect species that can infest sorghum varieties worldwide. These insects can complete several generations within a growing season, they target various parts of sorghum plants at devel- opmental stages, and they cause significant biomass losses. Genetic research has revealed the existence of resistant genetics in sorghum and insect tolerant sorghum varieties have been identified. Various control methods have been developed, yet more effective management is needed for increasing sorghum biomass production. Although there are no transgenic sorghum products on the market yet, biotechnology has been recognized as an important tool for controlling insect pests and increasing sorghum production.展开更多
The unique composition of milk makes this basic foodstuff into an exceptional raw material for the production of new ingredients with desired properties and diverse applications in the food industry. The fractionation...The unique composition of milk makes this basic foodstuff into an exceptional raw material for the production of new ingredients with desired properties and diverse applications in the food industry. The fractionation of milk is the key in the development of those ingredients and products;hence continuous research and development on this field, especially various levels of fractionation and separation by filtration, have been carried out. This review focuses on the production of milk fractions as well as their particular properties, applications and processes that increase their exploitation. Whey proteins and caseins from the protein fraction are excellent emulsifiers and protein supplements. Besides, they can be chemically or enzymatically modified to obtain bioactive peptides with numerous functional and nutritional properties. In this context, valorization techniques of cheese-whey proteins, by-product of dairy industry that constitutes both economic and environmental problems, are being developed. Phospholipids from the milk fat fraction are powerful emulsifiers and also have exclusive nutraceutical properties. In addition, enzyme modification of milk phospholipids makes it possible to tailor emulsifiers with particular properties. However, several aspects remain to be overcome;those refer to a deeper understanding of the healthy, functional and nutritional properties of these new ingredients that might be barriers for its use and acceptability. Additionally, in this review, alternative applications of milk constituents in the non-food area such as in the manufacture of plastic materials and textile fibers are also introduced. The unmet needs, the cross-fertilization in between various protein domains,the carbon footprint requirements, the environmental necessities, the health and wellness new demand, etc., are dominant factors in the search for innovation approaches;these factors are also outlining the further innovation potential deriving from those “apparent” constrains obliging science and technology展开更多
After setting the ground of the quantum innovation potential of biosourced entities and outlining the inventive spectrum of adjacent technologies that can derive from those, the current review highlights, with the sup...After setting the ground of the quantum innovation potential of biosourced entities and outlining the inventive spectrum of adjacent technologies that can derive from those, the current review highlights, with the support of Bigger Data approaches, and a fairly large number of articles, more than 250 and 10,000 patents, the following. It covers an overview of biosourced chemicals and materials, mainly biomonomers, biooligomers and biopolymers;these are produced today in a way that allows reducing the fossil resources depletion and dependency, and obtaining environmentally-friendlier goods in a leaner energy consuming society. A process with a realistic productivity is underlined thanks to the implementation of recent and specifically effective processes where engineered microorganisms are capable to convert natural non-fossil goods, at industrial scale, into fuels and useful high-value chemicals in good yield. Those processes, further detailed, integrate: metabolic engineering involving 1) system biology, 2) synthetic biology and 3) evolutionary engineering. They enable acceptable production yield and productivity, meet the targeted chemical profiles, minimize the consumption of inputs, reduce the production of by-products and further diminish the overall operation costs. As generally admitted the properties of most natural occurring biopolymers (e.g., starch, poly (lactic acid), PHAs.) are often inferior to those of the polymers derived from petroleum;blends and composites, exhibiting improved properties, are now successfully produced. Specific attention is paid to these aspects. Then further evidence is provided to support the important potential and role of products deriving from the biomass in general. The need to enter into the era of Bigger Data, to grow and increase the awareness and multidimensional role and opportunity of biosourcing serves as a conclusion and future prospects. Although providing a large reference database, this review is largely initiatory, therefore not mimicking previous classic revie展开更多
Mites belonging to the family Phytoseiidae are the most important and most widely studied among predatory mites of phytophagous mites. The phytophagous mites Brevipalpus phoenicis (Geijskes, 1939) (Tenuipalpidae) and ...Mites belonging to the family Phytoseiidae are the most important and most widely studied among predatory mites of phytophagous mites. The phytophagous mites Brevipalpus phoenicis (Geijskes, 1939) (Tenuipalpidae) and Oligonychus ilicis (McGregor, 1917) (Tetranychidae) on coffee (Coffea spp.), are frequently found in combination with the predaceous mites Iphiseiodes zuluagai Denmark & Muma, 1972;Euseius alatus DeLeon, 1966 and Amblyseius herbicolus (Chant, 1959) (Acari: Phytoseiidae), among others. The purpose of this research was to study the effects of the product CyazypyrTM (cyantraniliprole 100 OD) on these three species of Phytoseiidae, relevant to coffee, citrus and other agricultural crops in Brazil, following standard laboratory procedures. Mated female mites were exposed to fresh-dried residues on a glass surface, with 8 treatments, 5 mites per glass plate and 6 replicates, in a completely randomized experimental design. Each test lasted eight days, with a daily count of the surviving females and of eggs laid. CyazypyrTM, in all tested doses (75, 100, 125, 150, 175 and 200 g a.i./ha), was selective for the studied species, A. herbicolus, I. zuluagai, and E. alatus. Overall the treatments resulted in low mortality rates and negligible impact on the reproduction. Therefore, based on IOBC standards, CyazypyrTMcan be classified as not harmful (class 1) or slightly harmful (class 2), comparable to the agrochemical TalentoTM (hexythiazox 500 WP-12 g a.i./ha) equivalent to a harmless standard of selectivity in the laboratory. CyazypyrTM is therefore a complement to programs of integrated pest management, to preserve the populations of predatory mites in crops of coffee and citrus, among others, in Brazil.展开更多
文摘The wall of an expanding plant cell consists primarily of cellulose microfibrils embedded in a matrix of hemicellulosic and pectic polysaccharides along with small amounts of structural and enzymatic proteins. Matrix polysaccharides are synthesized in the Golgi and exported to the cell wall by exocytosis, where they intercalate among cellulose microfibrils, which are made at the plasma membrane and directly deposited into the cell wall. Involvement of Golgi glucan synthesis in auxin-induced cell expansion has long been recognized; however, only recently have the genes corresponding to glucan synthases been identified. Biochemical purification was unsuccessful because of the labile nature and very low abundance of these enzymes. Mutational genetics also proved fruitless. Expression of candidate genes identified through gene expression profiling or comparative genomics in heterologous systems followed by functional characterization has been relatively successful. Several genes from the cellulose synthase-like （Csl） family have been found to be involved in the synthesis of various hemicellulosic glycans. The usefulness of this approach, however, is limited to those enzymes that probably do not form complexes consisting of unrelated proteins. Nonconventional approaches will continue to incrementally unravel the mechanisms of Golgi polysaccharide biosynthesis.
文摘Sedimentation based processes are widely used in industry to separate particles from a liquid phase. Since the advent of the ＂Nanoworld＂ the demand for effective separation technologies has rapidly risen, calling for the development of new separation concepts, one of which lies in hybrid separation using the superposition of a magnetic field for magnetic particles. Possible product portfolio of such separation consists of pigment production, nanomagnetics production for electronics and bio separation, A promising step in that direction is magnetic field enhanced cake filtration, which has by now progressed from batch to continuous ooeration. In sedimentation processes in a mass force field the settling behaviour of particles strongly depends on physico-chemical properties, concentration and size distribution of the particles. By adjusting the pH, the interparticle forces, in particular the electrostatic repulsion, can be manipulated. For remanent magnetic particles such as magnetite, pre-treatment in a magnetic field could lead to a change of interparticle interactions. By magnetizing the particles apart from van der Waals attraction and electrostatic repulsion, an additional potential is induced, the magnetic attraction, which could easily dominate the other potentials and result in agglomeration in the primary minimum. By sedimentation analysis, a wide spectrum of parameters like pH, magnetic field strength and concentration have been investigated. The results show a strong increase of sedimentation velocity by magnetic flocculation of the raw suspension. This leads to a rise in throughput due to the acceleration of sedimentation kinetics by imparting a non-chemical interaction to the physico-chemical properties in the feed stream of the separation apparatus.
基金supported by the National Science Foundation Plant Genome Research Program, grant no. IOS-1025976 to DMB
文摘During daylight, plants produce excess photo- synthates, including sucrose, which is temporarily stored in the vacuole. At night, plants remobilize sucrose to sustain metabolism and growth. Based on homology to other sucrose transporter （SUT） proteins, we hypothesized the maize （Zea mays） SUCROSE TRANSPORTER2 （ZmSUT2） protein functions as a sucrose/H^＋ symporter on the vacuolar membrane to export transiently stored sucrose. To understand the biological role of ZmSut2, we examined its spatial and temporal gene expression, determined the protein subcellular localization, and characterized loss-of- function mutations. ZmSut2 mRNA was ubiquitously expressed and exhibited diurnal cycling in transcript abundance. Expressing a translational fusion of ZmSUT2 fused to a red fluorescent protein in maize mesophyll cell protoplasts revealed that the protein localized to the tonoplast. Under field conditions, zmsut2 mutant plants grew slower, possessed smaller tassels and ears, and produced fewer kernels when compared to wild-type siblings, zmsut2 mutants also accumulated two-fold more sucrose, glucose, and fructose as well as starch in source leaves compared to wild type. These findings suggest （i） ZmSUT2 functions to remobilize sucrose out of the vacuole for subsequent use in growing tissues; and （ii） its function provides an important contribution to maize development and agronomic yield.
文摘This review provides a critical overview of the recent methods and processes developed for the production of cellulose nanoparticles with controlled morphology, structure and properties, and also sums up (1) the processes for the chemical modifications of these particles in order to prevent their re-aggregation during spray-drying procedures and to increase their reactivity, (2) the recent processes involved in the production of nanostructured biomaterials and composites. The structural and physical properties of those nanocelluloses, combined with their biodegradability, make them materials of choice in the very promising area of nanotechnology, likely subject to major commercial successes in the context of green chemistry. With a prospective and pioneering approach to the subject matter, various laboratories involved in this domain have developed bio-products now almost suitable to industrial applications;although some important steps remain to be overcome, those are worth been reviewed and supplemented. At this stage, several pilot units and demonstration plants have been built to improve, optimize and scale-up the processes developed at laboratory scale. Industrial reactors with suitable environment and modern control equipment are to be expected within that context. This review shall bring the suitable processing dimension that may be needed now, given the numerous reviews outlining the product potential attributes. An abundant literature database, close to 250 publications and patents, is provided, consolidating the various research and more practical angles.
文摘AIM: To determine the efficacy of probiotic supplementation on intestinal transit time (ITT) and to identify factors that influence these outcomes. METHODS: A systematic review of randomized controlled trials (RCTs) of probiotic supplementation that measured ITT in adults was conducted by searching MEDLINE and EMBASE using relevant combinations. Main search limits included RCTs of probiotic supplementation in healthy or constipated adults that measured ITT. Study quality was assessed using the Jadad scale. A random effects meta-analysis was performed with standardized mean difference (SMD) of ITT between probiotic and control groups as the primary outcome. Meta-regression and subgroup analyses were conducted to examine the impact of moderator variables on ITT SMD. RESULTS: A total of 11 clinical trials with 13 treatment effects representing 464 subjects were included in this analysis. Probiotic supplementation was associated with decreased ITT in relation to controls, with an SMD of 0.40 (95%CI: 0.20-0.59, P < 0.001). Constipation (r 2 = 39%, P = 0.01), higher mean age (r 2 = 27%, P = 0.03), and higher percentage of female subjects (r 2 = 23%, P < 0.05) were predictive of decreased ITT with probiotics in meta-regression. Subgroup analyses demonstrated statistically greater reductions in ITT with probiotics in subjects with vs without constipation and in older vs younger subjects [both SMD: 0.59 (95%CI: 0.39-0.79) vs 0.17 (95%CI: -0.08-0.42), P = 0.01]. Medium to large treatment effects were identified with Bifidobacterium Lactis (B. lactis ) HN019 (SMD: 0.72, 95%CI: 0.27-1.18, P < 0.01) and B. lactis DN-173 010 (SMD: 0.54, 95%CI: 0.15-0.94, P < 0.01) while other single strains and combination products yielded small treatment effects. CONCLUSION: Overall, short-term probiotic supplementation decreases ITT with consistently greater treatment effects identified in constipated or older adults and with certain probiotic strains.
文摘AIM To determine the effects of Lactobacillus acidophilus NCFM on irritable bowel syndrome(IBS) symptoms and quality of life(Qo L).METHODS In this randomized triple-blind trial, adult IBS volunteerswho were recruited according to Rome Ⅲ criteria received 109 or 1010 colony-forming units of NCFM or placebo daily for 12 wk. IBS Symptom Severity Score(IBS-SSS), which constituted the primary outcome, and secondary outcomes, including individual IBS symptoms, IBS-related QoL questionnaire, anxiety and depression, defecation frequency, and stool consistency, were assessed at baseline at the end of the 8-wk runin period, after 4 and 12 wk of intervention, and after a 4-wk washout.RESULTS A total of 340 of 391 randomized volunteers completed the trial. IBS-SSS improved over 12 wk of treatment in all treatment groups, decreasing by a mean ± SD of 44.0 ± 80.2, 50.8 ± 82.4, and 48.3 ± 72.2 in the placebo, active low-dose, and active high-dose groups, respectively. Similarly, secondary outcomes did not differ between treatment groups. However, in a post hoc analysis of volunteers with moderate to severe abdominal pain at baseline(VAS > 35/100), the treatment significantly reduced the sensation of abdominal pain. Pain scores fell by 20.8 ± 22.8, 29.4 ± 17.9, and 31.2 ± 21.9 in the placebo, active low-dose, and active high-dose groups, respectively(P value for placebo vs combined active doses = 0.0460).CONCLUSION NCFM alleviates moderate to severe abdominal pain, consistent with earlier observations of this strain mitigating visceral pain through increased analgesic receptor expression.
文摘In this study,an improved impedance tube test method is proposed to determine the sound absorption coefficients of materials at high frequencies up to 10 kHz.Specifically,a multi-modal decomposition method is used to measure the sound absorption coefficients above the cut-off frequency of plane waves in the impedance tube.During the measurement process,an array of microphones is placed in the circumferential and axial directions of the tube.Then,the first three acoustic circumferential modes are decomposed,and the corresponding axial incident and reflected waves at each mode are recorded by the array of microphones.The accuracy and feasibility of the proposed multi-modal decomposition method are validated by comparing the measurement results with those obtained using the conventional impedance tube method.
文摘The whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most devastating agricultural pests in many cropping systems worldwide. Growers rely on the use of insecticides to control this pest. However, some insecticides do not reduce the feeding of B. tabaci fast enough to prevent the direct and indirect damage produced by this insect. The effect of a new insecticide, cyantraniliprole 10OD (CyazypyrTM), on the feeding of B. tabaci adults, was studied under laboratory conditions. Cyantraniliprole 10OD is an insecticide that belongs to the IRAC Group 28 with a new mode of action for sucking insects, which provides rapid feeding cessation by impairing muscle function, resulting in reduced transmission of important insect vectored crop diseases. Laboratory experiments were conducted to determine the effect of cyantraniliprole along with some other commercially available insecticides on the feeding of B. tabaci adults by measuring the excretion of honeydew as an indirect assessment of insect feeding. In these experiments, cyantraniliprole resulted in significantly higher reduction of honeydew excretion (64.0%) by Q biotype B. tabaci adults during the first 30 minutes of exposure than diafenthiuron, triazophos, acetamiprid and spiromesifen, with all treatments having no adult mortality. Observations between 1 and 48 hours after exposure indicated that cyantraniliprole had numerically higher or similar reduction in honeydew production as the other insecticides, but by 48 hours (mid and high rate) and 96 hours (high rate) of exposure, cyantraniliprole had significantly higher reduction of honeydew excretion than all other insecticides tested. Low adult mortality was observed during first 24 hours of exposure in all treatments. Cyantraniliprole resulted in numerical or significantly higher adult mortality than all other treatments at the later observation intervals (72 - 96 hours). The higher reduction in honeydew excretion by cyantraniliprole appeared to be related to faster feeding cessation during the initial
文摘Since the emergence of cancer nanomedicine, researchers have had intense interest in developing nanoparticles （NPs） that can specifically target diseased sites while avoiding healthy tissue to mitigate the off-target effects seen with conventional treatments like chemotherapy. Initial endeavors focused on the bioconjugation of targeting agents to NPs, and more recently, researchers have begun to develop biomimetic NP platforms that can avoid immune recognition to maximally accumulate in tumors. In this review, we describe the advantages and limitations of each of these targeting strategies. First, we review developments in bioconjugation strategies, where NPs are coated with biomolecules such as antibodies, aptamers, peptides, and small molecules to enable cell-specific binding. While bioconjugated NPs offer many exciting features and have improved pharmacokinetics and biodistribution relative to unmodified NPs, they are still recognized by the body as ＂foreign＂, resulting in their clearance by the mononuclear phagocytic system （MPS）. To overcome this limitation, researchers have recently begun to investigate biomimetic approaches that can hide NPs from immune recognition and reduce clearance by the MPS. These biomimetic NPs fall into two distinct categories： synthetic NPs that present naturally occurring structures, and NPs that are completely disguised by natural structures. Overall bioconjugated and biomimetic NPs have substantial potential to improve upon conventional treatments by reducing off-target effects through site-specific delivery. and they show great promise for future standards of care. Here, we provide a summary of each strategy, discuss considerations for their design moving forward, and highlight their potential clinical impact on cancer therapy.
基金supported by the National Natural Science Foundation of China (31421005)International Cooperation in Science and Technology Project in China (2014DFG31690)DuPont Pioneer
文摘Starch is the major component in maize kernels,providing a stable carbohydrate source for humans and livestock as well as raw material for the biofuel industry.Increasing maize kernel starch content will help meet industry demands and has the potential to increase overall yields.We developed a pair of maize near-isogenic lines（NILs） with different alleles for a starch quantitative trait locus on chromosome 3（q HS3）, resulting in different kernel starch content. To investigate the candidate genes for q HS3 and elucidate their effects on starch metabolism, RNA-Seq was performed for the developing kernels of the NILs at 14 and 21 d after pollination（DAP）. Analysis of genomic and transcriptomic data identified 76 genes with nonsynonymous single nucleotide polymorphisms and 384 differentially expressed genes（DEGs） in the in trogressed fragment, including a hexokinase gene, Zm HXK3 a, which catalyzes the conversion of glucose to glucose-6-phosphate and may play a key role instarch metabolism. The expression pattern of all DEGs in starch metabolism shows that altered expression of the candidate genes for q HS3 promoted starch synthesis,with positive consequences for kernel starch content. These results expand the current understanding of starch biosynthesis and accumulation in maize kernels and provide potential candidate genes to increase starch content.
基金Work conducted in our lab is supported by DuPont and US National Science Foundation.
文摘Carbon nanotube sorting,i.e.,the separation of a mixture of tubes into different electronic types and further into species with a specifi c chirality,is a fascinating problem of both scientifi c and technological importance.It is one of those problems that are easy to describe but diffi cult to solve.Single-stranded DNA forms stable complexes with carbon nanotubes and disperses them effectively in water.A particular DNA sequence of alternating guanine(G)and thymine(T)nucleotides((GT)n,with n=10 to 45)self-assembles into an ordered supramolecular structure around an individual nanotube,in such a way that the electrostatic properties of the DNA-carbon nanotube hybrid depend on tube structure,enabling nanotube separation by anion-exchange chromatography.This review provides a summary of the separation of metallic and semiconducting tubes,and purification of single(n,m)tubes using the DNA-wrapping approach.We will present our current understanding of the DNA-carbon nanotube hybrid structure and separation mechanisms,and predict future developments of the DNA-based approach.
文摘The utility of a next generation biosynthetic bacterial 6-phytase(PhyG)in restoring bone ash,bone phosphorus(P)content and performance in piglets depleted in P was evaluated.A total of 9 treatments were tested as follows.Treatment 1,a negative control(NC)diet;treatments 2,3,4,NC supplemented with 250,500 or 1,000 FTU/kg of PhyG;treatments 5,6,NC supplemented with 500 or 1,000 FTU/kg of a commercial Buttiauxella sp phytase(PhyB);treatments 7,8,9,NC supplemented with monocalcium phosphate(MCP)to provide 0.7,1.4 and 1.8 g/kg digestible P,equating to a digestible P content of 1.8,2.5 and 2.9 g/kg.The latter constituting the positive control(PC)diet with adequate P and calcium(Ca).The NC was formulated without inorganic P(1.1 g digestible P/kg)and reduced in Ca(5.0 g/kg).Additional limestone was added to treatments 7 to 9 to maintain Ca-to-P ratio between 1.2 and 1.3.A total of 162 crossed Pietrain x(Large White×Landrace)21-d-old piglets(50%males and 50%females)were fed adaptation diets until 42 d old and then assigned to pens with 2 pigs/pen and 9 pens/treatment in a completely randomized block design.Piglets were fed mash diets based on corn and soybean meal ad libitum for 28 d.At the end of the study,one piglet perpen was euthanized and the right feet collected for determination of bone strength,bone ash and mineral content.Compared with the PC,the NC group had reduced average daily gain(ADG)and increased feed conversion ratio(FCR)during all growth phases and overall,and at d 28(70 d old)NC pigs had bones with reduced ash,Ca and P content(P<0.05).The PhyG at 250 FTU/kg improved bone ash vs.NC.Increasing PhyG dose linearly or quadratically improved bone ash,ADG and FCR(P<0.05).At>500 FTU/kg,both PhyG and PhyB maintained ADG and FCR equivalent to PC.Linear regression analysis was done to compare the measured response parameters to increasing digestible P from MCP.Based on this analysis it was shown that PhyG and PhyB at 1,000 FTU/kg could replace 1,83 and 1.66 g/kg digestible P from MCP in the diet,respectively,on a
文摘AIM: To determine the efficacy of probiotic supplementation on intestinal transit time(ITT) in adults and to identify factors that influence these outcomes. METHODS: We conducted a systematic review of randomized controlled trials of probiotic supplementation that measured ITT in adults. Study quality was assessed using the Jadad scale. A random effects meta-analysis was performed with standardized mean difference(SMD) of ITT between probiotic and control groups as the primary outcome. Meta-regression and subgroup analyses examined the impact of moderator variables on SMD of ITT.RESULTS: A total of 15 clinical trials with 17 treatment effects representing 675 subjects were included in this analysis. Probiotic supplementation was moderately efficacious in decreasing ITT compared to control, with an SMD of 0.38(95%CI: 0.23-0.53, P < 0.001). Subgroup analyses demonstrated statistically greater reductions in ITT with probiotics in subjects with vs without constipation(SMD: 0.57 vs 0.22, P < 0.01) and in studies with high vs low study quality(SMD: 0.45 vs 0.00, P = 0.01). Constipation(R^2 = 38%, P < 0.01), higher study quality(R^2 = 31%, P = 0.01), older age(R^2 = 27%, P = 0.02), higher percentage of female subjects(R^2 = 26%, P = 0.02), and fewer probiotic strains(R^2 = 20%, P < 0.05) were predictive of decreased ITT with probiotics in meta-regression. Medium to large treatment effects were identified with B. lactis HN019(SMD: 0.67, P < 0.001) and B. lactis DN-173 010(SMD: 0.54, P < 0.01) while other probiotic strains yielded negligible reductions in ITT relative to control.CONCLUSION: Probiotic supplementation is moderately efficacious for reducing ITT in adults. Probiotics were most efficacious in constipated subjects, when evaluated in high-quality studies, and with certain probiotic strains.
基金supported by Pioneer Hi-Bred International Inc.,A DuPont Company
文摘Sorghum （Sorghum bicolor） has high levels of starch, sugar, and fiber and is one of the most important energy crops in the world. Insect damage is one of the challenges that impacts sorghum biomass production. There are at least 150 insect species that can infest sorghum varieties worldwide. These insects can complete several generations within a growing season, they target various parts of sorghum plants at devel- opmental stages, and they cause significant biomass losses. Genetic research has revealed the existence of resistant genetics in sorghum and insect tolerant sorghum varieties have been identified. Various control methods have been developed, yet more effective management is needed for increasing sorghum biomass production. Although there are no transgenic sorghum products on the market yet, biotechnology has been recognized as an important tool for controlling insect pests and increasing sorghum production.
文摘The unique composition of milk makes this basic foodstuff into an exceptional raw material for the production of new ingredients with desired properties and diverse applications in the food industry. The fractionation of milk is the key in the development of those ingredients and products;hence continuous research and development on this field, especially various levels of fractionation and separation by filtration, have been carried out. This review focuses on the production of milk fractions as well as their particular properties, applications and processes that increase their exploitation. Whey proteins and caseins from the protein fraction are excellent emulsifiers and protein supplements. Besides, they can be chemically or enzymatically modified to obtain bioactive peptides with numerous functional and nutritional properties. In this context, valorization techniques of cheese-whey proteins, by-product of dairy industry that constitutes both economic and environmental problems, are being developed. Phospholipids from the milk fat fraction are powerful emulsifiers and also have exclusive nutraceutical properties. In addition, enzyme modification of milk phospholipids makes it possible to tailor emulsifiers with particular properties. However, several aspects remain to be overcome;those refer to a deeper understanding of the healthy, functional and nutritional properties of these new ingredients that might be barriers for its use and acceptability. Additionally, in this review, alternative applications of milk constituents in the non-food area such as in the manufacture of plastic materials and textile fibers are also introduced. The unmet needs, the cross-fertilization in between various protein domains,the carbon footprint requirements, the environmental necessities, the health and wellness new demand, etc., are dominant factors in the search for innovation approaches;these factors are also outlining the further innovation potential deriving from those “apparent” constrains obliging science and technology
文摘After setting the ground of the quantum innovation potential of biosourced entities and outlining the inventive spectrum of adjacent technologies that can derive from those, the current review highlights, with the support of Bigger Data approaches, and a fairly large number of articles, more than 250 and 10,000 patents, the following. It covers an overview of biosourced chemicals and materials, mainly biomonomers, biooligomers and biopolymers;these are produced today in a way that allows reducing the fossil resources depletion and dependency, and obtaining environmentally-friendlier goods in a leaner energy consuming society. A process with a realistic productivity is underlined thanks to the implementation of recent and specifically effective processes where engineered microorganisms are capable to convert natural non-fossil goods, at industrial scale, into fuels and useful high-value chemicals in good yield. Those processes, further detailed, integrate: metabolic engineering involving 1) system biology, 2) synthetic biology and 3) evolutionary engineering. They enable acceptable production yield and productivity, meet the targeted chemical profiles, minimize the consumption of inputs, reduce the production of by-products and further diminish the overall operation costs. As generally admitted the properties of most natural occurring biopolymers (e.g., starch, poly (lactic acid), PHAs.) are often inferior to those of the polymers derived from petroleum;blends and composites, exhibiting improved properties, are now successfully produced. Specific attention is paid to these aspects. Then further evidence is provided to support the important potential and role of products deriving from the biomass in general. The need to enter into the era of Bigger Data, to grow and increase the awareness and multidimensional role and opportunity of biosourcing serves as a conclusion and future prospects. Although providing a large reference database, this review is largely initiatory, therefore not mimicking previous classic revie
基金For DuPont do Brasil S.A.-Agricultura e Nutricao for the financial supportCNPq and INCT do CaféCNPq-Fapemig for the fellowship.
文摘Mites belonging to the family Phytoseiidae are the most important and most widely studied among predatory mites of phytophagous mites. The phytophagous mites Brevipalpus phoenicis (Geijskes, 1939) (Tenuipalpidae) and Oligonychus ilicis (McGregor, 1917) (Tetranychidae) on coffee (Coffea spp.), are frequently found in combination with the predaceous mites Iphiseiodes zuluagai Denmark & Muma, 1972;Euseius alatus DeLeon, 1966 and Amblyseius herbicolus (Chant, 1959) (Acari: Phytoseiidae), among others. The purpose of this research was to study the effects of the product CyazypyrTM (cyantraniliprole 100 OD) on these three species of Phytoseiidae, relevant to coffee, citrus and other agricultural crops in Brazil, following standard laboratory procedures. Mated female mites were exposed to fresh-dried residues on a glass surface, with 8 treatments, 5 mites per glass plate and 6 replicates, in a completely randomized experimental design. Each test lasted eight days, with a daily count of the surviving females and of eggs laid. CyazypyrTM, in all tested doses (75, 100, 125, 150, 175 and 200 g a.i./ha), was selective for the studied species, A. herbicolus, I. zuluagai, and E. alatus. Overall the treatments resulted in low mortality rates and negligible impact on the reproduction. Therefore, based on IOBC standards, CyazypyrTMcan be classified as not harmful (class 1) or slightly harmful (class 2), comparable to the agrochemical TalentoTM (hexythiazox 500 WP-12 g a.i./ha) equivalent to a harmless standard of selectivity in the laboratory. CyazypyrTM is therefore a complement to programs of integrated pest management, to preserve the populations of predatory mites in crops of coffee and citrus, among others, in Brazil.
