A large fire of 233 ha in Huascarán National Park in Peru provided an opportunity to compare plant and bird responses in burned and nearby unburned zones of the puna. Heights and live diameters of flagship Puya r...A large fire of 233 ha in Huascarán National Park in Peru provided an opportunity to compare plant and bird responses in burned and nearby unburned zones of the puna. Heights and live diameters of flagship Puya raimondii rosettes(assigned to four broad developmental phases), plant communities(66 species in 24 families and nine growth forms) and bird communities(77 species in six trophic guilds) were monitored after the fire. Although no mortality was observed, Puya raimondii plants were affected by the fire, losing approximately 60% of their photosynthetic area across all developmental phases, but recovered quickly during the first two years after fire. The comparison of Puya rosette recovery after fire was complicated by the changes in live rosette diameter for unburned plants, which showed plasticity of photosynthetic area linked to seasonal and annual fluctuations in precipitation in this relatively dry environment(decreased by 26% for mature adult plants over the study period). Fire caused an immediate change in the density, biomass and composition of vegetation. Although the species present remained similar, their abundances changed significantly immediately after the fire, with notable reductions in dominant tussock grasses. This provided opportunities for other plants, resulting in higher postfire diversity of plant species, genera, families and growth forms. In turn, the changes in vegetation after fire affected the composition of birds according to their trophic guild. Granivores largely disappeared,generalists were mostly unaffected, and other guilds showed a more complex response. As the vegetation recovered, most displaced birds returned within approximately one year.展开更多
The full-field multiaxial strain measurement is highly desired for application of structural monitoring but still challenging,especially when the manufacturing and assembling for largearea sensing devices is quite dif...The full-field multiaxial strain measurement is highly desired for application of structural monitoring but still challenging,especially when the manufacturing and assembling for largearea sensing devices is quite difficult.Compared with the traditional procedure of gluing commercial strain gauges on the structure surfaces for strain monitoring,the recently developed Direct-Ink-Writing(DIW)technology provides a feasible way to directly print sensors on the structure.However,there are still crucial issues in the design and printing strategies to be probed and improved.Therefore,in this work,we propose an integrated strategy from layered circuit scheme to rapid manufacturing of strain rosette sensor array based on the DIW technology.Benefit from the innovative design with simplified circuit layout and the advantages of DIW for printing multilayer structures,here we achieve optimization design principle for strain rosette sensor array with scalable circuit layout,which enable a hierarchical printing strategy for multiaxial strain monitoring in large scale or multiple domains.The strategy is highly expected to adapt for the emerging requirement in various applications such as integrated soft electronics,nondestructive testing and small-batch medical devices.展开更多
The present comparative review discusses conservation of early evolutionary, relic genetics in the genome of man, which determine two different mechanistic reductive division systems expressed by normal, human diploid...The present comparative review discusses conservation of early evolutionary, relic genetics in the genome of man, which determine two different mechanistic reductive division systems expressed by normal, human diploid cells. The divisions were orderly and segregated genomes reductively to near-diploid daughter cells, which showed gain of a proliferative advantage (GPA) over cells of origin. This fact of GPA expression is a fundamental requirement for initiation of tumorigenesis. The division systems were responses to a carcinogen-free induction system, consisting of short (1 - 3 days) exposures of young cells to nutritional deprivation of amino acid glutamine (AAD). In recovery growth (2 - 4 days) endo-tetra/ochtoploid cells and normal diploid metaphase cells demonstrated chromosomal reductive divisions to respectively heterozygous and homozygous altered daughter cells. Both division systems showed co-segregating whole complements, which for reduction of the diploid metaphases could only arise from gonomeric-based autonomous behavior of maternal and paternal (mat/pat) genomes. The timely associated appearance with these latter divisions was fast growing small-cells (1/2 volume-size reduced from normal diploidy), which became homozygous from haploid, genomic doubling. Both reductive divisions thus produced genome altered progeny cells with GPA, which was associated with pre-cancer-like cell-phenotypic changes. Since both “undesirable” reductive divisions expressed orderly division sequences, their genetic controls were assumed to be “old genetics”, evolutionarily conserved in the genome of man. Support for this idea was a search for evidential material in the evolutionary record from primeval time, when haploid organisms were established. The theory was that endopolyploid and gonomery-based reductive divisions relieved the early eukaryotic organisms from accidental, non-proliferative diploidy and polyploidy, bringing the organism back to vegetative haploid proliferation. Asexual cycles were common for maintenance of propagating haploid and diploid early unicellular eukaryotes. Reduction of accidental diploidy was referred to as “one-step meiosis” which meant gonomeric-based maternal and paternal genomic independent segregations. This interpretation was supported by exceptional chromosomal behaviors. However, multiple divisions expressing non-disjunction was the choice-explanation from evolutionists, which today is also suggested for the rarer LL-1 near haploid leukemia. These preserved non-mitotic mechanistic divisions systems are today witnessed in apomixes and parthenogenesis in many animal phyla. Thus, the indications are the modern genome of man harbors, relic-genetics from past “good” evolvements assuring “stable” proliferation of ancient, primitive eukaryotes, but with cancer-like effects for normal human cells.展开更多
Background:Sodium iodate(SI)is a chemical widely applied to induce retina degeneration in animal models.SI treatment caused formation of rosettes/folds in the outer nuclear layer(ONL)of the rat retina,but it was previ...Background:Sodium iodate(SI)is a chemical widely applied to induce retina degeneration in animal models.SI treatment caused formation of rosettes/folds in the outer nuclear layer(ONL)of the rat retina,but it was previously unclear whether SI also forms rosettes in mice.In addition,SI induced retina degeneration was never addressed in non-separate sclerochoroid/retina pigment epithelium/retina whole mount.Here we displayed features of retina degeneration including rosette formation in mice and developed a morphological analytic assessment using sclerochoroid/retina pigment epithelium/retina whole mounts.Methods:SI was intraperitoneally injected in Sprague-Dawley(SD)rats and C57BL/6J mice using a single dose(50 mg/kg)or with a dose range(10 to 50 mg/kg)in BALB/C mice.Rat retinas were investigated up to 2-week post-injection by histology and whole mounts,and mouse retinas were investigated up to 3-week post-injection by histology,fluorescent staining of sections and/or sclerochoroid/retina pigment epithelium/retina whole mounts for the morphological evaluations of the SI-induced retina damage.Results:SI-induced retina damage caused photoreceptor(PR)degeneration and rosettes/folds formation,as well as retina pigment epithelium degeneration and inward migration.It displayed mixed nuclei from choroid to PRs,due to layer disorganization,as shown by single horizontal images in the sclerochoroid/retina pigment epithelium/retina whole mounts.Measurement of the PR rosette area induced by SI provided a quantitative,morphological evaluation of retina degeneration.Conclusions:The method of non-separate sclerochoroid/retina pigment epithelium/retina whole staining and mount allows us to observe the integral horizontal view of damage from sclera to PR layers,which cannot be addressed by using sectioned and separate whole mount methods.This method is applicable for morphological evaluation of retina damage,especially in the subretinal layer.展开更多
Regenerative medicine has brought about refreshing new thinking about age old problems. However, some problems remain mostly untouched and are not being addressed. A point in question is the track of scar tissue left ...Regenerative medicine has brought about refreshing new thinking about age old problems. However, some problems remain mostly untouched and are not being addressed. A point in question is the track of scar tissue left behind post-operatively, which reveals the surgeon’s line of invasive incision. This confers on the patient an adverse psychological reminder and burden for the rest of his/her life. Most patients cannot afford corrective plastic surgery to ameliorate this skin defect. This paper seeks to ask whether biomedical scientists could play a role in arriving at a more pleasing cosmetic result, using a simple cell culture procedure of isolating un-manipulated autologous primary epidermal and dermal cells from a small skin tissue segment in close proximity to the surgeon’s incision line.展开更多
The hole-drilling method is one of the most wellknown methods for measuring residual stresses. To identify unknown plane stresses in a specimen, a circular hole is first drilled in the infinite plate under plane stres...The hole-drilling method is one of the most wellknown methods for measuring residual stresses. To identify unknown plane stresses in a specimen, a circular hole is first drilled in the infinite plate under plane stress, then the strains resulting from the hole drilling is measured. The strains may be acquired from interpreting the Moire signature around the hole. In crossed grating Moire interferometry, the horizontal and vertical displacement fields (u and v) can be obtained to determinate two strain fields and one shearing strain field. In this paper, by means of Moire interferometry and three directions grating (grating rosette) developed by the authors, three displacement fields (u, v and s) are obtained to acquire three strain fields. As a practical application, the hole-drilling method is adopted to measure the relief strains for aluminum and fiber reinforced composite. It is a step by step method; in each step a single laminate or equivalent depth is drilled to find some relationships between the drilling depth and the residual strains relieved in the fiber reinforced composite materials.展开更多
Three tests were used to assay the tumor-erythrocyte rosette forming rate for Sarcoma 180 (S180) bearing mice after abdominal injection or polyactin A.The results showed that the forming rates of the direct tumor-eryt...Three tests were used to assay the tumor-erythrocyte rosette forming rate for Sarcoma 180 (S180) bearing mice after abdominal injection or polyactin A.The results showed that the forming rates of the direct tumor-erythrocyte rosette,enhanced tumor-erythrocyte rosette, cooperative tumor-erythrocyte rosette in the tumor bearing mice group decreased by 22.07 %,25.87% and 24. 90% respectively,compared with those in the normal group. he difrerences were all remarkable(P<0. 01).After injection of polyactin A into the tumor bearing mice,the forming rates increased by 11. 64%, 16. 77% and 13.56% respectively.The dirference was also remarkable. These suggest that polyactin A can improve the adherence of erythrocytes and serum enhancing factors to tumor cells,and their cooperative adherence, thus strengthen the immune function of erythrocytes.展开更多
Plant secondary growth is of tremendous importance, not only for plant growth and development but also for economic usefulness. Secondary tissues such as xylem and phloem are the conducting tissues in plant vascular s...Plant secondary growth is of tremendous importance, not only for plant growth and development but also for economic usefulness. Secondary tissues such as xylem and phloem are the conducting tissues in plant vascular systems, essentially for water and nutrient transport, respectively. On the other hand, products of plant secondary growth are important raw materials and renewable sources of energy. Although advances have been recently made towards describing molecular mechanisms that regulate secondary growth, the genetic control for this process is not yet fully understood. Secondary cell wall formation in plants shares some common mechanisms with other plant secondary growth processes. Thus, studies on the secondary cell wall formation using Arabidopsis may help to understand the regulatory mechanisms for plant secondary growth. We previously reported phenotypic characterizations of an Arabidopsis semi-dominant mutant, upright rosette (uro), which is defective in secondary cell wall growth and has an unusually soft stem. Here, we show that lignification in the secondary cell wall in uro is aberrant by analyzing hypocotyl and stem. We also show genome-wide expression profiles of uro seedlings, using the Affymetrix GeneChip that contains approximately 24 000 Arabidopsis genes. Genes identified with altered expression levels include those that function in plant hormone biosynthesis and signaling, cell division and plant secondary tissue growth. These results provide useful information for further characterizations of the regulatory network in plant secondary cell wall formation.展开更多
I.INTRODUCTION The theory about 3 stages of embryonic hemopoiesis has been accepted by most investigators. Yolk sac is the first hemopoietic organ at the early stage of embryonic.
Wheat rosette stunt virus (WRSV) contains an RNA-dependent RNA polymerase. The RNA polymerase activity is associated with the viral nucleocapsid (NP).In vitro transcription of purified NP required all of the four ...Wheat rosette stunt virus (WRSV) contains an RNA-dependent RNA polymerase. The RNA polymerase activity is associated with the viral nucleocapsid (NP).In vitro transcription of purified NP required all of the four nucleoside triphosphates and Mg2+.There was a need of a proper salt concentration and some reducing reagents in the system for increasing the RNA polymerase activity.The optimum temperature for in vitro transcription was around 25℃.Within the first 90 min of in vitro reaction, incorporation rose linearly with the time course of incubation. The experiments of ribonuclease and deoxyribonuclease treatments showed that single-stranded RNAs were synthesized in vitro by the RNA polymerase.Two fractions of WRSV-NP could be separated by SDS-dissociation and ultracentrifugation.The supernatant fraction contained three structural proteins of NP: L, N and NS;and the pellet fraction contained the viral RNA.When the supernatant proteins and the viral RNA were mixed together, RNA polymerase activity展开更多
基金supported by the Universidad Nacional Mayor de San Marcos: Resolución Rectoral (RR) N° 00883-R-06, project code 061001191RR N° 00914-R-07, project code 071001281and RR N°03556-R-19, project code D19120061。
文摘A large fire of 233 ha in Huascarán National Park in Peru provided an opportunity to compare plant and bird responses in burned and nearby unburned zones of the puna. Heights and live diameters of flagship Puya raimondii rosettes(assigned to four broad developmental phases), plant communities(66 species in 24 families and nine growth forms) and bird communities(77 species in six trophic guilds) were monitored after the fire. Although no mortality was observed, Puya raimondii plants were affected by the fire, losing approximately 60% of their photosynthetic area across all developmental phases, but recovered quickly during the first two years after fire. The comparison of Puya rosette recovery after fire was complicated by the changes in live rosette diameter for unburned plants, which showed plasticity of photosynthetic area linked to seasonal and annual fluctuations in precipitation in this relatively dry environment(decreased by 26% for mature adult plants over the study period). Fire caused an immediate change in the density, biomass and composition of vegetation. Although the species present remained similar, their abundances changed significantly immediately after the fire, with notable reductions in dominant tussock grasses. This provided opportunities for other plants, resulting in higher postfire diversity of plant species, genera, families and growth forms. In turn, the changes in vegetation after fire affected the composition of birds according to their trophic guild. Granivores largely disappeared,generalists were mostly unaffected, and other guilds showed a more complex response. As the vegetation recovered, most displaced birds returned within approximately one year.
基金Supported by National Natural Science Foundation of China(Grant No.11972171)the Sixth Phase of Jiangsu Province“333 High Level Talent Training Project”Second Level Talents,Jiangsu Provincial Natural Science Foundation of China(Grant No.BK20180031)+2 种基金State Key Laboratory of Mechanics and Control of Mechanical Structures,Nanjing University of Aeronautics and Astronautics of China(Grant No.MCMS-E-0422G04)Open Fund of Key Laboratory for Intelligent Nano Materials and Devices of the Ministry of Education NJ2020003(Grant No.INMD-2021M05)111 Project(Grant No.B18027).
文摘The full-field multiaxial strain measurement is highly desired for application of structural monitoring but still challenging,especially when the manufacturing and assembling for largearea sensing devices is quite difficult.Compared with the traditional procedure of gluing commercial strain gauges on the structure surfaces for strain monitoring,the recently developed Direct-Ink-Writing(DIW)technology provides a feasible way to directly print sensors on the structure.However,there are still crucial issues in the design and printing strategies to be probed and improved.Therefore,in this work,we propose an integrated strategy from layered circuit scheme to rapid manufacturing of strain rosette sensor array based on the DIW technology.Benefit from the innovative design with simplified circuit layout and the advantages of DIW for printing multilayer structures,here we achieve optimization design principle for strain rosette sensor array with scalable circuit layout,which enable a hierarchical printing strategy for multiaxial strain monitoring in large scale or multiple domains.The strategy is highly expected to adapt for the emerging requirement in various applications such as integrated soft electronics,nondestructive testing and small-batch medical devices.
文摘The present comparative review discusses conservation of early evolutionary, relic genetics in the genome of man, which determine two different mechanistic reductive division systems expressed by normal, human diploid cells. The divisions were orderly and segregated genomes reductively to near-diploid daughter cells, which showed gain of a proliferative advantage (GPA) over cells of origin. This fact of GPA expression is a fundamental requirement for initiation of tumorigenesis. The division systems were responses to a carcinogen-free induction system, consisting of short (1 - 3 days) exposures of young cells to nutritional deprivation of amino acid glutamine (AAD). In recovery growth (2 - 4 days) endo-tetra/ochtoploid cells and normal diploid metaphase cells demonstrated chromosomal reductive divisions to respectively heterozygous and homozygous altered daughter cells. Both division systems showed co-segregating whole complements, which for reduction of the diploid metaphases could only arise from gonomeric-based autonomous behavior of maternal and paternal (mat/pat) genomes. The timely associated appearance with these latter divisions was fast growing small-cells (1/2 volume-size reduced from normal diploidy), which became homozygous from haploid, genomic doubling. Both reductive divisions thus produced genome altered progeny cells with GPA, which was associated with pre-cancer-like cell-phenotypic changes. Since both “undesirable” reductive divisions expressed orderly division sequences, their genetic controls were assumed to be “old genetics”, evolutionarily conserved in the genome of man. Support for this idea was a search for evidential material in the evolutionary record from primeval time, when haploid organisms were established. The theory was that endopolyploid and gonomery-based reductive divisions relieved the early eukaryotic organisms from accidental, non-proliferative diploidy and polyploidy, bringing the organism back to vegetative haploid proliferation. Asexual cycles were common for maintenance of propagating haploid and diploid early unicellular eukaryotes. Reduction of accidental diploidy was referred to as “one-step meiosis” which meant gonomeric-based maternal and paternal genomic independent segregations. This interpretation was supported by exceptional chromosomal behaviors. However, multiple divisions expressing non-disjunction was the choice-explanation from evolutionists, which today is also suggested for the rarer LL-1 near haploid leukemia. These preserved non-mitotic mechanistic divisions systems are today witnessed in apomixes and parthenogenesis in many animal phyla. Thus, the indications are the modern genome of man harbors, relic-genetics from past “good” evolvements assuring “stable” proliferation of ancient, primitive eukaryotes, but with cancer-like effects for normal human cells.
基金supported by the National Institutes of Health(R01EY027827,QX)and VCU(VETAR 2021,YO)grants.
文摘Background:Sodium iodate(SI)is a chemical widely applied to induce retina degeneration in animal models.SI treatment caused formation of rosettes/folds in the outer nuclear layer(ONL)of the rat retina,but it was previously unclear whether SI also forms rosettes in mice.In addition,SI induced retina degeneration was never addressed in non-separate sclerochoroid/retina pigment epithelium/retina whole mount.Here we displayed features of retina degeneration including rosette formation in mice and developed a morphological analytic assessment using sclerochoroid/retina pigment epithelium/retina whole mounts.Methods:SI was intraperitoneally injected in Sprague-Dawley(SD)rats and C57BL/6J mice using a single dose(50 mg/kg)or with a dose range(10 to 50 mg/kg)in BALB/C mice.Rat retinas were investigated up to 2-week post-injection by histology and whole mounts,and mouse retinas were investigated up to 3-week post-injection by histology,fluorescent staining of sections and/or sclerochoroid/retina pigment epithelium/retina whole mounts for the morphological evaluations of the SI-induced retina damage.Results:SI-induced retina damage caused photoreceptor(PR)degeneration and rosettes/folds formation,as well as retina pigment epithelium degeneration and inward migration.It displayed mixed nuclei from choroid to PRs,due to layer disorganization,as shown by single horizontal images in the sclerochoroid/retina pigment epithelium/retina whole mounts.Measurement of the PR rosette area induced by SI provided a quantitative,morphological evaluation of retina degeneration.Conclusions:The method of non-separate sclerochoroid/retina pigment epithelium/retina whole staining and mount allows us to observe the integral horizontal view of damage from sclera to PR layers,which cannot be addressed by using sectioned and separate whole mount methods.This method is applicable for morphological evaluation of retina damage,especially in the subretinal layer.
文摘Regenerative medicine has brought about refreshing new thinking about age old problems. However, some problems remain mostly untouched and are not being addressed. A point in question is the track of scar tissue left behind post-operatively, which reveals the surgeon’s line of invasive incision. This confers on the patient an adverse psychological reminder and burden for the rest of his/her life. Most patients cannot afford corrective plastic surgery to ameliorate this skin defect. This paper seeks to ask whether biomedical scientists could play a role in arriving at a more pleasing cosmetic result, using a simple cell culture procedure of isolating un-manipulated autologous primary epidermal and dermal cells from a small skin tissue segment in close proximity to the surgeon’s incision line.
基金the National Natural Science Foundation of China (10772117, 10572089)
文摘The hole-drilling method is one of the most wellknown methods for measuring residual stresses. To identify unknown plane stresses in a specimen, a circular hole is first drilled in the infinite plate under plane stress, then the strains resulting from the hole drilling is measured. The strains may be acquired from interpreting the Moire signature around the hole. In crossed grating Moire interferometry, the horizontal and vertical displacement fields (u and v) can be obtained to determinate two strain fields and one shearing strain field. In this paper, by means of Moire interferometry and three directions grating (grating rosette) developed by the authors, three displacement fields (u, v and s) are obtained to acquire three strain fields. As a practical application, the hole-drilling method is adopted to measure the relief strains for aluminum and fiber reinforced composite. It is a step by step method; in each step a single laminate or equivalent depth is drilled to find some relationships between the drilling depth and the residual strains relieved in the fiber reinforced composite materials.
文摘Three tests were used to assay the tumor-erythrocyte rosette forming rate for Sarcoma 180 (S180) bearing mice after abdominal injection or polyactin A.The results showed that the forming rates of the direct tumor-erythrocyte rosette,enhanced tumor-erythrocyte rosette, cooperative tumor-erythrocyte rosette in the tumor bearing mice group decreased by 22.07 %,25.87% and 24. 90% respectively,compared with those in the normal group. he difrerences were all remarkable(P<0. 01).After injection of polyactin A into the tumor bearing mice,the forming rates increased by 11. 64%, 16. 77% and 13.56% respectively.The dirference was also remarkable. These suggest that polyactin A can improve the adherence of erythrocytes and serum enhancing factors to tumor cells,and their cooperative adherence, thus strengthen the immune function of erythrocytes.
基金Supported by the Hi-Tech Research and Development(863)Program of China(20060110Z1012) to H.Hthe National Natural Science Foundation of China(30570159) to Y.S
文摘Plant secondary growth is of tremendous importance, not only for plant growth and development but also for economic usefulness. Secondary tissues such as xylem and phloem are the conducting tissues in plant vascular systems, essentially for water and nutrient transport, respectively. On the other hand, products of plant secondary growth are important raw materials and renewable sources of energy. Although advances have been recently made towards describing molecular mechanisms that regulate secondary growth, the genetic control for this process is not yet fully understood. Secondary cell wall formation in plants shares some common mechanisms with other plant secondary growth processes. Thus, studies on the secondary cell wall formation using Arabidopsis may help to understand the regulatory mechanisms for plant secondary growth. We previously reported phenotypic characterizations of an Arabidopsis semi-dominant mutant, upright rosette (uro), which is defective in secondary cell wall growth and has an unusually soft stem. Here, we show that lignification in the secondary cell wall in uro is aberrant by analyzing hypocotyl and stem. We also show genome-wide expression profiles of uro seedlings, using the Affymetrix GeneChip that contains approximately 24 000 Arabidopsis genes. Genes identified with altered expression levels include those that function in plant hormone biosynthesis and signaling, cell division and plant secondary tissue growth. These results provide useful information for further characterizations of the regulatory network in plant secondary cell wall formation.
文摘I.INTRODUCTION The theory about 3 stages of embryonic hemopoiesis has been accepted by most investigators. Yolk sac is the first hemopoietic organ at the early stage of embryonic.
基金Project supported by the National Natural Science Foundation of China.
文摘Wheat rosette stunt virus (WRSV) contains an RNA-dependent RNA polymerase. The RNA polymerase activity is associated with the viral nucleocapsid (NP).In vitro transcription of purified NP required all of the four nucleoside triphosphates and Mg2+.There was a need of a proper salt concentration and some reducing reagents in the system for increasing the RNA polymerase activity.The optimum temperature for in vitro transcription was around 25℃.Within the first 90 min of in vitro reaction, incorporation rose linearly with the time course of incubation. The experiments of ribonuclease and deoxyribonuclease treatments showed that single-stranded RNAs were synthesized in vitro by the RNA polymerase.Two fractions of WRSV-NP could be separated by SDS-dissociation and ultracentrifugation.The supernatant fraction contained three structural proteins of NP: L, N and NS;and the pellet fraction contained the viral RNA.When the supernatant proteins and the viral RNA were mixed together, RNA polymerase activity