By both the Charpy V-notched impact and the projectile tests, we here investigated the dynamic fracture behavior of a recently developed ultrastrong lightweight steel comprising a hierarchical martensitic matrix, disp...By both the Charpy V-notched impact and the projectile tests, we here investigated the dynamic fracture behavior of a recently developed ultrastrong lightweight steel comprising a hierarchical martensitic matrix, dispersed ultra-fine-retained austenite grains and oriented δ-ferrite lamellas, the latter being due to high Al and Si contents employed for low-density design. This steel shows a superior combination of specific ultimate tensile strength and impact toughness to other ultrastrong steels and has successfully arrested a real steel-cored bullet shot. These are attributed to the densely textured δ-ferrite lamellas that can deflect the propagating cracks until they are trapped and enclosed besides austenite-to-martensite transformation crack closure, leading to more energy consumed before failure. These results suggest a new pathway for toughening ultrastrong lightweight steels.展开更多
In recent years, the harmful effects of blue light (400 - 500 nm) as a component of visible light (400 - 700 nm) have increasingly gained attention of science, industry, and consumers. To date, only a few in vivo test...In recent years, the harmful effects of blue light (400 - 500 nm) as a component of visible light (400 - 700 nm) have increasingly gained attention of science, industry, and consumers. To date, only a few in vivo test methods for measuring the effects of blue light on the skin have been described. A direct measurement method that can detect the immediate effects of blue light on the epidermal permeability barrier (EPB) is still lacking. In this study, we present a new methodological approach that can be used to investigate both the protective and regenerative effects of cosmetic products on the EPB after blue light irradiation. In a study with 14 female volunteers, it was investigated whether the regular application of an O/W emulsion (day cream) can strengthen and protect the epidermal barrier against damaging blue light radiation of 60 J/cm2 (protective study design) and also whether a disruption of the epidermal barrier caused by blue light radiation is restored faster and better by the regular application of another O/W emulsion (night cream) than in product-untreated skin (regenerative study design). The two O/W emulsions are different in plant oil, active ingredient composition and texture. The seven-day treatment with the day cream initially led to a significant increase in the normalized lipid lamellae length in the intercellular space, whereas the irradiation with blue light after 24 hours led to a significant decrease in the lipid lamellae length in the untreated test area, but not in the area previously treated with the product. Regarding the regenerative study design, a two-day treatment with the night cream was able to restore a blue-light-induced decrease in lipid lamellae length in the intercellular space. In summary, with the study designs presented here, the protective and regenerative effect of two cosmetic products could be demonstrated for the first time on the integrity of the EPB after blue light irradiation and the data showed that the Lipbarvis® method is suitable for investigating the damaging effects of blue light on the EPB in vivo.展开更多
Exsolution microstructures in olivine grains from dunite units in a few selected tectonic environments are reported here. They include lamellae of clinopyroxene and clinopyroxene-magnetite intergrowth in the Gaositai ...Exsolution microstructures in olivine grains from dunite units in a few selected tectonic environments are reported here. They include lamellae of clinopyroxene and clinopyroxene-magnetite intergrowth in the Gaositai and Yellow Hill Alaskan-type complexes, clinopyroxene-magnetite intergrowth in the Klzildag ophiolite, and chromite lamellae in the Hongshishan mafic-ultramafic intrusive complex. These lamellae commonly occur as needle- or rod-like features and are oriented in olivine grains. The host olivine grains have Fo contents of 92.5-92.6 in the Gaositai complex, 86.5-90.1 in the Yellow Hill complex, 93.2-93.4 in the Klzlldag ophiolite and 86.9-88.3 in the Hongshishan complex. Clinopyroxene in the rod-like intergrowth exsolved in olivine grains in the Gaositai and Yellow Hill is diopside with similar major element compositions of CaO (23.6-24.3wt%), SiO2 (52.2-54.0wt%), A1203 (0.67-2.15wt%), Cr203 (0.10-0.42wt%) and Na20 (0.14-0.26wt%). It falls into the compositional field of hydrothermal clinopyroxene and its origin is thus probably related to reaction between dunite and fluids. The enrichment of the fluids in Ca2+, Fe3+, Cr3+ and Na+, resulted in elevated concentrations of these cations in olivine solid solutions via the reaction. With decreasing temperature, the olivine solid solutions altered to an intergrowth of magnetite and clinopyroxene. The Fe3+ and Cr3+ preferentially partitioned into magnetite, while Ca2+ and Na+ entered clinopyroxene. Since the studied Alaskan-type complexes and ophiolite formed in a subduction environment, the fluids were probably released from the subducted slab. In contrast, the exsolved chromite in olivine grains from the Hongshishan complex that formed in post-orogenic extension setting can be related to olivine equilibrated with Cr-bearing liquid. Similarly, these lamellae have all been observed in serpentine surrounding olivine grains, indicating genetic relations with serpentinization.展开更多
In No. 50 kimberlite pipe of Fuxian County, Liaoning Province, an eclogite inclusion(nodule), which is extremely rare in kimberlites, was discovered and phlogopite exsolutionlamellae were found in garnets of the inclu...In No. 50 kimberlite pipe of Fuxian County, Liaoning Province, an eclogite inclusion(nodule), which is extremely rare in kimberlites, was discovered and phlogopite exsolutionlamellae were found in garnets of the inclusion. Microscopic, TEM and energy spectral observa-tions and studies confirmed that these lamellae are phlogopite. They are colourless and acicularin section, generally 0.5-5μm in width and 10-100μm in length. Nevertheless, fine lamellae,0.05-0.1μm wide and 1-2μm long, are also well developed. Along [111] of the garnet, three setsof phlogopite lamellae show oriented arrangement approximately at angles of 60°-70°, indi-cating that these lamellae might be the product of exsolution from garnet as a result ofpressure-release when eclogite ascended from the relatively deep level to the relatively shallowlevel of the mantle. Tiny acicular exsolution minerals (or inclusions) are commonly found ingarnet and pyroxene in eclogite inclusions of kimberlites all over the world and it has been re-ported that the identified exsolution minerals include pyroxene and rutile. This is the first timethat phlogopite exsolution lamillae were found in eclogite inclusions in the world.展开更多
In the wake of ever-increasing environmental pollution, human skin in the modern urban world is exposed to increased levels of harmful environmental pollutants. Many studies have shown that these pollutants can weaken...In the wake of ever-increasing environmental pollution, human skin in the modern urban world is exposed to increased levels of harmful environmental pollutants. Many studies have shown that these pollutants can weaken the epidermal skin barrier and thus facilitate the penetration of these substances into the skin. An important goal of modern skin care against harmful environmental influences should therefore be to protect and strengthen the epidermal barrier and to repair occurring damage quickly and efficiently. With this in mind, in the present study we investigated what damage cigarette smoke causes to the epidermal barrier and 1) whether the regular application of a O/W emulsion (Day Cream) can protectively strengthen the epidermal barrier against environmental damage and 2) whether a cigarette smoke-induced disruption of the epidermal barrier is restored faster and better by the regular application of a another O/W emulsion (Night Cream) than in product-untreated skin. The two products are slightly different in plant-oil, active ingredient composition and texture. Firstly, the study has shown that the Lipbarvis<sup>?</sup> method is suitable for measuring the effect of cigarette smoke, in contrast to conventional biophysical measurement methods (transepidermal water loss, skin hydration). Secondly, both products were able to improve skin barrier function in the corresponding test scenario. This was demonstrated for both test products by a significantly reduced TEWL, significantly increased skin hydration and significantly improved length of the lipid lamellae in the intercellular space, as well as the protective effect of the day cream on the epidermal skin barrier and the regenerative properties of the tested night cream. .展开更多
A two-phase TiAl-based alloy with fully lamellar structure has been deformed al room temperature and the deformed microstructures have been examined in dtails by optical microscopy(OM), scanning electron microscopy(...A two-phase TiAl-based alloy with fully lamellar structure has been deformed al room temperature and the deformed microstructures have been examined in dtails by optical microscopy(OM), scanning electron microscopy(SEM) and transmission electron microscopy(TEM) . Deformation mechanisms in the γ-TiAl phase has been defined and the role of grain boundaries in the deformation and fracture has been assessed Some of the mechanisms of interactions between twinning or gliding dislocations and three types of γ γ domain boundaries or γ α_2 interface in a lamellar grain have been identified and resistance of the various domain boundaries or the interface to the propagation of twinning has been evaluated展开更多
The fracture mechanism of lamellar Ti 49%Al alloy was investigated through studying the interactions between crack and lamellae or grain boundary. The results indicated that the nucleation and propagation mechanisms o...The fracture mechanism of lamellar Ti 49%Al alloy was investigated through studying the interactions between crack and lamellae or grain boundary. The results indicated that the nucleation and propagation mechanisms of crack depends on not only the lamellar orientations within grain but also the types of grain boundaries. When the angle between tensile axis and lamellae is relatively large, the main crack parallel to the lamellae propagates by nucleation, growth and linkage with interfacial microcracks. When the tensile axis is nearly parallel to the lamellae, the main crack perpendicular to the lamellae propagates by nucleation, growth and linkage with two types of microcracks, e.g. translamellar microcrack and interface delamination. In addition, the interlock grain boundary nearly parallel to the tensile axis is benefit to fracture toughness, the grain boundary nearly perpendicular to the tensile axis is bad for the toughness. [展开更多
This work deals with determining the optimum thickness of the lamella wafer of silicon solar cell. The (p) base region makes up the bulk of the thickness of the wafer. This thickness has always been a factor limiting ...This work deals with determining the optimum thickness of the lamella wafer of silicon solar cell. The (p) base region makes up the bulk of the thickness of the wafer. This thickness has always been a factor limiting the performance of the solar cell, as it produces the maximum amount of electrical charges, contributing to the photocurrent. Determining the thickness of the wafer cannot be only mechanical. It takes into account the internal physical mechanisms of generation-diffusion-recombination of excess minority carriers. They are also influenced by external factors such as temperature and magnetic field. Under these conditions, magneto transport equation is required to be applied on excess minority carrier in lamella base silicon solar cell. It yields maximum diffusion coefficient which result on Lorentz law and Umklapp process. Then from photocurrent, back surface recombination velocity expressions are derived, both maximum diffusion coefficient and thickness dependent. The plot of the back surface recombination calibration curves as function of lamella width, leads to its maximum values, trough intercept points. Lamella optimum width is then obtained, both temperature and magnetic field dependent and expressed in relationships to show the required base thickness in the elaboration process.展开更多
Exploration of novel genetic resources against root-knot nematode(RKN)is necessary to strengthen the resistance breeding program in cultivated rice,and investigations on the role of genotype-specific root anatomy in c...Exploration of novel genetic resources against root-knot nematode(RKN)is necessary to strengthen the resistance breeding program in cultivated rice,and investigations on the role of genotype-specific root anatomy in conferring a structural barrier against nematode invasion are largely underexplored.Here,we reported a highly-resistant rice germplasm Phule Radha that conferred remarkably lower RKN parasitic fitness in terms of reduced penetration and delayed development and reproduction when compared with susceptible cultivar PB1121.Using histological and biochemical analyses,we demonstrated that an enhanced suberin deposition in the exodermal root tip tissue of Phule Radha compared to PB1121 can effectively form a penetrative barrier against RKN infection,and this preformed barrier in the control tissue did not necessarily alter to a greater extent when challenged with RKN stress.Using qRT-PCR analysis,we showed that a number of suberin biosynthesis genes were greatly expressed in the exodermis of Phule Radha compared to PB1121.In sum,the present study established the role of rice exodermal barrier system in defense against an important soil-borne pathogen.展开更多
AIM:To report the clinical outcomes of utilizing a three-layer flap and graft in reconstruction of the lower lid in one session.METHODS:Seventeen patients with total or near total lower eyelid defect were included.The...AIM:To report the clinical outcomes of utilizing a three-layer flap and graft in reconstruction of the lower lid in one session.METHODS:Seventeen patients with total or near total lower eyelid defect were included.The defects were reconstructed in three layers.Posterior lamella was reconstructed by using tarsoconjunctival free graft from the ipsilateral upper lid and periosteal flap from lateral orbital rim.Mobilization of residual orbicularis muscle provided a rich blood supply;and the anterior lamella was reconstructed by skin flap prepared from upper lid blepharoplasty as a one-pedicular or bipedicular bucket handle flap.RESULTS:The cause of lower eyelid defect was basal cell carcinoma in 15 patients and trauma in two of them.No intraoperative and postoperative complication occurred.Patients were followed from 10 to 15mo postoperatively.Cosmetic results were favorable in all patients and we had acceptable functional results.Thickness of the reconstructed tissue was a concern in early postoperative period.CONCLUSION:Three-layer lower lid reconstruction in one session is an effective technique for total lower lid reconstruction with minimal complications and acceptable functional and aesthetic outcomes and can be considered as a safe alternative for the preexisting techniques.展开更多
The silicon solar cell with series-connected vertical junction is studied with different lamella widths—the expression of the ac recombination velocity of the excess minority carrier at the back surface is establishe...The silicon solar cell with series-connected vertical junction is studied with different lamella widths—the expression of the ac recombination velocity of the excess minority carrier at the back surface is established. Spectroscopy technique reveals dominated impact of the lamella widths of the base.展开更多
Reconstructive surgery of the eyelid after tumor excision,trauma or other causes can be challenging,especially due to the complexities of the anatomic structures and to the necessity of both functional and aesthetic s...Reconstructive surgery of the eyelid after tumor excision,trauma or other causes can be challenging,especially due to the complexities of the anatomic structures and to the necessity of both functional and aesthetic successful outcomes.The aim of this minireview was to investigate the use of tissue transplantation in eyelid reconstruction.Surgical procedures are various,based on the use of both flaps,pedicled or free,and grafts,in order to guarantee adequate tissue reconstruction and blood supply,which are necessary for correct healing.Common techniques normally include the use of local tissues,combining non-vascularized grafts with a vascularized flap for the two lamellae repair,to attempt a reconstruction similar to the original anatomy.When defects are too wide,vast,deep,and complex or when no adjacent healthy tissues are available,distant area tissues need to be recruited as free flaps or grafts and paired with mucosal layer reconstruction.With regards to the anterior lamella,full thickness skin grafts are commonly preferred.With regards to the reconstruction of posterior lamella,there are different graft options,which include conjunctival or tarsoconjunctival,mucosal or palatal or cartilaginous grafts usually combined with local flaps.Free flap transplantation,normally reserved for rare select cases,include the use of the radial forearm and anterolateral flaps combined with mucosal grafts,which are surgical options currently reported in the literature.展开更多
Using general multi-phase-field model,detailed microstructures corresponding to different initial lamellar sets were simulated in a binary eutectic alloy with an asymmetric phase diagram.The simulation results show th...Using general multi-phase-field model,detailed microstructures corresponding to different initial lamellar sets were simulated in a binary eutectic alloy with an asymmetric phase diagram.The simulation results show that regular or unstable oscillating lamellar structures depend on the initial lamellar widths of two solid phases.A lamellar morphology map associating with the initial widths has been derived,which is capable of showing the condition of forming various lamella structures.For instance,a regular lamella was formed with fast solidification while large lamella resulted from disorder growth with low interfacial velocity. The investigated interface velocities indicate that with fast solidification to form regular lamella,a disorder growth manner or a large lamellar spacing causes a low interface velocity.These results are in good agreement with those proposed by Jackson-Hunt model.展开更多
The rod-like assembly from BAB block copolymer with hydrophilic middle block A in aqueous solution was described. The copolymer used is polystyrene (PS)39-b-poly(4-vinylpyridine)(P4VP)98-b-PS39 (the subscripts are the...The rod-like assembly from BAB block copolymer with hydrophilic middle block A in aqueous solution was described. The copolymer used is polystyrene (PS)39-b-poly(4-vinylpyridine)(P4VP)98-b-PS39 (the subscripts are the average polymerization degree of corresponding blocks) triblock copolymer with Mw/Mn = 1.15. The aggregates were characterized by transmission electron microscopy and atomic force microscopy. The dependence of rod-like aggregate formation on solvents, pH, and polymer concentrations was investigated. The rod-like aggregates were formed when using dioxane as initial solvent, while spherical micelles were formed using DMF. Elevating pH values from 4 to 5 to 7 and decreasing initial copolymer concentrations from 1.5 wt% to 1.0 wt% to 0.5 wt% were favorable for the formation of well-defined rod-like aggregates. In addition, the bicontinuous rods and lamellae were observed when preparing colloid solutions in appropriate conditions.展开更多
Microphase separation and lamellar structure of segmented polyether- and polyester-polyurethanes have been investigated by means of transmission electron microscopy with the ruthenium tetroxide staining technique. The...Microphase separation and lamellar structure of segmented polyether- and polyester-polyurethanes have been investigated by means of transmission electron microscopy with the ruthenium tetroxide staining technique. The results show that the RuO_4 staining technique is simpler and may give better image contrast than other staining methods for this polymer. Microphase separation and lamellar structure of segmented polyether-and polyester-polyurethanes were directly observed and discussed.展开更多
The crystalline behavior of urethane substitute polydiacetylene was studied by using pohrized light and electron microscopy. The lamellar morphological structure was observed in the crystallized films. The thickness o...The crystalline behavior of urethane substitute polydiacetylene was studied by using pohrized light and electron microscopy. The lamellar morphological structure was observed in the crystallized films. The thickness of lamellae is about 300A, being independent of the crystalline temperature. But the size and density of lamellae were dependent on the crystallization temperature. If the molten film was sheared during the crystallzation process the oriented lamellae grew with their long axes perpendicular to the direction of shear and the chain direction was normal to the lamellar surface.展开更多
A novel Fe-enriched lamella sandwich phase (χ-phase) has been found to precipitate along the basal (0001)_(Mg) planes in the heat-treated Mg-Gd-Fe alloy and its structure is clearly revealed by means of atomic-resolu...A novel Fe-enriched lamella sandwich phase (χ-phase) has been found to precipitate along the basal (0001)_(Mg) planes in the heat-treated Mg-Gd-Fe alloy and its structure is clearly revealed by means of atomic-resolution transmission electron microscopy.The layered χ-phase only has a thickness of mono-unit-cell and consists invariably of ten atomic layers stacking along the[0001]_(Mg) direction,of which the outermost atomic layers had larger in-plane atom-pillar spacing than the inner layers.Fe/Gd atoms are mainly enriched in the outer four atomic layers in the χ-phase,forming two structurally unsymmetrical four-layer shells to sandwich the middle two Mg layers.An atomic model has been proposed for this layered sandwich-structured χ-phase.展开更多
Wild-type potato (Solanum tuberosum L.) plants and their transformants harboring agrobacterial rolB or rolC genes under control of the patatin class I promoter were cultured in vitro. These plants were used as a sourc...Wild-type potato (Solanum tuberosum L.) plants and their transformants harboring agrobacterial rolB or rolC genes under control of the patatin class I promoter were cultured in vitro. These plants were used as a source of single-node stem cuttings. The structure of native starch in tubers formed on cuttings was determined using methods of X-ray scattering and differential scanning microcalorimetry (DSC). It was found that in starch from tubers of rolB plants the melting temperature of crystalline lamella was lower and their thickness was less than that in wild-type potato. In tubers of rolC plants starch differed from starch in wild-type plants by a higher melting temperature, reduced melting enthalpy, and a greater thickness of crystalline lamellae. The melting of starch from tubers of rolC plants proceeded as the melting of two independent crystalline structures with melting temperatures of 338.0°K and 342.8°K. Overall data show that starches of different structure can be obtained by using transgenic approach.展开更多
We studied morphofunctional properties of human platelets, treated with low doses of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>). It was shown that platelet incubation with 20 - 75 <em>...We studied morphofunctional properties of human platelets, treated with low doses of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>). It was shown that platelet incubation with 20 - 75 <em>μ</em>M H<sub>2</sub>O<sub>2</sub> during 24 hours at 20<span style="white-space:nowrap;">°</span>C - 22<span style="white-space:nowrap;">°</span>C did not cause visible structural deficiencies in cells. Platelets maintained their adhesion activity and velocity of degranulation at 20 <em>μ</em>M H<sub>2</sub>O<sub>2</sub>. 30 - 60 μM H<sub>2</sub>O<sub>2</sub> dose-dependently reduced lamella’s growth and allowed retaining granule bulk inside cytoplasm of spreading platelets. After 1 - 2 hours, the most effect of platelet granules’ stabilization was registered at samples, previously incubated with 60 μM H<sub>2</sub>O<sub>2</sub>. Adrenalin activation led to rapid degranulation of stabilized platelets, whereas lamella’s growth in activated platelets was low or medium.展开更多
基金financial support from National Natural Science Foundation of China(Grant Nos.51831002,51904028 and 52233018),ChinaFundamental Research Funds for the Central Universities(Grant No.06500151),China.
文摘By both the Charpy V-notched impact and the projectile tests, we here investigated the dynamic fracture behavior of a recently developed ultrastrong lightweight steel comprising a hierarchical martensitic matrix, dispersed ultra-fine-retained austenite grains and oriented δ-ferrite lamellas, the latter being due to high Al and Si contents employed for low-density design. This steel shows a superior combination of specific ultimate tensile strength and impact toughness to other ultrastrong steels and has successfully arrested a real steel-cored bullet shot. These are attributed to the densely textured δ-ferrite lamellas that can deflect the propagating cracks until they are trapped and enclosed besides austenite-to-martensite transformation crack closure, leading to more energy consumed before failure. These results suggest a new pathway for toughening ultrastrong lightweight steels.
文摘In recent years, the harmful effects of blue light (400 - 500 nm) as a component of visible light (400 - 700 nm) have increasingly gained attention of science, industry, and consumers. To date, only a few in vivo test methods for measuring the effects of blue light on the skin have been described. A direct measurement method that can detect the immediate effects of blue light on the epidermal permeability barrier (EPB) is still lacking. In this study, we present a new methodological approach that can be used to investigate both the protective and regenerative effects of cosmetic products on the EPB after blue light irradiation. In a study with 14 female volunteers, it was investigated whether the regular application of an O/W emulsion (day cream) can strengthen and protect the epidermal barrier against damaging blue light radiation of 60 J/cm2 (protective study design) and also whether a disruption of the epidermal barrier caused by blue light radiation is restored faster and better by the regular application of another O/W emulsion (night cream) than in product-untreated skin (regenerative study design). The two O/W emulsions are different in plant oil, active ingredient composition and texture. The seven-day treatment with the day cream initially led to a significant increase in the normalized lipid lamellae length in the intercellular space, whereas the irradiation with blue light after 24 hours led to a significant decrease in the lipid lamellae length in the untreated test area, but not in the area previously treated with the product. Regarding the regenerative study design, a two-day treatment with the night cream was able to restore a blue-light-induced decrease in lipid lamellae length in the intercellular space. In summary, with the study designs presented here, the protective and regenerative effect of two cosmetic products could be demonstrated for the first time on the integrity of the EPB after blue light irradiation and the data showed that the Lipbarvis® method is suitable for investigating the damaging effects of blue light on the EPB in vivo.
基金financially supported by the National Natural Science Foundation of China (Grants 41522203, 41673037 and 41772055)Youth Innovation Promotion Association, Chinese Academy of Sciences (Grant 2017095)
文摘Exsolution microstructures in olivine grains from dunite units in a few selected tectonic environments are reported here. They include lamellae of clinopyroxene and clinopyroxene-magnetite intergrowth in the Gaositai and Yellow Hill Alaskan-type complexes, clinopyroxene-magnetite intergrowth in the Klzildag ophiolite, and chromite lamellae in the Hongshishan mafic-ultramafic intrusive complex. These lamellae commonly occur as needle- or rod-like features and are oriented in olivine grains. The host olivine grains have Fo contents of 92.5-92.6 in the Gaositai complex, 86.5-90.1 in the Yellow Hill complex, 93.2-93.4 in the Klzlldag ophiolite and 86.9-88.3 in the Hongshishan complex. Clinopyroxene in the rod-like intergrowth exsolved in olivine grains in the Gaositai and Yellow Hill is diopside with similar major element compositions of CaO (23.6-24.3wt%), SiO2 (52.2-54.0wt%), A1203 (0.67-2.15wt%), Cr203 (0.10-0.42wt%) and Na20 (0.14-0.26wt%). It falls into the compositional field of hydrothermal clinopyroxene and its origin is thus probably related to reaction between dunite and fluids. The enrichment of the fluids in Ca2+, Fe3+, Cr3+ and Na+, resulted in elevated concentrations of these cations in olivine solid solutions via the reaction. With decreasing temperature, the olivine solid solutions altered to an intergrowth of magnetite and clinopyroxene. The Fe3+ and Cr3+ preferentially partitioned into magnetite, while Ca2+ and Na+ entered clinopyroxene. Since the studied Alaskan-type complexes and ophiolite formed in a subduction environment, the fluids were probably released from the subducted slab. In contrast, the exsolved chromite in olivine grains from the Hongshishan complex that formed in post-orogenic extension setting can be related to olivine equilibrated with Cr-bearing liquid. Similarly, these lamellae have all been observed in serpentine surrounding olivine grains, indicating genetic relations with serpentinization.
文摘In No. 50 kimberlite pipe of Fuxian County, Liaoning Province, an eclogite inclusion(nodule), which is extremely rare in kimberlites, was discovered and phlogopite exsolutionlamellae were found in garnets of the inclusion. Microscopic, TEM and energy spectral observa-tions and studies confirmed that these lamellae are phlogopite. They are colourless and acicularin section, generally 0.5-5μm in width and 10-100μm in length. Nevertheless, fine lamellae,0.05-0.1μm wide and 1-2μm long, are also well developed. Along [111] of the garnet, three setsof phlogopite lamellae show oriented arrangement approximately at angles of 60°-70°, indi-cating that these lamellae might be the product of exsolution from garnet as a result ofpressure-release when eclogite ascended from the relatively deep level to the relatively shallowlevel of the mantle. Tiny acicular exsolution minerals (or inclusions) are commonly found ingarnet and pyroxene in eclogite inclusions of kimberlites all over the world and it has been re-ported that the identified exsolution minerals include pyroxene and rutile. This is the first timethat phlogopite exsolution lamillae were found in eclogite inclusions in the world.
文摘In the wake of ever-increasing environmental pollution, human skin in the modern urban world is exposed to increased levels of harmful environmental pollutants. Many studies have shown that these pollutants can weaken the epidermal skin barrier and thus facilitate the penetration of these substances into the skin. An important goal of modern skin care against harmful environmental influences should therefore be to protect and strengthen the epidermal barrier and to repair occurring damage quickly and efficiently. With this in mind, in the present study we investigated what damage cigarette smoke causes to the epidermal barrier and 1) whether the regular application of a O/W emulsion (Day Cream) can protectively strengthen the epidermal barrier against environmental damage and 2) whether a cigarette smoke-induced disruption of the epidermal barrier is restored faster and better by the regular application of a another O/W emulsion (Night Cream) than in product-untreated skin. The two products are slightly different in plant-oil, active ingredient composition and texture. Firstly, the study has shown that the Lipbarvis<sup>?</sup> method is suitable for measuring the effect of cigarette smoke, in contrast to conventional biophysical measurement methods (transepidermal water loss, skin hydration). Secondly, both products were able to improve skin barrier function in the corresponding test scenario. This was demonstrated for both test products by a significantly reduced TEWL, significantly increased skin hydration and significantly improved length of the lipid lamellae in the intercellular space, as well as the protective effect of the day cream on the epidermal skin barrier and the regenerative properties of the tested night cream. .
文摘A two-phase TiAl-based alloy with fully lamellar structure has been deformed al room temperature and the deformed microstructures have been examined in dtails by optical microscopy(OM), scanning electron microscopy(SEM) and transmission electron microscopy(TEM) . Deformation mechanisms in the γ-TiAl phase has been defined and the role of grain boundaries in the deformation and fracture has been assessed Some of the mechanisms of interactions between twinning or gliding dislocations and three types of γ γ domain boundaries or γ α_2 interface in a lamellar grain have been identified and resistance of the various domain boundaries or the interface to the propagation of twinning has been evaluated
文摘The fracture mechanism of lamellar Ti 49%Al alloy was investigated through studying the interactions between crack and lamellae or grain boundary. The results indicated that the nucleation and propagation mechanisms of crack depends on not only the lamellar orientations within grain but also the types of grain boundaries. When the angle between tensile axis and lamellae is relatively large, the main crack parallel to the lamellae propagates by nucleation, growth and linkage with interfacial microcracks. When the tensile axis is nearly parallel to the lamellae, the main crack perpendicular to the lamellae propagates by nucleation, growth and linkage with two types of microcracks, e.g. translamellar microcrack and interface delamination. In addition, the interlock grain boundary nearly parallel to the tensile axis is benefit to fracture toughness, the grain boundary nearly perpendicular to the tensile axis is bad for the toughness. [
文摘This work deals with determining the optimum thickness of the lamella wafer of silicon solar cell. The (p) base region makes up the bulk of the thickness of the wafer. This thickness has always been a factor limiting the performance of the solar cell, as it produces the maximum amount of electrical charges, contributing to the photocurrent. Determining the thickness of the wafer cannot be only mechanical. It takes into account the internal physical mechanisms of generation-diffusion-recombination of excess minority carriers. They are also influenced by external factors such as temperature and magnetic field. Under these conditions, magneto transport equation is required to be applied on excess minority carrier in lamella base silicon solar cell. It yields maximum diffusion coefficient which result on Lorentz law and Umklapp process. Then from photocurrent, back surface recombination velocity expressions are derived, both maximum diffusion coefficient and thickness dependent. The plot of the back surface recombination calibration curves as function of lamella width, leads to its maximum values, trough intercept points. Lamella optimum width is then obtained, both temperature and magnetic field dependent and expressed in relationships to show the required base thickness in the elaboration process.
基金supported by the grant from the Department of Biotechnology,Ministry of Science and Technology,India(Grant No.BT/PR18924/COE/34/48/2017).
文摘Exploration of novel genetic resources against root-knot nematode(RKN)is necessary to strengthen the resistance breeding program in cultivated rice,and investigations on the role of genotype-specific root anatomy in conferring a structural barrier against nematode invasion are largely underexplored.Here,we reported a highly-resistant rice germplasm Phule Radha that conferred remarkably lower RKN parasitic fitness in terms of reduced penetration and delayed development and reproduction when compared with susceptible cultivar PB1121.Using histological and biochemical analyses,we demonstrated that an enhanced suberin deposition in the exodermal root tip tissue of Phule Radha compared to PB1121 can effectively form a penetrative barrier against RKN infection,and this preformed barrier in the control tissue did not necessarily alter to a greater extent when challenged with RKN stress.Using qRT-PCR analysis,we showed that a number of suberin biosynthesis genes were greatly expressed in the exodermis of Phule Radha compared to PB1121.In sum,the present study established the role of rice exodermal barrier system in defense against an important soil-borne pathogen.
文摘AIM:To report the clinical outcomes of utilizing a three-layer flap and graft in reconstruction of the lower lid in one session.METHODS:Seventeen patients with total or near total lower eyelid defect were included.The defects were reconstructed in three layers.Posterior lamella was reconstructed by using tarsoconjunctival free graft from the ipsilateral upper lid and periosteal flap from lateral orbital rim.Mobilization of residual orbicularis muscle provided a rich blood supply;and the anterior lamella was reconstructed by skin flap prepared from upper lid blepharoplasty as a one-pedicular or bipedicular bucket handle flap.RESULTS:The cause of lower eyelid defect was basal cell carcinoma in 15 patients and trauma in two of them.No intraoperative and postoperative complication occurred.Patients were followed from 10 to 15mo postoperatively.Cosmetic results were favorable in all patients and we had acceptable functional results.Thickness of the reconstructed tissue was a concern in early postoperative period.CONCLUSION:Three-layer lower lid reconstruction in one session is an effective technique for total lower lid reconstruction with minimal complications and acceptable functional and aesthetic outcomes and can be considered as a safe alternative for the preexisting techniques.
文摘The silicon solar cell with series-connected vertical junction is studied with different lamella widths—the expression of the ac recombination velocity of the excess minority carrier at the back surface is established. Spectroscopy technique reveals dominated impact of the lamella widths of the base.
文摘Reconstructive surgery of the eyelid after tumor excision,trauma or other causes can be challenging,especially due to the complexities of the anatomic structures and to the necessity of both functional and aesthetic successful outcomes.The aim of this minireview was to investigate the use of tissue transplantation in eyelid reconstruction.Surgical procedures are various,based on the use of both flaps,pedicled or free,and grafts,in order to guarantee adequate tissue reconstruction and blood supply,which are necessary for correct healing.Common techniques normally include the use of local tissues,combining non-vascularized grafts with a vascularized flap for the two lamellae repair,to attempt a reconstruction similar to the original anatomy.When defects are too wide,vast,deep,and complex or when no adjacent healthy tissues are available,distant area tissues need to be recruited as free flaps or grafts and paired with mucosal layer reconstruction.With regards to the anterior lamella,full thickness skin grafts are commonly preferred.With regards to the reconstruction of posterior lamella,there are different graft options,which include conjunctival or tarsoconjunctival,mucosal or palatal or cartilaginous grafts usually combined with local flaps.Free flap transplantation,normally reserved for rare select cases,include the use of the radial forearm and anterolateral flaps combined with mucosal grafts,which are surgical options currently reported in the literature.
基金Projects(50771041,50801019)supported by the National Natural Science Foundation of ChinaProject(20080430909)supported by China Postdoctoral Science FoundationProject(HITQNJS.2008.018)supported by Development Program for Outstanding Young Teachers in Harbin Institute of Technology,China
文摘Using general multi-phase-field model,detailed microstructures corresponding to different initial lamellar sets were simulated in a binary eutectic alloy with an asymmetric phase diagram.The simulation results show that regular or unstable oscillating lamellar structures depend on the initial lamellar widths of two solid phases.A lamellar morphology map associating with the initial widths has been derived,which is capable of showing the condition of forming various lamella structures.For instance,a regular lamella was formed with fast solidification while large lamella resulted from disorder growth with low interfacial velocity. The investigated interface velocities indicate that with fast solidification to form regular lamella,a disorder growth manner or a large lamellar spacing causes a low interface velocity.These results are in good agreement with those proposed by Jackson-Hunt model.
文摘The rod-like assembly from BAB block copolymer with hydrophilic middle block A in aqueous solution was described. The copolymer used is polystyrene (PS)39-b-poly(4-vinylpyridine)(P4VP)98-b-PS39 (the subscripts are the average polymerization degree of corresponding blocks) triblock copolymer with Mw/Mn = 1.15. The aggregates were characterized by transmission electron microscopy and atomic force microscopy. The dependence of rod-like aggregate formation on solvents, pH, and polymer concentrations was investigated. The rod-like aggregates were formed when using dioxane as initial solvent, while spherical micelles were formed using DMF. Elevating pH values from 4 to 5 to 7 and decreasing initial copolymer concentrations from 1.5 wt% to 1.0 wt% to 0.5 wt% were favorable for the formation of well-defined rod-like aggregates. In addition, the bicontinuous rods and lamellae were observed when preparing colloid solutions in appropriate conditions.
文摘Microphase separation and lamellar structure of segmented polyether- and polyester-polyurethanes have been investigated by means of transmission electron microscopy with the ruthenium tetroxide staining technique. The results show that the RuO_4 staining technique is simpler and may give better image contrast than other staining methods for this polymer. Microphase separation and lamellar structure of segmented polyether-and polyester-polyurethanes were directly observed and discussed.
文摘The crystalline behavior of urethane substitute polydiacetylene was studied by using pohrized light and electron microscopy. The lamellar morphological structure was observed in the crystallized films. The thickness of lamellae is about 300A, being independent of the crystalline temperature. But the size and density of lamellae were dependent on the crystallization temperature. If the molten film was sheared during the crystallzation process the oriented lamellae grew with their long axes perpendicular to the direction of shear and the chain direction was normal to the lamellar surface.
基金Funded by the National Natural Science Foundation of China(No.11274027)Beijing Municipal Natural Science Foundation(No.2092005)。
文摘A novel Fe-enriched lamella sandwich phase (χ-phase) has been found to precipitate along the basal (0001)_(Mg) planes in the heat-treated Mg-Gd-Fe alloy and its structure is clearly revealed by means of atomic-resolution transmission electron microscopy.The layered χ-phase only has a thickness of mono-unit-cell and consists invariably of ten atomic layers stacking along the[0001]_(Mg) direction,of which the outermost atomic layers had larger in-plane atom-pillar spacing than the inner layers.Fe/Gd atoms are mainly enriched in the outer four atomic layers in the χ-phase,forming two structurally unsymmetrical four-layer shells to sandwich the middle two Mg layers.An atomic model has been proposed for this layered sandwich-structured χ-phase.
文摘Wild-type potato (Solanum tuberosum L.) plants and their transformants harboring agrobacterial rolB or rolC genes under control of the patatin class I promoter were cultured in vitro. These plants were used as a source of single-node stem cuttings. The structure of native starch in tubers formed on cuttings was determined using methods of X-ray scattering and differential scanning microcalorimetry (DSC). It was found that in starch from tubers of rolB plants the melting temperature of crystalline lamella was lower and their thickness was less than that in wild-type potato. In tubers of rolC plants starch differed from starch in wild-type plants by a higher melting temperature, reduced melting enthalpy, and a greater thickness of crystalline lamellae. The melting of starch from tubers of rolC plants proceeded as the melting of two independent crystalline structures with melting temperatures of 338.0°K and 342.8°K. Overall data show that starches of different structure can be obtained by using transgenic approach.
文摘We studied morphofunctional properties of human platelets, treated with low doses of hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>). It was shown that platelet incubation with 20 - 75 <em>μ</em>M H<sub>2</sub>O<sub>2</sub> during 24 hours at 20<span style="white-space:nowrap;">°</span>C - 22<span style="white-space:nowrap;">°</span>C did not cause visible structural deficiencies in cells. Platelets maintained their adhesion activity and velocity of degranulation at 20 <em>μ</em>M H<sub>2</sub>O<sub>2</sub>. 30 - 60 μM H<sub>2</sub>O<sub>2</sub> dose-dependently reduced lamella’s growth and allowed retaining granule bulk inside cytoplasm of spreading platelets. After 1 - 2 hours, the most effect of platelet granules’ stabilization was registered at samples, previously incubated with 60 μM H<sub>2</sub>O<sub>2</sub>. Adrenalin activation led to rapid degranulation of stabilized platelets, whereas lamella’s growth in activated platelets was low or medium.