Through the revelation of“commodity value”,the“invisible hand”described by Adam Smith is now clearly visible.It is precisely“commodity value”that guides people to seek benefits for themselves and for others,addi...Through the revelation of“commodity value”,the“invisible hand”described by Adam Smith is now clearly visible.It is precisely“commodity value”that guides people to seek benefits for themselves and for others,adding enormous wealth to society.展开更多
Objective To investigate the effect of invisible full-thickness mesh skin graft in the treatment of scar contracture deformity of the dorsal hand.Methods From January 2016 to February 2019,25 patients with cicatricial...Objective To investigate the effect of invisible full-thickness mesh skin graft in the treatment of scar contracture deformity of the dorsal hand.Methods From January 2016 to February 2019,25 patients with cicatricial contracture deformity of dorsal hand admitted to our hospital underwent full thickness skin graft.During the operation,the scar healed completely and the superficial fascia remained intact.The wound surface was transplanted with invisible mesh full thickness skin graft.The survival of the skin graft and the recovery of hand function and appearance in the later period were observed after the operation.Results The skin grafts of 20 patients survived with high quality,3 cases had partial epidermis exfoliation,and 2 cases had partial epidermis scattered in blisters.After intensive dressing change,all wounds healed and no complications occurred after the operation.The hand function and appearance of the patients were obviously improved.Conclusion The application of full thickness skin graft to correct scar deformity has the advantages of good functional and appearance recovery and difficult postoperative contracture.Invisible full-thickness mesh skin graft is one of the ideal methods to correct scar contracture deformity of the dorsal hand.展开更多
Ralph Ellison’s Invisible Man deals with the identity issue fundamental for black Americans to reestablish themselves in the white-dominated society.While the narrator suffers from identity crisis in multiples ways,t...Ralph Ellison’s Invisible Man deals with the identity issue fundamental for black Americans to reestablish themselves in the white-dominated society.While the narrator suffers from identity crisis in multiples ways,the paper focuses on the conflict between his need to build a distinctive individual identity with the prerequisite to surrender to collective identity in order to blend in the group.展开更多
To extract gold from a low-grade(13.43 g/t) and high-sulfur(39.94wt% sulfide sulfur) Carlin-type gold concentrate from the Nibao deposit, Guizhou, a bio-pretreatment followed by carbon-in-pulp(CIP) cyanide leaching pr...To extract gold from a low-grade(13.43 g/t) and high-sulfur(39.94wt% sulfide sulfur) Carlin-type gold concentrate from the Nibao deposit, Guizhou, a bio-pretreatment followed by carbon-in-pulp(CIP) cyanide leaching process was used. Various methods were used to detect the low-grade gold in the concentrate; however, only time-of-flight secondary-ion mass spectrometry(TOF-SIMS) was successful. With bio-pretreatment, the gold recovery rate increased by approximately 70.16% compared with that obtained by direct cyanide leaching of the concentrate. Various attempts were made to increase the final gold recovery rate. However, approximately 20wt% of the gold was non-extractable. To determine the nature of this non-extractable gold, mineralogy liberation analysis(MLA), formation of secondary product during the bio-pretreatment, and the preg-robbing capacity of the carbonaceous matter in the ore were investigated. The results indicated that at least four factors affected the gold recovery rate: gold occurrence, tight junctions of gold-bearing pyrite with gangue minerals, jarosite coating of the ore, and the carbonaceous matter content.展开更多
Invisible Man is Ralph Ellison's most important work,the hero of which is confused by the problem of his identity.This thesis will discuss the transformation of Mary Rambo in the novel.At the beginning,Mary Rambo ...Invisible Man is Ralph Ellison's most important work,the hero of which is confused by the problem of his identity.This thesis will discuss the transformation of Mary Rambo in the novel.At the beginning,Mary Rambo was a symbol of hope and encouragement for the hero and a kind of salvation and redemption to him both materially and spiritually.But later,she changed from a savior to a restrictive mother.The hero became restive and guilty under her watchful and anxious care.Thus,the hero must escape her in order to continue his search for identity.展开更多
BACKGROUND Mandibular retraction is the main etiological mechanism of class II malocclusion in China and the subsequent distal molar relationship can cause functional discomfort in mastication,breathing and the tempor...BACKGROUND Mandibular retraction is the main etiological mechanism of class II malocclusion in China and the subsequent distal molar relationship can cause functional discomfort in mastication,breathing and the temporomandibular joint.The use of mandibular advancement(MA)devices has recently emerged as an adolescent mandibular retraction treatment;however,current studies regarding the effect thereof are relatively few,and there is lack of sufficient clinical support.AIM To investigate the clinical effect of invisalign MA on the treatment of mandibular retraction in adolescents.METHODS This study included 30 adolescent patients who underwent treatment with the MA appliances from December 2017 to June 2021.The lateral cephalometric data before and after treatment were collected and imported into Dolphin Imaging software.The changes were measured by linear measurement superimposed with lateral cephalometric trajectory based on the Pancherz technology.RESULTS There was no significant difference in the length and position of maxilla before and after the treatment.The position of the mandible moved 3.13 mm,the length increased 4.14 mm,the mandibular ramus length increased 4.09 mm,the body length increased 4.25 mm,and the position of the condyle moved 1.03 mm forward after treatment.Additionally,changes in the incisor sagittal position and labial inclination were observed.The position of the upper incisor point moved back 1.33 mm,without statistical difference,the inclination and tooth angle decreased by 3.44°and 4.06°,respectively;the position of the lower incisor point was moved 2.98 mm,and the inclination and tooth angle increased by 2.62°and 1.23°,respectively.Furthermore,changes in the incisor overjet and molar relationship were seen.Overjet decreased by 4.31 mm,of which 1.78 mm was due to dental factors,accounting for 41.3%of the effect as opposed to 58.7%due to skeletal factors.Molar relationship improved 3.87 mm,with 1.34 mm due to dental factors,and dental and skeletal factors were accounted for 34.6%and 65.4%of the effect,respectively.CONCLUSION For adolescent patients with mandible retraction,invisalign MA can effectively promote the mandible growth,and it was proven to be mainly due to skeletal effects.展开更多
The African-American novel Invisible Man written by Ralph Ellison is about the miserable suffering of black people in the white society.The black people were invisible in the white world.This thesis analyzes this nove...The African-American novel Invisible Man written by Ralph Ellison is about the miserable suffering of black people in the white society.The black people were invisible in the white world.This thesis analyzes this novel from post-colonialism perspective to discuss the process of looking for the racial identity of the protagonist.展开更多
The method of designing electromagnetic invisible cloaks is usually based on the form-invariance of Maxwell's equations in coordinate transformation. The exterior boundary of a cylindrical invisible cloak is unchange...The method of designing electromagnetic invisible cloaks is usually based on the form-invariance of Maxwell's equations in coordinate transformation. The exterior boundary of a cylindrical invisible cloak is unchanged and the interior boundary is extended from that of a point to that of a cylindrical region in coordination transformation. This transformation process makes perfect cloaks, but it causes singularity in the constitutive material parameters of cloaks. This singularity makes the cloaks impossible to realize in practice. In order to remove this singularity, this paper sets a small cylindrical region replacing a point in the space transformation. The cylindrical region is so small that it does not affect the invisibility effects, but it can remove the singularity for material parameters. Full wave simulations based on the finite element method were used to verify the designed cloaks.展开更多
Based on the theory of phase complement, an anti-cloak with circular cross section can be made invisible to an object outside its domain. As the cloak with elliptic cross section is more effective to make objects invi...Based on the theory of phase complement, an anti-cloak with circular cross section can be made invisible to an object outside its domain. As the cloak with elliptic cross section is more effective to make objects invisible than that with circular cross section, a scaled coordinate system is proposed to design equivalent materials of invisible anti- cloak with elliptic cross section using phase complement. The cloaks with conventional dielectric and double negative parameters are both simulated with the geometrical transformations. The results show that the cloak with elliptic cross section through phase complement can effectively hide the outside objects.展开更多
This paper reports that a general method of designing invisible cloaks is using variant constitutive material parameters to realize the space transformation. A hollow region can be hidden after this transformation. It...This paper reports that a general method of designing invisible cloaks is using variant constitutive material parameters to realize the space transformation. A hollow region can be hidden after this transformation. It was recently shown (Ma H, Qu S B, Xu Z and Wang J F 2009 Appl. Phys. Lett. 94 103501) that when the original point moves to the boundary of a cloak, the cloak can be designed to be open. Based on this theory, we propose multi-window invisible cloaks which can conceal a group of objects. Full wave simulations for invisible cloaks with regular and irregular shapes verified this method.展开更多
We present the design and the experimental demonstration of an invisible cloak with irregular shape by using tensor transmission line(TL) metamaterials. The fabricated cloak consists of tensor TL unit cells exhibiti...We present the design and the experimental demonstration of an invisible cloak with irregular shape by using tensor transmission line(TL) metamaterials. The fabricated cloak consists of tensor TL unit cells exhibiting anisotropic effective material parameters, while the background medium consists of isotropic TL unit cells. The simulated and the measured field patterns around the cloak show a fairly good agreement, both demonstrate that the fabricated cloak can shield the cloaked interior area from electromagnetic fields without perturbing the external fields. The scattering of the cloaked perfect electric conductor(PEC) is minimized. Furthermore, the nonresonant property of the TL structure results in a relatively broad bandwidth of the realized cloak, which is clearly observed in our experiment.展开更多
Two-dimensional (2D) elliptically cylindrical invisible cloaks with multiple regions are designed based on the trans-formation optics and the complementary media theory. Multiple invisible cloak regions can be obtai...Two-dimensional (2D) elliptically cylindrical invisible cloaks with multiple regions are designed based on the trans-formation optics and the complementary media theory. Multiple invisible cloak regions can be obtained by properly using the compressed or folded transformation in each space layer. The constitutive parameter tensor expressions for each re- gion have been obtained. The results of full wave simulations by using finite element software confirm the validity of the constitutive parameter tensor expressions. In addition, the parameters are relatively easier to realize.展开更多
The new designed curtain fabric,whose two faces were covered by trilobal cross-sectional filament and dull polyester filament,was designed with three-bar tricot stitch,which possessed unique style with implicit grid e...The new designed curtain fabric,whose two faces were covered by trilobal cross-sectional filament and dull polyester filament,was designed with three-bar tricot stitch,which possessed unique style with implicit grid effects.Tricot two-sided technology was adopted in this paper and the method of spectrophotometer was used to test the optical properties,including the light transmittance and reflectance of the technical face and back side of the samples in the ultraviolet,visible,and near-infrared band.The results show that the transmittance and invisible,anti-ultraviolet properties in the thin and single-layer fabric are improved.The fabric meets the qualifications in use of curtain material.展开更多
文摘Through the revelation of“commodity value”,the“invisible hand”described by Adam Smith is now clearly visible.It is precisely“commodity value”that guides people to seek benefits for themselves and for others,adding enormous wealth to society.
文摘Objective To investigate the effect of invisible full-thickness mesh skin graft in the treatment of scar contracture deformity of the dorsal hand.Methods From January 2016 to February 2019,25 patients with cicatricial contracture deformity of dorsal hand admitted to our hospital underwent full thickness skin graft.During the operation,the scar healed completely and the superficial fascia remained intact.The wound surface was transplanted with invisible mesh full thickness skin graft.The survival of the skin graft and the recovery of hand function and appearance in the later period were observed after the operation.Results The skin grafts of 20 patients survived with high quality,3 cases had partial epidermis exfoliation,and 2 cases had partial epidermis scattered in blisters.After intensive dressing change,all wounds healed and no complications occurred after the operation.The hand function and appearance of the patients were obviously improved.Conclusion The application of full thickness skin graft to correct scar deformity has the advantages of good functional and appearance recovery and difficult postoperative contracture.Invisible full-thickness mesh skin graft is one of the ideal methods to correct scar contracture deformity of the dorsal hand.
文摘Ralph Ellison’s Invisible Man deals with the identity issue fundamental for black Americans to reestablish themselves in the white-dominated society.While the narrator suffers from identity crisis in multiples ways,the paper focuses on the conflict between his need to build a distinctive individual identity with the prerequisite to surrender to collective identity in order to blend in the group.
基金financially supported by the National Science and Technology Supporting Program (No. 2012BAB10B08)the National High Technology Research and Development Program of China (No. 2012AA060501)
文摘To extract gold from a low-grade(13.43 g/t) and high-sulfur(39.94wt% sulfide sulfur) Carlin-type gold concentrate from the Nibao deposit, Guizhou, a bio-pretreatment followed by carbon-in-pulp(CIP) cyanide leaching process was used. Various methods were used to detect the low-grade gold in the concentrate; however, only time-of-flight secondary-ion mass spectrometry(TOF-SIMS) was successful. With bio-pretreatment, the gold recovery rate increased by approximately 70.16% compared with that obtained by direct cyanide leaching of the concentrate. Various attempts were made to increase the final gold recovery rate. However, approximately 20wt% of the gold was non-extractable. To determine the nature of this non-extractable gold, mineralogy liberation analysis(MLA), formation of secondary product during the bio-pretreatment, and the preg-robbing capacity of the carbonaceous matter in the ore were investigated. The results indicated that at least four factors affected the gold recovery rate: gold occurrence, tight junctions of gold-bearing pyrite with gangue minerals, jarosite coating of the ore, and the carbonaceous matter content.
文摘Invisible Man is Ralph Ellison's most important work,the hero of which is confused by the problem of his identity.This thesis will discuss the transformation of Mary Rambo in the novel.At the beginning,Mary Rambo was a symbol of hope and encouragement for the hero and a kind of salvation and redemption to him both materially and spiritually.But later,she changed from a savior to a restrictive mother.The hero became restive and guilty under her watchful and anxious care.Thus,the hero must escape her in order to continue his search for identity.
基金This study was reviewed and approved by the Medical Ethics Committee of The Affiliated Hospital of Qingdao University(authorisation number:QYFYWZLL26729).
文摘BACKGROUND Mandibular retraction is the main etiological mechanism of class II malocclusion in China and the subsequent distal molar relationship can cause functional discomfort in mastication,breathing and the temporomandibular joint.The use of mandibular advancement(MA)devices has recently emerged as an adolescent mandibular retraction treatment;however,current studies regarding the effect thereof are relatively few,and there is lack of sufficient clinical support.AIM To investigate the clinical effect of invisalign MA on the treatment of mandibular retraction in adolescents.METHODS This study included 30 adolescent patients who underwent treatment with the MA appliances from December 2017 to June 2021.The lateral cephalometric data before and after treatment were collected and imported into Dolphin Imaging software.The changes were measured by linear measurement superimposed with lateral cephalometric trajectory based on the Pancherz technology.RESULTS There was no significant difference in the length and position of maxilla before and after the treatment.The position of the mandible moved 3.13 mm,the length increased 4.14 mm,the mandibular ramus length increased 4.09 mm,the body length increased 4.25 mm,and the position of the condyle moved 1.03 mm forward after treatment.Additionally,changes in the incisor sagittal position and labial inclination were observed.The position of the upper incisor point moved back 1.33 mm,without statistical difference,the inclination and tooth angle decreased by 3.44°and 4.06°,respectively;the position of the lower incisor point was moved 2.98 mm,and the inclination and tooth angle increased by 2.62°and 1.23°,respectively.Furthermore,changes in the incisor overjet and molar relationship were seen.Overjet decreased by 4.31 mm,of which 1.78 mm was due to dental factors,accounting for 41.3%of the effect as opposed to 58.7%due to skeletal factors.Molar relationship improved 3.87 mm,with 1.34 mm due to dental factors,and dental and skeletal factors were accounted for 34.6%and 65.4%of the effect,respectively.CONCLUSION For adolescent patients with mandible retraction,invisalign MA can effectively promote the mandible growth,and it was proven to be mainly due to skeletal effects.
文摘The African-American novel Invisible Man written by Ralph Ellison is about the miserable suffering of black people in the white society.The black people were invisible in the white world.This thesis analyzes this novel from post-colonialism perspective to discuss the process of looking for the racial identity of the protagonist.
基金Project supported partly by the National Natural Science Foundation of China (Grant Nos.50632030,10474077,and 60871027)partly by the National Basic Research Program of China (Grant No.2009CB613306)partly by the Natural Science Foundation of Shaanxi Province,China (Grant No.SJ08F01)
文摘The method of designing electromagnetic invisible cloaks is usually based on the form-invariance of Maxwell's equations in coordinate transformation. The exterior boundary of a cylindrical invisible cloak is unchanged and the interior boundary is extended from that of a point to that of a cylindrical region in coordination transformation. This transformation process makes perfect cloaks, but it causes singularity in the constitutive material parameters of cloaks. This singularity makes the cloaks impossible to realize in practice. In order to remove this singularity, this paper sets a small cylindrical region replacing a point in the space transformation. The cylindrical region is so small that it does not affect the invisibility effects, but it can remove the singularity for material parameters. Full wave simulations based on the finite element method were used to verify the designed cloaks.
基金supported by the National Natural Science Foundation of China (Grant No. 60871070)the Fundamental Research Funds for the Central Universities,China
文摘Based on the theory of phase complement, an anti-cloak with circular cross section can be made invisible to an object outside its domain. As the cloak with elliptic cross section is more effective to make objects invisible than that with circular cross section, a scaled coordinate system is proposed to design equivalent materials of invisible anti- cloak with elliptic cross section using phase complement. The cloaks with conventional dielectric and double negative parameters are both simulated with the geometrical transformations. The results show that the cloak with elliptic cross section through phase complement can effectively hide the outside objects.
基金Project supported partly by the National Natural Science Foundation of China (Grant Nos.50632030,10474077,and 60871027)partly by the National Basic Research Program of China (Grant No.2009CB613306)partly by the Natural Science Foundation of Shaanxi Province,China (Grant No.SJ08F01)
文摘This paper reports that a general method of designing invisible cloaks is using variant constitutive material parameters to realize the space transformation. A hollow region can be hidden after this transformation. It was recently shown (Ma H, Qu S B, Xu Z and Wang J F 2009 Appl. Phys. Lett. 94 103501) that when the original point moves to the boundary of a cloak, the cloak can be designed to be open. Based on this theory, we propose multi-window invisible cloaks which can conceal a group of objects. Full wave simulations for invisible cloaks with regular and irregular shapes verified this method.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11174280,60990323,and 60990320)the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.YYYJ-1123)
文摘We present the design and the experimental demonstration of an invisible cloak with irregular shape by using tensor transmission line(TL) metamaterials. The fabricated cloak consists of tensor TL unit cells exhibiting anisotropic effective material parameters, while the background medium consists of isotropic TL unit cells. The simulated and the measured field patterns around the cloak show a fairly good agreement, both demonstrate that the fabricated cloak can shield the cloaked interior area from electromagnetic fields without perturbing the external fields. The scattering of the cloaked perfect electric conductor(PEC) is minimized. Furthermore, the nonresonant property of the TL structure results in a relatively broad bandwidth of the realized cloak, which is clearly observed in our experiment.
基金Project supported by the National Natural Science Foundation of China(Grant No.61078060)the Innovative Research Team Program of Ningbo,China(Grant No.2009B21007)the K.C.Wong Magna Fund in Ningbo University,China
文摘Two-dimensional (2D) elliptically cylindrical invisible cloaks with multiple regions are designed based on the trans-formation optics and the complementary media theory. Multiple invisible cloak regions can be obtained by properly using the compressed or folded transformation in each space layer. The constitutive parameter tensor expressions for each re- gion have been obtained. The results of full wave simulations by using finite element software confirm the validity of the constitutive parameter tensor expressions. In addition, the parameters are relatively easier to realize.
基金Science and Technology Project of Zhejiang Province of China(No.2006C31018)
文摘The new designed curtain fabric,whose two faces were covered by trilobal cross-sectional filament and dull polyester filament,was designed with three-bar tricot stitch,which possessed unique style with implicit grid effects.Tricot two-sided technology was adopted in this paper and the method of spectrophotometer was used to test the optical properties,including the light transmittance and reflectance of the technical face and back side of the samples in the ultraviolet,visible,and near-infrared band.The results show that the transmittance and invisible,anti-ultraviolet properties in the thin and single-layer fabric are improved.The fabric meets the qualifications in use of curtain material.