The similar densities of dark matter and baryons in the universe imply that they may arise from the same ultraviolet model.B-Mesogenesis,which assumes dark matter is charged under the baryon number,attempts to simulta...The similar densities of dark matter and baryons in the universe imply that they may arise from the same ultraviolet model.B-Mesogenesis,which assumes dark matter is charged under the baryon number,attempts to simultaneously explain the origin of baryon asymmetry and dark matter in the universe.In particular,B-Mesogenesis may induce bottom-baryon decays into invisible or semi-invisible final states,which provide a distinctive signal for probing this scenario.In this work,we systematically study the invisible decays of bottom baryons into dark matter and the semi-invisible decays of bottom baryons into a meson or a photon together with a dark matter particle.In particular,the fully invisible decay can reveal the stable particles in B-Mesogenesis.Some QCD-based frameworks are used to calculate the hadronic matrix elements under the B-Mesogenesis model.We estimate the constraints on the Wilson coefficients or the product of some new physics couplings with the Wilson coefficients according to the semi-invisible and invisible decays of bottom baryons detectable at future colliders.展开更多
BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during or...BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during orthodontic treatment,an immediate pause of orthodontic adjustments is recommended;the treatment can resume when the symptoms are managed and stabilized.CASE SUMMARY This case report presents a patient(26-year-old,female)with angle class I,skeletal class II and TMDs.The treatment was a hybrid of clear aligners,fixed appliances and temporary anchorage devices(TADs).After 3 mo resting and treatment on her TMD,the patient’s TMD symptom alleviated,but her anterior occlusion displayed deep overbite.Therefore,the fixed appliances with TAD were used to correct the anterior deep-bite and level maxillary and mandibular deep curves.After the levelling,the patient showed dual bite with centric relation and maximum intercuspation discrepancy on her occlusion.After careful examination of temporomandibular joints(TMJ)position,the stable bite splint and Invisible Mandibular Advancement appliance were used to reconstruct her occlusion.Eventually,the improved facial appearance and relatively stable occlusion were achieved.The 1-year follow-up records showed there was no obvious change in TMJ morphology,and her occlusion was stable.CONCLUSION TMD screening and monitoring is of great clinical importance in the TMD susceptible patients.Hybrid treatment with clear aligners and fixed appliances and TADs is an effective treatment modality for the complex cases.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
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
Photo-stimuli responsive materials show great potential in the fields of information encryption and storage due to their distinctive spatial or temporal color changes.However,the conventional single or multi-color sta...Photo-stimuli responsive materials show great potential in the fields of information encryption and storage due to their distinctive spatial or temporal color changes.However,the conventional single or multi-color static outputs by light stimulus difficulty meet practical requirements for high-security optical storage technologies.Here,a novel dynamic irradiation-responsive phosphor of Na_(2)Ba_(2)Si_(2)O_(7):Eu is demonstrated,exhibiting high storage stability and convenient readout behaviors.The inherent Eu^(2+)luminescence can be dynamically tuned,instantly read out,and conveniently erased by controlling irradiation duration of a portable diode laser(365 nm).The modulation mechanism is unraveled by optically induced oxidation reactions of Eu^(2+)→Eu^(3+)and defects as killer centers.The excellent luminescence modulation degree(ΔR_(t)=89.5%)and the accompanying larger color contrast enable the creation of invisible optical codes with multi-level encryption in bright or dark field.These results indicate potential applications of Na_(2)Ba_(2)Si_(2)O_(7):-based materials in information encryption and invisible optical storage,and are expected to expand more investigations on optically induced PL modulation behaviors based on mixed valences and defects.展开更多
Invisible orthodontic treatment is an effective form of malocclusion treatment favored in recent years.The magnitude of its orthodontic force has a crucial impact on the outcome of the treatment and has gained a high ...Invisible orthodontic treatment is an effective form of malocclusion treatment favored in recent years.The magnitude of its orthodontic force has a crucial impact on the outcome of the treatment and has gained a high level of clinical interest.However,there are very few explorations of in vivo measurements of orthodontic force,and existing studies are limited to a large number of couplings,which are inconvenient for clinical use.In this work,we developed a wireless flexible measurement system that allows quantitative measurement of the orthodontic force of an invisible aligner on a dental model.The system is wireless,tiny,flexible,fast responding,and has a range suitable for the range of orthodontic forces.We show the difference in the orthodontic force applied to different tooth positions and the difference in the orthodontic force applied to different positions of the same tooth.In addition,the system can evaluate the mechanical differences between aligners of different brands and materials as well as the deviation of fabrication results.This system provides a test tool and evaluation method for future real-time assessment of clinical orthodontic forces.展开更多
Mn-doped all-inorganic perovskite quantum dots (QDs) provide prominent applications in the fields of low-cost light source or display,because of their remarkable properties including dual-color emission and reduced le...Mn-doped all-inorganic perovskite quantum dots (QDs) provide prominent applications in the fields of low-cost light source or display,because of their remarkable properties including dual-color emission and reduced lead content,as well as high photoluminescence quantum yields (PLQYs) and high stability.However,the existing synthesis approaches usually require hash conditions,such as high temperature and nitrogen protection,which is a major hurdler for the practical manufacturing.In addition,the significantly high Mn substitution ratio in CsPbX3 QDs is still challenging.The real dual-color emission with two strong emission peaks in the Mn-doped all-inorganic perovskite QDs has attracted great interest.Here we present a gram-scale approach to synthesize both CsPbxMn1-xCI3 and CsPb1-xMnxClyBr3-y QDs at 100 ℃ in the air with high Mn substitution ratio,up to 55.64% atomically.The as-prepared CsPb1-xMnxClyBr3-y QDs exhibit high PLQYs of 62.41% and dual-color emission with two strong emission peaks around at 400-450 nm and 600 nm,respectively.The enhanced peak at 400-450 nm is a result of the hybrid halides in CsPbBrxCl3-x host.Furthermore,the unique advantage of the optical emission and high PLQYs properties of the CsPbxMn1-xCl3 QDs has been demonstrated as invisible ink for encryption applications and polymer composites.Our gram-scale synthesis approach for Mn-doped all-inorganic perovskite QDs may boost the future research and practical applications of QDs-based white LED,spintronics,and molecular barcoding.展开更多
基金Supported by the National Key Research and Development Program of China(2020YFA0406400,2023YFA1606000)the National Natural ScienceFoundationof China(12335003,12275277)。
文摘The similar densities of dark matter and baryons in the universe imply that they may arise from the same ultraviolet model.B-Mesogenesis,which assumes dark matter is charged under the baryon number,attempts to simultaneously explain the origin of baryon asymmetry and dark matter in the universe.In particular,B-Mesogenesis may induce bottom-baryon decays into invisible or semi-invisible final states,which provide a distinctive signal for probing this scenario.In this work,we systematically study the invisible decays of bottom baryons into dark matter and the semi-invisible decays of bottom baryons into a meson or a photon together with a dark matter particle.In particular,the fully invisible decay can reveal the stable particles in B-Mesogenesis.Some QCD-based frameworks are used to calculate the hadronic matrix elements under the B-Mesogenesis model.We estimate the constraints on the Wilson coefficients or the product of some new physics couplings with the Wilson coefficients according to the semi-invisible and invisible decays of bottom baryons detectable at future colliders.
基金Natural Science Foundation of Jiangsu Province, No. SBK2021021787the Major Project of the Health Commission ofJiangsu Province, No. ZD2022025and the Key Project of the Nanjing Health Commission, No. ZKX20048.
文摘BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during orthodontic treatment,an immediate pause of orthodontic adjustments is recommended;the treatment can resume when the symptoms are managed and stabilized.CASE SUMMARY This case report presents a patient(26-year-old,female)with angle class I,skeletal class II and TMDs.The treatment was a hybrid of clear aligners,fixed appliances and temporary anchorage devices(TADs).After 3 mo resting and treatment on her TMD,the patient’s TMD symptom alleviated,but her anterior occlusion displayed deep overbite.Therefore,the fixed appliances with TAD were used to correct the anterior deep-bite and level maxillary and mandibular deep curves.After the levelling,the patient showed dual bite with centric relation and maximum intercuspation discrepancy on her occlusion.After careful examination of temporomandibular joints(TMJ)position,the stable bite splint and Invisible Mandibular Advancement appliance were used to reconstruct her occlusion.Eventually,the improved facial appearance and relatively stable occlusion were achieved.The 1-year follow-up records showed there was no obvious change in TMJ morphology,and her occlusion was stable.CONCLUSION TMD screening and monitoring is of great clinical importance in the TMD susceptible patients.Hybrid treatment with clear aligners and fixed appliances and TADs is an effective treatment modality for the complex cases.
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.
基金the National Natural Science Foundation of China(Nos.52062042 and 12164005)the Central Government Guidance Funds for Local Scientific and Technological Development of China(No.Guike ZY22096024).
文摘Photo-stimuli responsive materials show great potential in the fields of information encryption and storage due to their distinctive spatial or temporal color changes.However,the conventional single or multi-color static outputs by light stimulus difficulty meet practical requirements for high-security optical storage technologies.Here,a novel dynamic irradiation-responsive phosphor of Na_(2)Ba_(2)Si_(2)O_(7):Eu is demonstrated,exhibiting high storage stability and convenient readout behaviors.The inherent Eu^(2+)luminescence can be dynamically tuned,instantly read out,and conveniently erased by controlling irradiation duration of a portable diode laser(365 nm).The modulation mechanism is unraveled by optically induced oxidation reactions of Eu^(2+)→Eu^(3+)and defects as killer centers.The excellent luminescence modulation degree(ΔR_(t)=89.5%)and the accompanying larger color contrast enable the creation of invisible optical codes with multi-level encryption in bright or dark field.These results indicate potential applications of Na_(2)Ba_(2)Si_(2)O_(7):-based materials in information encryption and invisible optical storage,and are expected to expand more investigations on optically induced PL modulation behaviors based on mixed valences and defects.
基金Beijing Natural Science Foundation(L232109)National Natural Science Foundation of China(No.12202274 and No.52171234)+1 种基金Fundamental Research Funds for the Central Universities(YWF-22-K-101)National Key Research and Development Project(Nos.2021YFC2400703 and 2019YFE0101100).
文摘Invisible orthodontic treatment is an effective form of malocclusion treatment favored in recent years.The magnitude of its orthodontic force has a crucial impact on the outcome of the treatment and has gained a high level of clinical interest.However,there are very few explorations of in vivo measurements of orthodontic force,and existing studies are limited to a large number of couplings,which are inconvenient for clinical use.In this work,we developed a wireless flexible measurement system that allows quantitative measurement of the orthodontic force of an invisible aligner on a dental model.The system is wireless,tiny,flexible,fast responding,and has a range suitable for the range of orthodontic forces.We show the difference in the orthodontic force applied to different tooth positions and the difference in the orthodontic force applied to different positions of the same tooth.In addition,the system can evaluate the mechanical differences between aligners of different brands and materials as well as the deviation of fabrication results.This system provides a test tool and evaluation method for future real-time assessment of clinical orthodontic forces.
基金supported by the National Key Research and Development Program of China (No.2018YFB1105100)the National Natural Science Foundation of China (Nos.51572096 and 61704061).
文摘Mn-doped all-inorganic perovskite quantum dots (QDs) provide prominent applications in the fields of low-cost light source or display,because of their remarkable properties including dual-color emission and reduced lead content,as well as high photoluminescence quantum yields (PLQYs) and high stability.However,the existing synthesis approaches usually require hash conditions,such as high temperature and nitrogen protection,which is a major hurdler for the practical manufacturing.In addition,the significantly high Mn substitution ratio in CsPbX3 QDs is still challenging.The real dual-color emission with two strong emission peaks in the Mn-doped all-inorganic perovskite QDs has attracted great interest.Here we present a gram-scale approach to synthesize both CsPbxMn1-xCI3 and CsPb1-xMnxClyBr3-y QDs at 100 ℃ in the air with high Mn substitution ratio,up to 55.64% atomically.The as-prepared CsPb1-xMnxClyBr3-y QDs exhibit high PLQYs of 62.41% and dual-color emission with two strong emission peaks around at 400-450 nm and 600 nm,respectively.The enhanced peak at 400-450 nm is a result of the hybrid halides in CsPbBrxCl3-x host.Furthermore,the unique advantage of the optical emission and high PLQYs properties of the CsPbxMn1-xCl3 QDs has been demonstrated as invisible ink for encryption applications and polymer composites.Our gram-scale synthesis approach for Mn-doped all-inorganic perovskite QDs may boost the future research and practical applications of QDs-based white LED,spintronics,and molecular barcoding.
