Navigating the Challenges of Emerging Contaminants to Protect Human and Ecological Health

Emerging contaminants are defined as chemicals that are not currently(or have only recently been)regulated and about which there are concerns regarding their impact on human or ecological health.Such contaminants are widely detected in air,water,soil,sediment,and biotic environments.It is against this backdrop of urgency that we have curated this special issue titled“Emerging Contaminants Control:Science and Technology,”with the goal of uniting the latest scientific insights and pioneering strategies to address this global concern.This special issue embarks on a comprehensive examination of the emerging contaminants dilemma,covering aspects such as risk assessment,remediation technologies,environmental surveying,and the broader implications for policy.Through a collection of articles,we probe deep into the core of this issue,showcasing studies that range from appraising environmental risks to forging new methods for treatment and scrutinizing the occurrence of contaminants across different environmental settings.

Long-term Integration Ability of the Submillimeter Wave Astronomy Satellite(SWAS)Spectral Line Receivers

The Submillimeter Wave Astronomy Satellite(SWAS)was the first space telescope capable of high spectral resolution observations of terahertz spectral lines.We have investigated the integration ability of its two receivers and spectrometer during five and a half years of on-orbit operation.The CI,O_(2),H_(2)O,and^(13)CO spectra taken toward all observed Galactic sources were analyzed.The present results are based on spectra with a total integration time of up to 2.72×10~4hr(■10~8s).The noise in the spectra is generally consistent with that expected from the radiometer equation,without any sign of approaching a noise floor.This noise performance reflects the extremely stable performance of the passively cooled front end as well as other relevant components in the SWAS instrument throughout its mission lifetime.

The ALMA-QUARKS Survey.Ⅱ.The ACA 1.3 mm Continuum Source Catalog and the Assembly of Dense Gas in Massive Star-Forming Clumps

Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures”,is observing 139 massive starforming clumps at ALMA Band 6(λ~1.3 mm).This paper introduces the Atacama Compact Array(ACA)7 m data of the QUARKS survey,describing the ACA observations and data reduction.Combining multiwavelength data,we provide the first edition of QUARKS atlas,offering insights into the multiscale and multiphase interstellar medium in high-mass star formation.The ACA 1.3 mm catalog includes 207 continuum sources that are called ACA sources.Their gas kinetic temperatures are estimated using three formaldehyde transitions with a non-LTE radiation transfer model,and the mass and density are derived from a dust emission model.The ACA sources are massive(16–84 percentile values of 6–160 M_(⊙)),gravity-dominated(M∝R^(1.1))fragments within massive clumps,with supersonic turbulence(M>1)and embedded star-forming protoclusters.We find a linear correlation between the masses of the fragments and the massive clumps,with a ratio of 6%between the two.When considering fragments as representative of dense gas,the ratio indicates a dense gas fraction(DGF)of 6%,although with a wide scatter ranging from 1%to 10%.If we consider the QUARKS massive clumps to be what is observed at various scales,then the size-independent DGF indicates a self-similar fragmentation or collapsing mode in protocluster formation.With the ACA data over four orders of magnitude of luminosity-to-mass ratio(L/M),we find that the DGF increases significantly with L/M,which indicates clump evolutionary stage.We observed a limited fragmentation at the subclump scale,which can be explained by a dynamic global collapse process.

Linking Groundwater Quality and Quantity： An Assessment of Satellite-Based Groundwater Storage Anomalies from GRACE against Ground Measurements of Contaminants in California

Groundwater comprises a large portion of irrigation for California＇s agriculture, and sustains a wide diversity of ecosystems as well as consumptive use, but pumping is occurring faster than replenishment. At the same time, contaminants from fertilizers and pesticides are infiltrating into the groundwater, becoming increasingly concentrated as water is extracted. It compared space-based observations of groundwater anomalies from California＇s San Joaquin Valley using the GRACE （gravity recovery and climate experiment） against measurements of 42 organic and inorganic chemicals from 41,667 wells in the valley from 2003 to 2010. It compared Arsenic, Boron, Cadmium, Chloride, Selenium, Trichloroethylene, and TDS （total dissolved solid） concentrations with the groundwater storage anomaly from 2003 to 2010. The results show strong correlations for groundwater depletion against increasing chloride （r2= 0.78, p 〈 0.05） and boron （r2 = 0.88, p 〈 0.05）. This indicates increasing contaminant concentrations while groundwater was depleting over the last eight years. Solubilization by complexation with Cl, CO3 and/or organic chelates may account for the increasing concentration of some heavy metals when groundwater depletion occurs. These results are the first to link space-based groundwater mass change with groundwater contaminant concentration change.

Introduction to the special issue on celebrating the 15th anniversary of JIOHS and the 70th anniversary of HUST

Since launching in 2008,Journal of Innovative Optical Health Sciences(JIOHS)has been published for 15 years umtil 2022.Supported by the founding advisor Prof.Britton Chance and other founding Editorial Members,JIOHS was quickly embraced by the biomedical optics community,especially in Asia.Authors submitted some of their high quality papers to JIOHS,which led to a constant Impact Factor(IF)increase frcom the first IF 0.632 to IF 2396(Journal Citation Report 2021).

Prevalence and risk factors of infertility in a Mongolian population

Objective:To investigate and analyze the prevalence and risk factors of infertility in a Mongolian population.Methods:We conducted a population-based cross-sectional study between September 2016 and November 2021.Our study population of 1919 participants consisted of residents of Ulaanbaatar city and four regions of Mongolia.A pretested standardized and structured questionnaire was used to gather data from the participants.Our questionnaire comprised categories influencing infertility,such as socioeconomic status,lifestyle factors,health,reproductive history,present status,and sexual function.In addition,trained staff conducted face-to-face interviews with the participants.Results:Our study showed an infertility incidence of 8.2%,with primary infertility at 2.76%and secondary infertility at 5.47%.Compared with the urban area of Ulaanbaatar,the prevalence of infertility was significantly higher amongst the rural population(P<0.001).Risk factors of infertility included advanced age(35-39 years,OR 1.8,95%CI 1.99-6.55;>40 years,OR 2.1,95%CI 2.62-8.55),living rural region(aOR 2.4,95%CI 1.62-3.69),alcohol consumption(aOR 1.6,95%CI 1.11-2.44),chronic diseases(aOR 1.6,95%CI 1.20-2.38),reproductive disease(aOR 2.6,95%CI 1.86-3.88),gynecological operative history(aOR 2.1,95%CI 1.38-3.21),ovarian cyst(aOR 4.2,95%CI 2.70-6.40),gonorrhea(aOR 2.4,95%CI 1.01-6.16),non-malignant uterine cancer(aOR 2.9,95%CI 1.40-6.70),and endometriosis(aOR 4.7,95%CI 1.41-15.62).Conclusions:In Mongolia,the average infertility rate is 8.2%,similar to the average worldwide and is significantly higher in rural communities.Our study shows the most significant risk factors for infertility are age,alcohol consumption,and rural living.In addition,an unfavorable gynecological history and some diseases also pose a risk to fertility.

Updated Inventory of Carbon Monoxide in the Taurus Molecular Cloud

The most extensive survey of carbon monoxide(CO)gas in the Taurus molecular cloud relied on ^(12)CO and ^(13)CO J=1→0 emission only,distinguishing the region where ^(12)CO is detected without ^(13)CO(named mask 1 region)from the one where both are detected(mask 2 region)(Goldsmith et al.2008;Pineda et al.2010).We have taken advantage of recent ^(12)CO J=3→2 James Clerk Maxwell Telescope observations,where they include mask 1regions to estimate density,temperature,and N(CO)with a large velocity gradient model.This represents 1395 pixels out of~1.2 million in the mark 1 region.Compared to Pineda et al.(2010)results and assuming a Tkin of 30 K,we find a higher volume density of molecular hydrogen of 3.3×10^(3) cm^(-3),compared to their 250-700 cm^(-3),and a CO column density of 5.7×10^(15)cm^(-2),about a quarter of their value.The differences are important and show the necessity to observe several CO transitions to better describe the intermediate region between the dense cloud and the diffuse atomic medium.Future observations to extend the ^(12)CO J=3→2 mapping further away from the ^(13)COdetected region comprising mask 1 are needed to revisit our understanding of the diffuse portions of dark clouds.

Simulating the Stress-Strain Response of Building under Oscillating Wind Conditions

Wind load is one of the main lateral control loads that need to be considered in the design of high-rise building structures. It is also of great engineering significance to study the influence of static wind load or time-varying wind load on the dynamic response of structures. In this paper, a high-rise building with a rectangular section (46.8 m × 27 m × 33 m) is simulated based on Ansys18.0 APDL software. The real situation of its response under no lateral wind load and different fluctuating wind load conditions is simulated and the stress and strain response of the building under steady-state and time-varying wind load is given. The results show that the upper strain of the structure under wind load is about 1/1000 of the bottom strain, and the strain of the structure shows obvious accumulation from the top to the bottom, that is, the bottom strain of the building will be higher than the top strain. The influence of time-varying wind load on building structure is related to the loading position of wind load on the structure. The results provide a basis for the structural wind resistance design of this type of building.

Molecular Oxygen Abundance in Galactic Massive Star Formation Regions Based on SWAS Observations

Molecular oxygen abundance is a key parameter in understanding the chemical network of the interstellar medium.We estimate the molecular oxygen column density and abundance for a sample of Galactic massive star formation regions based on observations from the Submillimiter Wave Astronomy Satellite(SWAS)survey.We obtained an averaged O_(2)spectrum based on this sample using the(SWAS)survey data(O_(2),487.249 GHz,N=3-1,J=3-2).No emission or absorption feature is seen around the supposed central velocity with a total integration time of t_(total)=8.67×10^(3)hr and an rms noise per channel of 1.45 m K.Assuming a kinetic temperature T_(kin)=30 K,we derive the 3σupper limit of the O_(2)column density to be 3.3×10^(15)cm^(-2),close to the lowest values reported in Galactic massive star formation regions in previous studies.The corresponding O_(2)abundance upper limit is6.7×10^(-8),lower than all previous results based on SWAS observations and is close to the lowest reported value in massive star formation regions.On a galactic scale,our statistical results confirm a generally low O_(2)abundance for Galactic massive star formation regions.This abundance is also lower than results reported in extragalactic sources.

The ALMA-QUARKS Survey.Ⅰ.Survey Description and Data Reduction

This paper presents an overview of the QUARKS survey,which stands for Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures."The QUARKS survey is observing139 massive clumps covered by 156 pointings at Atacama Large Millimeter/submillimeter Array(ALMA)Band 6(λ~1.3 mm).In conjunction with data obtained from the ALMA-ATOMS survey at Band 3(λ~3 mm),QUARKS aims to carry out an unbiased statistical investigation of massive star formation process within protoclusters down to a scale of 1000 au.This overview paper describes the observations and data reduction of the QUARKS survey,and gives a first look at an exemplar source,the mini-starburst Sgr B2(M).The wide-b and width(7.5 GHz)and high-angular-resolution(~0."3)observations of the QUARKS survey allow for the resolution of much more compact cores than those could be done by the ATOMS survey,and to detect previously unrevealed fainter filamentary structures.The spectral windows cover transitions of species including CO,SO,N_(2)D^(+),SiO,H_(30)α,H_(2)CO,CH_(3)CN,and many other complex organic molecules,tracing gas components with different temperatures and spatial extents.QUARKS aims to deepen our understanding of several scientific topics of massive star formation,such as the mass transport within protoclusters by(hub-)filamentary structures,the existence of massive starless cores,the physical and chemical properties of dense cores within protoclusters,and the feedback from already formed high-mass young protostars.

HIGH-ORDER WENO SIMULATIONS OF THREE-DIMENSIONAL RESHOCKED RICHTMYER-MESHKOV INSTABILITY TO LATE TIMES:DYNAMICS,DEPENDENCE ON INITIAL CONDITIONS,AND COMPARISONS TO EXPERIMENTAL DATA

The dynamics of the reshocked multi-mode Richtmyer-Meshkov instability is investigated using 513 × 257^2 three-dimensional ninth-order weighted essentially nonoscil- latory shock-capturing simulations. A two-mode initial perturbation with superposed ran- dom noise is used to model the Mach 1.5 air/SF6 Vetter-Sturtevant shock tube experiment. The mass fraction and enstrophy isosurfaces, and density cross-sections are utilized to show the detailed flow structure before, during, and after reshock. It is shown that the mixing layer growth agrees well with the experimentally measured growth rate before and after reshock. The post-reshock growth rate is also in good agreement with the prediction of the Mikaelian model. A parametric study of the sensitivity of the layer growth to the choice of amplitudes of the short and long wavelength initial interfacial perturbation is also pre- sented. Finally, the amplification effects of reshock are quantified using the evolution of the turbulent kinetic energy and turbulent enstrophy spectra, as well as the evolution of the baroclinic enstrophy production, buoyancy production, and shear production terms in the enstrophy and turbulent kinetic transport equations.

Observation of ocean current response to 1998 Hurricane Georges in the Gulf of Mexico

The ocean current response to a hurricane on the shelf-break is examined. The study area is the DeSoto Canyon in the northeast Gulf of Mexico, and the event is the passage of 1998 Hurricane Georges with a maximum wind speed of 49 m/s. The data sets used for analysis consist of the mooring data taken by the Field Program of the DeSoto Canyon Eddy Intrusion Study, and simultaneous winds observed by NOAA （National Oceanic and Atmospheric Administration） Moored Buoy 42040. Time-depth ocean current energy density images derived from the observed data show that the ocean currents respond almost immediately to the hurricane with important differences on and offthe shelf. On the shelf, in the shallow water of 100 m, the disturbance penetrates rapidly downward to the bottom and forms two energy peaks, the major peak is located in the mixed layer and the secondary one in the lower layer. The response dissipates quickly after external forcing disappears. Offthe shelf, in the deep water, the major disturbance energy seems to be trapped in the mixed layer with a trailing oscillation; although the disturbance signals may still be observed at the depths of 500 and 1 290 m. Vertical dispersion analysis reveals that the near-initial wave packet generated offthe shelf consists of two modes. One is a barotropic wave mode characterized by a fast decay rate of velocity amplitude of 0.020 s^-, and the other is baroclinic wave mode characterized by a slow decay rate of 0.006 9 s^-1. The band-pass-filtering and empirical function techniques are employed to the frequency analysis. The results indicate that ialf frequencies shift above the local inertial frequency. On the shelf, the average frequency is 1.04fin the mixed layer, close to the diagnosed frequency of the first baroclinic mode, and the average frequency increases to 1.07fin the thermocline. Offthe shelf, all frequencies are a little smaller than the diagnosed frequency of the first mode. The average frequency decreases from 1.035fin the mixed layer to 1.02fin the thermocline, implying a trend for the shift in frequency of the oscillations towards f with the depth.

Assessment of Dynamic Downscaling of the Extreme Rainfall over East Asia Using a Regional Climate Model

This study investigates the capability of the dynamic downscaling method （DDM） in an East Asian climate study for June 1998 using the fifth-generation Pennsylvania State University-National Center for Atmospheric Research non-hydrostatic Mesoscale Model （MM5）.Sensitivity experiments show that MM5 results at upper atmospheric levels cannot match reanalyses data,but the results show consistent improvement in simulating moisture transport at low levels.The downscaling ability for precipitation is regionally dependent.During the monsoon season over the Yangtze River basin and the pre-monsoon season over North China,the DDM cannot match observed precipitation.Over Northwest China and the Tibetan Plateau （TP）,where there is high topography,the DDM shows better performance than reanalyses.Simulated monsoon evolution processes over East Asia,however,are much closer to observational data than reanalyses.The convection scheme has a substantial impact on extreme rainfall over the Yangtze River basin and the pre-monsoon over North China,but only a marginal contribution for Northwest China and the TP.Land surface parameterizations affect the locations and pattern of rainfall bands.The 10-day re-initialization in this study shows some improvement in simulated precipitation over some sub-regions but with no obvious improvement in circulation.The setting of the location of lateral boundaries （LLB） westward improves performance of the DDM.Including the entire TP in the western model domain improves the DDM performance in simulating precipitation in most sub-regions.In addition,a seasonal simulation demonstrates that the DDM can also obtain consistent results,as in the June case,even when another two months consist of no strong climate/weather events.

Comparison of ground truth location of earthquake from InSAR and from ambient seismic noise: A case study of the 1998 Zhangbei earthquake

Because ambient seismic noise provides estimated Green’s function （EGF） between two sites with high accuracy, Rayleigh wave propagation along the path connecting the two sites is well resolved. Therefore, earthquakes which are close to one seismic station can be well located with calibration extracting from EGF. We test two algorithms in locating the 1998 Zhangbei earthquake, one algorithm is waveform-based, and the other is traveltime-based. We first compute EGF between station ZHB （a station about 40 km away from the epicenter） and five IC/IRIS stations. With the waveform-based approach, we calculate 1D synthetic single-force Green’s functions between ZHB and other four stations, and obtain traveltime corrections by correlating synthetic Green’s functions with EGFs in period band of 10–30 s. Then we locate the earthquake by minimizing the differential travel times between observed earthquake waveform and the 1D synthetic earthquake waveforms computed with focal mechanism provided by Global CMT after traveltime correction from EGFs. This waveform-based approach yields a location which error is about 13 km away from the location observed with InSAR. With the traveltime-based approach, we begin with measuring group velocity from EGFs as well as group arrival time on observed earthquake waveforms, and then locate the earthquake by minimizing the difference between observed group arrival time and arrival time measured on EGFs. This traveltime-based approach yields accuracy of 3 km, Therefore it is feasible to achieve GT5 （ground truth location with accuracy 5 km） with ambient seismic noises. The less accuracy of the waveform-based approach was mainly caused by uncertainty of focal mechanism.

Seismotectonics of the 2008 and 2009 Qaidam Earthquakes and its Implication for Regional Tectonics

Three magnitude 〉6 earthquakes struck Qaidam, Qinghai province, China, in November 10th 2008, August 28th and 31st 2009 respectively. The Zongwulongshan fault has often been designated as the active seismogenic structure, although it is at odd with the data. Our continuous GPS station （CGPS）, the Xiao Qaidam station, located in the north of the Qaidam basin, is less than 30 km to the southwest of the 2008 earthquake. This CGPS station recorded the near field co-seismic deformation. Here we analyzed the co-seismic dislocation based on the GPS time series and the rupture processes from focal mechanism for the three earthquakes. The afiershocks were relocated to constrain the spatial characteristics of the 2008 and 2009 Qaidam earthquakes. Field geological and geomorphological investigation and interpretation of satellite images show that the Xitieshan fault and Zongwulongshan fault were activated as left lateral thrust during the late Quaternary. Evidence of folding can also be identified. Integrated analyses based on our data and the regional tectonic environment show that the Xitieshan fault is the fault responsible for the 2008 Qaidam earthquake, which is a low dip angle thrust with left lateral strike slip. The Zongwulongshan fault is the seismogenic fault of the 2009 earthquakes, which is a south dipping back thrust of the northern marginal thrust system of the Qaidam basin. Folding takes a significant part of the deformation in the northern marginal thrust system of the Qaidam basin, dominating the contemporary structure style of the northern margin of the Qaidam basin and Qilianshan tectonic system. In this region, this fault and fold system dominates the earthquake activities with frequent small magnitude earthquakes.

A study on the uncertainties of the centroid depth of the 2013 Lushan earthquake from teleseimic body wave data

Centroid depth of earthquakes is essential for seismic hazard mitigation. But, various studies provided different solutions for the centroid depth of the damaging 2013 Lushan earthquake, thus hindering further studies of the earthquake processes. To resolve its centroid depth and assess the uncertainties, we apply the teleseismic cut and paste method to invert for centroid depth with teleseismic body waves in the epicentral distance of 300-90~. We performed the inversion for P waves only as well the case of both P and SH waves and found that both cases lead to depth solutions with difference less than 0.5 km. We also investigated the effects on depth inversion from azimuth gap of seismic stations, source duration, and comer fre- quency of filter. These various tests show that even azi- muthal distribution of seismic stations is helpful for accurate depth inversion. It is also found that estimate of centroid depth is sensitive to source duration. Moreover, the depth is biased to larger values when corner frequency of low-pass filter is very low. The uncertainty in the velocity model can also generate some error in the depth estimation （- 1.0 km）.With all the above factors consid- ered, the centroid depth of Lushan earthquake is proposed to be around 12 km, with uncertainty about 2 km.

On generation source sites of internal waves in the Luzon Strait

This effort aims to determine the generation source sites in the Luzon Strait for energetic, long-crest, transbasin internal waves （IW） observed in the northern South China Sea （NSCS）. The roles of islands distributed on eastern side of the strait, Kuroshio, submarine ridges, shoaling thennocline, and strait configuration played in the IW generation are examined using the cruise data analysis, satellite data interpretation, and dynamical analysis. The islands and channels on eastern side of the strait are excluded from a list of possible IW source sites owing to their unmatched horizontal dimensions to the scale of IW crest line length, and the relative low Reynolds number. The Kuroshio has a potential to be a radiator for the long-crest IW disturbances, meanwhile, the Kurosbio west （east） wing absorbs the eastward （westward） propagating IW disturbance. Namely, the Kuroshio blockades the outside west-east propagating IW disturbances. The 3-D configuration of the Luzon Strait is characterized by a sudden, more than one order widening of the cross-section areas at the outlets on both sides, providing a favorable condition for IW type initial disturbance formation. In the Luzon Strait, the thermocline is featured by a westward shoaling all the year around, providing the dynamical conditions for the amplitude growth （declination） to the westward （eastward） propagating IW type disturbance. Thus, the west slope of western submarine ridge at the western outlet of the Luzon Strait is a high possibility source sites for energetic, long-crest, transbasin IWs in the NSCS. The interpretation results of satellite SAR images during a 13 a period from 1995 to 2007 provide the convincing evidence for the conclusions.

Analysis of the genetic interactions between Cyclin A1, Atm and p53 during spermatogenesis

Aim： To analyze the functional interactions of Cyclin with p53 and Atm in spermatogenesis and DNA double- strand break repair. Methods： Two lines of double knockout mice were generated. Spermatogenesis and double strand break repair mechanisms were analyzed in Cyclin A1 （Ccnal）; p53- and Ccnal; Atm-double knockout mice. Results： The block in spermatogenesis observed in Cyclin A1-/- （Ccnal-/-） testes at the mid-diplotene stage is associated with polynucleated giant cells. We found that Ccnal-deficient testes and especially the giant cells accumulate unrepaired DNA double-strand breaks, as detected by immunohistochemistry for phosphorylated H2AX. In addition, the giant cells escape from apoptosis. The development of giant cells occurred in meiotic prophase I, because testes lacking ATM, which are known to develop spermatogenic arrest earlier than prophase I, do not develop giant cells in the absence of cyclin A1. Cyclin A1 interacted with p53 and phosphorylated p53 in complex with CDK2. Interestingly, p53-deficiency significantly increased the number of giant cells in Ccnal-deficient testes. Gene expression analyses of a panel of DNA repair genes in the mutant testes revealed that none of the genes examined were consistently misregulated in the absence of cyclin A1. Conclusion： Ccnal-deficiency in spermatogenesis is associated with defects in DNA double-strand break repair, which is enhanced by loss of p53.

Dynamical analysis of mesoscale eddy-induced ocean internal waves using linear theories

This study aims to explore generation mechanisms of the ocean internal wave using the dynamical analysis methods based on linear theories. Historical cruise measurements and recent synthetic aperture radar （SAR） observations of mesoscale eddies with diameter of several tens of kilometers to hundreds of kilometers show that the internal wave packets with wavelength of hundreds of meters to kilometer exist inside the mesoscale eddies. This coexistence phenomenon and inherent links between the two different scale processes are revealed in the solutions of governing equations and boundary conditions for the internal wave disturbance with a horizontally slowly variable amplitude in a cylindrical coordinate system. The theoretical solutions indicate that the instability of eddy current field provides the dynamical mechanism to internal wave generation. The derived dispersion relation indicates that the internal wave propagation is modified by the eddy current field structure. The energy equation of the internal waves clearly shows the internal wave energy increment comes from the eddy. The theoretical models are used to explain the observation of the mesoscale eddy-induced internal waves off the Norwegian coast. The two-dimensional waveform solution of the anticyclonic eddy-induced internal wave packet appears as ring-shaped curves, which contains the typical features of eddy stream lines. The comparison of theoretical solutions to the structure of the internal wave packets on SAR image shows a good agreement on the major features.

Recent advances in design and applications of biomimetic self-assembled peptide hydrogels for hard tissue regeneration

The development of natural biomaterials applied for hard tissue repair and regeneration is of great importance,especially in societies with a large elderly population.Self-assembled peptide hydrogels are a new generation of biomaterials that provide excellent biocompatibility,tunable mechanical stability,injectability,trigger capability,lack of immunogenic reactions,and the ability to load cells and active pharmaceutical agents for tissue regeneration.Peptide-based hydrogels are ideal templates for the deposition of hydroxyapatite crystals,which can mimic the extracellular matrix.Thus,peptide-based hydrogels enhance hard tissue repair and regeneration compared to conventional methods.This review presents three major self-assembled peptide hydrogels with potential application for bone and dental tissue regeneration,including ionic self-complementary peptides,amphiphilic(surfactant-like)peptides,and triple-helix(collagen-like)peptides.Special attention is given to the main bioactive peptides,the role and importance of self-assembled peptide hydrogels,and a brief overview on molecular simulation of self-assembled peptide hydrogels applied for bone and dental tissue engineering and regeneration.