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.

Abundance and biomass of meiobenthos in the spawning ground of anchovy (Engraulis japanicus) in the southern Huanghai Sea

A grid of 22 stations, giving a broad coverage of the spawning ground of anchovy in the southern Huanghai Sea was selected. Undis- turbed sediments were taken from sampling stations during the cruise in June 2003. The average abundance of meiofauna is (1 584± 686) ind./10cm2, with corresponding biomass (dwt) of (1 086±425)!μg/10cm2. The pattern of abundance of meiofauna is similar to the pattern of biomass. There are 65.88% meiofauna in 0￣2 cm sediments, 27.66% in 2￣5 cm sediments and 6.47% in 5￣8 cm sediments. The Spearman correlation analysis between meiofauna and environmental factors shows that abundance of meiofauna, free living ma- rine nematodes, benthic copepods has significant positive correlations with Chl-a. And the abundance of copepods has significant posi- tive correlations with several factors such as Chl-a, Pha-a, Chl-a plus Pha-a and organic matter. A total of 18 meiofauna groups are i- dentified. Nematode is the most dominant group, average abundance (1 404±670) ind/10cm2, accounting for 88.65%, and the follow- ing groups are also important: benthic copepods (5.48%), kinorhyncha (1.26%), polychaeta (1.07%). By biomass, dominant groups are nematodes (51.72%), polychaeta (21.84%), copepods (14.87%), ostracoda (4.92%), kinorhyncha (3.67%). A total of 90 species of ne- matodes are identified. The species composition of nematodes is listed based on selected two stations 7794 (coastal area) and 10694 (cold water mass in deep waters).

Abundance and biomass of heterotrophic microbes in the Kongsfjorden, Svalbard

Abundance and biomass of heterotrophic microbes were investigated usingepifluorescense microscopy in August 2004 along a transect in the Kongsfjorden, a glacial fjord inthe high arctic, located in the north-western part of Svalbard. A bacterial abundance was low atouter fjord stations (on average 2.29 x 10~8 ind./dm^3) and was higher at inner fjord stations (onaverage 3.52 x 10~8 ind./dm^3).The biomass of bacteria ranged from 3.69 to 8.01 mg/m^3.The abundanceof bacteria was low at the surface of water(0 m), whereas the higher abundances often occurred atdepths of 30～50 m.The abundance of heterotrophic flagellates varied from 2.785 to 8.891 x 10~4 ind./dm^3. The assemblage was numerically dominated by less than 5 μm heterotrophic flagellates(78.67%～94.80%).The biomass of heterotrophic flagellates varied from 0.37 to 2.30 mg/m^3.The meanbiomass distribution for all stations was 4.91% for less than 5 μm heterotrophic flagellates,86.74% for 6～20 μm flagellates and 8.35% for greater than 20 μm sized flagellates.The low biomassof heterotrophic flagellates often occurred at the surface of water (0 m),while the maximum valueof biomass occurred at different depths. The biomass of total heterotrophic microbial communityranged from 4.20 to 10.03 mg/m^3.The mean biomass distribution for all stations was 82.58% forbacteria, 15.77% for flagellates and 1.66% for ciliates.

The biogeographical distribution of tree species-abundance and its relation to climatic factors in mass islands

Tree species-abundance in forests is a function of geographical area and climate, although it is not clear whether such relationships apply to mass islands. We examined the spatial pattern of tree species in mass islands along the coast of Zhejiang, East China Sea using the Preston model, to identify the relationships between tree communities and climatic conditions. The results show that：（1） the biogeographical distribution of tree species-abundance conformes to Preston＇s log-normal pattern, and is in accordance with the findings in both tropical rainforests and estuarine forests;（2） the climatic factors related to tree communities in mass islands are similar to that of the subtropical zone, including the major species of evergreen needle-leaf, broad-leaf and deciduous broad-leaf forests. We conclude that the Preston model can be applied to the trees of mass islands and thus facilitate the systematic ecological researches of vegetation species＇ composition in subtropical zone.

Community structure of picoplankton abundance and biomass in the southern Huanghai Sea during the spring and autumn of 2006

During spring and autumn of 2006, the investigations on abundance, carbon biomass and distri- bution of picoplankton were carried out in the southern Huanghai Sea （Yellow Sea, sHS）. Three groups of picoplankton-Synechococcus （Syn）, Picoeukaryotes （PEuk） and heterotrophic bacteria （BAC） were identified, but Prochlorococcus （Pro） was undetected. The average abundance of Syn and PEuk was lower in spring （5.0 and 1.3×10^3 cells/cm^3, respectively） than in autumn （92.4 and 2.7×0^3 cells/cm^3, respectively）, but it was opposite for BAC （1.3 and 0.7×10^6 cells/cm^3 in spring and autumn, respectively）. And the total carbon biomass of picoplankton was higher in spring （37.23×11.67） mg/m^3 than in autumn （21.29×13.75） mg/m^3. The ratios of the three cell abundance were 5：1：1 341 and 30：1：124 in spring and autumn, respectively. And the ratios of carbon biomass of them were 5：7：362 and 9：4：4 in spring and autumn, respectively. Seasonal distribution characteristics of Syn, PEuk, BAC were quite different from each other. In spring, Syn abundance decreased in turn in the central waters （where phytoplankton bloom in spring occurred）, the southern waters and inshore waters of the Shandong Peninsula （where even Syn was undetected）; the high values of PEuk abundance appeared in the central and southern waters and the inshore of the Shandong Peninsula; the abundance of BAC was nearly three order of magnitude higher than that of photosynthetic picoplankton, and high values appeared in the central waters. In autumn, Syn abundance in central waters was higher than that in surrounding waters, while for PEuk abundance, it decreased in turn in the inshore waters of the Shandong Peninsula, the southern waters and the central waters; BAC presented a complicated blocky type distribution. Sub-surface maximum of each group of picopalnkton appeared in both spring and autumn. Compared with the available lit- eratures concerning the studied area, the range of Syn abundance was larger, and the abundance of BAC was higher. In addition, the conversion factors for calculating picoplanktonic carbon biomass were discussed, with the conversion factors which are different from previous studies in the same surveyed waters. The result of regression analysis showed that there was distinct positive correlation between BAC and photosynthetic picoplankton in spring （r=0.61, P 〈0.001）, but no correlation was found in autumn.

Afforestation effects on soil microbial abundance, microbial biomass carbon and enzyme activity in dunes of Horqin Sandy Land, northeastern China

In order to investigate the effects of afforestation on soil microbial abundance, microbial biomass carbon and enzyme activity in sandy dunes, 20-year-old Pinus sylvestris var. mongolica Litv. （PSM） and Populus simonii Carri6re （PSC） mature forests were se- lected in Horqin Sandy Land, and mobile dunes was set as a control （CK）. Results show that PSM and PSC plantations can im- prove soil physicochemical properties and significantly increase microbiological activity in mobile dunes. Soil microbial abun- dance, microbial biomass carbon and enzyme activity show an order of PS〉PSM〉CK. Total soil microbial abundance in PSM and PSC was respectively 50.16 and 72.48 times more than that in CK, and the differences were significant among PSM, PSC and CK Soil microbial biomass carbon in PSM and PSC was respectively 23.67 and 33.34 times more than that in CK, and the difference was insignificant between PSM and PSC. Soil enzyme activity, including dehydrogenase （DEH）, peroxidase （PER）, protease （PRO）, urease （URE） and cellobiohydrolase （CEL） in PSM and PSC were respectively 19.00 and 27.54, 4.78 and 9.89, 4.05 and 8.67, 29.93 and 37.46, and 9.66 and 13.42 times of that in CK. R sylvestris and P. simonii can effectively improve soil physico- chemical and microbiological properties in sandy dunes and fix mobile dunes in Horqin Sandy Land. The Cmic：C ratio is an appli- cable indicator to estimate soil stability and soil water availability, and based on an overall consideration of plantation stability and sustainability, R sylvestris is better than R simonii in fixing mobile dunes in sandy land.

Abundance and Biomass of Benthic Heterotrophic Bacteria in Jiaozhou Bay, China

The abundance and biomass of benthic heterotrophic bacteria were investigated for the 4 typical sampling stations in the northern muddy part of Jiaozhou Bay, estuary of the Dagu River, raft culturing and nearby areas of Huangdao in March, June, August and December, 2002. The abundance and biomass range from 0.98×107 to 16.87×107cells g-1 sediment and 0.45 to 7.08μgCg-1 sediment, respectively. Correlation analysis showed that heterotrophic bacterial abundance and biomass are significantly correlated to water temperature (R =0.79 and 0.83, respectively, P<0.01).

Temporal variations of mesozooplankton abundance and biomass in the mangrove creek area along the Karachi coast, Pakistan

The temporal variations of mesozooplankton abundance and biomass （1-Volumetric method by settling volume and displacement volume and 2- Gravimetric method through wet weight, dry weight and ash-free dry weight） with relation to environmental parameters were studied in the mangrove creek area of Karachi coast, Pakistan. The data of mesozooplankton samples along with environmental parameters （temperature, salinity, pH, etc.） were collected during January 1998 to December 1998 from two creek stations. The abun-dance of mesozooplankton also exhibited seasonal trends at both stations. At Sta. S2, the highest and low-est abundance values were observed during post-monsoon and southwest monsoon respectively whereas, at Sta. S1, a clear trend of high abundance in pre-monsoon to low abundance in southwest monsoon was observed. Mesozooplankton abundance was also positively correlated with settling volume, displacement volume, wet weight and dry weight. The highest biomass value was observed in the northeast monsoon and pre-monsoon periods. The results of the canonical analysis of the output from the discriminate function was tested. Out of fifteen variables, only one was significantly different in single character ratios dry weight/ash free-dry weight （F3,23=4.78,P＆lt;0.005）. The mesozooplankton community was collectively composed of 28 taxa. Among these groups, copepoda （66.3%）, gastropod larvae （9.94%）, evadne （4.60%）, zoea （3.60%）, cypris nauplii （2.56%）, lemellibranch larvae （1.87%）, chaetognaths （1.81%）, ostracods （1.73%）, lucifer （1.15%） and barnacles nauplii （1.35%） contributed the most to the similarities within Sta. S1, while copepoda （74.68%）, cypris nauplii （5.29%）, gastropods （4.87%）, barnacles nauplii （4.81%）, evadne （1.72%）, zoea （1.53%） and ca-ridean larvae （1.18%） at Sta. S2. The remaining mesozooplanktonic group were accounted for less than 5% and 6% at Sta. S1 and Sta. S2 respectively, of the total organisms. Similarity percentage （SIMPER） analysis revealed that copepoda, gastropod larvae and cyprus nauplii contributed most of the similarities within Sta. S2 along Sta. S1.

p-capture reaction cycles in rotating massive stars and their impact on elemental abundances in globular cluster stars: A case study of O, Na and Al

Elemental abundance patterns of globular cluster stars can provide important clues for understanding cluster formation and early chemical evolution.The origin of the abundance patterns,however,still remains poorly understood.We have studied the impact of p-capture reaction cycles on the abundances of oxygen,sodium and aluminium considering nuclear reaction cycles of carbon-nitrogenoxygen-fluorine,neon-sodium and magnesium-aluminium in massive stars in stellar conditions of temperature range 2×107to 10×107K and typical density of 102gm cc-1.We have estimated abundances of oxygen,sodium and aluminium with respect to Fe,which are then assumed to be ejected from those stars because of rotation reaching a critical limit.These ejected abundances of elements are then compared with their counterparts that have been observed in some metal-poor evolved stars,mainly giants and red giants,of globular clusters M3,M4,M13 and NGC 6752.We observe an excellent agreement with[O/Fe]between the estimated and observed abundance values for globular clusters M3 and M4 with a correlation coefficient above 0.9 and a strong linear correlation for the remaining two clusters with a correlation coefficient above 0.7.The estimated[Na/Fe]is found to have a correlation coefficient above 0.7,thus implying a strong correlation for all four globular clusters.As far as[Al/Fe]is concerned,it also shows a strong correlation between the estimated abundance and the observed abundance for globular clusters M13 and NGC 6752,since here also the correlation coefficient is above 0.7 whereas for globular cluster M4 there is a moderate correlation found with a correlation coefficient above 0.6.Possible sources of these discrepancies are discussed.

Community composition, abundance and biomass of zooplankton in Zhangzi Island waters, Northern Yellow Sea

Samples were collected monthly from the sea area around Zhangzi Island,northern Yellow Sea,from July 2009 to June 2010.Vertical net towing was used to examine spatial and temporal variability in zooplankton abundance and biomass.Overall,C alanus sinicus and Saggita crassa were the dominant species found during the study period,while the amphipod T hemisto gracilipes was dominant in winter and spring.Vast numbers of the ctenophore species of the genus Beroe were found in October and November.It was not possible to count them,but they constituted a large portion of the total zooplankton biomass.Zooplankton species diversity was highest in October,and species evenness was highest in April.Zooplankton abundance(non-jellyfi sh)and biomass were highest in June and lowest in August,with annual averages of 131.3 ind./m3and 217.5 mg/m3,respectively.Water temperature may be responsible for the variations in zooplankton abundance and biomass.B eroe biomass was negatively correlated with other zooplankton abundance.Longterm investigations will be carried out to learn more about the infl uence of the environment on zooplankton assemblages.

Standard Model Fermion Masses and Charges from Holographic Analysis

The Standard Model of particle physics involves twelve fundamental fermions, treated as point particles, in four charge states. However, the Standard Model does not explain why only three fermions are in each charge state or account for neutrino mass. This holographic analysis treats charged Standard Model fermions as spheres with mass 0.187 g/cm2 times their surface area, using the proportionality constant in the holographic relation between mass of the observable universe and event horizon radius. The analysis requires three Standard Model fermions per charge state and relates up quark and down quark masses to electron mass. Holographic analysis specifies electron mass, to six significant figures, in terms of fundamental constants α,ℏ,G,Λ and Ω Λ . Treating neutrinos as spheres and equating electron neutrino energy density with cosmic vacuum energy density predicts neutrino masses consistent with experiment.

Annual variation in Calanus sinicus abundance and population structure in the northern boundary area of the Yellow Sea Cold Water Mass

The Yellow Sea Cold Water Mass （YSCWM） was suggested as an over-summering site of the dominant copepod species Calanus sinicus in coastal Chinese seas. Population abundance and structure were investigated by monthly sampling along three transects across the northern boundary of the YSCWM during 2009-2010. Results show that thermal stratification existed from June to October and that the vertical thermal difference increased with depth. Generally, total abundance was lowest in October and highest in June, and the female/male sex ratio was highest in February and lowest in August. Evident spatial differences in abundance were observed during the existence of the YSCWM. In June, total abundance averaged 158.8 ind/m~ at well-stratified stations, and 532.1 ind/m3 at other stations. Similarly, high abundances of 322.0 and 324.4 ind/m3 were recorded from July to August inside the YSCWM, while the abundance decreased from 50.4 to 1.9 ind/m3 outside the water mass. C. sinicus distribution tended to even out over the study area in September when the YSCWM disappeared. We believe that the YSCWM may retard population recruitment in spring and preserve abundant cohorts in summer. The summer population was transported to neritic waters in autumn. In addition to low temperatures, stable vertical structure was also an essential condition for preservation of the summer population. C. sinicus can survive the summer in marginal areas in high abundance, but the population structure is completely different in terms of C5 proportion and sex ratio.

Short-Term Influence of Burning on Species Abundance, Biomass Production, Wood Plant Density and Browsing Unit in an Albany Thicket of the Eastern Cape, South Africa

Fire is regarded as management practice for maintaining grasslands and savannas. The vegetation occurring in fire prone areas becomes highly adapted to fire occurrences in savannas and grasslands. However, documentation on the influence of burning on vegetation is still limited in an albany thicket biome. The aim of the study was to evaluate the short-term influence of burning on species abundance, biomass production, wood plant density and browsing unit. Six plots (2500 m2) were demarcated;in each plot two parallel transects of 120 m2 with 5 m distance apart were measured. Three plots were burned in spring season, while no burning was done on the other remaining plots. Forty points per plot were obtained using step-point method to determine the relative abundance at burned and unburned plots. Woody plants occurred within a transect were identified, counted and recorded to determine density and browsing unit. Three quadrats (i.e. 0.25 m2) per plot were randomly laid within the transect;aboveground plant material within a quadrat were harvested. A total of 18 samples were harvested and oven dried at 60˚C for 48 hours to determine biomass production. The results showed that Themeda triandra (14%) and Panicum maximum (10%) were most abundant grass species at the burned plots. Burned plots had significantly higher biomass production (4804 kg/ha) compared to unburned plots (3641 kg/ha). Vachellia karoo (burned: 65.85% & unburn: 13.70%) and Searsia pallens (burned: 26.83% & unburned: 6.85%) were most dominant wood plant species at both burned and unburned plots. Burned plots had the highest browsing unit (3221 BU/ha) compared to unburned plots (2058 BU/ha). The decrease of woody plants at the burned plots proved that fire has a tremendous potential for managing woody plants. This study provided information on short-term influence of burning, however further long-term trials are required to determine the effects of burning.

Effect of Sample Matrix on Radial and Axial Profiles of Ion Abundance in Inductively Coupled Plasma Mass Spectrometry

In inductively coupled plasma mass spectrometry (ICP-MS) analysis, only a few options are available to deal with non-spectroscopic interferences. Considering that diluting the sample is impractical for traces analysis, other alternatives must be employed. Traditionally, the method of standard additions is used to correct the matrix effect but it is a time consuming method. Others methods involves separation techniques. Another way to overcome matrix interferences is to understand the mechanism involved and adjust plasma viewing conditions to reduce or eliminate the effect. In this study, the effect of various concomitant elements in ICP-MS was assessed by measuring the distribution of selected singly charged analyte ions (Al, V, Cr, Mn, Ni, Co, Cu, Zn, As, In, Ba, La, Ce, Pb), doubly charged ions (La, Ce, Ba and Pb) and oxides ions (BaO) in the presence of concomitant elements spanning a mass range from 23 (Na) to 133 (Cs) u.m.a. and different ionization energies. Concomitant elements are alkali metals, alkaline earth metals and Si. Analyte ion suppression was observed while moving the ICP across and away from the sampling interface with or without a single concomitant element. Matrix effect measures were realised, firstly, to highlight the relation between the signal extinction of an analyte and the masse of the concomitant element, and secondly to highlight the relation between the removal of the analyte signal and the first ionization energy of the element of matrix. A dependence upon both the mass of the matrix element and the mass of the analyte was observed. The suppression seems increased with increasing matrix element mass and decreased with increasing analyte mass. The effect of the mass of the matrix element was the more significant of the two factors. If space-charge effects were found to be significant for matrix elements of much lower mass, it seems diffusion also played an active part for heavier matrix elements. Finally, some evidence was found for a shift in ion-atom equilibrium for dications and for energy demand regarding oxides.

Estimation of ages and masses via carbon and nitrogen abundances for 556 007 giants from LAMOST

Estimating ages for a large number of giants is of great importance for studying Galactic evolution.In this work,we determine stellar ages and masses for 556007 giants from LAMOST Data Release 5(DR5)with empirical relations estimated from chemical[C/N]abundance ratios.Our sample reveals the two wellknown sequences in the age-[α/M]relation.The high-αsequence is composed of stars older than 8 Gyr and low-αsequence is composed of stars with age ranging from 0 Gyr to 13.8 Gyr.Our sample also shows a flat age-[M/H]relation up until 12 Gyr.We compare these distributions with Galactic Chemical Evolution models for reference.When looking at the spatial distribution of stars in 2 Gyr age bins,we find that young stars are concentrated towards the Galactic plane and older stars extend to higher height above and below the disk.We find a smooth transition of median Galactic height for different age bins,which suggests a strong age-dependence on Galactic scale height.

Muscle Mass Is Associated with Depression in Adolescents and Young Adults

Background and Aims: The study aims to explore the association between body composition and depression in adolescents and young adults. Methods: A random cluster sampling method was used to select 41 age-matched indi-viduals (aged 11 - 30) as a non-depressive control group. The Department of Psychology at the Affiliated Hospital of Youjiang Medical University for Na-tionalities recruited 27 depressive patients within the same age range. Bioelec-trical impedance analysis measured body composition, while SCL-90, SAS, and SDS were employed for depression diagnosis. Logistic regression analysis was conducted to assess the relationship between body composition and de-pression scores. Results: The Depression Group exhibited higher levels of fat mass (p Conclusion: Depression is associated with age, gender, and muscle mass in adolescents and young people. Proper exercise and a healthy diet can increase muscle mass, thereby reducing fat mass and, as a result, reducing the prevalence of depression.

Psychological Consequences of a Mass Attack Following Multiple Gunshots and Explosions among Victims in a State in Southwest Nigeria

Introduction: On the 5th of June 2022, an incident of a mass attack following multiple gunshots and explosions occurred in a community in Ondo State Nigeria. This study aims to assess the mental health status of victims of the mass attack to guide further interventions among them. Methods: A cross-sectional study was conducted among victims of a mass attack in Owo community, Ondo State. A total of 209 affected victims were interviewed on socio-demographic characteristics, symptoms of anxiety (AD) and post-traumatic stress disorder (PTSD), threat experienced, and mental health support received. A 7-item Generalized Anxiety Disorder (GAD-7) and 9-item Post Traumatic Stress Disorder (PTSD) scale were used to assess the mental health status of the victims. A point was assigned to respondents who reported the symptoms of GAD, with a maximum score of 7 attained. For GAD, scores were categorized as follows: 1 - 2 as mild, 2 - 3 as minimal, 4 - 5 as moderate and 6 - 7 as severe. The PTSD symptoms were rated using a 5-point Likert scale response, and assigned the following points;4 = extremely, 3 = quite a bit, 2 = moderate, 1 = a little bit and 0 = not at all. From a maximum score of 36, participants with scores 18 and above were categorized as those with provisional PTSD. The independent samples t-test and correlational analysis were used to determine the association between PTSD score and other independent variables, with an alpha level of significance set at 0.05. Results: Generally, 38 (18.2%) of the respondents had severe AD. About half (89;42.6%) were categorized as those with provisional PTSD. The mean level of both AD (3.40 ± 2.26) and PTSD (16.51 ± 7.63) score is higher among those who were married compared to those not married (anxiety disorder;2.52 ± 2.20, P = 0.005 and PTSD;13.20 ± 8.86, P = 0.004). Respondents who have been counseled by a healthcare worker had a higher mean level (15.89 ± 7.58) of provisional PTSD compared to those not counseled by a healthcare worker (13.56 ± 9.22, P = 0.046). The level of PTSD score increased with a higher age group (r = 0.21, P = 0.003). Conclusions: The results show that the mass attack had psychological consequences among a high proportion of the victims, particularly, those married and in the older age groups. This suggests the need for continuous supportive counseling targeting these affected groups, and considering other factors moderating the effectiveness of counseling among them in future interventions.

The Energy Origin of Mass

The concept of mass manifests in diverse forms, dimensions and configurations, and yet among all these manifestations, a unified origin is usually yearned for. This study aims to propose models that attribute the emergence of mass from fundamental quantities of physics, notably energy, space, and time. To this end, an operator is introduced, wherein these fundamental concepts serve as inputs, yielding functions that characterise mass. These functions are grounded in the domain of complex numbers, augmented by the incorporation of probabilistic elements, facilitating a nuanced depiction of mass modulation. Through investigation, it becomes apparent that a corollary energy field arises surrounding mass, facilitating its interactions within its surroundings. Ultimately, the comprehensive model of mass, inclusive of its associated field, gives rise to interactions with other masses, thereby engendering the genesis of larger and denser manifestations of mass, a phenomenon expounded within this framework.

Tricuspid mass-curious case of Li-Fraumeni syndrome: A case report

BACKGROUND Li-Fraumeni syndrome(LFS)is a rare autosomal dominant cancer-predisposing syndrome,which can manifest as a polymorphic spectrum of malignancies.LFS is associated with an early onset in life,with the majority of cases occurring prior to the age of 46.Notwithstanding the infrequency of primary cardiac tumors,it behooves clinicians to remain vigilant in considering the differential diagnosis of such tumors in LFS patients who present with a cardiac mass.This is due to the markedly elevated risk for malignancy in this particular population,far surpassing that of the general populace.CASE SUMMARY Herein,we present a case of a 30-year-old female with LFS who was found to have a tricuspid valve leaflet mass.CONCLUSION This case exemplifies valuable learning points in the diagnostic approach for this exceptionally rare patient population.

Probabilistic analysis of tunnel face seismic stability in layered rock masses using Polynomial Chaos Kriging metamodel

Face stability is an essential issue in tunnel design and construction.Layered rock masses are typical and ubiquitous;uncertainties in rock properties always exist.In view of this,a comprehensive method,which combines the Upper bound Limit analysis of Tunnel face stability,the Polynomial Chaos Kriging,the Monte-Carlo Simulation and Analysis of Covariance method(ULT-PCK-MA),is proposed to investigate the seismic stability of tunnel faces.A two-dimensional analytical model of ULT is developed to evaluate the virtual support force based on the upper bound limit analysis.An efficient probabilistic analysis method PCK-MA based on the adaptive Polynomial Chaos Kriging metamodel is then implemented to investigate the parameter uncertainty effects.Ten input parameters,including geological strength indices,uniaxial compressive strengths and constants for three rock formations,and the horizontal seismic coefficients,are treated as random variables.The effects of these parameter uncertainties on the failure probability and sensitivity indices are discussed.In addition,the effects of weak layer position,the middle layer thickness and quality,the tunnel diameter,the parameters correlation,and the seismic loadings are investigated,respectively.The results show that the layer distributions significantly influence the tunnel face probabilistic stability,particularly when the weak rock is present in the bottom layer.The efficiency of the proposed ULT-PCK-MA is validated,which is expected to facilitate the engineering design and construction.