An improved four-dimensional variation source term inversion model with observation error regularization

Aiming at the Four-Dimensional Variation source term inversion algorithm proposed earlier,the observation error regularization factor is introduced to improve the prediction accuracy of the diffusion model,and an improved Four-Dimensional Variation source term inversion algorithm with observation error regularization(OER-4DVAR STI model)is formed.Firstly,by constructing the inversion process and basic model of OER-4DVAR STI model,its basic principle and logical structure are studied.Secondly,the observation error regularization factor estimation method based on Bayesian optimization is proposed,and the error factor is separated and optimized by two parameters:error statistical time and deviation degree.Finally,the scientific,feasible and advanced nature of the OER-4DVAR STI model are verified by numerical simulation and tracer test data.The experimental results show that OER-4DVAR STI model can better reverse calculate the hazard source term information under the conditions of high atmospheric stability and flat underlying surface.Compared with the previous inversion algorithm,the source intensity estimation accuracy of OER-4DVAR STI model is improved by about 46.97%,and the source location estimation accuracy is improved by about 26.72%.

Analysis of formation and slope stability in Caofeidian Channel in Bohai Bay

In this paper, by studying bathymetric survey and shallow seismic detection data over multiple periods of history, the authors outline the geomorphic features of the Caofeidian Channel. The results of our studies indicate that the channel at the front end is dominated by erosion. The maximum water depth reaches 42.2 m, which sets the highest record for the water depth in Bohai Bay;the authors preliminarily conclude that the formation of the early channel occurred because the subsidence rate of the deep structure is slightly smaller than the deposition rate of the upper strata, and the Caofeidian Channel has existed for a long time, over 20 ka. The trending of the channel experienced a transition from the NS to the NE and then NW direction;the authors conclude that endogenic and exogenic processes, such as geological structures, the evolution of the ancient Luanhe River Delta, marine hydrodynamics, and human activity, jointly control the development and evolution of the geographic system in the Caofeidian sea area. The slope stabilities under the extreme conditions of a heavy storm and an earthquake are analyzed by performing simulations.

Adult onset type 2 familial hemophagocytic lymphohistiocytosis with PRF1 c.65delC/c.163C>T compound heterozygous mutations: A case report

BACKGROUND Familial hemophagocytic lymphohistiocytosis(FHL)is a primary immunodeficiency disease caused by gene defects.The onset of FHL in adolescents and adults may lead clinicians to ignore or even misdiagnose the disease.To the best of our knowledge,this is the first report to detail the clinical features of type 2 FHL(FHL2)with compound heterozygous perforin(PRF1)defects involving the c.163C>T mutation,in addition to correlation analysis and a literature review.CASE SUMMARY We report a case of a 27-year-old male patient with FHL2,who was admitted with a persistent fever and pancytopenia.Through next-generation sequencing technology of hemophagocytic lymphohistiocytosis(HLH)-related genes,we found compound heterozygous mutations of PRF1:c.65delC(p.Pro22Argfs*29)(frameshift mutation,paternal)and c.163C>T(p.Arg55Cys)(missense mutation,maternal).Although he did not receive hematopoietic stem cell transplantation,the patient achieved complete remission after receiving HLH-2004 treatment protocol.To date,the patient has stopped taking drugs for 15 mo,is in a stable condition,and is under follow-up observation.CONCLUSION The delayed onset of FHL2 may be related to the PRF1 mutation type,pathogenic variation pattern,triggering factors,and the temperature sensitivity of some PRF1 mutations.For individual,the detailed reason for the delay in the onset of FHL warrants further investigation.

Selective amination of the mucohalic acid derivatives

An efficient synthesis of 4,5-diamino-3-halofuran-2（5H）-ones has been developed based on a sequential acylation and bisamination of mucohalic acids. The /5- and y-amination products have also been prepared with high regioselectivity. This reaction shows some advantages in terms of its simple operation and readily available but highly functionalized starting material. All products gave satisfactory IR. 1H NMR. 13C NMR and HRMS.

Transalkylation of N-methyl tertiary amines with 3,4-dibromobutenolides

The selective transalkylation of N-methyl tertiary amines with 3,4-dibromobutenolides is described. The N-methyl group of the parent tertiary amines was replaced by alkenyl units of the butenolides; and a series of butenolide-containing tertiary enamines were obtained in moderate to good yields. Interestingly, the product 2b has shown a promising anticancer activity against HeLa cell lines （IC50 = 0.19μmol/L）.