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Accurate daily streamflow forecasting is crucial for effective flood control and water management. Decomposition ensemble models have proven to be effective in daily streamflow forecasting. However, it is important to recognize that the performance of streamflow forecasting within the decomposition ensemble models is significantly influenced by the choice of forecast model used. Therefore, a thoughtful selection of streamflow forecast models can greatly enhance the performance of decomposition ensemble models. Nevertheless, simple forecast models, such as long short-term memory, are susceptible to gradient disappearance or explosion, resulting in suboptimal peak streamflow forecasting performance, especially when dealing with long streamflow series. This limitation ultimately hinders the predictive accuracy of the decomposition ensemble model. Furthermore, while single-model forecasting (SF) schemes have demonstrated effectiveness, there has been limited exploration of the potential for coupling VMD and encoder-decoder framework in mid- and long-term daily streamflow forecasting. To address these issues and further enhance the capability of common VMD-LSTM model in mid and long-term streamflow forecasting, we have developed a novel and efficient forecast model VMD-LSTM-ED by integrating VMD and LSTM with a robust encoder-decoder structure in the SF scheme. Our proposed method was tested in the Fish River Basin in Maine, USA. To demonstrate its superiority, we also compared VMD-LSTM-ED against LSTM-ED, VMD-LSTM, and LSTM models. The results indicate that the proposed VMD-LSTM-ED exhibits outstanding performance across all aspects, with its advantage becoming more prominent as lead times increase, particularly in peak streamflow forecasting. For example, compared to VMD-LSTM, the Nash-Sutcliffe Efficiency (NSE) of VMD-LSTM-ED increased by 2.91%, 8.45%, 20.2% and 51.2% respectively, at lead times of 1, 3, 5, and 7 days; thus significantly enhancing the long-term prediction ability of VMD-LSTM. [ABSTRACT FROM AUTHOR]

Racial and ethnic disparities persist in cancer survival rates across the United States, despite overall improvements. This comprehensive analysis examines trends in 5-year relative survival rates from 2002–2006 to 2015–2019 for major cancer types, elucidating differences among racial/ethnic groups to guide equitable healthcare strategies. Data from the SEER Program spanning 2000–2020 were analyzed, focusing on breast, colorectal, prostate, lung, pancreatic cancers, non-Hodgkin lymphoma, acute leukemia, and multiple myeloma. Age-standardized relative survival rates were calculated to assess racial (White, Black, American Indian/Alaska Native, Asian/Pacific Islander) and ethnic (Hispanic, Non-Hispanic) disparities, utilizing period analysis for recent estimates and excluding cases identified solely through autopsy or death certificates. While significant survival improvements were observed for most cancers, notable disparities persisted. Non-Hispanic Blacks exhibited the largest gain in breast cancer survival, with an increase of 5.2% points (from 77.6 to 82.8%); however, the survival rate remained lower than that of Non-Hispanic Whites (92.1%). Colorectal cancer survival declined overall (64.7–64.1%), marked by a 6.2% point drop for Non-Hispanic American Indian/Alaska Natives (66.3–60.1%). Prostate cancer survival declined across all races, with Non-Hispanic American Indian/Alaska Natives showing a decrease of 7.7% points (from 96.9 to 89.2%). Lung cancer, acute leukemia, and multiple myeloma showed notable increases across groups. Substantial racial/ethnic disparities in cancer survival underscore the notable need for tailored strategies ensuring equitable access to advanced treatments, particularly addressing significant trends in colorectal and pancreatic cancers among specific minority groups. Careful interpretation of statistical significance is warranted given the large dataset. [ABSTRACT FROM AUTHOR]

Stochastic methods are widely used for the identification of contaminant source information. However, these methods suffer from low computational efficiency. To address this issue, surrogate models can be effectively utilized. In this paper, we propose a Bayesian framework with arbitrary polynomial chaos expansion (BaPC) to simultaneously identify the contaminant source information including contaminant location and release mass-loading rate. We test the applicability of the BaPC for simultaneous identification in a synthetic confined aquifer by the concentration observations from all-time steps multiple times. Our results demonstrate that this approach can efficiently and accurately identify the source information of the contaminant. In addition, the evolution of the contaminant plume can be successfully predicted by employing the estimated contaminant information. It is of crucial importance for the environmental protection and management of groundwater. [ABSTRACT FROM AUTHOR]

This study uses the rational Sine-Gordon expansion (RSGE) method to investigate the dynamical behavior of traveling wave solutions of the water wave phenomena for the time-fractional phi-four equation and the (2 + 1) dimensional Calogero-Bogoyavlanskil schilf (CBS) equation based on the conformable derivative. The technique uses the sine-Gordon equation as an auxiliary equation to generalize the well-known sine-Gordon expansion. It adopts a more broad strategy, a rational function rather than a polynomial one, of the solutions of the auxiliary equation, in contrast to the traditional sine-Gordon expansion technique. Several explanations for hyperbolic functions may be produced using the previously stated approach. The approach mentioned above is employed to provide diverse solutions of the time-fractional phi-four equation and the (2 + 1) dimensional CBS equations involving hyperbolic functions, such as soliton, single soliton, multiple-soliton, kink, cusp, lump-kink, kink double-soliton, and others. The RSGE approach enhances our comprehension of nonlinear processes, offers precise solutions to nonlinear equations, facilitates the investigation of solitons, propels the development of mathematical tools, and is applicable in many scientific and technical fields. The solutions are graphically shown in three-dimensional (3D) surface and contour plots using MATLAB software. All screens display the absolute wave configurations in the resolutions of the equation with the proper parameters. Furthermore, it can be deduced that the physical properties of the found solutions and their characteristics may help us comprehend how shallow water waves move in nonlinear dynamics. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Daily precipitation data from 149 rain gauge stations in China and NCEP—NCAR reanalysis data during 1961–2018 are used to investigate the interdecadal variability of summer precipitation in Northwest China and related causes. The results suggest that, on the interdecadal timescale, Northwest China shifts into a rainy period from the year 1987, with an increase in the precipitation amount and intensity; an increase in the probability of moderate rain, heavy rain, torrential rain, and extremely heavy rain; and a decrease in the probability of light rain. More than 60% of the increase in precipitation can be attributed to rainfall with intensity above the grade of heavy rain. The associated inter-decadal variability of atmospheric circulations over midlatitude Eurasia in summer is examined and it is found that the interdecadal variability is mainly characterized by the Silk Road pattern (SRP), with a cyclonic circulation anomaly and an anticyclonic circulation anomaly over central Asia and Mongolia, respectively; enhanced ascending motion and atmospheric instability in Northwest China; and strengthened easterly winds caused by the Mongolian anti-cyclonic anomaly along the northern boundary of the Tibetan Plateau. On the south side of the Mongolian anticyclone, the water vapor transported from the Pacific and Indian Oceans as well as the South China Sea to Northwest China by easterly winds increases significantly, providing the main water vapor source for the increase in precipitation in Northwest China on the interdecadal timescale. The transition of the Atlantic multidecadal oscillation to a positive phase may be the main cause of the interdecadal transition of the SRP to a positive phase, resulting in the inter-decadal increase in summer precipitation in Northwest China. [ABSTRACT FROM AUTHOR]

Data-driven machine learning surrogates are used to substitute complex groundwater numerical simulation models within optimization algorithms to reduce computational burden for large-scale aquifer management. The traditional surrogate-assisted simulation–optimization modeling has been limited due to uncertainty persisting in surrogate model predictions. More advanced methods are imperative to reduce impact of uncertainties from surrogate models on solution optimality. In this regard, we propose an ensemble surrogate-based simulation–optimization methodology for optimal saltwater intrusion (SWI) control through accounting for uncertainty induced by surrogate models. The optimization model includes two conflicting objectives: minimizing total groundwater pumping and injection rate from an extraction-injection horizontal well system while reducing chloride concentration at monitoring locations below a certain level as much as possible. Three types of machine learning surrogates including artificial neural network, random forest and support vector machine were established to replace a high-fidelity physically based saltwater intrusion model. Optimal Latin hypercube design combined with parallel computing on high performance computing (HPC) was performed to generate input–output data of pumping and injection schedules and resulting salinity levels. An innovative Bayesian set pair analysis approach was presented to derive posterior model weights by considering both training and testing data. The newly constructed individual and ensemble machine learning surrogates were then coupled with a bi-objective optimization model to obtain Pareto-optimal extraction-injection strategies in a deep "2000-foot" sand of the Baton Rouge area, Louisiana, where the optimization was solved using a multi-objective genetic algorithm NSGA-II. Results showed that individual and ensemble surrogate models were accurate enough for salinity prediction. Through comparing the Pareto-optimal solutions, the ensemble surrogate-based modeling was confirmed to provide more reliable and conservative strategies for alleviating saltwater intrusion threat while considerably reducing computational cost. The improved Bayesian set pair analysis approach proved to be robust to integrate multiple models by quantifying model uncertainty. [ABSTRACT FROM AUTHOR]

Many natural compound channels with differential stages play a vital role during high flow events in real-time. When a flood occurs, and water flows into floodplains, the flow structure becomes more complex because of the momentum transfer between sub-segments of the compound channel, caused by the large difference of velocities in different sub-segments. The conventional methods of discharge calculation based on conveyance coefficients of a single channel do not consider momentum transfer, resulting in inaccurate prediction for compound channels. This paper uses a new method of determining conveyance coefficient in compound channels to be incorporated in the two-dimensional analytical solution of the Reynolds averaged Navier–stokes equations for stage-discharge and hydrographs prediction. The proposed conveyance model for flood routing is obtained by solving 1D unsteady flow equations. The flow calculation considers the interaction between sub-segments of compound channels using the momentum equation for shallow water. The proposed model was evaluated to show that incorporating the momentum flux improves the predicted maximum discharge and flow depth in the output hydrographs of the unsteady flow. This result suggests that the proposed method can effectively determine the conveyance coefficient of the compound channel in steady and unsteady flow prediction. [ABSTRACT FROM AUTHOR]

Nitrification is a pivotal step applied in water engineered systems for nitrogen removal. Temperature variation due to seasonal changes is a great challenge for maintaining nitrogen removal efficiency in water engineered ecosystems by affecting nitrifier activities. Research on the abundance, activity, and metabolic characteristics of nitrifiers can provide information for selecting suitable design parameters to ensure efficient nitrogen removal in different seasons. To date, the temperature-related niche separation of comammox, a newly discovered nitrifier with potential high-growth yield, has been rarely investigated. This study addressed the distribution of comammox and canonical nitrifying guilds in drinking water treatment plants (DWTPs) and wastewater treatment plants (WWTPs) in different seasons. qPCR-based surveys showed that comammox ubiquitously distributed and greatly outnumbered other ammonia-oxidizing prokaryotes in both DWTPs and WWTPs, except in Aug samples from DWTPs, suggesting the potential competitive advantage of AOA in summer. The nitrificans-like comammox and nitrosa-like comammox comprised the majority of the comammox community in DWTPs and WWTPs, respectively, and COD and NH4+ concentrations significantly contributed to the distinct comammox phylotype distribution between DWTPs and WWTPs. The temperature-related distribution pattern of the comammox community was observed at each site. Moreover, the network complex of comammox communities was highest in Dec at all the sites, possibly contributing to the survival of comammox community in low temperature conditions. [ABSTRACT FROM AUTHOR]

The spring of 2018 was the hottest on record since 1951 over eastern China based on station observations, being 2.5°C higher than the 1961–90 mean and with more than 900 stations reaching the record spring mean temperature. This event exerted serious impacts in the region on agriculture, plant phenology, electricity transmission systems, and human health. In this paper, the contributions of human-induced climate change and anomalous anticyclonic circulation to this event are investigated using the newly homogenized observations and updated Met Office Hadley Centre system for attribution of extreme events, as well as CanESM2 (Second Generation Canadian Earth System Model) simulations. Results indicate that both anthropogenic influences and anomalous anticyclonic circulation played significant roles in increasing the probability of the 2018 hottest spring. Quantitative estimates of the probability ratio show that anthropogenic forcing may have increased the chance of this event by ten-fold, while the anomalous circulation increased it by approximately two-fold. The persistent anomalous anticyclonic circulation located on the north side of China blocked the air with lower temperature from high latitudes into eastern China. Without anthropogenic forcing or without the anomalous circulation in northern China, the occurrence probability of the extreme warm spring is significantly reduced. [ABSTRACT FROM AUTHOR]

Using the NCEP-2 reanalysis data in 1979-2015, we analyze variations in the coupled stratosphere-troposphere system and attribute them to the polar vortex oscillation (PVO) and the 11-yr sunspot cycle (SC). Subsequently, influences of PVO and SC on the near-ground temperature and extreme temperatures are diagnosed based on observations at 2419 surface stations in China over the same period. Empirical Orthogonal Function (EOF) analysis of geopotential height (GH) anomalies indicates that the first and second EOF modes together can explain nearly 50% of the total variance and they have different driving sources, active periods, and regions. The first EOF mode mainly represents variation characteristics of the polar vortex, and its active periods appear in late winter. It is found that a weakened polar vortex (larger amplitude in the positive time series of the first mode) corresponds to lower daily mean, minimum, and maximum temperatures and more frequent cold nights and days. This cooling effect mainly occur in northeastern China. The second EOF mode is closely related to the SC, and its major active periods are late autumn and early winter. The results reveal that strong solar activity (larger amplitude in the positive time series of the second mode) leads to cooling effects in northern China through accelerating seasonal transformation of the stratospheric circulation and enhancing intensity of the subtropical westerly jet in the upper troposphere and lower stratosphere. The near-ground temperature is lower than usual, especially for daily mean and minimum temperatures. The number of warm nights and days is significantly reduced, and cold nights and days become more frequent. Therefore, the first and second EOF mode time series of GH anomalies can be used as indices of PVO and solar activity, respectively; and can provide indications of winter cooling processes in China. [ABSTRACT FROM AUTHOR]

Plume dilution and reactive mixing can be considerably enhanced by helical flows occurring in three-dimensional anisotropic porous media. In this study, we perform conservative and reactive transport simulations considering different anisotropy structures of a single inclusion with the objective of exploring the effect of the inclusion’s geometry and orientation on the patterns of twisted streamlines and on the overall dilution and reaction of solute plumes. We analyzed 100 different scenarios by varying key parameters such as the angle of the anisotropic structures with respect to the average flow velocity, the spacing between alternated heterogeneous zones of coarse and fine materials, the permeability contrast between such matrices, and the magnitude of the seepage velocity. Entropy conservation equations and entropy-based metrics for both conservative and reactive species were adopted to quantify dilution, reactive mixing and their interactions with the helical flow patterns in the considered three-dimensional anisotropic setups. The results allowed identifying optimal anisotropic configurations maximizing mixing and reactions, and yielding enhancement factors up to 15 times the outcomes of analogous simulations in homogeneous media. Furthermore, the effects of compound-specific diffusive/dispersive properties of the transported species were found to be relevant for both plume dilution and reactive mixing in helical flows. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the variation of microbial communities and functional genes during the biofilm formation in raw water distribution systems without prechlorination and associated effects on the transformation of nitrogen pollutants by using a designed model pipe system. The results showed the transformation of nitrogen pollutants was obvious during the biofilm formation. The richness and diversity of the microbial communities changed significantly. The higher abundance of Nitrospirae in biofilm samples significantly contributed to biological nitrification. In particular, the stable content of Bacteroidetes in the biofilm and soluble microbial products released by the biomass might have enhanced the increase in dissolved organic nitrogen. In addition, the variation tendency of nitrogen functional gene abundances and their strong effects on NH -N, NO -N, and NO -N transformation were clearly observed. These findings provide new insights into the evolution of microbial communities and functional genes during the initial operation period of real-world raw water distribution pipes and highlight management and possible safety issues in the subsequent water treatment process. [ABSTRACT FROM AUTHOR]

We analyze the decadal variation of the stratosphere-troposphere coupled system around the year 2000 by using the NCEP reanalysis-2 data. Specifically, the relationship between the Northern Hemisphere Annular Mode (NAM) and the tropospheric East Asian trough is investigated in order to find the effective stratospheric signals during cold air outbreaks in China. Statistical analyses and dynamic diagnoses both indicate that after 2000, increased stratospheric polar vortex disturbances occur and the NAM is mainly in negative phase. The tropospheric polar areas are directly affected by the polar vortex, and in the midlatitudes, the Ural blocking high and East Asian trough are more active, which lead to enhanced cold air activities in eastern and northern China. Further investigation reveals that under this circulation pattern, downward propagations of negative NAM index are closely related to the intensity variation of the East Asian trough. When negative NAM anomalies propagate down to the upper troposphere and reach a certain intensity (standardized NAM index less than-1), they result in apparent reinforcement of the East Asian trough, which reaches its maximum intensity about one week later. The northerly wind behind the trough transports cold air southward and eastward, and the range of influence and the intensity are closely associated with the trough location. Therefore, the NAM index can be used as a measure of the signals from the disturbed stratosphere to give some indication of cold air activities in China. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The influences of tropospheric blocking high on the stratospheric sudden warming (SSW) and the SSW-induced feedback on the lower atmosphere are analyzed with NCEP (National Center for Environmental Prediction) 2 reanalysis data. Daily mean data from 1979 to 2010 are used to perform statistical and dynamical analyses. According to different distribution features of polar vortex, which can be ascribed to different activities of blocking highs, we have obtained two warming patterns in vortex splitting and displacement patterns. For vortex splitting events, in the Eurasian-North American (ENA) paratype, with disturbances of Atlantic and Aleutian blocking highs, polar vortex is split into two parts that locate at Eurasian and North American continents respectively, while in the Atlantic-East Asian (AEA) paratype, two low-pressure centers derived from the split vortex are situated in the Atlantic and East Asian regions, and two blocking systems occurring in the Urals and North American areas precede these splitting processes. For vortex displacement events, in the Aleutian-Intrusion (AI) paratype, the polar vortex is displaced to the west European and Atlantic areas by the intrusive Aleutian high and this pattern always corresponds to the blocking events occurring in the Pacific basin only. Similarly, the vortex is pushed to the west Eurasian continent by the intrusive North American high-pressure system in the North American-Intrusion (NAI) paratype, which is closely related to the blocking over these areas. The second subject of the research is that whether the anomalous stratospheric signals can be propagated to the lower atmosphere, which is depended on the intensity, duration and position of the disturbed vortex. According to our case studies, geopotential height anomalies can be propagated to the troposphere in strong SSW years, taking about 10-15 d for the decrease from 10 to 500 hPa, leading to apparent variations in the geopotential height and temperature fields. [ABSTRACT FROM AUTHOR]

In this paper, environmentally key properties including aqueous solubilities ( SW), vapor pressures ( VP), sorption coefficients ( KOC), octanol–water ( KOW), octanol–air ( KOA) and air–water ( KAW) partition coefficients of 53 phthalates are studied by the quantitative structure-property relationship models by means of previously proposed Lu index. Reliable models are obtained to estimate Log SW, solubility in air (Log SA), Log KOC and Log KOW for phthalates with the correlation coefficients of estimations ( R) being 0.9869, 0.9461, 0.8880 and 0.9836, and the standard errors being 0.44, 0.27, 0.52 and 0.40, respectively. The predictive ability of the constructed models is demonstrated by the correlation coefficients ( RCV) in the leave-one-out cross validation procedures being 0.9709, 0.9218, 0.8089 and 0.9784, and the corresponding standard errors ( sCV) being 0.47, 0.34, 0.67 and 0.47, respectively. The properties of KAO and KAW for the phthalates are calculated by the predicted SW, SA, and KOW values. [ABSTRACT FROM AUTHOR]

Gas chromatographic and liquid chromatographic retention indices of polyhalogenated biphenyl compounds are successfully modeled by using two 2D descriptors of recently introduced MEDV-13 and atom-type E-state indices derived directly from the molecular structure. A five-variable regression equation was generated for the GC retention indices of 54 PHBs with the correlation coefficient ( R) and relative standard deviation being 0.9921 and 2.4%. Also, a five-variable regression equation was generated for the LC retention indices of 56 PHBs with the correlation coefficient ( R) and relative standard deviation of 0.9831 and 8.0%. The selected indices have been meaningful by using a molecular fragment analysis tool. Additionally, the leave-one-out cross-validation method demonstrates that the obtained models are statistically significant and reliable. [ABSTRACT FROM AUTHOR]

A barcode-based position controlling method for high-speed conditions was introduced to deal with the position control in some conditions where it cannot be done quickly and precisely using traditional methods. The position feedback will depend on the decoding of a specifically redesigned barcode with a special structure. By using the angle encoder and interpolation arithmetic, high precision position deviations can be attained. Then position correction will be done through the control algorithm and servo system. The design and decoding of the barcode and the method of obtaining extremely precise deviation are illuminated. In theory, this method of control servoing is very suitable for its real-time, high-precision and high-speed applicability. [ABSTRACT FROM AUTHOR]

The authors discusses aspects of the study regarding the threats to coastal aquifers including conducted by researchers G. Ferguson and T. Gleeson. The say that Ferguson and Gleeson's conclusion that aquifers are more vulnerable to groundwater extraction than to sea-level rise (SLR) is premature. They also say that the researches used the solution by O. D. L. Strack to estimate the location of the saltwater interface toe in an unconfined coastal aquifer subject.