Search

Copyright of Rare Metals 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.)

Objective To investigate the expression level of serum ubiquitin-conjugating enzyme 2C (UBE2C) and tripartite motif-containing protein 27 (TRIM27) in patients with endometrial cancer (EC) and their correlation with pathological parameters. Methods A total of 96 EC patients from March 2020 to March 2023 were selected as EC group; 65 patients with endometrial atypical hyperplasia (EAH) as EAH group, and 80 healthy subjects as the control group. Enzyme linked immunosorbent assay was applied to analyze the expression level of serum UBE2C and TRIM27. The relationship between serum UBE2C, TRIM27, and pathological data was analyzed; receiver operating characteristic was applied to evaluate the predictive value of serum UBE2C and TRIM27 level for EC. Results The level of serum UBE2C and TRIM27 of EC patients was obviously higher than that in healthy subjects (P < 0.05), and was correlated with tumor diameter, tumor differentiation, lymph node metastasis, FIGO stage, muscle layer invasion depth, cervical involvement, estrogen receptor expression, and progestogen receptor expression (P < 0.05). There was positive correlation between serum UBE2C and TRIM27 (r = 0.475, P < 0.001); and the level of serum UBE2C and TRIM27 was positively correlated with tumor diameter, lymph node metastasis, FIGO stage, and depth of musclular invasion, but negatively with tumor differentiation, estrogen receptor expression, and progestogen receptor expression (P < 0.05). The combination of UBE2C and TRIM27 had obviously higher AUC in evaluating EC than single detection (ZUBE2C-combination=3.406, P < 0.001, ZTRIM27-combination = 3.285, P = 0.001). Conclusion The expression level of UBE2C and TRIM27 in serum of EC patients is up-regulated, which is closely related to pathological parameters. The level of serum UBE2C and TRIM27 can provide reference for early diagnosis of EC. [ABSTRACT FROM AUTHOR]

Aiming at the problem of deterioration of the properties of beta titanium alloy welded joints due to many porosity defects and coarse grains, multi-vibrator ultrasonic-assisted laser welding (M—ULW) technology was used to improve the structure and properties of beta titanium alloy welded joints. The microstructure evolution, tensile strength, elongation, and fracture behavior of the weld joint were studied through scanning electron microscopy, electron back-scatter diffraction, and a universal testing machine. The results show that ultrasonic vibration has no effect on the phase composition of titanium alloy welds during ultrasonic-assisted laser welding. However, it caused all grains in the weld to be transformed into equiaxed grains, and the higher the amplitude, the finer and more uniformly distributed were the equiaxed grains. When the ultrasonic amplitude reached 20 μm, the fine equiaxed crystals were uniformly distributed throughout the weld, and the average grain size of the weld was 56.15 um, which is only one-third of that of the unultrasonicated laser welded joint. Ultrasonic refinement makes the joint grain size decrease, weakens the beta titanium alloy {200} direction weaving, increases the dislocation density within the weld; and increases the tensile strength of the welded joint. The tensile strength of the welded joints exceeded that of the base material by 907 MPa, and the elongation was significantly increased by a factor of 1.8 compared with that of the un-ultrasonicated laser welded joints, resulting in a shift of the fracture location from the center of the weld to the heat-affected zone. [ABSTRACT FROM AUTHOR]

Mesoscale and submesoscale processes have crucial impacts on ocean biogeochemistry, importantly enhancing the primary production in nutrient‐deficient ocean regions. Yet, the intricate biophysical interplay still holds mysteries. Using targeted high‐resolution in situ observations in the South China Sea, we reveal that isopycnal submesoscale stirring serves as the primary driver of vertical nutrient transport to sustain the dome‐shaped subsurface chlorophyll maximum (SCM) within a long‐lived cyclonic mesoscale eddy. Density surface doming at the eddy core increased light exposure for phytoplankton production, while along‐isopycnal submesoscale stirring disrupted the mesoscale coherence and drove significant vertical exchange of tracers. These physical processes play a crucial role in maintaining the elevated phytoplankton biomass in the eddy core. Our findings shed light on the universal mechanism of how mesoscale and submesoscale coupling enhances primary production in ocean cyclonic eddies, highlighting the pivotal role of submesoscale stirring in structuring marine ecosystems. Plain Language Summary: Both physical and biogeochemical processes affect marine ecosystems. Mesoscale cyclonic eddies are known to boost biological productivity by lifting the water in the center of the eddy up to where light is plentiful, which results in a subsurface chlorophyll maximum (SCM) layer. However, the SCM persists long after this eddy lifting process has completed. This study utilizes high‐resolution observations across some eddies to see if smaller, submesoscale processes replenish nutrients by stirring water along density surfaces into the SCM. The results indicate that isopycnal submesoscale stirring plays a significant role, helping the SCM persist within the eddy. We propose that this process might be universal and enhance primary production in all eddy‐rich oceans. Key Points: Isopycnal stirring serves as the primary driver of nutrient supply to sustain subsurface chlorophyll maximum in ocean cyclonic eddiesFrontogenesis and submesoscale centrifugal–symmetric instabilities are the most likely dynamical mechanisms for isopycnal stirring [ABSTRACT FROM AUTHOR]

Sea surface nitrate (SSN) plays an important role in assessing new production and phytoplankton growth in the ocean, yet it has been challenging to estimate SSN from satellites due to its complex and varying relationship with different environmental proxies. The different SSN trends in the northwest Pacific reported in previous studies call for more detailed research to examine the interannual variabilities in SSN. We addressed this problem by developing a stacking‐random‐forest based algorithm for Moderate Resolution Imaging Spectroradiometer (MODIS). It allows estimating SSN from daily sea surface temperature (SST) and Chlorophyll‐a concentration (Chl) at a spatial resolution of 4 km. For SSN ranging between 0.0005 and 25.88 μmol/kg (N = 3,452), the model had a root mean square difference of 1.34 μmol/kg (5.3%) and coefficient of determination of 0.92. Further independent validation and sensitivity tests demonstrated the validity of the algorithm in retrieving SSN. Using this novel data record, for the first time, we investigated the SSN interannual variabilities and trends from MODIS. Overall, the SSN showed a weak decreasing trend of −0.01 ± 0.007 μmol kg−1 yr−1 (p < 0.05) in the northwest Pacific in 2002–2020, associated with an increasing trend in SST (0.03 ± 0.01˚C yr−1 at p < 0.05) and insignificant trend (0.001 ± 0.001 mg m−3 yr−1 at p > 0.05) in Chl. The interannual variabilities of SSN were significantly correlated with the environmental proxies (SST, Chl) and the climate indices (Pacific Decadal Oscillation and North Pacific Gyre Oscillation). The SSN trends can be further restricted with more data available. Plain Language Summary: Nitrate is an important nutrient for phytoplankton growth in the ocean euphotic zone. Due to its complex and varying relationship with different environmental variables, it is very difficult to monitor sea surface nitrate (SSN) from space. The different SSN trends in the northwest Pacific reported in previous studies call for data records of SSN with high spatial and temporal resolution for a better understanding the SSN changes in this region in the past decades. We tackled this problem by developing a machine learning based SSN algorithm from satellites. It allows estimating SSN from daily sea surface temperature and Chlorophyll‐a concentration at a spatial resolution of 4 km. The model was tuned based on extensive historical data set. For a wide range of SSN, the model had an uncertainty of 1.34 μmol/kg (5.3%). Further independent model assessment and sensitivity tests also proved the validity of the algorithm in retrieving SSN from satellites. Using the novel data records of SSN, for the first time, we examined the trends of SSN in the northwest Pacific from satellite remote sensing, and we found weak decreasing trend in SSN in 2002–2020. The climate forcings tend to drive the interannual variabilities of SSN. Key Points: Varying relationships between sea surface nitrate and its predictor variables lead to large uncertainties in its remote estimationA sea surface nitrate satellite algorithm is developed for the northwest Pacific, with significantly reduced uncertaintiesA weak decreasing trend of −0.01 μmol kg−1 yr−1 in sea surface nitrate is identified in the northwest Pacific between 2002 and 2020 [ABSTRACT FROM AUTHOR]

Oceanic submesoscale processes are ubiquitous in the North Pacific Subtropical Gyre (NPSG), where the biological carbon pump is generally ineffective. Due to difficulties in collecting continuous observations, however, it remains uncertain whether episodic submesoscale processes can drive significant changes in particulate organic carbon (POC) export into the mesopelagic ocean. Here we present observations from high-frequency Biogeochemical-Argo floats in the NPSG, which captured the enhanced POC export fluxes during the intensifying stages of a submesoscale front and a cyclonic eddy compared to their other life stages. A higher percentage of POC export flux was found to be transferred to the base of mesopelagic layer at the front compared to that at the intensifying eddy and the mean of previous studies (37% vs. ~10%), suggesting that the POC export efficiency was significantly strengthened by submesoscale dynamics. Such findings highlight the importance of submesoscale fronts for carbon export and sequestration in subtropical gyres. Submesoscale processes are ubiquitous in the North Pacific Subtropical Gyre. The authors show that carbon export efficiency is significantly strengthened under the influence of these episodic features by using high-frequency BGC-Argo observations. [ABSTRACT FROM AUTHOR]

Marine primary producers are largely dependent on and shape the Earth's climate, although their relationship with climate varies over space and time. The growth of phytoplankton and associated marine primary productivity in most of the modern global ocean is limited by the supply of nutrients, including the micronutrient iron. The addition of iron via episodic and frequent events drives the biological carbon pump and promotes the sequestration of atmospheric carbon dioxide (CO2) into the ocean. However, the dependence between iron and marine primary producers adaptively changes over different geological periods due to the variation in global climate and environment. In this review, we examined the role and importance of iron in modulating marine primary production during some specific geological periods, that is, the Great Oxidation Event (GOE) during the Huronian glaciation, the Snowball Earth Event during the Cryogenian, the glacial–interglacial cycles during the Pleistocene, and the period from the last glacial maximum to the late Holocene. Only the change trend of iron bioavailability and climate in the glacial–interglacial cycles is consistent with the Iron Hypothesis. During the GOE and the Snowball Earth periods, although the bioavailability of iron in the ocean and the climate changed dramatically, the changing trend of many factors contradicted the Iron Hypothesis. By detangling the relationship among marine primary productivity, iron availability and oceanic environments in different geological periods, this review can offer some new insights for evaluating the impact of ocean iron fertilization on removing CO2 from the atmosphere and regulating the climate. [ABSTRACT FROM AUTHOR]

Published radiotherapy data for canine intraventricular tumours are limited. In this retrospective, longitudinal study (9/2011–2018), 11 dogs with intraventricular masses were treated with stereotactic radiotherapy (SRT). Pathologic diagnosis was available from surgery or necropsy in 6/11 cases, revealing choroid plexus papilloma (3) or carcinoma (2), and ependymoma (1). The remainder were magnetic resonance imaging (MRI)‐diagnosed as suspected choroid tumours or ependymomas. Tumours were located in the third or lateral ventricle (8), fourth ventricle (2), and cerebellopontine angle (1). Surgery was performed in three dogs prior to radiotherapy, and all showed gross residual/recurrent disease at treatment. Dogs received 8 Gray × 3 fractions (7), or 15 Gray × 1 fraction (4). Ten dogs were deceased at analysis, and one was living. The estimated median overall survival time (OS) from first SRT treatment was 16.9 months (515 days, 95% CI 33–1593 days). The survival time for two pathology‐diagnosed carcinoma dogs were 24 and 133 days, respectively, and survival time for dogs with moderate to marked ventriculomegaly (4/11) ranged from 24 to 113 days. A total of 10/11 showed clinical improvement per owner or clinician, but two had short‐lived benefits and were euthanized within 6 weeks of SRT. Limited conclusions on radiation‐specific complications are possible due to the small dataset and limited follow‐up imaging. This study provides preliminary evidence that radiotherapy outcomes are variable with intraventricular tumours, and some long‐term survivors are noted. [ABSTRACT FROM AUTHOR]

The mechanism that determines the dynamics of subsurface chlorophyll maximum depth (zSCM) has long been debated. Although a coupling between zSCM and the top of nitracline (znit) has been widely observed in the open ocean, a co‐location of zSCM and an isolume depth (ziso) has often been reported in oligotrophic waters. In this study, based on continuous observations of ten BGC‐Argo floats, we found that the seasonal displacement of zSCM in all subtropical gyres was driven mainly by light, but zSCM displayed a nutrient‐driven pattern occasionally when znit became shallower than ziso. We therefore proposed a "two‐group competition framework": zSCM in subtropical gyres is determined by the competition of two phytoplankton groups, nutrient‐sensitive picoeukaryotes and light‐sensitive Prochlorococcus. When znit (ziso) is shallower than ziso (znit), picoeukaryotes (Prochlorococcus) dominate the chlorophyll biomass at the SCM, and thus zSCM follows znit (ziso). This paradigm reconciles the inconsistent conclusions drawn from earlier studies. Plain Language Summary: Phytoplankton growth requires both light and nutrients. In most open oceans, the vertical distribution of the chlorophyll‐a concentration generally is a maximum at a subsurface depth because of nutrient depletion in surface waters and inadequate light at depth. We took advantage of the continuous observations from autonomous profiling floats of the chlorophyll maximum depth in oligotrophic subtropical oceans. Our analysis of those data showed that the depth of the chlorophyll maximum depth in these areas usually followed either the depth where there was enough light for phytoplankton to grow or the depth where there were enough nutrients for them to grow. This discovery suggests that two different groups of phytoplankton determine where the chlorophyll maximum appears. One group is sensitive to nutrient supply and responds more quickly to variations of nutrient supply than of light, and the other group is sensitive to light availability and responds more quickly to variations of light than of nutrient supply. The depth of the chlorophyll maximum is determined by the interaction between light and nutrient availability, which determines which group dominates. Key Points: The displacement of subsurface chlorophyll maximum (SCM) depth in subtropical gyres is mainly driven by the isolume depth, which is generally above the top of nitraclineThe top of nitracline impacts the SCM depth when it occasionally becomes above the isolume depth, displaying a nutrient‐driven SCM patternThe dynamics of SCM depth are likely due to the competition of light‐sensitive Prochlorococcus and nutrient‐sensitive picoeukaryotes [ABSTRACT FROM AUTHOR]

Wind power input to oceanic near‐inertial oscillations (NIOs) plays a crucial role in sustaining the global ocean conveyor belt. However, the impact of tropical cyclones (TCs) on wind power input to NIOs, despite being the most vigorous atmospheric dynamics capable of exciting NIOs, is often overlooked in global estimations due to their transient nature and a lack of observations. Utilizing hourly wind and ocean current records, we quantified the wind power on NIOs induced by TCs from 1990 to 2019. Our findings reveal that the wind power on NIOs due to TCs is estimated to be between 0.028 and 0.065 TW, which accounts for a significant proportion, that is, 8%–17%, of that over the globe. This study highlights the importance of incorporating the wind power induced by TCs when estimating the global wind power on NIOs, as its impact is non‐negligible. Our findings contribute to a better understanding of the global energy balance by improving the estimation of wind power on NIOs. Plain Language Summary: Wind power input to oceanic near‐inertial oscillations (NIOs) is important for sustaining the global ocean conveyor belt. However, the influence of tropical cyclones (TCs) on wind power input to NIOs, despite being the most intense atmospheric dynamics that could easily excite NIOs, is often overlooked in global estimations due to their transient nature and a lack of observations. By analyzing wind and ocean current records from 1990 to 2019, the wind power on NIOs induced by TCs was quantified. We found that wind power on NIOs due to TCs is non‐negligible and accounts for a significant portion of that over the globe. This study highlights the importance of considering the wind power induced by TCs when estimating the global wind power on NIOs, which helps to achieve a more accurate estimation of wind power on NIOs, leading to an improved understanding of the global energy balance. Key Points: Observed data shows tropical cyclones contribute 8%–17% of global wind power on near‐inertial oscillationsTropical cyclones could contribute up to 90% of wind power on near‐inertial oscillations in their prone regionsAccounting for tropical cyclones is essential when estimating wind power on near‐inertial oscillations [ABSTRACT FROM AUTHOR]

The Indian Ocean Dipole (IOD) plays a crucial role in shaping local and global environments, yet its effects on interannual variability of the Arabian Sea oxygen minimum zone (ASOMZ) remains poorly understood. Here, we used a coupled physical‐biogeochemical model to investigate the dynamical response of the ASOMZ to extreme negative (2016) and positive (2019) IOD events. Our findings revealed that the suboxic area of the ASOMZ reduced (expanded) by ∼27% (∼28%) after the negative (positive) IOD event. Compared to the 2019 pIOD event, approximately 2.5 times more oxygen‐rich water was delivered into the Arabian Sea during the 2016 nIOD event, replenishing dissolved oxygen (DO) consumed by intensified upwelling‐induced enhanced remineralization of particulate organic matter (POM), thereby increasing the DO concentration in the Gulf of Aden. Conversely, more POM from the western Arabian Sea was transported to the central Arabian Sea, leading to a subsequent decrease in DO concentration there. Plain Language Summary: The Indian Ocean Dipole (IOD) is a climate phenomenon that sea surface temperature in the western Indian Ocean becomes alternately warmer (positive phase) and then colder (negative phase) than the eastern Indian Ocean south of Indonesia. This variability significantly impacts global atmospheric circulation and environments. The Arabian Sea oxygen minimum zone (ASOMZ) is an area in the Arabian Sea characterized by low dissolved oxygen (DO) levels, which can have adverse effects on marine life. We used a model to examine how extreme IOD events influence the ASOMZ. The results suggested that during the negative IOD event in 2016, the suboxic area of the ASOMZ decreased by approximately 27%, while it expanded by approximately 28% during the positive IOD event in 2019. The response of the ASOMZ to IOD events in the Gulf of Aden was primarily modulated by physical factors, such as the Somali Coastal Current and local upwelling. On the other hand, the ASOMZ in the central Arabian Sea was regulated by a combination of biological and physical processes. These findings contributed to our understanding of the ASOMZ's response to IOD events, which is essential for studying the Arabian Sea's marine ecosystem. Key Points: The response of the Arabian Sea oxygen minimum zone to the Indian Ocean Dipole events in the Gulf of Aden was modulated by physical factorsThe Arabian Sea oxygen minimum zone in the central Arabian Sea was regulated by both biological and physical processesThe upper edge of the Arabian Sea oxygen minimum zone invaded the lower euphotic zone (100–200 m) under the impact of Indian Ocean Dipole events [ABSTRACT FROM AUTHOR]

Subtropical gyres cover 26%–29% of the world's surface ocean and are conventionally regarded as ocean deserts due to their permanent stratification, depleted surface nutrients, and low biological productivity. Despite tremendous advances over the past three decades, particularly through the Hawaii Ocean Time‐series and the Bermuda Atlantic Time‐series Study, which have revolutionized our understanding of the biogeochemistry in oligotrophic marine ecosystems, the gyres remain understudied. We review current understanding of upper ocean biogeochemistry in the North Pacific Subtropical Gyre, considering other subtropical gyres for comparison. We focus our synthesis on spatial variability, which shows larger than expected dynamic ranges of properties such as nutrient concentrations, rates of N2 fixation, and biological production. This review provides new insights into how nutrient sources drive community structure and export in upper subtropical gyres. We examine the euphotic zone (EZ) in subtropical gyres as a two‐layered vertically structured system: a nutrient‐depleted layer above the top of the nutricline in the well‐lit upper ocean and a nutrient‐replete layer below in the dimly lit waters. These layers vary in nutrient supply and stoichiometries and physical forcing, promoting differences in community structure and food webs, with direct impacts on the magnitude and composition of export production. We evaluate long‐term variations in key biogeochemical parameters in both of these EZ layers. Finally, we identify major knowledge gaps and research challenges in these vast and unique systems that offer opportunities for future studies. Plain Language Summary: Vast subtropical oceans feature basin‐wide anticyclonic gyres, which restrict vertical supplies of nutrients, resulting in low surface nutrient concentrations and generally low rates of biological production. The subtropical gyres have therefore traditionally been regarded as ocean deserts. Through a comprehensive data re‐analysis focusing on the North Pacific Subtropical Gyre, we find larger than expected spatiotemporal variability in biogeochemical properties in subtropical gyres, including the distribution of nutrients, N2 fixation, and biological production. Such variations are most pronounced through the sunlit water column (euphotic zone [EZ]), including sharp gradients in nutrient concentrations and sources and microbial community structure. Based on analysis and synthesis conducted in this study, we show evidence for the functioning of a two‐layer EZ habitat, with each layer differentiated primarily by inputs of sunlight and nutrients. Our understanding of long‐term biogeochemical variability is relatively restricted, owing to a lack of reliable long‐term observations at adequate spatial scales. We therefore urge the development and use of higher temporal and spatial resolution sampling strategies, for example, through the use of autonomous sampling platforms, that will allow for a greater understanding of biogeochemical processes and facilitate improvements in numerical modeling capabilities. Key Points: Subtropical gyres display larger spatiotemporal dynamics in biogeochemical properties than previously consideredAn improved two‐layer framework is proposed for the study of nutrient‐driven and biologically mediated carbon export in the euphotic zoneFuture research will benefit from high‐resolution samplings, improved sensitivity of nutrient analyses, and advanced modeling capabilities [ABSTRACT FROM AUTHOR]

Frequent fishing activities are causing overfishing, destroying the habitat of marine life, and threatening global marine biodiversity. Understanding the dynamics of fishing activities and their drivers is crucial for designing and implementing effective ocean management. The fishing activities in the open sea are reported to be characterized by high spatial variability in local waters; however, it is still unclear whether their high spatial variability is random or regulated by oceanographic variations. Mesoscale eddies are ubiquitous swirling currents that dominate locally biogeochemical processes. Previous case studies presented an ongoing debate regarding how eddies exert impacts on high trophic organisms, which imposes limitations on understanding the dynamics of fishing activities based on the bottom‐top control hypothesis from eddies to fish and fishing activities. By combining global fishing activities from deep learning and oceanic eddy atlases from satellite monitoring, we showed that the spatial variations in fishing activities were closely related to mesoscale eddies in the global midlatitude ocean, confirming that fishing activities primarily targeting tuna, were aggregated in (repelled from) anticyclonic (cyclonic) eddy cores. This eddy‐fishing activity relationship was opposite to satellite‐observed primary production but corresponded well with the temperature and oxygen content in deeper water. By integrating existing evidence, we attribute eddy‐related fishing activities to a reasonable hypothesis that warm and oxygen‐rich deeper water in anticyclonic eddies relieves the thermal and anoxic constraints for diving predation by tuna while the constraints are aggravated in cold and oxygen‐poor cyclonic eddies. [ABSTRACT FROM AUTHOR]

Simple Summary: Canine oligodendrogliomas are universally fatal primary brain tumors. Glioma-associated microglia/macrophages (GAMs) have been shown to contribute to immunosuppression and tumor progression in human glioblastoma (GBM). While a robust GAM infiltrate has been observed in canine oligodendrogliomas, their corresponding molecular signature has not previously been explored. The results of this study show that GAMs variably infiltrate canine oligodendrogliomas. We observed marked differences in GAM density within individual tumors and across tumors. We further observed elevations in several GAM-derived pro-tumorigenic molecules, suggesting that GAMs likely contribute to canine oligodendroglioma pathogenesis. However, similar to GAM density, the tumor tissue expression of the majority of molecules assayed demonstrated significant variability. This is in contrast to our previous work on canine astrocytomas, which more consistently demonstrated robust increases in several GAM-derived pro-tumorigenic molecules. This study raises the possibility that the immune microenvironment across oligodendrogliomas and astrocytomas has key differences which may be relevant to future therapeutic targeting. The goal of this study was to define the glioma-associated microglia/macrophage (GAM) response and associated molecular landscape in canine oligodendrogliomas. Here, we quantified the intratumoral GAM density of low- and high-grade oligodendrogliomas compared to that of a normal brain, as well as the intratumoral concentration of several known GAM-derived pro-tumorigenic molecules in high-grade oligodendrogliomas compared to that in a normal brain. Our analysis demonstrated marked intra- and intertumoral heterogeneity of GAM infiltration. Correspondingly, we observed significant variability in the intratumoral concentrations of several GAM-associated molecules, unlike what we previously observed in high-grade astrocytomas. However, high-grade oligodendroglioma tumor homogenates (n = 6) exhibited an increase in the pro-tumorigenic molecules hepatocyte growth factor receptor (HGFR) and vascular endothelial growth factor (VEGF), as we observed in high-grade astrocytomas. Moreover, neoplastic oligodendrocytes displayed robust expression of GAL-3, a chimeric galectin implicated in driving immunosuppression in human glioblastoma. While this work identifies shared putative therapeutic targets across canine glioma subtypes (HGFR, GAL-3), it highlights several key differences in the immune landscape. Therefore, a continued effort to develop a comprehensive understanding of the immune microenvironment within each subtype is necessary to inform therapeutic strategies going forward. [ABSTRACT FROM AUTHOR]

Background: Horner syndrome often occurs with cervical myelopathies and might provide insight into the underlying disease and prognosis. Objectives: To describe the clinical and imaging features of dogs with cervical myelopathy and concurrent Horner syndrome and to determine association of Horner syndrome with diseases or magnetic resonance images (MRI). Animals: Ninety‐three client‐owned dogs with cervical myelopathy and concurrent Horner syndrome and 99 randomly selected client‐owned dogs with cervical myelopathy without Horner syndrome (control cases). Methods: Retrospective study. Medical records were reviewed to identify Horner and control cases and clinical findings recorded. MRI were reviewed, and lesions characterized and recorded. Descriptive and comparative statistics were performed. Results: Non‐compressive disease occurred more frequently in the Horner group compared with controls (58%; 95% CI: 48‐68 vs 9%; 95% CI: 5‐16; P <.0001). The most common diseases were fibrocartilaginous embolism in the Horner group (44/93; 47%) and intervertebral disc extrusion (76/99; 77%) amongst controls. On MRI, parenchymal hyperintensity was seen more commonly in the Horner group (95%; 95% CI: 88‐98) compared with controls (51%; 95% CI: 41‐60; P <.0001). In the Horner group, dogs that did not survive to discharge (N = 13) had more extensive MRI lesions relative to the adjacent vertebral length (200%; IQR 110%‐575%) compared with survivors (N = 80; 110%; IQR 40%‐250%; P =.02). Lateralization of Horner signs and MRI changes matched in 54% of cases. The overall survival rate was high in both Horner (80/93; 86%) and control (95/99; 96%) groups. Conclusions and Clinical Importance: Horner syndrome in cervical myelopathy is commonly associated with noncompressive intraparenchymal disease. [ABSTRACT FROM AUTHOR]

Internal waves (IWs) are small-scale physical processes that occur frequently in stratified marginal seas. IWs are ubiquitous and well documented in the northern South China Sea (nSCS), but few studies have explored the ecosystem responses to the IWs. MODISA chlorophyll-a (Chl-a) data from 2002 to 2014 were used to examine the distribution of Chl a near the Dongsha Atoll (DSA). Composite Chl a from about 40 IWs during spring and summer showed stronger response on the northern side than on the southern side of the DSA. One day after the passage of IWs, composite surface Chl a on the northern side increased from 0.11 mg/m3 to a maximum mean value of 0.18 mg/m3. It decreased to 0.13 mg/m3 after two days and maintained that level for several days after the passage of IWs. The enhanced surface Chl a likely caused subsurface Chl-a maximum and nutrients in the surface layer. Approximately 64% of the increase in surface Chl a was due to the uplift of the subsurface Chl-a maximum one day after the passage of IWs, while nutrient-induced new phytoplankton growth contributed about 18% of the increase a few days later. When the IWs occurred frequently in spring and summer, Chl-a level on the northern side was about 30% higher than that on the southern side. IW dissipation and its impact on nutrients and chlorophyll were stronger on the northern side of the DSA than on the south, which caused a north-south asymmetric distribution of Chl a in the region. [ABSTRACT FROM AUTHOR]

The international Argo program, a global observational array of nearly 4 000 autonomous profiling floats initiated in the late 1990s, which measures the water temperature and salinity of the upper 2 000 m of the global ocean, has revolutionized oceanography. It has been recognized one of the most successful ocean observation systems in the world. Today, the proposed decade action "OneArgo" for building an integrated global, full-depth, and multidisciplinary ocean observing array for beyond 2020 has been endorsed. In the past two decades since 2002, with more than 500 Argo deployments and 80 operational floats currently, China has become an important partner of the Argo program. Two DACs have been established to process the data reported from all Chinese floats and deliver these data to the GDACs in real time, adhering to the unified quality control procedures proposed by the Argo Data Management Team. Several Argo products have been developed and released, allowing accurate estimations of global ocean warming, sea level change and the hydrological cycle, at interannual to decadal scales. In addition, Deep and BGC-Argo floats have been deployed, and time series observations from these floats have proven to be extremely useful, particularly in the analysis of synoptic-scale to decadal-scale dynamics. The future aim of China Argo is to build and maintain a regional Argo fleet comprising approximately 400 floats in the northwestern Pacific, South China Sea, and Indian Ocean, accounting for 9% of the global fleet, in addition to maintaining 300 Deep Argo floats in the global ocean (25% of the global Deep Argo fleet). A regional BGC-Argo array in the western Pacific also needs to be established and maintained. [ABSTRACT FROM AUTHOR]

An unprecedented warm sea surface temperature (SST) anomaly event, namely, the Blob, occurred in the northeast Pacific during the winter (October–January) of 2013/2014, causing substantial economic and ecological impacts. Here, we explore the driving forces of the Blob from both atmospheric and oceanic perspectives and show that the Blob primarily resulted from weak wintertime cooling due to the reduced air-sea heat flux transfer from the ocean to the atmosphere and the reduced horizontal advection of cold water in the upper ocean. Both mechanisms were attributed to an anomalous high-pressure system over the study region. Specifically, the anomalous air-sea heat flux, which was dominated by turbulent heat flux anomalies, was mainly induced by the increased air temperature (i.e., with a contribution of approximately 70%) and the weakened wind speed associated with the high-pressure system. The reduced horizontal heat advection was mainly due to the weakened winds acting on the ocean temperature meridional gradient. Using a regional ocean numerical model with different experimental runs, we evaluated the contributions of air temperature and wind drivers to the Blob at both the surface and subsurface of the ocean. The Blob was absent when the model was forced by climatology-air-temperature. Both the SST and integrated ocean heat content (OHC, 0–150 m) decreased, and the mixed layer depth (MLD) was deeper than that in the control run forced by real atmospheric conditions. In the climatology-winds experiment, obvious warm anomalies still existed, which were similar to but weaker than the control run. The SST (OHC) and MLD values in the climatology-winds run were between those of the climatology-air-temperature run and the control run. Compared to former studies that attribute the formation of the Blob to an anomalous air-sea heat flux and horizontal advection mainly induced by reduced winds, our study demonstrates that anomalous warm air temperatures played a more important role in its formation. [ABSTRACT FROM AUTHOR]

Nutrient reallocation The nutrient reallocation feedback mentions that if nutrients are not consumed by I Sargassum i , they would go to phytoplankton which is supposed to have lower PIC:POC ratios compared to I Sargassum i . Calcification The calcification feedback argues that CO SB 2 sb production due to the formation of carbonate shells attached to the surface of I Sargassum i can cancel most of the photosynthetic uptake of CO SB 2 sb . Since phytoplankton has similar or even higher ratios of PIC:POC, nutrient reallocation to I Sargassum i is favorable for CDR given the reasons stated above. Even if the nutrient reallocation effect is considered, the PIC compensation effect by phytoplankton is underestimated by picking a low PIC:POC ratio (0.01) for phytoplankton[11], [12]. [Extracted from the article]

In addition to nutrients and light, temperature plays a crucial role in marine biogeochemical processes. In this study, the sensitivity of the growth rate of phytoplankton to temperature was systematically studied by using a two-level nested physical–biogeochemical coupled model for the Yangtze River estuary of the East China Sea. The physical component of the coupled model is configured from the Regional Ocean Modeling System (ROMS) with the highest horizontal resolution of 3 km. The biogeochemical component of the coupled model is based on the carbon, silicon and nitrogen ecosystem model (CoSiNE). Five specific growth rate of phytoplankton equations with different relation to temperature were tested with the objective of reproducing the temporal evolution of chlorophyll concentration as observed by SeaWiFS. Our results indicate that the specific growth rate of phytoplankton equation which is from Geider's work, reaches a maximum at 22 °C and remains constant with higher temperature, can reproduce the seasonal variation of chlorophyll very well, and may be suitable for application in the physical–biogeochemical coupled model (ROMS-CoSiNE) of the Yangtze River estuary. [ABSTRACT FROM AUTHOR]

Contrasting decrease and increase trends of sea surface temperature (SST) have been documented in the western Subarctic (WSA) and the rest of the Northwest Pacific (NWP) from 1958 to 2017, respectively. Consequently, more (less) total carbon dioxide (TCO2) due to ocean cooling (warming) is transported to the surface, which leads to increase (decrease) of oceanic surface partial pressure of carbon dioxide (pCO2). With the combined influence of the rising atmospheric carbon dioxide (CO2) level and changing ocean conditions, a prominent increase in oceanic surface pCO2 occurred with different rates of increase in summer and winter in the NWP. The oceanic surface pCO2 is mainly controlled by the variation of TCO2 at the interdecadal timescale and by SST at the seasonal timescale. Our results also indicate that increasing SST tends to strengthen the capability of ocean in absorbing anthropogenic CO2 in the NWP, while ocean's uptaking ability is weakened in the cooling area of the WSA. [ABSTRACT FROM AUTHOR]

Fast repetition rate fluorometry (FRRf) allows for rapid non-destructive assessment of phytoplankton photophysiology in situ yet has rarely been applied to Trichodesmium. This gap reflects long-standing concerns that Trichodesmium (and other cyanobacteria) contain pigments that are less effective at absorbing blue light which is often used as the sole excitation source in FRR fluorometers—potentially leading to underestimation of key fluorescence parameters. In this study, we use a multi-excitation FRR fluorometer (equipped with blue, green, and orange LEDs) to investigate photophysiological variability in Trichodesmium assemblages from two sites. Using a multi-LED measurement protocol (447+519+634 nm combined), we assessed maximum photochemical efficiency (F v / F m ), functional absorption cross section of PSII (σ PSII ), and electron transport rates (ETRs) for Trichodesmium assemblages in both the Northwest Pacific (NWP) and North Indian Ocean in the vicinity of Sri Lanka (NIO-SL). Evaluating fluorometer performance, we showed that use of a multi-LED measuring protocol yields a significant increase of F v / F m for Trichodesmium compared to blue-only excitation. We found distinct photophysiological differences for Trichodesmium at both locations with higher average F v / F m as well as lower σ PSII and non-photochemical quenching (NPQ NSV ) observed in the NWP compared to the NIO-SL (Kruskal–Wallis t -test df = 1, p < 0.05). Fluorescence light response curves (FLCs) further revealed differences in ETR response with a lower initial slope (α ETR ) and higher maximum electron turnover rate (E T R P S I I m a x ) observed for Trichodesmium in the NWP compared to the NIO-SL, translating to a higher averaged light saturation E K (= E T R P S I I m a x /α ETR ) for cells at this location. Spatial variations in physiological parameters were both observed between and within regions, likely linked to nutrient supply and physiological stress. Finally, we applied an algorithm to estimate primary productivity of Trichodesmium using FRRf-derived fluorescence parameters, yielding an estimated carbon-fixation rate ranging from 7.8 to 21.1 mgC mg Chl-a–1 h–1 across this dataset. Overall, our findings demonstrate that capacity of multi-excitation FRRf to advance the application of Chl-a fluorescence techniques in phytoplankton assemblages dominated by cyanobacteria and reveals novel insight into environmental regulation of photoacclimation in natural Trichodesmium populations. [ABSTRACT FROM AUTHOR]

The South China Sea (SCS) is the largest semi-enclosed marginal sea in the western Pacific. The alternation of East Asian monsoon causes a significant seasonal pattern of chlorophyll, primary productivity, and export flux of sinking particles. However, the source and sink of dissolved organic carbon (DOC) pools with different bioavailability are less studied. Here we evaluated the seasonal production of DOC in labile, semi-labile and refractory forms using a coupled physical-biogeochemical model. This study aims to understand the dynamics and budgets of organic matters in the SCS. Model results show that the production of labile, semi-labile and refractory DOC is highly correlated with the net primary productivity (NPP) which is higher in winter and lower in summer, reflecting a dependence of DOC on the NPP. The seasonal variation in Pearl River discharge dominates the DOC production in the northern coastal region. In the northeast, the Kuroshio intrusion associated frontal system is attributed to cause high winter production. The DOC production in the southwest is controlled by both winter mixing and summer upwelling. The production of refractory DOC with the least bioavailability favors carbon sequestration. Its annual mean production is 1.8±0.5 mg C m−2 d−1, equivalent to 26% of the export flux of particulate organic carbon at 1000 m. [ABSTRACT FROM AUTHOR]

During the northeast monsoon season, Zhe-Min Coastal Current (ZMCC) travels along the Chinese mainland coast and carries fresh, cold, and eutrophic water. ZMCC is significantly important for the hydrodynamic processes and marine ecosystems along its path. Thus, this bottom-trapped plume deserves to be further discussed in terms of the major driving factor, for which different opinions exist. For this purpose, in this study, a high resolution Semi-implicit Cross-scale Hydroscience Integrated System Model (SCHISM) is established and validated. High correlation coefficients exist between along-shelf wind speeds and seasonal variations of both ZMCC volume transport and the freshwater signal. These coefficients imply that the wind is important in regulating ZMCC. However, for similar annual mean ZMCC volume transports, the extreme south boundaries of Zhe-Min Coastal Water (ZMCW) are different among different years. This difference is attracting attention and is explored in this study. According to the low wind/discharge experiment, it was found that although the volume transport of ZMCC is more sensitive to the variation of local wind speeds, the carried freshwater is limited by the Changjiang River discharge, which ultimately determines the south boundary of ZMCW. The momentum analysis at transects I and II shows that, for driving ZMCC, the along-shore wind forcing is as important as the buoyancy forcing. Note that this conclusion is supported by a zero-discharge experiment. It was also found that the buoyancy forcing varies with respect to time and space, which is due to variations of the discharge of Changjiang River. In addition, a particle tracking experiment shows that the substance carried by the Changjiang River diluted water would distribute along the Zhe-Min coastal region during the northeast monsoon season and it may escape due to the wind relaxation. [ABSTRACT FROM AUTHOR]

A 3D unstructured‐grid ocean circulation model covering the continental shelf and coastal seas around New England is used to investigate freshwater transport (FWT) on the Scotian Shelf (SS) and its impact on the salinity in the Gulf of Maine (GoME). The model was first validated using observed elevation, velocity, temperature, and salinity at multiple locations, demonstrating generally high model skills. Intraseasonal variabilities of freshwater fluxes in 2017 and 2018 were then analyzed across different transects around SS and Browns Bank (BB). These indicated that the flow pattern in SS during 2017 was consistent with previous understanding: low salinity water flows southwestward along the shelf and turns into the GoME around BB. However, in 2018, most of the low salinity water did not enter the GoME, but was transported to the open ocean. The most striking difference occurred early in the year when the FWT, normally at its maximum, was practically stopped by an anticyclonic eddy impinging upon the shelf break near the western end of SS. Then in March, in contrast to the prevailing eastward wind, two southwestward wind events occurred that induced an excessive amount of FWT in SS. We further showed that when anticyclonic eddies impinge on the shelf break, the typical geostrophic balance associated with southwestward flow is interrupted, and a new geostrophic balance is established with the directions of pressure gradient force and flow reversed. The influence from anticyclonic eddies explains the abnormally low FWT in SS and higher GoME salinity in 2018. Plain Language Summary: In this research, we built an ocean circulation model around New England area and verified the model performance in capturing the variations of water level, velocity, temperature, and salinity. We used this model to analyze the movement of freshwater content that is contained in the seawater on the Scotian Shelf (SS) in 2017–2018, and studied its influence on the salinity in the downstream Gulf of Maine (GoME). The model shows that in 2017 the freshwater flew southwestward along the SS and then entered into the GoME, while in 2018 most of the freshwater did not enter the GoME, but went to the open ocean. The absence of freshwater input from the SS was caused by frequent anticyclonic eddies around the SS, which resulted in higher salinity in the GoME. In addition, we found that the southwestward wind can significantly increase the freshwater flow on the SS. Key Points: NorthEast Shelf Seas model was constructed and validated to study freshwater transport (FWT) in the Scotian Shelf (SS)Southwestward wind can significantly increase the FWT in the SSAnticyclonic eddies blocked the FWT in the SS resulting in higher Gulf of Maine salinity in 2018 [ABSTRACT FROM AUTHOR]

Sea surface nitrate (SSN) is an important parameter to characterize physical and biogeochemical processes, particularly to quantify oceanic new primary production, yet its remote estimation from satellite has been difficult due to the complex relationships between environmental variables and SSN. In the central and southern sections of the California Current System (CSCCS), this challenge is attempted through modeling, validation, and extensive tests in different oceanic scenarios. Specifically, using extensive SSN datasets collected by many cruises spanning 40 years (1978–2018) and Moderate Resolution Imaging Spectroradiometer (MODIS) estimated sea surface temperature (SST) and chlorophyll-a (Chl), a stacking random forest (SRF) model of SSN has been developed and validated with a spatial resolution of ~4 km. The model showed an overall performance of root mean square difference (RMSD) $=0.83\,\,\mu $ mol/kg, with coefficient of determination ($R^{2}) =0.87$ , mean bias $= -0.11\,\,\mu $ mol/kg, and mean ratio = 1.15 for SSN ranging between 0.05 and $19.90~\mu $ mol/kg ($N =1034$). Furthermore, tests of the model with its original parameterization for the upwelling period, oceanic period, and winter period all showed satisfactory performance with an overall RMSD of 1.95 $\mu $ mol/kg. The sensitivity of the SRF model to uncertainties of MODIS SST and Chl was examined, with induced uncertainties of $\le 2.22~\mu $ mol/kg. The extensive evaluation and sensitivity tests indicated the robustness of the SRF model in estimating SSN in the study area of the CSCCS, and it could serve as a robust approach for other regions once sufficient in situ SSN data are available for model calibration. [ABSTRACT FROM AUTHOR]

Purpose: c-MYC plays an important role in regulating cellular growth and apoptosis, and it is aberrantly expressed in many human malignancies. Although c-MYC has been extensively investigated in Burkitt lymphoma and diffuse large B cell lymphoma, little has been reported in anaplastic large cell lymphoma (ALCL). The aim of this study was to investigate the expression and genetic alterations of c-MYC in primary systemic ALCL, characterize its clinicopathologic features and immunophenotypes, and discuss their implications in prognosis. Methods: Tissue microarrays using samples from 85 ALCL patients were used to evaluate expression of c-MYC and anaplastic lymphoma kinase (ALK). c-MYC and ALK genetic alterations were detected using fluorescence in situ hybridization. The Kaplan–Meier and multivariate Cox regression methods were used for survival analysis. Results: c-MYC was expressed in 24 of 85 samples (28.2%), and ALK was expressed in 54 (63.5%). c-MYC and ALK were co-expressed in 16 samples (18.8%). c-MYC expression and c-MYC and ALK co-expression increased with ALCL clinical stages and the International Prognostic Index (IPI) score (p < 0.05). Fifty of the samples (58.8%) had ALK rearrangement, and 18 (22.1%) had aneuploidy. c-MYC rearrangement was not detected, but aneuploidy was observed in 19 cases (22.4%). c-MYC aneuploidy was significantly different based on c-MYC expression and the IPI score (p < 0.05). c-MYC was a significant independent prognostic factor for progression-free survival and overall survival in patients with ALCL. Conclusion: c-MYC protein expression and c-MYC aneuploidy could predict worse survival in patients with ALCL. [ABSTRACT FROM AUTHOR]

Photoacclimation is a photo‐physiological mechanism of phytoplankton associated with the modulation of the ratio of phytoplankton chlorophyll (Chl) and carbon (C), yet little is known on how it modulates Chl dynamics and the Chl‐C coupling relationship in the mid‐latitude oceans. In this study, Chl and C estimated from optical sensors on three BGC‐Argo floats, provided a record of the biomass and physiological variability at high temporal and vertical resolutions in the mid‐latitude northwest Pacific. It is found that, despite the Chl seasonal cycle being mainly dominated by variability in biomass, Chl and C became decoupled and inversely correlated in winter, due to the dominant effect of photoacclimation. Although Chl and C co‐varied in spring and autumn, photoacclimation modulated the Chl‐C coupling relationship as well, leading to a faster increase in C and Chl, respectively, in spring and late autumn. On daily and synoptic scales, Chl dynamics were also driven by photoacclimation to a large extent. Particularly, during a typhoon event, both cloud cover and mixed‐layer dynamics introduced fast changes in mixed‐layer light level, resulting in quick photo‐physiological responses of phytoplankton in modulating the variances of Chl. Similarly, during wintertime mixing‐restratification events associated with abrupt mixed‐layer changes, photoacclimation muted the Chl response, leading to a faster increase in C than Chl. Plain Language Summary: Although chlorophyll concentration (Chl) has been widely used as a proxy for phytoplankton biomass abundance, it is co‐determined by biomass (in unit of carbon concentration, C) and photoacclimation, the physiological mechanism of phytoplankton cells which adjusts intracellular pigment density (Chl:C) in response to ambient light and nutrients. In this study, based on three BGC‐Argo floats, we investigated how biomass and photoacclimation modulated the Chl dynamics in the mid‐latitude northwest Pacific. It was found that biomass dynamics dominated Chl dynamics in spring and summer, while photoacclimation determined Chl variations in winter leading to an inverse correlation between Chl and C. Even during the biomass‐dominated seasons, photoacclimation played an important role resulting in a slower Chl accumulation than C in spring, but a faster Chl accumulation in late autumn. Remarkably, the Chl dynamics associated with short time‐scale events such as a typhoon and wintertime mixing‐restratification events were also highly affected by photoacclimation. Key Points: Phytoplankton chlorophyll and biomass dynamics were observed in the mid‐latitude northwest Pacific using BGC‐Argo floatsDuring biomass accumulation periods, pigment density was down‐regulated, associated with faster carbon increase than chlorophyllDuring late autumn, winter and typhoon events, photoacclimation, rather than biomass, dominated the mixed‐layer chlorophyll dynamics [ABSTRACT FROM AUTHOR]

Subduction associated with mesoscale eddies is an important but difficult-to-observe process that can efficiently export carbon and oxygen to the mesopelagic zone (100–1000 dbar). Using a novel BGC-Argo dataset covering the western North Pacific (20–50 ∘ N, 120–180 ∘ E), we identified imprints of episodic subduction using anomalies in dissolved oxygen and spicity, a water mass marker. These subduction patches were present in 4.0 % (288) of the total profiles (7120) between 2008 and 2019, situated mainly in the Kuroshio Extension region between March and August (70.6 %). Roughly 31 % and 42 % of the subduction patches were identified below the annual permanent pycnocline depth (300 m vs. 450 m) in the subpolar and subtropical regions, respectively. Around half (52 %) of these episodic events injected oxygen-enriched waters below the maximum annual permanent thermocline depth (450 dbar), with >20 % occurring deeper than 600 dbar. Subduction patches were detected during winter and spring when mixed layers are deep. The oxygen inventory within these subductions is estimated to be on the order of 64 to 152 g O 2 /m 2. These mesoscale events would markedly increase oxygen ventilation as well as carbon removal in the region, both processes helping to support the nutritional and metabolic demands of mesopelagic organisms. Climate-driven patterns of increasing eddy kinetic energies in this region imply that the magnitude of these processes will grow in the future, meaning that these unexpectedly effective small-scale subduction processes need to be better constrained in global climate and biogeochemical models. [ABSTRACT FROM AUTHOR]

The Pearl River delivers a large amount of freshwater, sediments and nutrients to the northern shelf of the South China Sea (SCS). In June 2015, an anomalously strong phytoplankton bloom was captured by satellite images in the slope region of the northern SCS, which was associated with the southeastward spreading of the river plume on the shelf and a southwestward‐moving eddy along the slope. In this study, the underlying dynamics triggering the bloom was investigated using a coupled physical‐biogeochemical model. Results show that the nutrients supporting the bloom were not directly sourced from the Pearl River, but were transported locally from subsurface. The eddy cross‐slope current advected low salinity water from the Pearl River plume, which interacted with eddy edge and enhanced frontal dynamics with vertical motions. The front‐induced upwelling injected nutrients from subsurface to surface layer and stimulated phytoplankton bloom in the upper layer. Overall, the phytoplankton bloom was attributable to the interaction of freshwater plume on top and the eddy edge induced anomaly in the subsurface. These findings suggest that the eddy‐entrained freshwater could have significant biological consequences through modifying local dynamics in the plume‐influenced region. Plain Language Summary: The Pearl River plume mostly spreads on the shelf of the northern South China Sea (SCS). In June 2015, the plume was advected to the slope region by an eddy. Meanwhile, satellite captured a strong phytoplankton bloom on the slope with high chlorophyll concentration that appeared to be connected with the high chlorophyll concentration in the plume water on the shelf. With a numerical model, this study found that nitrate concentration was high at the river estuary, but it decreased quickly along the river plume on the shelf. When the plume water reached the slope region, nitrate concentration was comparable to that in surrounding waters. The advected freshwater in the plume interacted with the eddy and enhanced local front at the eddy edge, which drives vertical nutrient injection and stimulates the anomalous phytoplankton bloom in the upper layer. Key Points: An anomalous phytoplankton bloom occurred in the slope region under the influence of a mesoscale eddy and the Pearl River PlumeThe nutrients supporting the bloom were not directly sourced from the Pearl River but were injected locally from subsurfaceThe interaction of freshwater from the Pearl River and eddy edge enhances frontal dynamics facilitating nutrient transport [ABSTRACT FROM AUTHOR]

Background: Serum phosphorylated neurofilament‐heavy chain (pNF‐H) has not been longitudinally evaluated in dogs that develop progressive myelomalacia (PMM) after Type I intervertebral disc herniation (IVDH). Objectives: To determine if serum pNF‐H concentrations would predict outcome of neuroligical disease in dogs with acute, severe thoracolumbar myelopathy secondary to Type I IVDH. Animals: Thirty‐nine client‐owned dogs with thoracolumbar myelopathy secondary to IVDH. Methods: Prospective controlled cohort study. Serum was collected from dogs undergoing hemilaminectomy at multiple timepoints. Final neurological status was established at 12 months and groups were stratified accordingly. Comparisons between outcome and pNF‐H concentration at each timepoint was examined using Kruskal‐Wallis analysis of variance on ranks and receiver operator characteristics curve analysis. Results: Median serum pNF‐H concentrations were not significantly different between deep pain negative dogs that did or did not recover at any timepoint (baseline: 0.37 ng/mL [0‐0.9 ng/mL] vs 0 ng/mL [0‐0.9 ng/mL], P > 1; 24 hours: 1.25 ng/mL [0.35‐7.23 ng/mL] vs 1.53 ng/mL [0‐11.94 ng/mL], P > 1; 48 hours: 1.22 ng/mL [0.63‐6.62 ng/mL] vs 2.12 ng/mL [0‐20.72 ng/mL], P > 1; 72 hours: 2.77 ng/mL [1.33‐6.62 ng/mL] vs 16.69 ng/mL [4.02‐40.12 ng/mL], P > 1). Dogs that developed PMM had significantly higher serum pNF‐H concentrations after surgery compared to all other cohorts at 24 hours: 39.88 ng/mL (25.74‐50.68 ng/mL); P <.05 and 72 hours: 223.9 ng/mL (155.4‐263.7 ng/mL); P <.05. A serum pNF‐H concentration ≥31.39 ng/mL was 83.33% sensitive and 100% specific for identifying PMM in this cohort. Conclusions and Clinical Importance: Serum pNF‐H is a promising biomarker for antemortem diagnosis of PMM in dogs with acute, severe thoracolumbar myelopathy secondary to Type I IVDH. [ABSTRACT FROM AUTHOR]

Background: Clinical features, treatment, and outcome of opportunistic infections with Rasamsonia spp., a nonpigmented filamentous mold, are not well documented in dogs. Objectives: Describe clinical, radiographic, pathologic features, and outcome of dogs with disseminated Rasamsonia species complex infections. Animals: Eight client‐owned dogs. Methods: Retrospective case series. Medical records were reviewed to describe signalment, history, clinicopathologic and imaging findings, microbiologic and immunologic results, cyto‐ and histopathologic diagnoses, treatment, and outcome. Results: Presenting complaints were nonspecific with anorexia (n = 5) and back pain (n = 4) most common. Five dogs were German Shepherd dogs. Six dogs had multifocal discospondylitis and 2 had pleural effusion. Six dogs had Rasamsonia piperina and 2 had Rasamsonia argillacea infections with isolates identified using DNA sequencing. Rasamsonia spp. were isolated by urine culture in 5 of 7 dogs. Five of 6 dogs had positive serum Aspergillus galactomannan antigen enzyme immunoassay (EIA) results. Median survival time was 82 days, and 317 days for dogs that survived to discharge. Four died during initial hospitalization (median survival, 6 days). All isolates had low minimum effective concentrations (MECs) to echinocandins with variable minimum inhibitory concentrations (MICs) for azole antifungal drugs. Conclusions and Clinical Importance: Rasamsonia spp. infections in dogs are associated with multisystemic disease involving the vertebral column, central nervous system, kidneys, spleen, lymph nodes, lungs, and heart. The infection shares clinical features with other systemic mold infections and can be misidentified when using phenotypical microbiologic methods. Molecular techniques are required to identify the organism and guide appropriate antifungal treatment. [ABSTRACT FROM AUTHOR]

The impact of atmospheric deposition on deep‐ocean carbon export in the subtropical Northwest Pacific remains poorly evaluated. Using sediment trap data and a newly improved biogeochemical model, we show that iron deposition in winter and spring and nitrogen deposition in summer and fall are important drivers for the seasonal variability of deep‐ocean particulate organic carbon (POC) export flux. Nitrogen deposition can stimulate pico‐plankton growth in summer and fall, which leads to increases of microzooplankton and mesozooplankton. The increase of mesozooplankton exerts higher grazing pressure on diatoms in winter and early spring, which then reduces deep‐ocean POC export due to the reduction of ballasting mineral of opal. Iron deposition only affects the region in winter and spring when nitrogen is not a limiting factor for phytoplankton growth; and it can increase deep‐ocean POC export by stimulating diatom growth and opal production. Plain Language Summary: Atmospheric deposition is known to affect biogeochemistry in the upper ocean, while how it impacts carbon export to the deep ocean remains largely unknown. To evaluate the role of atmospheric deposition in deep‐ocean carbon export, this research combined in‐situ measurements from a moored sediment trap located at 4810 m and a newly improved biogeochemical model in the subtropical Northwest Pacific. We found that iron deposition increased deep‐ocean POC export, while nitrogen deposition decreased POC export in winter and spring. Seasonal change of phytoplankton community structure was shown to be the driving mechanism for the opposite response of POC export to nitrogen and iron depositions. Key Points: Strong seasonal variability of deep‐ocean particulate organic carbon (POC) export flux was found and simulated in the subtropical Northwest PacificAtmospheric iron deposition increases deep‐ocean POC export, while nitrogen deposition decreases POC export in winter and springSeasonal change of phytoplankton community structure causes the opposite response of deep‐ocean POC export to nitrogen and iron depositions [ABSTRACT FROM AUTHOR]

Typhoons are assumed to stimulate primary ocean production through the upward mixing of nutrients into the ocean surface. This assumption is based largely on observations of increased surface chlorophyll concentrations following the passage of typhoons. This surface chlorophyll enhancement, occasionally detected by satellites, is often undetected due to intense cloud coverage. Daily data from a BGC-Argo profiling float revealed the upper-ocean response to Typhoon Trami in the northwest Pacific Ocean. Temperature and chlorophyll changed rapidly, with a significant drop in sea surface temperature and a surge in surface chlorophyll associated with strong vertical mixing, which was only partially captured by satellite observations. However, no net increase in vertically integrated chlorophyll was observed during Typhoon Trami or in its wake. In contrast to the prevailing dogma, the result shows that typhoons likely have a limited effect on net primary ocean production. Observed surface chlorophyll enhancements during and immediately following typhoons in tropical and subtropical waters are more likely to be associated with surface entrainment of deep chlorophyll maxima. Moreover, the findings demonstrate that remote sensing data alone can overestimate the impact of storms on primary production in all oceans. Full understanding of the impact of storms on upper-ocean productivity can only be achieved with ocean-observing robots dedicated to high-resolution temporal sampling in the path of storms. [ABSTRACT FROM AUTHOR]

It has been suggested that the intraseasonal sea surface temperature (SST) variability in the tropical oceans can be amplified by the diurnal cycle of SST (dSST). Here, by analyzing the global tropical moored buoy array for the first time, we find that the intraseasonal SST variability is indeed amplified by the dSST in most of the tropical oceans, especially in the Indo‐Pacific warm pool, but weakened in the equatorial cold tongues of the Pacific and Atlantic Oceans. Such a divergent response is associated with the difference in atmosphere‐ocean interaction processes over these two regions. In the warm pool region, SST responds to the intraseasonal atmospheric variability, resulting in in‐phase intraseasonal fluctuations between SST and dSST that amplify the intraseasonal SST variability. However, in the cold tongue region, SST drives the atmospheric changes, which leads to out‐of‐phase intraseasonal fluctuations between SST and dSST and thus the inhibition of the intraseasonal SST variability. Plain Language Summary: The diurnal cycle is a fundamental timescale in the climate system, which has important nonlinear impacts on the variability on longer timescales. Previous studies have suggested that the diurnal cycle of sea surface temperature (SST) amplifies the SST variability on intraseasonal timescales of 20–90 days in the tropical region. By analyzing ocean temperature measurements from moored buoys located in the global tropical oceans, we find that the aforementioned amplification effect does exist in most of the tropical oceans, however, the diurnal cycle of SST weakens the intraseasonal SST variability in the equatorial eastern Pacific and Atlantic Oceans. Such contrasting results are associated with the different interaction processes between the atmosphere and the ocean over these regions. This is the first report of the inhibition effect, adding a new insight into the impact of the diurnal cycle of SST on intraseasonal SST variability. Key Points: The rectification of the intraseasonal sea surface temperature (SST) variability by the SST diurnal cycle is revealed by the global tropical moored buoy arrayThe intraseasonal SST variability is enhanced by the diurnal cycle in the Indo‐Pacific warm pool but weakened in the equatorial cold tonguesThese divergent responses are associated with the difference in atmosphere‐ocean interaction processes over these two regions [ABSTRACT FROM AUTHOR]

Key Points: Synoptic‐scale winter blooms and mixed‐layer pump events were observed by a BGC‐Argo float in the midlatitude Northwest Pacific OceanThe repetitive mixed‐layer pump episodes generated a very high particulate organic carbon export of ~110 mg C m−2 day−1 in wintertimeThe current BGC‐Argo protocols captured only 20%, or entirely missed, substantial pulsed carbon export driven by mixed‐layer pump events The winter‐ and spring‐time mixed‐layer pump (MLP) significantly augments the global carbon transport from the surface mixed layer to deeper waters when ephemeral surface phytoplankton blooms are repeatedly mixed to depth. Exploiting unusual 190 + daily BGC‐Argo profiling measurements within a recirculation gyre, we show repetitive MLP episodes generating a January–March averaged particulate organic carbon (POC) export of ~110 mg C m−2 day−1 in the midlatitude (31°N) Northwest Pacific. Subsampling this dataset on a 5‐ or 10‐day cycle yielded an order of magnitude less export, or even totally missed all the MLP events. The evidence here supports the need for new strategies if the BGC‐Argo program is to adequately quantify ocean carbon cycling and its effects on biological systems. We propose that a handful of floats be tasked with daily profiling, and machine learning strategies be used to link these data with satellite derived measurements to estimate the synoptic‐scale MLP export. Plain Language Summary: The Biogeochemical‐Argo program (BGC‐Argo) is an essential tool for quantifying carbon export from surface waters to the ocean interior, which is critical for understanding and forecasting changes in atmospheric CO2. Using novel, high‐frequency (1‐day cycle during 9‐ month period) BGC‐Argo data, we estimated the carbon export in the midlatitude Northwest Pacific Ocean stemming from unexpectedly continuous mixed‐layer pump (MLP) events. Such events occur when wintertime phytoplankton blooms developed during calm wind periods then are injected to depth by storms. This process generated remarkably high carbon export over winter, with values ranging from 18% to 30% of that from the massive North Atlantic spring bloom. These events, however, are largely (80%) or entirely missed using the longer standard float cycling intervals (5–10 days) accepted by the BGC‐Argo program. The findings here suggest that some high‐frequency BGC‐Argo observations are necessary for more accurately estimating the global carbon export. [ABSTRACT FROM AUTHOR]

Typhoons are assumed to stimulate ocean primary production through the upward mixing of nutrients into the surface ocean, based largely on observations of increased surface chlorophyll concentrations following the passage of typhoons. This surface chlorophyll enhancement, seen on occasion by satellites, more often is undetected due to intense cloud coverage. Daily data from a BGC-Argo profiling float revealed the upper-ocean response to Typhoon Trami in the Northwest Pacific Ocean. Temperature and chlorophyll changed rapidly, with a significant drop in sea surface temperature and surge in surface chlorophyll associated with strong vertical mixing, which was only partially captured by satellite observations. However, no net increase in vertically integrated chlorophyll was observed during Typhoon Trami or in its wake. Contrary to the prevailing dogma, the results show that typhoons likely have limited effect on net ocean primary production. Observed surface chlorophyll enhancements during and immediately following typhoons in tropical and subtropical waters are more likely associated with surface entrainment of deep chlorophyll maxima. Moreover, the findings demonstrate that remote sensing data alone can overestimate the impact of storms on primary production in all oceans. Full understanding of the impact of storms on upper ocean productivity can only be achieved with ocean observing robots dedicated to high-resolution temporal sampling in the path of storms. [ABSTRACT FROM AUTHOR]

The North Pacific Subtropical Gyre (NPSG) is an oligotrophic environment where a number of mesoscale eddies occur. With continuous measurements from Biogeochemical‐Argo (BGC‐Argo) floats, we showed that mesoscale eddies can significantly affect the subsurface chlorophyll maximum (SCM) and subsurface biogenic particles. Different responses of the SCM to the cyclonic and anticyclonic eddies and those between the eddy core and edge region were revealed by combining the results from tracked eddies. The variations in the SCM and subsurface particles were further shown to be statistically linked with changes in the dissolved oxygen in the upper oxygen minimum layer. Such an eddy‐induced oxygen change in the central gyre is unresolved in global‐scale coupled models but can contribute to the oxygen variability in oligotrophic environments. Key Points: Physical‐biogeochemical properties of mesoscale eddies were measured by BGC‐Argo floats in the NPSGMesoscale eddy changes SCM, but its correlation with surface chlorophyll is not significantChanges in SCM lead to variations of the DO concentration in the upper oxygen minimum layer [ABSTRACT FROM AUTHOR]

Satellite remote sensing and numerical models are widely used to estimate large-scale variations in ocean carbon export, but the relationship between export efficiency (e-ratio) of sinking organic carbon out of the surface ocean and its drivers remains poorly understood, especially in the Southern Ocean. Here, we assess the effects of temperature and primary productivity on e-ratio by combining particulate organic carbon export flux from in situ measurements during 1997–2013, environmental parameters from satellite products, and outputs from ocean biogeochemical models in the Southern Ocean. Results show that "High Productivity Low E-ratio" (HPLE) is a common phenomenon in the Subantarctic Zone and the Polar Frontal Zone, but not the Antarctic Zone. The e-ratio shows little dependence on temperature below 6 °C. Our results support the hypothesis that the HPLE phenomenon is due to the large contribution of non-sinking organic carbon. Both temperature and ballast minerals play less important roles in controlling e-ratio than ecosystem structure at low temperatures. These findings suggest that non-sinking organic carbon, ecosystem structure, and region-specific parameterizations of e-ratio are key factors to quantify the carbon export in the Southern Ocean. [ABSTRACT FROM AUTHOR]

San Francisco Bay (SFB) is a complex ecosystem that has been heavily impacted by human activities. It has experienced strong year-to-year variations in physical, chemical, and biological conditions, due to both natural climate variation and human activities. There is a need to investigate this long-term variation, with a focus on management practices and needs. The study aims to construct a coupled hydrodynamic and ecosystem model SCHISM/CoSiNE, to investigate interannual variability of chlorophyll and nutrient dynamics in SFB over the 10-year period of 2005–2014. The coupled SCHISM/CoSiNE model captures the long-term observations well. It shows that high chlorophyll concentrations in South Bay persist during warm months, while chlorophyll in North Bay is low and has strong interannual variation. Nutrient concentrations are higher in North Bay where large river outflow influences their distribution and interannual variation, and in lower South Bay. The model results show that phytoplankton blooms in Suisun Bay tend to occur when flow rates are between 100 and 250 m3/s and ammonium concentration is in the range of 1–2 mmol/m3. Model sensitivity experiments show that benthic grazing can potentially reduce phytoplankton biomass, and its effect on chlorophyll concentration is modulated by river outflow. We demonstrate the potential of this open-source model for exploring water quality conditions and options for river flow management of SFB. [ABSTRACT FROM AUTHOR]

Satellite observations of sea surface temperature (SST) show that SST in 2004, 2006, and 2016 broke the previous record in the Yellow and East China Seas (YECS). The underlying cause of the record‐breaking SSTs in the YECS is still under debate. Our analysis results demonstrate that enhanced solar radiation and weakened wind, due to a high‐pressure system over the YECS splitting from the western Pacific subtropical high, were mainly responsible for the record‐breaking SSTs in these 3 years. The enhanced solar radiation and weakened wind both depressed oceanic turbulent mixing, and more heat was concentrated in a shallower mixed layer, inducing an anomalous SST rise and resulting in the record‐breaking SSTs. Key Points: SST in 2004, 2006, and 2016 broke the previous record of satellite observations in the Yellow and East China SeasThe record‐breaking SSTs in these 3 years were mainly attributed to enhanced solar radiation and weakened windEnhanced solar radiation and weakened wind were associated with a high‐pressure system splitting from the Pacific subtropical high [ABSTRACT FROM AUTHOR]

In this study, we isolated seven strains (termed BY1–7) from polluted soil at an oil station and evaluated their abilities to degrade total petroleum hydrocarbons (TPHs). Following 16 rRNA sequence analysis, the strains were identified as belonging to the genera Bacillus, Acinetobacter, Sphingobium, Rhodococcus, and Pseudomonas, respectively. Growth characterization studies indicated that the optimal growth conditions for the majority of the strains was at 30 °C, with a pH value of approximately 7. Under these conditions, the strains showed a high TPH removal efficiency (50%) after incubation in beef extract peptone medium for seven days. Additionally, we investigated the effect of different growth media on growth impact factors that could potentially affect the strains' biodegradation rates. Our results suggest a potential application for these strains to facilitate the biodegradation of TPH-contaminated soil. [ABSTRACT FROM AUTHOR]

The Gulf Stream (GS) transports a massive amount of heat northward to high latitudes and releases sensible and latent heat to the atmosphere, playing an important role in the North Atlantic and European climate change. The change trends of the GS transport and pathway are still uncertain to date. Our analyses of altimeter observations from 1993 to 2016 indicate that the linear trends in surface maximum speed, transport, and latitudinal location of the GS are significant east of 61° W at the 95% level while they are small and not significant between 72° W and 61° W. The weakening trend of the GS during the period from 1993 to 2016 is accompanied with a southward-shifting path, which is associated with the decline of the North Atlantic Oscillation (NAO) and possibly reduction in the Atlantic meridional overturning circulation (AMOC). [ABSTRACT FROM AUTHOR]

Geosynthetics have been widely used in the construction of reinforced soil structures and yet the reinforcing mechanisms of geosynthetics have not been fully understood. Eight biaxial compression model tests of geosynthetic-reinforced soil (GRS) were conducted in this study under a plane strain condition to investigate the reinforcing mechanisms of geosynthetics. Membrane was used as reinforcement material and aluminum rods were used to simulate the granular backfill soil. Three influencing factors were considered in the model tests including reinforcement spacing, reinforcement stiffness, and gradation of backfill soil. This study also conducted a numerical analysis using a discrete element method (DEM) model. The DEM model was calibrated and verified by geosynthetic tensile test, angle of repose test, biaxial test, and model test results of the GRS masses. The piecewise linear model was used in the numerical model to simulate the nonlinear characteristics of the geosynthetic under tensile load. A parametric study was conducted to obtain further detailed insights into the reinforcing mechanisms of geosynthetics. Results of the model tests and the numerical simulations indicated that reinforcement spacing had strong effects on the behavior of the GRS mass. The dilation of the backfill soil was suppressed by reinforcement and the suppression was enhanced by increasing reinforcement stiffness and reducing reinforcement spacing. The reinforcement spacing played a more important role in the behavior of the GRS than the reinforcement stiffness. Geosynthetics reinforcement could restrain the development of vertical settlements along the height of the GRS mass. In addition, the geosynthetic reinforcement had a function of dispersing vertical applied pressure and the stress induced by loading was more uniformly distributed in the GRS mass as compared with unreinforced cases. Increasing reinforcement stiffness had little effect to improve the dispersion function of geosynthetics. The reinforcing effects in the GRS mass backfilled with soil of low strength were more significant compared to that in the GRS mass backfilled with soil of high strength. [ABSTRACT FROM AUTHOR]

Fourteen years (September 2002 to August 2016) of high-resolution satellite observations of sea surface temperature (SST) data are used to describe the frontal pattern and frontogenesis on the southeastern continental shelf of Brazil. The daily SST fronts are obtained using an edge-detection algorithm, and the monthly frontal probability (FP) is subsequently calculated. High SST FPs are mainly distributed along the coast and decrease with distance from the coastline. The results from empirical orthogonal function (EOF) decompositions reveal strong seasonal variability of the coastal SST FP with maximum (minimum) in the astral summer (winter). Wind plays an important role in driving the frontal activities, and high FPs are accompanied by strong alongshore wind stress and wind stress curl. This is particularly true during the summer, when the total transport induced by the alongshore component of upwelling-favorable winds and the wind stress curl reaches the annual maximum. The fronts are influenced by multiple factors other than wind forcing, such as the orientation of the coastline, the seafloor topography, and the meandering of the Brazil Current. As a result, there is a slight difference between the seasonality of the SST fronts and the wind, and their relationship was varying with spatial locations. The impact of the air-sea interaction is further investigated in the frontal zone, and large coupling coefficients are found between the crosswind (downwind) SST gradients and the wind stress curl (divergence). The analysis of the SST fronts and wind leads to a better understanding of the dynamics and frontogenesis off the southeastern continental shelf of Brazil, and the results can be used to further understand the air-sea coupling process at regional level. [ABSTRACT FROM AUTHOR]

Mesoscale eddies in the oceans are known to modify the nutrient supply, stimulate phytoplankton growth, and significantly affect carbon fixation. Submesoscale processes associated with mesoscale eddies have been suggested to induce even stronger variability in phytoplankton dynamics; however, their large‐scale impact has not been quantitatively evaluated in the global ocean. By combining multiple satellite products to resolve both mesoscale and submesoscale dynamic regimes, we evaluated their contributions to high sea surface chlorophyll. Our results reveal that the dominant dynamics associated with high chlorophyll in different gyres are not the same and can vary from the mesoscale to the submesoscale. In subtropical gyres worldwide, the contribution of submesoscale structures around mesoscale eddies to high chlorophyll is comparable to that of mesoscale eddies (34.1% versus 30.8%). These results extend our current understanding of the impacts of eddies on biogeochemical processes and may have important implications for the global carbon cycle. Plain Language Summary: Subtropical gyres are characterized as being nutrient‐depleted at the surface, and mesoscale and submesoscale processes are the key physical activities facilitating the transport of nutrients into the upper ocean. Submesoscale dynamics lead to more intense vertical motion and the enhanced upward transport of nutrients, thereby triggering stronger phytoplankton blooms. Evaluating the roles of submesoscale and mesoscale processes in marine biology is important for understanding phytoplankton dynamics and the global carbon cycle. However, the small spatial and temporal scales of submesoscale processes are not resolvable in most satellite data. In this study, we develop a new method using sea level anomaly (SLA) and finite‐size Lyapunov exponent (FSLE) data to quantify the impacts of submesoscale and mesoscale processes on satellite‐derived chlorophyll in the interiors of subtropical gyres worldwide. Our results show that the contribution of submesoscale processes to high chlorophyll is comparable to that of mesoscale eddies, highlighting the need to address fine‐scale physical‐biogeochemical interactions in subtropical gyres around the globe. Key Points: A new method for quantifying mesoscale and submesoscale contributions to high sea surface chlorophyll concentrations is developedThe contribution of submesoscale processes to high chlorophyll is comparable to that of mesoscale eddies in subtropical gyres worldwideThe dominant dynamics contributing to high chlorophyll concentrations vary from gyre to gyre [ABSTRACT FROM AUTHOR]

The month‐to‐month variation of the winter South China Sea (SCS) western boundary current (WBC) along the western slope is examined using drifter observations, satellite altimetry data, and an ocean reanalysis. The most surprising phenomenon is that the WBC velocity at the sea surface reaches the maxima in November–December, which cannot be explained by wind forcing and Kuroshio intrusion alone. Analysis results demonstrate that buoyancy effect should be considered to explain the month‐to‐month variation besides wind‐Kuroshio effects. In winter, cold‐and‐salty advection by the WBC from the north decreases/reverses the zonal density gradient in the seasonal pycnocline induced by wind forcing and Kuroshio intrusion and therefore weakens wind‐Kuroshio‐induced WBC. Buoyancy effect on the winter SCS WBC is opposite to wind‐Kuroshio effects. In addition, buoyancy effect reaches the maximum in January, which is concurrent with wind‐Kuroshio effects. As a result of their competition, the zonal density gradient in the seasonal pycnocline is maximum in November–December, resulting in the maximum surface velocity along the western slope occurring in November‐December. This study demonstrates the importance of buoyancy forcing to the winter SCS WBC. Key Points: Surface velocity of western boundary current reaches the maxima in November–December, which cannot be explained by wind‐Kuroshio aloneBuoyancy weakens western boundary current by decreasing the zonal density gradient in the pycnocline, which is opposite to wind‐KuroshioAs a result of the competition, the zonal density gradient in the pycnocline is maximum in November–December, causing the maximum velocity [ABSTRACT FROM AUTHOR]

Variability of oceanic salinity, an indicator of the global hydrological cycle, plays an important role in the basin-scale ocean circulation. In this study, interannual to decadal variability of salinity in the upper layer of the Indian Ocean is investigated using Argo observations since 2004 and data assimilating model outputs (1992–2015). The southeastern Indian Ocean shows the strongest interannual to decadal variability of upper-ocean salinity in the Indian Ocean. Westward propagation of salinity anomalies along isopycnal surfaces is detected in the southern Indian Ocean and attributed to zonal salinity advection anomalies associated with the Indonesian Throughflow and the South Equatorial Current. Composite and salinity budget analyses show that horizontal advection is a major contributor to the interannual to decadal salinity variability of the southern Indian Ocean, and the local air–sea freshwater flux plays a secondary role. The Pacific decadal oscillation (PDO) and El Niño–Southern Oscillation (ENSO) modulate the salinity variability in the southeastern Indian Ocean, with low salinity anomalies occurring during the negative phases of the PDO and ENSO and high salinity anomalies during their positive phases. The Indonesian Throughflow plays an essential role in transmitting the PDO- and ENSO-related salinity signals into the Indian Ocean. A statistical model is proposed based on the PDO index, which successfully predicts the southeastern Indian Ocean salinity variability with a lead time of 10 months. [ABSTRACT FROM AUTHOR]

A significant strong, warm "Blob" (a large circular water body with a positive ocean temperature anomaly) appeared in the Northeast Pacific (NEP) in the boreal winter of 2013–2014, which induced many extreme climate events in the US and Canada. In this study, analyses of the temperature and salinity anomaly variations from the Array for Real-time Geostrophic Oceanography (Argo) data provided insights into the formation of the warm "Blob" over the NEP. The early negative salinity anomaly dominantly contributed to the shallower mixed layer depth (MLD) in the NEP during the period of 2012–2013. Then, the shallower mixed layer trapped more heat in the upper water column and resulted in a warmer sea surface temperature (SST), which enhanced the warm "Blob". The salinity variability contributed to approximately 60% of the shallowing MLD related to the warm "Blob". The salinity anomaly in the warm "Blob" region resulted from a combination of both local and nonlocal effects. The freshened water at the surface played a local role in the MLD anomaly. Interestingly, the MLD anomaly was more dependent on the local subsurface salinity anomaly in the 100–150 m depth range in the NEP. The salinity anomaly in the 50–100 m depth range may be linked to the anomaly in the 100–150 m depth range by vertical advection or mixing. The salinity anomaly in the 100–150 m depth range resulted from the eastward transportation of a subducted water mass that was freshened west of the dateline, which played a nonlocal role. The results suggest that the early salinity anomaly in the NEP related to the warm "Blob" may be a precursor signal of interannual and interdecadal variabilities. [ABSTRACT FROM AUTHOR]