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The observed variations in intense geomagnetic flux lobes have a significant impact on regional geomagnetic fields, and produce unique geomagnetic characteristics. To investigate the time‐dependent effect of the Siberian flux lobe on the geomagnetic field in East Asia, we reconstructed a stacked full‐vector paleomagnetic secular variation record (since 2000 BCE) from three sediment cores collected in the Bohai Sea, China. Age models of the studied cores were established through a combination of radiocarbon 14C dating and inter‐profile correlation of mass‐normalized magnetic susceptibility. Rock magnetic results indicate that fine‐grained magnetite is the primary remanent carrier. We found that the paleomagnetic field records in the Bohai Sea correspond more closely with those from the middle latitudes, rather than the low latitudes. This was primarily attributed to the variation of the Siberian flux lobe. This study provides a better understanding of the contrasting patterns of regional geomagnetic fields in East Asia, and emphasizes the significant role played by the Siberian flux intensity lobe in shaping their formation. Plain Language Summary: The Earth's magnetic field is in a constant state of flux, both temporally and spatially, and plays a crucial role in protecting our planet from solar wind and cosmic rays. The long‐term variation of the Earth's magnetic field is closely linked with the magnetic flux patch situated at the core‐mantle boundary. However, our understanding of the evolution of magnetic flux patches has been limited by the use of short‐term instrumental data and discrete archeomagnetic data. In this paper, we reconstruct a ∼4,000‐year high‐resolution full‐vector paleomagnetic record from sediments in the Bohai Sea, China. Our findings reveal a clear contrast in the paleomagnetic variations between the middle and low latitudes of East Asia. We proposed that the Siberian flux intensity lobe likely played an important role in the observed paleomagnetic behavior discrepancy between the low‐ and mid‐latitudes of East Asia. Key Points: A multi‐decadal resolution paleomagnetic record spanning approximately 4,000 years has been derived from sediments in the Bohai Sea, ChinaThe paleomagnetic behavior differs between middle and low latitudes across East Asia, indicating the variation of the Siberian flux lobeThe disparity in inclination between the Chinese and Levantine spikes implies that these spikes arise from separate magnetic flux patches [ABSTRACT FROM AUTHOR]

The lack of suitable indicators of changes in such as sea‐level and circulation has been a major limit to paleoenvironmental and paleoceanographic investigations in continental shelf regions. This paper presents an environmental magnetic study by comparing two late‐Quaternary sediment cores (DH02 and DH03) from the outer shelf of the East China Sea (ECS). Late and early Marine Isotope Stage (MIS) 3 sediments were deposited in a prodelta under cold coastal currents and an open‐shelf with the Taiwan Warm Current and upwelling. The dominant iron‐bearing minerals of the late and early MIS 3 sediments are authigenic greigite (Fe3S4) and pyrite (FeS2), respectively, which were assumed to be formed nearly syndepositionally. The overlying sediments, however, are magnetically dominated by detrital magnetite. This pattern corresponds well to the temporal changes in sea‐level over this period. The widespread occurrence of greigite in the late MIS 3 sediments can also be used for future stratigraphic division and correlation in the ECS. Additionally, compared to microfossil assemblages, rock magnetic parameters based on greigite may be more sensitive to environmental changes on continental shelves. Furthermore, the inter‐borehole spatial comparisons imply not only a sedimentary hiatus/erosion of at least 30‐m thickness in core DH02, most probably during the Last Glacial Maximum, but also that core DH02 was in a more reductive environment than core DH03 during late MIS 3. The findings highlight the potential of authigenic greigite as an indicator of spatiotemporal changes in paleoenvironmental and paleoceanographic conditions on the continental shelf at orbital or even suborbital timescales. Plain Language Summary: Environmental and oceanographic conditions on continental shelves are vital for sedimentation processes and human settlements, but the reconstruction of their evolution is hindered by the lack of effective indicators. Recent studies have indicated that syndepositional formation of greigite, a precursor to pyrite, is highly likely in shallow‐water environments with rapid sedimentation. Here, two sediment cores meridionally traversing the outer shelf of the East China Sea were investigated. The magnetic mineral assemblage and sedimentary environment exhibited almost identical change patterns, with pyrite, greigite, and magnetite as the major magnetic minerals of the early and late Marine Isotope Stage 3, and Last Glacial Maximum/last deglacial deposits, respectively. This agreeably reflects the temporal fluctuations in sea‐level and ocean circulation. By comparing the two cores, the spatial characteristics of stratigraphy and redox conditions could be determined clearly. This study thus provides a good reference for paleoenvironmental and paleoceanographic research based on authigenic greigite in continental shelf sediments. Key Points: Greigite was further confirmed as the major magnetic mineral of the late Marine Isotope Stage 3 deposits widespread on the outer shelf of the East China SeaSpatiotemporal changes in environmental and oceanographic conditions on the continental shelf are well revealed by greigite‐based parametersAuthigenic greigite can serve as a sensitive indicator for paleoenvironmental and paleoceanographic studies in continental shelf regions [ABSTRACT FROM AUTHOR]

The carbonate clumped isotope (Δ47) thermometer has been widely used for paleoclimatic and paleo‐elevation reconstructions in sedimentary basins. Its reliable use requires that carbonates are free from later diagenetic alteration and retain their depositional Δ47 compositions, which is not always the case during the burial history of a basin. Therefore, identifying the alteration mechanisms that occurred during burial is essential for the correct interpretation of Δ47 signatures. In this study, we used the Δ47 thermometer to investigate possible carbonate alteration during burial of the Fenghuoshan Group (FHSG) in the Hoh Xil Basin, northern Tibetan Plateau, China. The Δ47 temperatures [T(Δ47)] of 30 carbonate samples through the ∼4.5 km thickness of the FHSG range from 51 to 132°C and exceed the surface temperature, implying the effects of thermal alteration on FHSG carbonates. The T(Δ47) values combined with the water‐rock exchange model, indicating that the alteration occurred under closed burial conditions at low water:rock ratios. The solid‐state reordering model fails to predict the Δ47 values, even with a modified time‐temperature history. In contrast, most measured Δ47 values are in agreement with predictions from recrystallization models. Therefore, the proposed alteration scenario is that FHSG carbonates underwent progressive microscale recrystallization during deep burial and subsequent exhumation, during which process recrystallized carbonate equilibrated with ambient burial temperature and therefore modified Δ47 values. This study highlights the potential of Δ47 thermometry and related models for evaluating the burial history and diagenesis of carbonates in sedimentary basins. Plain Language Summary: Carbonate clumped isotope composition (defined as Δ47) refers to the abundance of 13C–18O bonds in the carbonate, which is solely temperature dependent. This temperature dependence makes Δ47 a useful tool that can be used to obtain the carbonate formation temperature. However, the original Δ47 composition could be altered by either solid‐state reordering of C–O bonds or carbonate recrystallization during the burial history of sedimentary basin. Discriminating which alteration occurred during burial process is essential for the correct interpretation of Δ47 signature and the burial history. In this study, we measured Δ47 values of Fenghuoshan Group (FHSG) carbonates in the Hoh Xil Basin, northern Tibetan Plateau, China, and investigated their alteration during the burial history of FHSG by using the solid‐state reordering and recrystallization models. Our results indicate that FHSG carbonates underwent progressive microscale recrystallization during deep burial history, and the recrystallized carbonates recorded modified higher Δ47 temperatures. This study highlights the potential of Δ47 thermometry and related models for evaluating the burial history of sedimentary basins. Key Points: Clumped isotope temperatures of 51–132°C reflect thermal alteration during the burial history of the Fenghuoshan Group (FHSG)The alteration of FHSG carbonate Δ47 occurred in a late‐burial environment at a low water‐rock ratioFHSG carbonate underwent microscale recrystallization during burial and exhumation and eventually recorded high T(Δ47) [ABSTRACT FROM AUTHOR]

Much has been learned regarding orbital and millennial timescale climate changes after the onset of Northern Hemisphere glaciations (NHG) at ca. 2.7 Ma. By contrast, little is known about these variations before the NHG due to lack of high‐resolution records. Here we report first millennial resolution quantified East Asian summer monsoon (EASM) precipitation record from the north eastern Tibetan Plateau. The record supports astronomical forcing of EASM during the late Miocene, except for the period of 8.13–8.03 Ma when EASM experienced high amplitude variations at the 100‐, 20‐kyr, and suborbital bands, which is in sharp contrast with the damped astronomical forcing. Detection of strong 100‐kyr and millennial cycles during low eccentricity intervals of the warm late Miocene with ephemeral NH ice sheets cast doubt on NH ice sheet size variations as their exclusive forcing in the late Miocene and late Quaternary paleoclimatic records. Plain Language Summary: Millennial and 100‐kyr cycles in paleoclimate records are normally attributed to Northern Hemisphere ice sheet size variations. Here we present the first 1‐kyr resolution quantitative East Asian summer monsoon precipitation record from the northeastern Tibetan Plateau during the late Miocene, when Northern Hemisphere ice sheets were ephemeral. The record demonstrates strong 100‐kyr and clear millennial cycles. Detection of 100‐kyr and millennial cycles in this warm time interval cast doubt on Northern Hemisphere ice sheet size variations as their exclusive forcing in paleoclimatic records. Key Points: First 1‐kyr resolution quantitative northern China precipitation record during the late MioceneThe record reveals strong 100‐kyr and clear millennial cyclesDetection of 100‐kyr and millennial cycles in this warm interval challenges Northern Hemisphere (NH) ice sheet size variations as their exclusive forcing [ABSTRACT FROM AUTHOR]

Bt rice can control yield losses caused by lepidopteran pests but may also harm nontarget species and reduce important ecosystem services. A comprehensive data set on herbivores, natural enemies, and their interactions in Chinese rice fields was compiled. This together with an analysis of the Cry protein content in arthropods collected from Bt rice in China indicated which nontarget species are most exposed to the insecticidal protein and should be the focus of regulatory risk assessment. [ABSTRACT FROM AUTHOR]

Multiple lines of transgenic rice expressing insecticidal genes from the bacterium Bacillus thuringiensis ( Bt) have been developed in China, posing the prospect of increases in production with decreased application of pesticides. We explore the issues facing adoption of Bt rice for commercial production in China. A body of safety assessment work on Bt rice has shown that Bt rice poses a negligible risk to the environment and that Bt rice products are as safe as non- Bt control rice products as food. China has a relatively well-developed regulatory system for risk assessment and management of genetically modified ( GM) plants; however, decision-making regarding approval of commercial production has become politicized, and two Bt rice lines that otherwise were ready have not been allowed to enter the Chinese agricultural system. We predict that Chinese farmers would value the prospect of increased yield with decreased use of pesticide and would readily adopt production of Bt rice. That Bt rice lines may not be commercialized in the near future we attribute to social pressures, largely due to the low level of understanding and acceptance of GM crops by Chinese consumers. Hence, enhancing communication of GM crop science-related issues to the public is an important, unmet need. While the dynamics of each issue are particular to China, they typify those in many countries where adoption of GM crops has been not been rapid; hence, the assessment of these dynamics might inform resolution of these issues in other countries. [ABSTRACT FROM AUTHOR]

Abstract: The Huguangyan (HGY) lake, a typical maar lake in the southeast of China, is sensitive to the evolution of the Asian monsoon system, including the East Asian summer monsoon (EASM) and the Indian summer monsoon (ISM). So far, the mechanism of how magnetic properties of the HGY lake sediments respond to climate changes has not been well determined. In this study, we performed a detailed mineral-magnetic analysis on the high-resolution HGY sediments. Results revealed that finer-grained magnetite (superparamagnetic and single domain magnetite mixed with a small amount of goethite and hematite) is the dominant magnetic mineral, which is consistent with the magnetic properties of the red weathered soils collected from the catchments, but differs greatly from that of the aeolian inputs. Therefore, magnetic minerals of the HGY sediments were originated mainly from the lake catchment, rather than the wind-blown dust inputs. Considering the high tephra wall (relative elevation of 10–20m) and great precipitation, surface runoff by rainfall is interpreted as the main process to transport red soils into the lake. The magnetic records of HGY sediments revealed that the summer monsoon was enhanced at the early Holocene and then declined abruptly at the mid-late Holocene (~5.5kyr cal. BP). This pattern strongly mimics the evolution pattern of ISM, but is inconsistent with the EASM. Thus, we suggest that the magnetic records from HGY have the great potential to investigate the evolution of ISM. [Copyright &y& Elsevier]

Agricultural nonpoint source (NPS) pollution has been the most important threat to water environment quality. Understanding the spatial distribution of NPS pollution potential risk is important for taking effective measures to control and reduce NPS pollution. A Transformed-Agricultural Nonpoint Pollution Potential Index (T-APPI) model was constructed for evaluating the national NPS pollution potential risk in this study; it was also combined with remote sensing and geographic information system techniques for evaluation on the large scale and at 1 km2 spatial resolution. This model considers many factors contributing to the NPS pollution as the original APPI model, summarized as four indicators of the runoff, sediment production, chemical use and the people and animal load. These four indicators were analysed in detail at 1 km2 spatial resolution throughout China. The T-APPI model distinguished the four indicators into pollution source factors and transport process factors; it also took their relationship into consideration. The studied results showed that T-APPI is a credible and convenient method for NPS pollution potential risk evaluation. The results also indicated that the highest NPS pollution potential risk is distributed in the middle-southern Jiangsu province. Several other regions, including the North China Plain, Chengdu Basin Plain, Jianghan Plain, cultivated lands in Guangdong and Guangxi provinces, also showed serious NPS pollution potential. This study can provide a scientific reference for predicting the future NPS pollution risk throughout China and may be helpful for taking reasonable and effective measures for preventing and controlling NPS pollution. [ABSTRACT FROM PUBLISHER]

This paper studies magnetic properties and composition of granulite-facies rocks of both the Neogene and Archean continental lower crust in the Neogene xenolith-bearing Hannuoba(汉诺坝) alkaline basalt and the exposed lower crustal section in the Archean Huai'an(淮安) terrain (Wayaokou (瓦窑口)-Manjinggou(蔓菁沟 profile), the northern North China Craton. It provides a unique opportunity for a comparative study of magnetic properties and composition of both the Archean and Neogene continental lower crust. We measure magnetic parameters (susceptibility κ and magnetic hysteresis parameters, such as saturation magnetization J, saturation isothermal remanent magnetization J, and intrinsic coercivity H) of eleven Hannuoba lower crustal xenoliths and nine terrain granulites from the Archean Huai'an terrain. Results indicate that the average values of κ, J and J of Archean granulites are 4 122×10 SI, 523.1 A/m and 74.9 A/m, respectively, which are generally higher than those of granulite-facies xenoliths (1 657×10 SI, 163.9 A/m and 41.9 A/m, respectively). These two types of granulites contain ilmenite, (titano) magnetite, minor hematite and some 'magnetic silicates' (clinopyroxene, plagioclase and biotite). The Mg-rich ilmenite in granulite-facies xenolith is relatively higher than that in terrain granulites. We observe a more evolved character as higher magnetic as well as lower Sr/Nd, Cr/Nd, Ni/Nd, Co/Nd and V/Nd ratios in terrain granulites. These differences in magnetic characteristics reflect their different origins and evolutions. The high magnetization of granulites in the Huai'an terrain represents magnetic properties of the Archean continental lower crust, and low magnetization of granulite-facies xenoliths represents magnetic properties of the Cenozoic lower crusts in the northern North China Craton. [ABSTRACT FROM AUTHOR]

SUMMARY A composite Holocene sediment profile ∼5 m in length, constrained by both radiocarbon dating and magnetic susceptibility based correlation, was obtained from three Livingstone piston cores collected in ∼10-m water depth in the Huguangyan (HGY) maar lake, southern China. The homogeneous silty clay indicates stable and continuous deposition. The dominant magnetic carrier is magnetite in the pseudo-single-domain grain size range and thus is suitable for recording palaeomagnetic secular variations (PSV). Results show that the HGY PSV curves can be correlated faithfully to the counterparts at a regional scale. Therefore, the PSV data is a potential tool for stratigraphic correlation and for further refining the chronological framework of lake sediment sequences from Southern China. Further comparison of the HGY PSV records with the coeval European and North American counterparts confirms the existence of strong permanent magnetic flux lobes at the core-mantle boundary. The discrepancy in amplitude and out-phase pattern among the different regional records may be ascribed to the evolution of the magnetic flux lobes. [ABSTRACT FROM AUTHOR]

SUMMARY Widely distributed haematite-bearing red beds are an important source of palaeomagnetic field records. However, unresolved issues regarding remagnetization and inclination shallowing in red beds have questioned the reliability of the palaeomagnetic results obtained from such materials. In this study, we investigated the remagnetization mechanism in red beds from Lower Triassic sandstones in Yunnan Province, southwestern China. Our results indicate that the characteristic remanent magnetizations (ChRMs) of most samples (112/125) are dominated by only one component at temperatures 80-660 °C, with a mean direction of D/ I= 0.9/46.6° ( k= 440.2, α95= 2.1°). The corresponding geomagnetic pole is 89.1°N, 331.7°E ( k= 338.2, A95= 2.4°). This coincides with the present geomagnetic field, which is a strong indication that these ChRMs are remagnetized. Combined rock magnetic and microscope investigations reveal that the remagnetization is due to the acquisition of a chemical remanent magnetization (CRM) carried by authigenic maghemite and haematite. Despite the widespread remagnetization, about 7 per cent of the studied samples still record a magnetization that we consider to be primary that was isolated at high temperatures 610-660 °C, with a mean direction of D/ I= 213.3/18.6° ( k= 16.0, α95= 11.7°). We propose that the CRM overprinting is controlled by the overlapping degree of the unblocking temperature between the CRM carried by the authigenic haematite and the primary remanent magnetization carried by the detrital haematite. Our results further suggest that microscope investigation, rock magnetic proxies for the haematite concentration and susceptibility-temperature curves are useful methods for pre-selecting samples suitable for isolating the primary remanence at this region. The linkage among the palaeomagnetic results, rock magnetic proxies and CRM remagnetization mechanism could be extended to other studies, although the detailed proxy would be different due to specific overprint process. [ABSTRACT FROM AUTHOR]

Abstract: It is commonly accepted that the climate records in Chinese loess can be correlated well with that in marine sediments. However, discrepancies for the stratigraphic position of paleomagnetic polarity reversal boundary seriously restrict an accurate teleconnection between these two archives. For example, the exact stratigraphic position of the whole Matuyama–Brunhes (MB) transitional polarity zone remains uncertain in Chinese loess. In this study, an accurate transitional zone of the MB reversal from the Mangshan profile, southeast margin of the Chinese Loess Plateau (CLP), was statistically determined using multiple subsets of parallel samples. By integrating results from the central CLP, the whole MB transitional zone is consistently located across the pedostratigraphic and climatostratigraphic transitional zones between S8 and L8 over a wide region of the CLP. This conclusion further supports that the paleosol unit S8 should be teleconnected to the marine oxygen isotope stage 19 rather than 21, and thus unambiguously supplies an accurate age control in constructing a new loess time scale. [ABSTRACT FROM AUTHOR]

Abstract: New palaeomagnetic and 40Ar/39Ar dating was carried out on the volcanic rocks and interbedded fossil-bearing lake sediments at the Sihetun section (northeast China) to determine the duration of deposition of the lacustrine sediments. The 40Ar/39Ar ages of the lower and upper volcanic rocks near the lava-sediment contacts are respectively 125.7±2.6Ma and 124.2±2.5Ma, which is in good agreement with a previously reported age of tuffs in the lake deposits. This is further supported by a normal palaeomagnetic polarity recorded by the whole lacustrine interval. With these palaeomagnetic investigations and new age controls, we conclude that the whole lacustrine interval at Sihetun was deposited within the normal polarity chron M3n (marine anomaly) during the Early Cretaceous. The possibly volcanic-associated ancient lake may have existed for a relatively short duration of less than 0.7myr, assuming the M3n chron age to be between 124.72–124.04Ma. [Copyright &y& Elsevier]

It has been proposed that paleoclimatic changes and tectonic events strongly affect hominoid evolution. The Zhupeng section at Yuanmou Basin, southwestern China, with the hominoid-bearing fluvial-lacustrine sediments, is an ideal natural laboratory to test this hypothesis. This study provided an integrated magnetic study, including low-frequency susceptibility, the anisotropy of magnetic susceptibility, temperature-dependent susceptibility, hysteresis loops, isothermal remanent magnetization, and anhysteretic remanent magnetization, on samples from the Baozidongqing section at Zhupeng. Results show that the dominant magnetic carrier is hematite, with minor amount of magnetite. Both the composition and concentration of magnetic minerals strongly correlate with the lithostratigraphy. At least eight short-term events defined by higher concentrations of magnetite were identified. These short events reflect that the subtropical dry-hot climate is similar to today's climate. Basing on the lithostratigraphic and rock magnetic results, we suggest that Yuanmou Basin was in a steady deposition environment from about 11 to 7 Ma, which is characterized by alternating of long-term torrid-humid climate and short-term dry-hot climate. Our study provides invaluable environment information for understanding the climate shift and the relationship between paleoenvironment and hominoid evolution in southwestern China during late Miocene. [ABSTRACT FROM AUTHOR]

Abstract: Low-field magnetic susceptibility has been widely used to determine the pedostratigraphy of the Chinese loess/paleosol sequences. However, uncertainties remain in correlating between the loess magnetic susceptibility and the marine oxygen isotope records because susceptibility variations are affected by both global and local paleoclimatic changes. To provide a more sound paleoclimatic interpretation of magnetic susceptibility variations, age models across Marine Oxygen Isotope Stage (MIS) 5 for the Jiuzhoutai (JZT) and Yuanbao (YB) sections, western Chinese Loess Plateau, were constructed through an integrated approach by linking the major pedostratigraphic boundaries of the loess profiles to the SPECMAP oxygen isotope curve, and by correlating relative magnetic paleointensity records with both the SINT800 global paleointensity stack from marine sediments and 36Cl records from the GRIP ice core. Results indicate good correlation of SIRM60mT (a residual remanence of saturation isothermal remanent magnetization after a 60mT alternating field demagnetization) variations between these two sites, which agree well with fluctuations in subtropical Atlantic sea surface temperatures. All cooling events recorded by ice-core and Atlantic marine sediments within MIS5 have counterparts in SIRM60mT. SIRM60mT is partially controlled by the degree of low-temperature oxidation, which is strongly temperature dependent. However, strong pedogenesis can decrease SIRM60mT due to further oxidation of partially oxidized magnetites above some critical points. Therefore, we propose that SIRM60mT is best suited to record paleotemperature changes in loess profiles from the western Chinese Loess Plateau, where pedogenesis is the weakest. Furthermore, by inter-profile correlation between the YB and JZT sections, we note that the seemingly uniform sub-paleosol unit with a broad susceptibility peak (previously assigned to MIS5c) between ∼34.4 and ∼37.4m in the YB profile actually consists of two independent units (lower part of S1L1/MIS5b and S1S2/MIS5c). This indicates that susceptibility values can be strongly affected by local factors (e.g., mainly precipitation). Therefore, beside the simplistic traditional paleoclimatic interpretation of variations in loess susceptibility involving only cold/dry and warm/humid scenarios, cold/humid and warm/dry scenarios should also be considered. [Copyright &y& Elsevier]

We compare new anisotropy of magnetic susceptibility (AMS) data with previously-determined paleoclimatically sensitive parameters for a loess profile at Lingtai, central Loess Plateau, China, to unravel factors that control loess AMS. Magnetic lineations are clustered along NE–SW and NW–SE orientations during cold and warm periods, respectively, which probably corresponded to paleowind directions of both winter and summer monsoons. Anomalously steep magnetic foliations coincidentally occur at the paleoclimatic stage boundaries, indicating sediment disturbance. Lineation strength appears to be sensitive to millennial-scale rapid paleoclimatic fluctuations. Generally, the winter monsoon produces a lower degree of lineation than the summer monsoon. Furthermore, by studying lineation subsets for the cold and warm periods, we find that the cold-interval lineation strengths co-vary with grain size over the last ∼70 ka. During the last interglacial (about 74–128 ka), the lineation and declination of the susceptibility maximum (Dec-Kmax) are sensitive to rapid fluctuations in winter and summer monsoons. Long-term trends of magnetic foliation and anisotropy degree replicate grain size variations, with superimposed short-term peaks related to post-depositional compaction, as suggested by density. The AMS shape parameter (T) indicates oblate fabrics. These new findings will not only improve our understandings of loess AMS, but also expand the possibilities of paleoclimatic studies in the Chinese loess. [Copyright &y& Elsevier]

This paper proposes a new method to distinguish between interglacial deposits and pedogenically-overprinted glacial loess based on the concentration variations of coarse-grained aeolian (magnetically pseudo-single domain and multidomain) magnetite. We apply the method to a sequence from the upper part of the loess unit L2 (marine isotope stage MIS 6) to the sub-loess unit S1L2 (MIS 5d) at the YuanBo (YB) section in the Chinese Loess Plateau. The method is based on the differences in low temperature properties between the coarse-grained (multidomain and pseudo-single domain) detrital magnetite and the pedogenic magnetic particles including superparamagnetic (SP) particles and relatively larger (>SP) maghemite particles. The former is characterized by a crystallographic Verwey transition around 120 K. In contrast, the magnetization of the latter continuously decreases in intensity with increasing temperatures. The method involves two steps: (1) calculating the first-derivative of the low temperature thermal demagnetization of the saturated isothermal remanent magnetization acquired at 20 K (LT-SIRM), which enhances the behaviour related to the Verwey transition, and (2) fitting a third-order polynomial background to the data between both 50–70 and 150–300 K, and then subtracting this background from the total derivative curves. The area under the background-corrected derivative curves represents the absolute intensity drop associated with the Verwey transition (Δ JTV ). This is caused by the aeolian coarse-grained magnetite, which is very sensitive to the changes in the intensity of the winter monsoon, and in turn related to the changes in palaeoclimate. The results show that the sharp drop of Δ JTV at 39.44 m corresponds to the climatic boundary from L2 (MIS 6) to S1S3 (MIS 5e), and not at 39.8 m as thought previously. Thus, the palaeosol deposits just below this boundary are in fact highly altered L2 materials instead of S1S3 accumulations. [ABSTRACT FROM AUTHOR]

The Chinese loess/paleosol sequences can provide excellent paleomagnetic records for detailed studies on both magnetostratigraphy and secular variations of the Earth’s magnetic field. However, the nature of the loess/paleosol characteristic remanent magnetization (ChRM), isolated by thermal demagnetization from the natural remanent magnetization, still remains in debate. In this study, we directly measure the thermal, alternating field, and low-temperature demagnetization (cooling/warming cycle of remanence in zero field between 300 and 50 K) spectra of ChRM of the loess samples at Touxiangdao, Xining, PR China. The results show that coarse-grained, pseudo-single-domain (PSD)/multi-domain (MD) magnetite and PSD maghemite particles are the main magnetic carriers of the loess and paleosol ChRMs, respectively. By comparing the ChRM characteristics across a loess/paleosol transition zone, we have found that during pedogenesis, the thermally separable ChRM (original detrital remanent magnetization) carried by the PSD/MD magnetite in loess is gradually overprinted by the chemical remanent magnetization carried by PSD maghemite. Even moderate pedogenesis (e.g., for the pedogenically altered loess) can strongly affect the loess ChRM. Thus more attention has to be focused on the paleosol ChRM separated solely by thermal demagnetization, especially when constructing a continuous paleomagnetic record covering both loess and paleosol units. [Copyright &y& Elsevier]

Abstract: A combined palaeomagnetic and geochronologic study has been conducted on a basaltic lava sequence of five flows at Jianchang in Liaoning Province, northeastern China. Radiometric 40Ar/39Ar dating indicates that the volcanism occurred at about 119Ma within the marine anomaly C34n in Cretaceous normal superchron (CNS). Rock magnetic investigations show that pseudo-single domain (PSD) or a mixture of single domain and multi-domain grain titanium-poor titanomagnetite is dominant in the studied lava flows. Both stepwise thermal and alternating field demagnetizations isolate the well-defined normal characteristic remanent magnetization (ChRM) in five independent lava flows with a mean direction of D/I =11.1°/57.2° (α 95 =5.7°). Palaeointensity was determined using the Coe modified Thellier method with systematic partial thermoremanent magnetization (pTRM) checks. All together, 61 samples from 286 samples with positive pTRM and tail checks yield palaeointensities ranging between 10.1 and 73.6μT. To further check the effects of thermal alteration on the palaeointensity results, a new ratio (M rs,480°C/M rs,25°C, where M rs,25°C and M rs,480°C are the room temperature saturation isothermal remanent magnetizations for the raw sample and the product after a 480°C thermal treatment, respectively) is proposed. Results show that the ratio changes significantly even for those samples with positive pTRM check. We further put forward that palaeointensity results are acceptable with ratio between 0.9 and 1.1. With this new criteria, 17 samples show consistent palaeointensity results with an average of 20.0±3.2μT. This value corresponds to the virtual dipole magnetic moments (VDM) of (3.5±0.6)×1022 Am2, which is about half of the value of present field. This finding, combined with other available results, suggests that magnetic field of the Earth just at the onset of the CNS is characterized by a weak palaeointensity. [Copyright &y& Elsevier]

Abstract: Magnetosomes produced by magnetotactic bacteria are of great interest for understanding bacterial biomineralization along with sedimentary magnetism and environmental magnetism. One of the most intriguing species, Magnetobacterium bavaricum can synthesize hundreds of bullet-shaped magnetite magnetosomes per cell, which contribute significantly to magnetic properties of sediments. However, the biomineralization mechanism and magnetic properties of such magnetosomes remain unknown. In this paper, we have conducted a comprehensive study of the crystallography and magnetic properties of bullet-shaped magnetosomes formed by uncultivated giant rod magnetotactic bacteria (referred to as MYR-1), recently discovered in Lake Miyun (Beijing, China). Transmission electron microscopy observations reveal that each MYR-1 cell contains hundreds of bullet-shaped magnetite magnetosomes, which are arranged into 3 - 5 braid-like bundles of chains. The formation of the bullet-shaped magnetosomes can be divided into two stages: initial isotropic growth (up to ∼ 20nm) followed by elongation along the [100] direction, which is unusual compared with the expected [111] magnetic easy axis. Although the [100] orientation is the hard axis of the face-centered cubic magnetite, the shape anisotropy of bullet-shaped magnetosomes and intra-bundle magnetostatic interactions confine the magnetization direction of the chain along the long axis of the cell/bundle. Due to each bundle of magnetosome chains effectively behaving as an elongated single domain particle, the MYR-1 cells show high coercivity, weak intra-bundle magnetostatic interaction, and high δ-ratio. These results provide new insights into the biomineralization process and magnetic properties of bullet-shaped magnetite magnetosomes. [Copyright &y& Elsevier]

Abstract: Rapid East Asian Monsoon oscillations recorded by Chinese loess are thought to be dynamically linked to north Atlantic climate. However, few efforts have been made to assess the effects of post-depositional processes (e.g., surface mixing and pedogenesis) on loess paleoclimatic records. Here a detailed optically stimulated luminescence dating of a thick loess sequence from the western Loess Plateau is presented, offering a reliable chronology for last glacial deposits. Magnetic susceptibility and mean grain size records from three loess–paleosol sequences along a northwest–southeast transect are investigated to evaluate impacts of post-depositional processes on these loess-based proxy records. Our results indicate that: (1) loess sequences developed within the flat tableland of the central and western Loess Plateau are nearly continuous during the last glaciation; and (2) post-depositional processes have distinct impacts on rapid monsoon signals recorded in loess sequences from different regions. In the central Loess Plateau, rapid monsoon signals have been attenuated to various degrees depending on the sedimentation rate and pedogenic intensity. In the northwestern Loess Plateau, however, due to high sedimentation rate and relatively weak pedogenesis, high-resolution grain size oscillations reliably record rapid monsoon changes and can be well correlated to rapid climate changes recorded in the Greenland ice core and Hulu cave stalagmite. [Copyright &y& Elsevier]

Schematic late Mesozoic tectonic evolution of SE Asia. The convergence between the Luconia block and the South China continent emerged approximately between 128.5 Ma and 79.5 Ma. SCC: South China continent; DS: Dongsha volcanic arc; CS: Chaoshan Depression; LB (RB): Liyue Bank (Reed Bank); SWB: SW Borneo; NWS: NW Sulawesi; PPO: Paleo-Pacific Ocean; PSCS: proto-South China Sea (the remnant oceanic crust of the Paleo-Pacific Ocean). [Display omitted] • Early Cretaceous thrust faults developed in the Nansha block and Chaoshan Depression. • The thrust nappe structures formed approximately between 128.5 Ma and 79.5 Ma. • The collision between Nansha block and South China block formed the thrust structure. The Mesozoic and Cenozoic tectonic evolution of South China is important for understanding the transition from subduction to extension related to the Paleo-Pacific plate. Here, the compressive structures of Lower Cretaceous sequences in the Liyue Bank (Reed Bank) and Nansha block (Dangerous Grounds) are presented using drilling data from Mesozoic strata and seismic data. Both south-directed and north-directed thrust nappes developed on the southern margin of the South China Sea. In addition, we observed a series of Early Cretaceous compressive structures in the Chaoshan Depression along the northern margin of the South China Sea. The compressive structures are accompanied by sedimentary environment changes from abyssal to continental deposition between 128.5 Ma and 79.5 Ma, which is perhaps associated with the collision between the South China block and Luconia block (Luconia-Dangerous Grounds-Reed Bank). The late Mesozoic thrust structures in the Chaoshan Depression and Liyue Bank (Reed Bank) and Nansha block (Dangerous Grounds) are related to the subduction of the Paleo-Pacific Ocean. [ABSTRACT FROM AUTHOR]

Abstract: A high-resolution mineral magnetic investigation has been carried out on the Jingbian loess/paleosol sequence at the northern extremity of the Chinese Loess Plateau. Results show that the magnetic assemblage is dominated by large pseudo-single domain and multidomain-like magnetite with associated maghemite and hematite. Variations in the ratios of SIRM100mT/SIRM, SIRM100mT/SIRM30mT and SIRM100mT/SIRM60mT (SIRM is the saturation isothermal remanent magnetization; SIRM nmT represents the residual SIRM after an n mT alternating field demagnetization) have been used to document regional paleoclimate change in the Asian interior by correlating the mineral magnetic record with the composite δ 18O record in deep-sea sediments. The long-term up-section decreasing trend in those ratios in both loess and paleosol units has been attributed to a long-term decrease in the relative contributions of eolian hematite during glacial extrema and of pedogenic hematite during interglacial extrema, respectively, which reveals a long-term decreasing trend in chemical weathering intensity in both glacial-stage source region (the Gobi and deserts in northwestern China) and interglacial-stage depositional area (the Loess Plateau region). We further relate this long-timescale variation to long-term increasing aridification and cooling, during both glacial extrema in the dust source region and interglacial extrema in the depositional area, over the Quaternary period. Changes in those ratios are most likely due to Quaternary aridification and cooling driven by ongoing global cooling, expansion of the Arctic ice-sheet, and progressive uplift of the Himalayan–Tibetan complex during this period. [Copyright &y& Elsevier]

Abstract: Atmospheric mineral dust aerosols affect Earth’s radiative balance and are an important climate forcing and feedback mechanism. Dust is argued to have played an important role in past natural climate changes through glacial cycles, yet temporal and spatial dust variability remain poorly constrained, with scientific understanding of uncertainties associated with radiative perturbations due to mineral dust classified as “very low”. To advance understanding of the dust cycle, we present a high-resolution dust record from the Red Sea, sourced principally from Arabia, with a precise chronology relative to global sea level/ice volume variability. Our record correlates well with a high-resolution Asian dust record from the Chinese Loess Plateau. Importing our age model from the Red Sea to the Chinese Loess Plateau provides a first detailed millennial-scale age model for the Chinese loess, which has been notoriously difficult to date at this resolution and provides a basis for inter-regional correlation of Chinese dust records. We observe a high baseline of dust emissions from Arabia and China, even through interglacials, with strong superimposed millennial-scale variability. Conversely, the distal EPICA Dome C Antarctic ice core record, which is widely used to calculate the radiative impact of dust variations, appears biased to sharply delineated glacial/interglacial contrasts. Calculations based on this Antarctic dust record will therefore overestimate the radiative contrast of atmospheric dust loadings on glacial/interglacial timescales. Additional differences between Arabian/Asian and circum-Saharan records reveal that climate models could be improved by avoiding ‘global mean’ dust considerations and instead including large-scale regions with different dust source variability. [Copyright &y& Elsevier]

Abstract: Magnetostratigraphic studies have established a first-order chronological framework for the Paleolithic sites in the Nihewan Basin (North China), which enabled tracking early human evolution in East Asia. However, to fully understand how well early humans were adapted to climate change, a truly precise dating of the Paleolithic sites is required. Here, we established a high-resolution astronomical timescale for the Xiantai and Donggutuo fluvio-lacustrine successions at the eastern margin of the Nihewan Basin employing low-field magnetic susceptibility (χ) as a climatic indicator, aiming to further refine the ages of the Xiantai, Donggutuo and Maliang Paleolithic sites. Starting from an initial age model constrained by geomagnetic reversals, larger-scale χ cycles were firstly tuned to orbital obliquity using an automatic orbital tuning method. This first-order tuning was followed by simultaneously tuning χ to both obliquity and precession. The finally tuned χ records can be correlated almost cycle-by-cycle with the quartz grain-size record of the Chinese loess sequence and the marine δ 18O record. The astronomically estimated age of the Xiantai Paleolithic site is ca. 1.48Ma, corresponding to paleosol layer S20 of the Chinese loess sequences or marine oxygen isotope stage (MIS) 49, an interglacial period. The astronomical estimate for the Donggutuo Paleolithic site ranges from ~1.06Ma to 1.12Ma, corresponding to paleosol/loess layers S11–S12 or MIS 31–33, spanning both interglacial and glacial periods. The astronomically estimated age of the Maliang Paleolithic site is ~0.79Ma, corresponding to loess layer L8 or MIS 20, a glacial period. This astronomical finding further implies that early humans may have permanently occupied China as far north as 40oN since at least 1.1Ma, and before this time the occupation may be intermittent. [ABSTRACT FROM AUTHOR]

Abstract: The fluvio-lacustrine sequence in the Nihewan Basin is an important archive of Pleistocene climate and environmental changes in northern China, which provides excellent sources of early human settlements in high-latitude East Asia. Here a long-term environmental record from the Pleistocene fluvio-lacustrine sequence in this basin is revealed, based on selected major element pairs that are sensitive to paleoenvironmental changes. Results reveal a long-term increasing trend in aridification/cooling in the Nihewan Basin since the early Pleistocene. This provides a general setting for early human colonization in high-latitude northern China (around 40° N). The intensified aridification/cooling is envisaged to reduce tree cover and increase open savanna grass area. This, in turn, would promote prominent flourishing population and migration of savanna-adapted early humans in the Old World. Therefore, the cold/dry climate may have contributed to the evolution and expansion of early humans in the high-latitude northern China, rather than bringing hardship, as is often thought. [ABSTRACT FROM AUTHOR]

Abstract: The Nihewan fluvio-lacustrine sequence (North China) has recorded late Pliocene–Pleistocene climatic and environmental changes, and contains valuable information on early human evolution in high-latitude East Asia. We carried out a combined mineral-magnetic and geochemical investigation on a sequence from the Xiantai section, eastern Nihewan Basin. Results suggest that large-amplitude magnetic-property variations between so-called ‘high-magnetic’ and ‘low-magnetic’ units mainly result from preservation/dissolution cycles of detrital magnetic minerals in alternating oxic and anoxic depositional environments. In our preservation/dissolution model, the high- and low-magnetic units represent glacial and interglacial deposits, respectively. This contributes to a better understanding of the link between magnetic properties and climate in the Xiantai fluvio-lacustrine sequence. Based upon this relationship, early humans may have occupied the Xiantai and Xiaochangliang sites during an interglacial period, during both interglacial and glacial periods at the Donggutuo site, and during a glacial period at the Maliang site. Our work provides a paleoenvironmental context for early human adaptation and occupation in mainland East Asia during the early Pleistocene. [Copyright &y& Elsevier]

• Nanosized hydrous zirconium oxide (HZrO) is decorated on anion exchange resin D201. • HZrO@D201 exhibits outstanding selective V(V) adsorption with co-existing anions. • Adsorption thermodynamics and adsorption kinetics are systematically studied. • HZrO@D201 indicates a satisfactory lifespan in column experiment for V(V) removal. Adsorption is widely used in removal of toxic vanadium (V) [V(V)] from water streams, and a fit-for-purpose adsorbent plays a vital role in this process. Herein HZrO@D201, an adsorbent with decoration of nanosized hydrous zirconium oxide (HZrO) on anion exchange resin D201, is fabricated for efficient V(V) removal. Compared to pristine D201, HZrO@D201 excelled in V(V) removal with a maximum adsorption capacity of 118.1 mg/g, due to potential formation of inner sphere complexation between V(V) and HZrO. HZrO@D201 could also functioned well in a wide pH range (3.00 to 9.00) and exhibited outstanding selective V(V) adsorption under the presence of competing anions (chloride, nitrate, sulfate, and phosphate). The adsorption thermodynamics was in accordance with the Langmuir model, while adsorption kinetics followed the Pseudo-Second-Order model. When treating actual vanadium contaminated groundwater from Panzhihua region (China), HZrO@D201 indicated a satisfactory lifespan in the column experiment for V(V) removal (2.41 times longer than D201), and the treated groundwater could meet the vanadium standard of drinking water source in China (less than 50 μg/L). Regeneration of HZrO@D201 was easily achievable with negligible capacity loss. Results from this work suggests a promising application potential of HZrO@D201 in vanadium pollution control. [ABSTRACT FROM AUTHOR]

The South China Sea (SCS) is connected to the West Pacific through a deep channel in the Luzon Strait. Thus the SCS deep water is sensitive to the evolution of Pacific Ocean circulation, which significantly influences the global climate system. Geochemical data (Pb isotope and redox-sensitive elements data) and magnetic data were determined for a Fe–Mn nodule obtained from Jiaolong seamount in the central SCS. These records reflect interactions between changes in ice sheets, deep Pacific circulation, and weathering inputs to the deep SCS during the Pliocene and Quaternary. Our results show that the SCS deep-water environment can be divided into three major Stages (Stages 1–3). Stage 1 (∼4.8–1.4 Ma) was characterized by a well-oxygenated Pacific Deep Water (PDW) and lower dust inputs; then moderate stable deep-water ventilation and greater inputs of Asian dust occurred during Stage 2 (1.4–0.9 Ma). During Stage 3 (<0.9 Ma), a more isolated PDW was accompanied by sluggish Pacific overturning circulation, probably due to the weakened southern-sourced deep-water formation. In general, the progressive intensification of northern hemisphere ice-sheet play an active role in controlling the variation of the deep-water environment in the SCS. Interestingly, the variation in deep-water ventilation lagged behind weathering and erosion around the Middle Pleistocene Transition, which strongly indicates that the ocean and continent environments had different sensitivities to the global paleoclimatic changes at the glacial climate boundary. [ABSTRACT FROM AUTHOR]

The extreme environment caused by the typhoon has destroyed several wind turbines in recent decades and already become a restriction to the further development of offshore wind turbines of China. Due to the destructive energy in the typhoon, the conventional active control method for load mitigations of the blades such as the yaw and pitch systems are difficult to implement effectively. Therefore, the adaptive blade that can mitigate the extreme load passively may be a more promising method. In this paper, the adaptive bend–twist coupling blades were investigated on their load mitigation effects. According to a parameterized modeling process, the high fidelity CFD and FEM models for different kinds of bend–twist coupling blades are established. Then the FSI simulations are used to study the mitigating effects of these blades when the blade suffers the extremely dangerous conditions in typhoon environment. The results demonstrate that the swept blade combined with the material coupling can effectively reduce the aerodynamic load and the maximum stress due to the special pattern of the blade deformation. For the case which is easy to cause a high frequent vortex vibration, the swept blades also show a good performance to decrease the dominant frequency and amplitude of the load fluctuation, which is helpful to avoid damages caused by the resonance vibration. • Using the adaptive blade to mitigate the extreme load caused by the typhoon. • Using a parametric method to rapidly created different kinds of bend-twist coupling blades. • The high-fidelity FSI method is used to investigate the ability of load mitigation of adaptive blades. • The adaptive blades can effectively mitigate the structure stress in the extreme environment. [ABSTRACT FROM AUTHOR]

Background: Copper exposure is reported to be associated with increased risk of stroke. However, the association of copper exposure with subclinical carotid atherosclerosis remains unclear., Methods and Results: This observational study included consecutive participants from Xinqiao Hospital between May 2020 and August 2021. Blood metals were measured using inductively coupled plasma mass spectrometry and carotid atherosclerosis was assessed using ultrasound. Modified Poisson regression was performed to evaluate the associations of copper and other metals with subclinical carotid plaque presence. Blood metals were analyzed as categorical according to the quartiles. Multivariable models were adjusted for age, sex, body mass index, education, smoking, drinking, hypertension, diabetes, dyslipidemia, estimated glomerular filtration rate, and coronary artery disease history. Bayesian Kernel Machine Regression was conducted to evaluate the overall association of metal mixture with subclinical carotid plaque presence. One thousand five hundred eighty-five participants were finally enrolled in our study, and carotid plaque was found in 1091 subjects. After adjusting for potential confounders, metal-progressively-adjusted models showed that blood copper was positively associated with subclinical carotid plaque (relative risk according to comparing quartile 4 to quartile 1 was 1.124 [1.021-1.238], relative risk according to per interquartile increment was 1.039 [1.008-1.071]). Blood cadmium and lead were also significantly associated with subclinical carotid plaque. Bayesian Kernel Machine Regression analyses suggested a synergistic effect of copper-cadmium-lead mixture on subclinical carotid plaque presence., Conclusions: Our findings identify copper as a novel risk factor of subclinical carotid atherosclerosis and show the potential synergistic proatherogenic effect of copper, cadmium, and lead mixture.

Background: PKD1, which has a relatively high mutation rate, is highly polymorphic, and the role of PKD1 is incompletely defined. In the current study, in order to determine the molecular etiology of a family with autosomal dominant polycystic kidney disease, the pathogenicity of an frameshift mutation in the PKD1 gene, c.9484delC, was evaluated., Methods: The family clinical data were collected. Whole exome sequencing analysis determined the level of this mutation in the proband's PKD1, and Sanger sequencing and bioinformatics analysis were performed. SIFT, Polyphen2, and MutationTaster were used to evaluate the conservation of the gene and pathogenicity of the identified mutations. SWISS-MODEL was used to predict and map the protein structure of PKD1 and mutant neonate proteins., Results: A novel c.9484delC (p.Arg3162Alafs*154) mutation of the PKD1 gene was identified by whole exome sequencing in the proband, which was confirmed by Sanger sequencing in his sister (II7). The same mutation was not detected in the healthy pedigree members. Random screening of 100 normal and end-stage renal disease patients did not identify the c.9484delC mutation. Bioinformatics analysis suggested that the mutation caused the 3162 nd amino acid substitution of arginine by alanine and a shift in the termination codon. As a result, the protein sequence was shortened from 4302 amino acids to 3314 amino acids, the protein structure was greatly changed, and the PLAT/LH2 domain was destroyed. Clustal analysis indicated that the altered amino acids were highly conserved in mammals., Conclusion: A novel mutation in the PKD1 gene has been identified in an affected Chinese family. The mutation is probably responsible for a range of clinical manifestations for which reliable prenatal diagnosis and genetic counseling may be provided., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

The potential use of environmental magnetism to investigate heavy metal pollution was investigated by analyzing sediment samples from a short sediment core (Z07) from the Yellow River Estuary. The heavy metal concentrations and speciation, grain sizes, and magnetic properties were determined, and correlations between the parameters were identified. Strong exponential relationships were found between the Hg concentrations and χ fd %, χ ARM-20mT , and clay content. Linear correlations were found between the As, Cd, Co, Cr, Ni, Pb, and Zn concentrations and χ fd %, χ ARM-20mT , and clay content. This indicated that Hg was mainly sorbed to the surfaces of nano-sized magnetic and clay minerals and predominantly had anthropological sources but the other heavy metals had mineralogical and other natural sources. These conclusions were supported by the heavy metal fractionation results. Heavy metal concentrations in sediment at site Z07 have decreased markedly since 2003 in response to water and sediment regulations being implemented., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objective/hypothesis: The objective of this study was to determine the validity of our laryngopharyngeal reflux (LPR) diagnostic system from our previous study (Witt et al.) against the results of a standard pH probe monitoring. We hypothesized that subjects with abnormal pH probe results demonstrate color and texture abnormalities that would be classified as LPR according to artificial neural network (ANN) analysis., Study Design: Retrospective analysis., Methods: Eighty-two subjects, including 18 pH-positive, 11 pH-negative, and 53 control subjects were tested for LPR through multichannel intraluminal impedance 24-hour pH (MII-24pH) monitoring. Laryngoscopic images of all subjects were obtained. The hue and texture values of seven areas of interest, including true vocal folds, false vocal folds, arytenoids, and interarytenoid, were quantified using a hue calculation and two-dimensional Gabor filtering. These served as inputs for the ANN. This was used to classify images through pattern recognition, and a receiver operating characteristic (ROC) analysis was performed to determine the effectiveness of the diagnosis., Results: Classification accuracy for the combined hue and texture was 87.40%, with an area under the ROC curve of 0.910., Conclusion: Although a previous study conducted classification based on RFS, this study suggests that color and texture analysis may be used to classify images based on the results of pH probing, a more objective approach for diagnosis. Additional studies should include more subjects to produce an even more accurate reading, and will use the color/texture analysis tool to test and confirm this application in a clinical setting., Level of Evidence: 3B. Laryngoscope, 127:665-670, 2017., (© 2016 The American Laryngological, Rhinological and Otological Society, Inc.)