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The lower reaches of the Minjiang River are located in an area of land-sea-air interaction. It is not only a sensitive area concerning environmental evolution, but also a hotspot for archaeological research on the southeast coast of China. Exploring the scope of ancient human activities and the evolution of land-use patterns is of great significance for understanding the development of human-land relations. By generating various cost surfaces of sites through GIS cost distance analysis and combining with the site catchment theory and method, we comprehensively analyzed the human activity range and land-use pattern in every cultural period from the Neolithic to the Bronze Age in the lower reaches of the Minjiang River and reconstructed the potential population in each period of the region. The results show that: (1) the area of site catchment, available and actually developed land increased from the Keqiutou to Huangtulun culture period in the lower reaches of the Minjiang River. Chronologically, the area of the site catchment continues to grow from 212 km2 to 4,858 km2, the accessible land area increased from 261 km2 to 7,599 km2, and the land area that was actually used by ancient humans continuously increased from 173 km2 to 3,914 km2. (2) With the development process of culture, the land-use intensity of prehistoric humans in the region first increased and then decreased by 81.58%, 92.95%, 87.99%, 79.33% and 80.57%, respectively, and the degree of land development was reduced, which may be related to the development and progress of productive forces. The frequency of ancient human exchanges can be represented by the ratio of the number of sites in the overlapping site catchment to the total number of sites in the same period (87.50%, 60.00%, 66.67%, 92.54%, and 97.81%, respectively). (3) The reconstruction results showed that the potential population in the area continued to expand, with substantial population growth in the lower Tanshishan-Tanshishan and Huangguashan-Huangtulun transitional periods. It was inferred that there was a relationship between population pressure and culture succession.

Prehistoric human cultural sites along the eastern coast of Fujian Province are important records for studying the origin and spread of the Austronesian civilization. The Huangqiyu site is the first Tanshishan culture site to be unearthed in the Min River estuary area and was excavated by scientific archeology. It has great significance for further research of the Tanshishan culture and the coupled relationship between prehistoric human activities and environmental changes in the Fujian coastal region. The chronology of archeological sites is an important foundation for prehistoric archeology. In this study, the burial age of the Huangqiyu site in Lianjiang County was analyzed using the Optically Stimulated Luminescence (OSL) dating technique on the basis of Accelerator Mass Spectrometry (AMS) 14C dating. In the field, the T2 section of the Huangqiyu site was selected for sampling, and the single-aliquot regeneration dose method of medium-grained quartz was used to assess OSL chronology in the laboratory. The results showed that the OSL burial age of the Huangqiyu site ranges from approximately 8.5 ± 0.5 to 4.4 ± 0.2 ka, corresponding to the sedimentary/cultural strata of the early Middle Holocene. The OSL age of sample 2019118, which was consistent with the AMS 14C age, was 4.4 ± 0.2 ka, corresponding roughly to the Tanshishan culture. The age of sample 2019117 was 5.4 ± 0.3 ka, which may be an overestimation because the equivalent dose of this sample showed a weakly skewed distribution with a tail at the high value end, indicating that there was a small amount of sundry particles and that the drying was insufficient. This problem may have led to a bias in the measured equivalent dose and, in turn, to overestimation of the age of the sample. The age of sample 2019119, which was affected by the sampling environment, was 8.5 ± 0.5 ka, possibly indicating the maximum age of the bottom boundary of the site. Archeological studies have found that the age indicated by the pottery features excavated from the cultural layer at the bottom of the Huangqiyu site is most likely earlier than the Tanshishan culture, or possibly that of the lower strata of the Tanshishan culture. Overall, the ages of samples 2019117 and 2019119 are different from the AMS 14C ages, but these are consistent with the archeological characteristics of the site. By comparing the geomorphological and environmental evolution process of the Fuzhou Basin, where the Huangqiyu site is located, with the regional prehistoric human activities, it was found that the site corresponds to the warm climate of 6 500-4 000 a B P and relatively a high sea level period. Many prehistoric remains were developed in the Fuzhou Basin during this period, and the prosperous Tanshishan culture and the lower Tanshishan culture emerged in the region. At the end of the Neolithic age, the abrupt cold event of 4.2-4.0 ka, the drastic change of climate and environment in the tropical and subtropical regions on both sides of the Pacific Ocean at 4 000-3 000 a B P, and the invasion of the northern Wu-Yue culture may explain the disappearance of the follow-up culture. Because of the limited precision of the regional sea-level change curve, it is insufficient to discuss sea-land change and the coupled relationship with human activities. Relevant studies need to strengthen these aspects in the future.

Alluvial-lacustrine deposits are important carriers for studying paleo-hydrological information and the evolution of paleo-environments. In this study, a total of 6 optically stimulated luminescence (OSL) samples from 2 profiles in the lower and middle reaches of the Hutubi River in the North Tianshan Mountains were dated, and a comprehensive analysis was conducted by integrating sedimentary structures, grain sizes, and magnetic susceptibility characteristics to explore the sedimentary environment patterns and regional evolution processes during the Mid to late Holocene. The results revealed the following findings: (1) The OSL signal of quartz samples indicates the predominance of fast components, allowing reliable dating of regional fluvial sediments using the appropriate condition-tested coarse-grained quartz single-aliquot regenerative dose (SAR) protocol within the 90–125 μm range. (2) Analysis of sedimentary structures, grain sizes, and magnetic susceptibility characteristics reveals lithofacies of heterotopic synchronous or homotopic asynchronous in exposed profiles, with predominantly poorly sorted fine and very fine sand. Magnetic susceptibility is primarily controlled by the content of magnetic minerals in the coarse particles, while also being influenced by the combined effects of provenance input and depositional environment, indicating a complex regional sedimentary environment influenced by variable hydrodynamic conditions driven by fluvial processes. (3) Based on OSL dating results and the analysis of various environmental proxy indicators, it is determined that the climatic environment in the Middle and Late-Holocene in the downstream areas of the northern piedmonts of the Tianshan Mountains demonstrates a fluctuating pattern of wet and dry alternations. The sedimentary environment shifted from a stable state in the Mid-Holocene to an unstable state in the Late-Holocene. The intermittent appearance of wet records may be associated with increased river activity caused presumably by the release of high-altitude ice due to rising temperatures and warming conditions. [ABSTRACT FROM AUTHOR]

Aiming at the problems of high performance，high requirements and difficult processing of power electronic device driving pulse signal，a high performance pulse signal processing circuit module is designed and fabricated, and the design is completed by EDA high speed circuit technology. LTspice simulates the circuit system and conducts experimental test. Compared with the domestic research status, the test index has been significantly improved. The high-speed pulse forward rectification of 1 MHz is realized, the output level is controllable, the pulse width adjustment range is 20% to 60%, and the upper and lower edge time is controlled within 25 ns, wherein the falling edge time as low as 13 ns, the transmission delay adjustment range is 20 ns to 110 ns, and the 2 MHz pulse signal indicators are also greatly improved, thereby effectively improving the efficiency of the drive circuit and the main circuit. Further optimizing the selection and layout of the device and adopting a more sophisticated manufacturing process, it is expected to process pulse signals with a frequency of up to 5 MHz, making the power electronic circuit more integrated and efficient.

Southeastern China's coastal region is considered one of the key areas for studying prehistoric human–land relationships in the Western Pacific region. This region, which is rich in records of marine civilization, provides an ideal location for recording coastal environmental evolution. In this study, the chronological framework of three borehole cores recovered from Haitan Island, South China, near the Keqiutou group of sites, was established using both optically stimulated luminescence (OSL) and accelerator mass spectrometry radiocarbon (AMS 14C) dating techniques. Various analyses, including lithologic characteristics, chroma, clay–water electric conductivity (EC), grain size and elemental geochemistry, were conducted to elaborate the sedimentary sequence and its paleoenvironmental implications. The findings suggest that (i) since the late Quaternary, the Haitan Island sedimentary sequence can be divided into three deposition stages: Old Red Sand formed during Marine Isotope Stage 3 (MIS3), intermittent sedimentation during the Last Glacial Maximum and coastal aeolian deposition during the Holocene. Furthermore, the study reveals that terrestrial debris was significant as a material source for Haitan Island. (ii) Due to the absence of tectonic uplift, Haitan Island has no thick marine sedimentary record during the Holocene period of high sea level. The Luyangpu coastal sand sheet can be dated to 2.78 ka, which is consistent with previous reports giving dates of 2.4 ka. Prior to the formation of the sand sheet, the sedimentary environment in the area was characterized by lagoon or marsh facies. (iii) Paleoanthropological activities were influenced by sedimentary environmental evolution and geomorphic processes, among others. The Keqiutou Culture experienced high sea levels, which created an intertidal environment near the site and facilitated fishing. However, regression at 5.7 ka led to terrestrial environments, which prompted the inhabitants to migrate. Approximately 3 ka ago, sea levels rose again, coinciding with the initiation of rice cultivation. These factors may have influenced the transition from the Neolithic to Bronze Age culture. This study reconstructs evolution of the sedimentary sequence since the late Quaternary, enhancing our understanding of past human–terrestrial relationship in the region. [ABSTRACT FROM AUTHOR]

Laterite is a red weathering crust developed with various rocks and Quaternary loose sediments as its parent material in the tropics and subtropics regions of the world. Since the 1930s, researchers have believed that the fluvial reticulated laterite in southern China was influenced by the warm and humid climate of the Middle Pleistocene. In recent years, the remains of Paleolithic human activities are often found in the reticulated laterite of southern China. However, the study of laterite chronology is sporadic or there is no critical chronological analysis, which causes uncertainty in the identification and discussion of the ages of reticulated laterite and Paleolithic sites. In this study, a Paleolithic site found in fluvial reticulated laterite in South China was systematically tested by quartz optical luminescence dating and geomorphic process analysis. The results show that, (a) The T3 terrace, an archive of hominin activity in the study area, primarily formed between 56 and 11 ka. (b) Reticulated laterite cannot be used simply to determine the ages of the Paleolithic sites found in this stratum, and typical reticulated laterite cannot be used as a marker for climatic stratigraphy and chronostratigraphy. The fluvial reticulated laterite in the southern tropics, under suitable hydrothermal conditions, can form within tens of thousands of years or even within 10 ka. (c) Human activities can affect the burial age of reticulated laterite, and the stratigraphic diachronism of riverine terraces can also lead to an inversion in the age of reticulated laterite. Key Points: This is one of the few systematic chronological studies of Paleolithic sites for the presence of Upper Paleolithic man in Fujian, ChinaAncient humans have occupied this area within the late Pleistocene. Human activities can affect the burial age of reticulated red soilReticulated laterite cannot be used simply to determine the ages of the Paleolithic sites in subtropical China [ABSTRACT FROM AUTHOR]

Most computer vision algorithms for water level measurement rely on a physical water gauge in the image, which can pose challenges when the gauge is partially or fully obscured. To overcome this issue, we propose a novel method that combines semantic segmentation with a virtual water gauge. Initially, we compute the perspective transformation matrix between the pixel coordinate system and the virtual water gauge coordinate system based on the projection relationship. We then use an improved SegFormer-UNet segmentation network to accurately segment the water body and background in the image, and determine the water level line based on their boundaries. Finally, we transform the water level line from the pixel coordinate system to the virtual gauge coordinate system using the perspective transformation matrix to obtain the final water level value. Experimental results show that the improved SegFormer-UNet segmentation network achieves an average pixel accuracy of 99.10% and an Intersection Over Union of 98.34%. Field tests confirm that the proposed method can accurately measure the water level with an error of less than 1 cm, meeting the practical application requirements. [ABSTRACT FROM AUTHOR]

The photoionization and dissociative photoionization of m-xylene (C8H10) were researched by using synchrotron radiation vacuum ultraviolet (SR-VUV) and supersonic expanding molecular beam reflectron time-of-flight mass spectrometer (RFTOF-MS) system. The photoionization efficiency spectra (PIEs) of parent ion C8H10+ and main fragment ions C8H9+ and C7H7+ were observed, and the ionization energy (IE) of m-xylene and appearance energies (AEs) of main fragment ions C8H9+ and C7H7+ were determined to be 8.60±0.03 eV, 11.76±0.04 eV and 11.85±0.05 eV, respectively. Structures of reactant, transition states (TSs), intermediates (INTs), and products involved in two dominant dissociation channels were optimized at the B3LYP/6-311++G(d,p) level, and the relative energies were calculated at the G3 level. Based on the results, two major dissociative photoionization channels, C7H7++CH3 and C8H9++H were calculated at the B3LYP/6-311++G(d,p) level. On the basis of theoretical and experimental results, the dissociative photoionization mechanisms of m-xylene were proposed. The C–H or C–C bond dissociation and hydrogen migration are the main processes in the dissociation channels of m-xylene cation. [ABSTRACT FROM AUTHOR]

Space-time image velocimetry (STIV) technology has achieved good performance in river surface-flow velocity measurement, but the application in a field environment is affected by bad weather or lighting conditions, which causes large measurement errors. To improve the measurement accuracy and robustness of STIV, we combined STIV with deep learning. Additionally, considering the light weight of the neural network model, we adopted MobileNetV2 and improved its classification accuracy. We name this method MobileNet-STIV. We also constructed a sample-enhanced mixed dataset for the first time, with 180 classes of images and 100 images per class to train our model, which resulted in a good performance. Compared to the current meter measurement results, the absolute error of the mean velocity was 0.02, the absolute error of the flow discharge was 1.71, the relative error of the mean velocity was 1.27%, and the relative error of the flow discharge was 1.15% in the comparative experiment. In the generalization performance experiment, the absolute error of the mean velocity was 0.03, the absolute error of the flow discharge was 0.27, the relative error of the mean velocity was 6.38%, and the relative error of the flow discharge was 5.92%. The results of both experiments demonstrate that our method is more accurate than the conventional STIV and large-scale particle image velocimetry (LSPIV). [ABSTRACT FROM AUTHOR]

Many prehistoric sites are preserved in the southeast China coastal area; however, it is still unclear when ancient human activity occurred owing to a lack of chronological evidence, which is unfavourable for research on the coupling of prehistoric man-earth relationships. In this study, we present an optically stimulated luminescence (OSL) chronology analysis of two profiles (T1 and T4) collected from the Neolithic Jianhu (JH) site on Haitan Island, South China. The single-aliquot regenerative-dose (SAR) protocol for coarse silt (38–63 μm) quartz was used to determine the equivalent dose (De). The results showed that the OSL technology is reliable and of great value for archaeochronology in coastal aeolian regions. The results suggest that the JH site is one of the earliest Neolithic sites in the coastal area of Fujian. The ages of cultural layers with ancient human activities at the JH site varied from 7.4 ± 1.13 to 5.77 ± 0.35 ka, thereby making the JH site the earliest Neolithic site in the coastal area of Fujian. The sand-tempered pottery unearthed from the JH site can be used as direct evidence of ancient human survival, and its age is 6.33 ± 0.21 ka with a high precision, which presents the earliest OSL data on pottery in South China. We also discuss the regional environmental background of ancient human activity. The Keqiutou culture corresponds to a period of relatively high sea level and a superior natural environment on Haitan Island. The sea retreat 5.7 ka ago was a crucial factor driving prehistoric human migration to the Fuzhou Basin and Taiwan Island. [ABSTRACT FROM AUTHOR]

Semantic segmentation of remote sensing images has received increasing attention in recent years; however, using a single imaging modality limits the segmentation performance. Thus, digital surface models have been integrated into semantic segmentation to improve performance. Nevertheless, existing methods based on neural networks simply combine data from the two modalities, mostly neglecting the similarities and differences between multimodal features. Consequently, the complementarity between multimodal features cannot be exploited, and excess noise is introduced during feature processing. To solve these problems, we propose a multimodal fusion module to explore the similarities and differences between features from the two information modalities for adequate fusion. In addition, although downsampling operations such as pooling and striding can improve the feature representativeness, they discard spatial details and often lead to segmentation errors. Thus, we introduce hierarchical feature interactions to mitigate the adverse effects of downsampling and introduce a two-way interactive pyramid pooling module to extract multiscale context features for guiding feature fusion. Extensive experiments performed on two benchmark datasets show that the proposed network integrating our novel modules substantially outperforms state-of-the-art semantic segmentation methods. The code and results can be found at https://github.com/NIT-JJH/CIMFNet. [ABSTRACT FROM AUTHOR]

Establishing a reliable chronology is the basis of archaeological research; this is normally undertaken using radiocarbon dating and, more recently, optically stimulated luminescence (OSL). The application of the latter to Neolithic sites in the Fujian Province of China is still quite limited. In this study, a total of eight OSL samples were collected from the Zhuangbianshan site (ZBS). The single‐aliquot regenerative‐dose (SAR) protocol was applied to coarse silt (38–63 μm) quartz. The results showed that the 38–63 μm grains appeared to be well bleached. The ages for the samples range from 5.5 to 3.3 ka for the ZBS sections, which is in general internally coherent within the limits of experimental errors and with respect to their stratigraphical order. Two OSL ages (ZBSH03‐2 and ZBST05H) of the ZBS were significantly older than their expected archaeological ages, while most of those from the ZBS core generally showed good agreement with their archaeological ages and stratigraphical succession. Based on the OSL ages, two periods (~6.3 and 3.5–3.3 ka, approximately) of rapid cultural accumulation can be identified at this site. These investigations indicate that the OSL technique is an effective method with which to date Holocene cultural accumulations, especially sites in the humid subtropical areas of South China where organic carbon material is sparse. [ABSTRACT FROM AUTHOR]

Background: Ketamine is a dissociative anesthetic, commonly used for analgesia and anesthesia in a variety of pediatric procedures. It acts as a non-competitive antagonist to block ion channels of the N-methyl-D-aspartate receptors (NMDARs). Our previous study showed that repeated ketamine exposure developed a compensatory increase in NMDAR-mediated currents in neurons of the anterior cingulate cortex (ACC) of neonatal rats, and this increase was largely mediated by the GluN2B subunit-containing receptors, a predominant type of NMDARs during embryonic and early development of the brain. These data provide the molecular evidence to support that immature neurons are highly vulnerable to the development of apoptotic cell death after prolonged ketamine exposure. Methods: Using whole-cell patch-clamp electrophysiology in an in vitro preparation of rat forebrain slices containing the ACC, the present study aimed at further determining whether GluN2B-containing NMDARs at extrasynaptic sites of immature neurons were the major target of ketamine for developing a compensatory increase in NMDAR-mediated synaptic transmission. Results: Our major findings were that GluN2B subunits played a significant role in mediating ketamine-induced blockade of NMDAR-mediated currents in neonatal neurons and GluN2B-containing NMDARs expressed at extrasynaptic sites in neonatal neurons were the major player in compensatory enhancement of NMDAR-mediated currents after repeated ketamine exposure. Conclusion: These results provide new evidence to strongly indicate that GluN2B-containing NMDARs at extrasynaptic sites are the key molecule contributing to the high vulnerability of the neonatal brain to ketamine-induced neurotoxic effects. [ABSTRACT FROM AUTHOR]

Recent environmental archeological evidence has started to throw light on both the timing and processes of human colonization of the Tibetan Plateau (TP). Yarlung Tsangpo (YT) valley, a very important region of the southern TP for occupation, is home to not only modern Tibetans but also their ancestors. However, a lack of suitable sedimentary strata has limited the establishment of a secure chronology. Here, we report on a new stratigraphic section with prehistoric pottery and cultural layers that was discovered on a terrace of the YT at Liena, in Nyingchi County. The cultural layers are overlain by, and bedded within, eolian and lacustrine sediments. We used the quartz Optically Stimulated Luminescence (OSL) method to date 11 samples and performed geochemical analysis on 100 samples to derive paleoenvironmental indicators. The OSL analysis gave an age of 4.3 ka BP for the cultural layer, which makes it the earliest human activity in the YT valley of Nyingchi to date. In addition, commencement of eolian deposition was dated to at least 8.3 ka, coinciding with the Holocene warm period. We discuss possible causal factors for human occupation in the valley and show that climatic changes played a crucial role in prehistoric human migration c. 8.3–4.3 ka BP. Before the early Holocene, most of the river terraces in the valley were being actively reworked by rivers or covered by lakes. So there were no suitable places for occupation by ancient populations. With the recession of dammed lakes during the Holocene warm period, the relatively flat and wide valley terraces, blanketed with rich eolian deposits (such as sandy loess), provided an attractive place for ancient people engaged in nomadic and even agricultural activities. Hence, the climate conditions of the Holocene warm period drove the environmental changes that provided favorable conditions for ancient human activities. [ABSTRACT FROM AUTHOR]

• The luminescence sensitivity characteristics of aeolian sediments in the east coast of China are systematically studied. • Quartz optically stimulated luminescence sensitivity of Pleistocene aeolian sediments is significantly higher than that of Holocene. The value of 80% of the fast component as a dividing line can be used to distinguish sediment age. • Sea level variations and regional climate change have had an impact on quartz luminescence sensitivity. Quartz luminescence signals have been proven to be an effective index for identifying sediment provenance. The provenance of quartz minerals on typical sandy coasts along the east coast of China serves as important evidence for estuarine and coastal aeolian geomorphological processes in coastal zones. However, the temporal and spatial differences in the sensitivity characteristics of quartz grains on the east coast of China remain controversial owing to a lack of systematic analyses of coastal sediments. In this study, we present the thermoluminescence (TL) and optical luminescence (OSL) sensitivity of quartz minerals from core FN1 in the coastal area of Fujian Province, and the relative OSL sensitivity of quartz minerals obtained from Hebei, Fujian, Hainan, and Taiwan provinces. Our results indicate that (1) the OSL sensitivity values of quartz grains in the FN1 core are closely correlated with the mean grain size, electrical conductivity, potential of hydrogen, and end-member, suggesting that the change in luminescence sensitivity may be closely related to climate changes; specifically, cold climatic events during this period can cause significant fluctuations in the sensitivity; further, the percentage contents of fast, medium, and slow components are also different; (2) spatially, there are clear differences between the %FAST value of quartz grains from different sandy coasts; in these coastal dune samples, the %FAST value of the quartz grains during the Last Glacial Maximum (LGM) was significantly different from that of the quartz grains during the interglacial; thus, %FAST can be used to distinguish between glacial and interglacial samples; specifically, the sensitivity of quartz from the glacial dune was higher than that from the interglacial dune, and the sensitivity dispersion of quartz from the glacial as smaller than that from the interglacial coastal dune sand; and (3) the change in the luminescence sensitivity of quartz grains was ultimately controlled by the provenance change. In different geological periods, transgression, regression, and abrupt climate change trigger changes in the supply range of sources, which indirectly affects the sensitivity characteristics of quartz minerals. The spatial difference in quartz sensitivity in the eastern coastal area of China is mainly affected by the characteristics of quartz crystals and types of bedrock, which require further systematic study. [ABSTRACT FROM AUTHOR]

A spatial microsimulation modeling and predictive policy analysis system called Micro-MaPPAS made for a local strategic partnership in a big urban area of the UK is presented. Some descriptive models of the policy relevance and policy analysis potential of the software is also given.

The chronologies of few Neolithic sites in the lower reaches of the Min River of China have been well investigated for the middle to late Holocene. In this study, the Hengyu Neolithic site in Fujian Province, South China, which has significant archaeological remains, was dated using blue‐stimulated optically stimulated luminescence (OSL) and accelerator mass spectrometry radiocarbon (AMS14C) techniques. The results, comprising nine OSL and three AMS14C ages through the Neolithic sequence, provide new evidence towards understanding the relationship between environmental evolution and human activities in the middle to late Holocene in the Fuzhou Basin and coastal areas of South China. The ages of the site deposits vary from 6.83 to 1.67 ka and can be divided into two main phases: the Keqiutou–Tanshishan culture period and the Bronze culture period. In contrast, the persistent periods of ancient human activities at the Hengyu site seem to correspond to regional sea‐level changes and the East Asian winter monsoon as a secondary factor, which can affect human activities through sea‐level impacts. The warm and high sea level conditions provided a liveable environment for the ancient humans of Fujian and even South China. The ages of two building column bases are linked to the early stage of the Han dynasty, suggesting a potentially favourable habitation environment; that is, ancient humans occupied and settled this area for the long term within this time period, which is consistent with sea‐level changes and palynology records. Copyright © 2019 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Minjiang River Basin in Fujian played a vital role in the southward spread of agriculture in China. To better understand the development of Neolithic cultures in this region and the interactions between the people of Southeast China and their environment, as well as the formation and development of agricultural civilizations in East Asia, this study focused on determining the luminescence ages of nine pottery/burnt clay samples and measuring 33 trace elements in 38 pottery/burnt clay and 15 sediment samples collected from the Minjiang River Basin. The reliability of determining luminescence age using heated quartz was also investigated. By combining the characteristics of trace elements with the background of prehistoric human environments, this study aimed to explore the relationships between humans and the environment and cultural interactions during the late Neolithic period in the Minjiang River Basin. The results showed that some pottery samples displayed a higher proportion of medium and slow components in their initial quartz optically stimulated luminescence (OSL) signals, but most OSL ages were not affected. The ages of the pottery samples were concentrated during stable environmental periods characterized by relatively high sea levels, elevated surface sea temperatures, and low El Niño–Southern Oscillation occurrence frequencies. The chemical composition and principal component analysis suggested that the majority of pottery samples were locally sourced, while pottery from coastal islands may have originated from upstream areas of the Minjiang River. This indicates that there was cultural exchange in the Minjiang River Basin during the Neolithic culture period, rather than being limited to the local living. Differences in subsistence patterns could serve as a driving force behind cross-regional cultural exchanges, which likely deepened over time. • A systematic luminescence dating of pottery in the southeast coast of China • The date of the pottery indicates that the ancient human activity was concentrated during periods of climate stability • There existed exchanges between different regional cultures in the Minjiang River Basin during the Late Neolithic and Bronze periods [ABSTRACT FROM AUTHOR]

Abstract Shell mounds are the foremost type of Neolithic sites found in coastal areas of South China. These sites can provide significant information on prehistoric human activity and climate change; however, only a few shell mounds have a systematic chronology in South China. In this study, optically stimulated luminescence (OSL) and 14C dating techniques were employed to establish a systemic chronological framework for a Neolithic shell mound found at Pingfengshan in the coastal area of Fujian Province, southern China. In addition, the possible reasons for human coastal migrations that took place during this specific period, along with their associations with climate change, are discussed. The results showed that the obtained OSL ages were reliable and consistent with the 14C chronology. The age of the Pingfengshan site was found to be approximately 4.0–3.3 ka. Additionally, it was found that post-depositional anthropogenic disturbances can have various influences on the resultant OSL and 14C ages. Cross-validation between different dating methods proved to be of great importance to adequately determine the chronology in archaeological sites. The study revealed that climatic changes played a crucial role in prehistoric human migration during the Huangguashan cultural period (4.3–3.2 ka). Sea level fluctuation may have affected onshore living space and site selection of prehistoric settlements, and intensive winter monsoons may have caused the recession of the Huangguashan culture. [ABSTRACT FROM AUTHOR]

Effective utilization of coal bed methane is very significant for energy utilization and environment protection. Catalytic combustion of methane is a promising way to eliminate trace amounts of oxygen in the coal bed methane and the key to this technology is the development of high-efficiency catalysts. Herein, we report a series of Ce1-xLaxO2-δ (x = 0–0.8) monolithic catalysts for the catalytic combustion of methane, which are prepared by citric acid method. The structural characterization shows that the substitution of La enhance the oxygen vacancy concentration and reducibility of the supports and promote the migration of the surface oxygen, as a result improve the catalytic activity of CeO2. M-Ce0.8La0.2O2-δ (monolithic catalyst, Ce0.8La0.2O2-δ coated on cordierite honeycomb) exhibits outstanding activity for methane combustion, and the temperature for 10 and 90% methane conversion are 495 and 580 °C, respectively. Additionally, Ce0.8La0.2O2-δ monolithic catalyst presents excellent stability at high temperature. These Ce1-xLaxO2-δ monolithic materials with a small amount of La incorporation therefore show promises as highly efficient solid solution catalysts for lean-oxygen methane combustion.ᅟ [ABSTRACT FROM AUTHOR]

MnSi nanoparticles on silica are prepared by metal-organic (MO)CVD of Mn(CO)5SiCl3 as a single-source precursor. Mn(CO)5SiCl3 is synthesized from Mn2(CO)10 and SiHCl3 using standard Schlenk techniques, and confirmed by Fourier transform infrared (FTIR), single-crystal X-ray diffraction (XRD), and 13C and 29Si nuclear magnetic resonance (NMR). Powder XRD patterns, high resolution transmission electron microscopy (HRTEM), elemental maps, and energy dispersive X-ray (EDX) spectroscopy show that MnSi particles, with a size of about 5-6 nm, are uniformly dispersed on the silica support. The formation mechanism of MnSi nanoparticles on silica is investigated by in-situ FTIR spectroscopy. The results demonstrate the formation details of MnSi nanoparticles from Mn(CO)5SiCl3 through the elimination of carbonyl groups and dissociation of SiCl bonds with the promotion of H2. [ABSTRACT FROM AUTHOR]

MnSi nanoparticles on silica are prepared by metal-organic (MO)CVD of Mn(CO)5SiCl3 as a single-source precursor. Mn(CO)5SiCl3 is synthesized from Mn2(CO)10 and SiHCl3 using standard Schlenk techniques, and confirmed by Fourier transform infrared (FTIR), single-crystal X-ray diffraction (XRD), and 13C and 29Si nuclear magnetic resonance (NMR). Powder XRD patterns, high resolution transmission electron microscopy (HRTEM), elemental maps, and energy dispersive X-ray (EDX) spectroscopy show that MnSi particles, with a size of about 5-6 nm, are uniformly dispersed on the silica support. The formation mechanism of MnSi nanoparticles on silica is investigated by in-situ FTIR spectroscopy. The results demonstrate the formation details of MnSi nanoparticles from Mn(CO)5SiCl3 through the elimination of carbonyl groups and dissociation of SiCl bonds with the promotion of H2. [ABSTRACT FROM AUTHOR]

Abstract: Ketamine is a non-competitive antagonist of NMDA receptors (NMDARs) commonly used as a dissociative anesthetic in many pediatric procedures. Ketamine acts primarily by blocking NMDA ligand-gated channels. Experimental studies indicate that ketamine administration used for inducing clinically relevant anesthesia can lead to neurotoxic effects, such as apoptosis, selectively on immature brain neurons. However, the underlying mechanisms remain unclear. This study used whole-cell patch-clamp recordings in an in vitro preparation of forebrain slices to analyze pharmacologically the differences in the effects of ketamine administration on the NMDAR channel activity between immature and mature neurons. NMDAR channel activity was recorded in the form of evoked NMDAR-mediated excitatory postsynaptic currents (eEPSCs) from the forebrain of both neonatal and adult rats. Results show that ketamine inhibited eEPSCs in a dose-dependent manner in both immature and mature neurons. However, at each concentration of ketamine applied to the brain slice, a more extensive inhibition could be seen in neonatal neurons than in adult neurons. Further, the blocking effect of ketamine on eEPSCs was measured during the period of 1, 3, and 6h after ketamine washout. Inhibition of eEPSCs in immature neurons was still evident 6h after washout. In contrast, the blockade of eEPSCs in mature neurons recovered completely from the inhibition by ketamine in a time-dependent manner. These results indicate that ketamine produces a greater and longer blocking effect on NMDAR channels in immature neurons than in mature neurons. This differential effect is likely to be a critical link to the higher vulnerability to ketamine-induced neurotoxicity in neurons of the developing brain. [Copyright &y& Elsevier]