Establishment of an astronomical time scale for the Shizigou Formation in the Qaidam Basin,Inner Asia and orbital forced evolution of lakes during The Pliocene

The Qaidam Basin,as the largest inland basin within the Tibetan Plateau,has accumulated more than 10,000 m of Cenozoic continental sediments.It serves as a crucial research area for documenting Cenozoic climate changes and plateau uplift processes in the Asian interior.Additionally,the basin holds vast reserves of oil and gas resources,making high-resolution drilling data invaluable for studying paleoclimate.In this study,the longsequence lacustrine deposits of JS1 drill core across the Shizigou Formation in the Yiliping Depression at the western center of the basin were studied,aiming to establish an astronomical timescale for the Shizigou Formation and investigate the characteristics of paleoclimatic changes during the late Miocene to the Pliocene for the Asian interior.The analysis was carried out using high-resolution natural gamma ray(GR)data sequences,employing techniques such as spectral analysis,filtering,and wavelet analysis in cyclostratigraphy.The results indicated the presence of a stable Milankovitch orbital signal was perfectly recorded in the Shizigou Formation,primarily influenced by eccentricity cycles,with weaker obliquity and precession cycles.Using the stable and continuous 405 ka eccentricity cycle in astronomical tuning,a"floating"astronomical timescale with a duration of 6.1 Ma for the Yiliping depression's Shizigou Formation has been established.With reference to previously established stratigraphic age anchor points,an absolute astronomical timescale(2.5–8.6 Ma)has been ultimately provided for the Shizigou Formation.Simultaneously,a clear 100 ka short eccentricity cycle record has been identified during the Pliocene(5.3–2.5 Ma),which corresponds in time with the aridification within the basin during this Pliocene period.In addition,a comparison of the Pliocene natural gamma ray curve of the Qaidam Basin with global ice volume variations indicated that the basin's aridification was influenced by global cooling,with eccentricity-modulated precession cycles controlling solar radiation and subsequently affecting the evolution of lakes in the arid region of Inner Asia.

Progress of Research on the Effect of Dietary Care on Patients with Gastritis and Gastric Ulcers

Gastritis gastric ulcer is a common disease of the digestive system,which has a serious impact on the quality of life and health of affected individuals.Dietary care is one of the important measures to treat and prevent gastritis gastric ulcers.This paper reviews the research progress on the impact of dietary care on patients with gastritis and gastric ulcers,including dietary behavioral intervention,dietary habit cultivation,dietary hygiene education,and nutritional support.Studies have shown that rational dietary care was able to improve the clinical symptoms of patients,regulate the intestinal microbial community,anti-inflammatory,antioxidant,and other pathways to improve the pathophysiological state of patients with gastritis and gastric ulcer and prevent recurrence.Therefore,dietary care is of great significance to patients with gastritis and gastric ulcers.

Eliminating Explicit Contention from Channel Access in Distributed Wireless Networks

Emerging techniques such as WiFi direct makes the objective of always-on be true. People can easily chat and share files with nearby friends even without AP(Access Point) or cellular coverage. In this paper, we focus on the channel efficiency issue of APfree Wi-Fi networks, which can be easily constructed in the subway, in a high-speed railway, or when camping in the wild. Today IEEE 802.11 DCF is the most commonly used MAC protocol for Wi-Fi networks, however, due to the control messages and backoff time, channel efficiency in high data rate networks can be extremely low. To solve this, we propose CD-MAC, which allows control messages to be transmitted with data packets concurrently, and thus eliminates the overheads of backoff and explicit contention. To maintain the reception reliability, we redesign the control messages and use signal detection in PHY instead of bits decoding to detect them. In MAC layer, CD-MAC is built upon our Correlation Detection based PHY. We have implemented and evaluated CD-MAC using USRP N210. Evaluation results show that CD-MAC can achieve over 95.5% channel efficiency and provide throughput gains of up to 80%, 60%, and 29.1% compared with DCF, 802.11 ec, and back2F, respectively.

Association between serum levels of TSH and free T4 and per- and polyfluoroalkyl compounds concentrations in pregnant women

Many per-and polyfluoralkyl substances(PFASs)may disrupt maternal thyroid hormone homeostasis in pregnancy.Concerns should be raised regarding the PFASs exposure in pregnant women because thyroid hormones are involved in the early development of the fetus.In this study,we measured the concentrations of 13 PFASs,including five novel shortchain PFASs,in serum from 123 pregnant women in Beijing,China.Linear regression models were used to investigate the association between thyroid-stimulating hormone(TSH)or free thyroxine(FT4)levels and PFASs concentrations under consideration of the impacts of pregnancy-induced physiological factors.We found that perfluorobutanoic acid(PFBA)(β=0.189,95%CI=-0.039,0.417,p=0.10)and perfluorodecanoic acid(PFDA)(β=-0.554,95%CI=-1.16,0.049,p=0.071)were suggestive of significant association with TSH in thyroid peroxidase antibody(TPOAb)negative women.No association was observed between all PFASs and FT4 levels after controlling for these confounding factors,such as BMI,gestational weight gain and maternal age.These findings suggest that it should pay more attention to the association between thyroid hormone levels and short-chain PFASs concentrations.Future studies could consider a greater sample and the inclusion of other clinical indicators of thyroid function,such as free T3 and total T3.

Heavy metals in maternal and cord blood in Beijing and their efficiency of placental transfer

This study aimed to determine the effect of exposure to heavy metals in pregnant women in Beijing, China. We also evaluated the association of these heavy metals with birth weight and length of newborns. We measured the levels of 10 heavy metals,including lead(Pb), titanium(Ti), manganese(Mn), nickel(Ni), cadmium(Cd), chromium(Cr), antimony(Sb), stannum(Sn), vanadium(V), and arsenic(As), in 156 maternal and cord blood pairs. An inductively coupled plasma mass spectrometry method was used for measurement. Pb, As, Ti, Mn, and Sb showed high detection rates(> 50%) in both maternal and cord blood. Fourteen(9%) mothers had blood Pb levels greater than the United States Center for Disease Control allowable threshold limit for children(50 μg/L).In prenatal exposure to these heavy metals, there was no significant association between any heavy metal and birth weight/length. Moreover, we estimated the placental transfer efficiency of each heavy metal, and the median placental transfer efficiency ranged from 49.6%(Ni) to 194%(Mn)(except for Cd and Sn). The level and detection rate of Cd in maternal blood were much higher than that in cord blood, which suggested that Cd had difficulty in passing the placental barrier. Prospective research should focus on the source and risk of heavy metals in non-occupationally exposed pregnant women in Beijing.