Fundus photography,fundus fluorescein angiography,and optical coherence tomography of healthy cynomolgus monkey,New Zealand rabbit,Sprague Dawley rat,and BALB/c mouse retinas

Background:A variety of experimental animal models are used in basic ophthalmological research to elucidate physiological mechanisms of vision and disease pathogenesis.The choice of animal model is based on the measurability of specific parameters or structures,the applicability of clinical measurement technologies,and the similarity to human eye function.Studies of eye pathology usually compare optical parameters between a healthy and altered state,so accurate baseline assessments are critical,but few reports have comprehensively examined the normal anatomical structures and physiological functions in these models.Methods:Three cynomolgus monkeys,six New Zealand rabbits,ten Sprague Dawley(SD)rats,and BALB/c mice were examined by fundus photography(FP),fundus fluorescein angiography(FFA),and optical coherence tomography(OCT).Results:Most retinal structures of cynomolgus monkey were anatomically similar to the corresponding human structures as revealed by FP,FFA,and OCT.New Zealand rabbits have large eyeballs,but they have large optic disc and myelinated retinal nerve fibers in their retinas,and the growth pattern of retinal vessels were also different to the human retinas.Unlike monkeys and rabbits,the retinal vessels of SD rats and BALB/c mice were widely distributed and clear.The OCT performance of them were similar with human beings except the macular.Conclusions:Monkey is a good model to study changes in retinal structure associated with fundus disease,rabbits are not suitable for studies on retinal vessel diseases and optic nerve diseases,and rats and mice are good models for retinal vascular diseases.These measures will help guide the choice of model and measurement technology and reduce the number of experimental animals required.

In the Basis of Hashimoto’s Thyroiditis, to Form Papillary Thyroid Carcinoma, Metastasized and Then to De-Differentiate into Poorly Differentiated Squamous Cell Carcinoma

Thyroid squamous cell carcinoma is very rare. At present, it is limited to case reports. Since the thyroid follicular epithelium is the non-squamous epithelium, how primary squamous cell carcinoma (SCC) of the thyroid occurs is still a controversial issue. Hashimoto’s thyroiditis (HT) is considered to be an independent risk factor for thyroid cancer, under the basis of HT, how tumor cells evolve and develop to papillary thyroid carcinoma (PTC), and particularly to de-differentiate into SCC is elusive. We report a 72-year-old female patient who developed multiple subtypes of PTC on a basis of HT, and finally to de-differentiate into SCC within the local foci of lymph node metastasis. We found that there was a variety of sub-types of PTC in this patient in the background of HT. SCC was found within local lymph node metastasis. Pathomorphology, immunohistochemistry, and molecular pathology have confirmed that the SCC was derived from PTC, and then developed into poorly differentiated SCC and/or anaplastic carcinoma. We also conducted a comprehensive literature review.

Bladder Malignant Granular Cell Tumor with EP300 Gene Mutation: A Case Report and Literature Review

Background: Malignant granular cell tumor (GCT) is extremely rare. Malignant GCT with EP300 gene mutation in the bladder has not been reported in the literature. Case Presentation: We report a special case of 45-year-old female with malignant GCT of the bladder. Pathological examination showed that the mass was 11 × 11 × 4.5 cm in size, involved in the bladder’s posterior wall. Under the microscope, the tumor cells were arranged in the shape of a nest or cord to infiltrate the bladder’s wall. The tumor cells were pleomorphic, red-stained granular within the cytoplasm, with increased nuclear/cytoplasmic ratio, vacuolar nuclei, and obvious nucleoli. The tumor cells were showed obvious nuclear atypia, and the mitosis was more than 5/50HPF. Coagulative necrosis was widely showed within the tumor. Immunohistochemistry (IHC) showed that S-100, NSE, CD68, CR, α-AT, and TFE-3 were strongly positive, and the Ki-67 proliferation index was around 15%. The next-generation high throughput sequencing indicated that EP300 gene was missense mutated (c.457A > G) with 33% mutation abundance, and genes of DPYD (c.1627A > G), ERCC1 (c.354T > C), NQO1 (c.559C > T), TPMT (c.719A > G) and XRCC1 (c.1196A > G) were polymorphic mutated. The patient died after three months of the second surgical treatment. Conclusions: We report for the first time a primary bladder malignant GCM accompanied by mutations in special driving genes such as EP300. We also conducted a comprehensive literature review and an in-depth discussion.

Effects of spaceflight and simulated microgravity on microbial growth and secondary metabolism

Spaceflight and ground-based microgravity analog experiments have suggested that microgravity can affect microbial growth and metabolism. Although the effects of microgravity and its analogs on microorganisms have been studied for more than 50 years, plausible conflicting and diverse results have frequently been reported in different experiments, especially regarding microbial growth and secondary metabolism. Until now, only the responses of a few typical microbes to microgravity have been investigated; systematic studies of the genetic and phenotypic responses of these microorganisms to microgravity in space are still insufficient due to technological and logistical hurdles. The use of different test strains and secondary metabolites in these studies appears to have caused diverse and conflicting results. Moreover, subtle changes in the extracellular microenvironments around microbial cells play a key role in the diverse responses of microbial growth and secondary metabolisms. Therefore, "indirect" effects represent a reasonable pathway to explain the occurrence of these phenomena in microorganisms. This review summarizes current knowledge on the changes in microbial growth and secondary metabolism in response to spaceflight and its analogs and discusses the diverse and conflicting results. In addition, recommendations are given for future studies on the effects of microgravity in space on microbial growth and secondary metabolism.

Long-term follow-up of cumulative incidence of hepatocellular carcinoma in hepatitis B virus patients without antiviral therapy

BACKGROUND China has a high prevalence of hepatitis B virus(HBV),but most chronic hepatitis B(CHB)patients do not receive standardized antiviral therapy.There are few relevant reports addressing the outcomes of the large number of CHB patients who do not receive antiviral therapy.AIM To observe the outcomes of long-term follow-up of patients with CHB without antiviral treatment.METHODS This study included 362 patients with CHB and 96 with hepatitis B cirrhosis without antiviral treatment and with only liver protection and anti-inflammatory treatment from 1993 to 1998.The median follow-up times were 10 and 7 years,respectively.A total of 203 CHB and 129 hepatitis B cirrhosis patients receiving antiviral therapy were selected as the control groups.The median follow-up times were 8 and 7 years,respectively.Kaplan-Meier curves were used to analyze the cumulative incidence of hepatocellular carcinoma(HCC),and the Cox regression model was used to analyze the risk factors for HCC.RESULTS Among the patients in the non-antiviral group,16.9%had spontaneous decreases(HBeAg)seroconversion.In the antiviral group,87.2%of patients had undetectable HBV DNA,and 52%showed HBeAg seroconversion.Among CHB and hepatitis B cirrhosis patients,the cumulative incidence rates of HCC were 14.9%and 53.1%,respectively,in the non-antiviral group and were 10.7%and 31.9%,respectively,in the antiviral group.There was no difference between the two groups regarding the CHB patients(P=0.842),but there was a difference between the groups regarding the hepatitis B cirrhosis patients(P=0.026).The cumulative incidence rates of HCC were 1.6%and 22.3%(P=0.022)in the groups with and without spontaneous HBeAg seroconversion,respectively.The incidence rates of HCC among patients with and without spontaneous declines in HBV DNA to undetectable levels were 1.6%and 19.1%,respectively(P=0.051).There was no difference in the cumulative incidence of HCC between the two groups regarding the patients with drug-resistant CHB(P=0.119),but there was a significant difference between the two groups regarding the patients with cirrhosis(P=0.004).The Cox regression model was used for regression of the corrected REACH-B score,which showed that alanine aminotransferase>400 U/L,history of diabetes,and family history of liver cancer were risk factors for HCC among men aged>40 years(P<0.05).Multifactorial analysis showed that a family history of HCC among men was a risk factor for HCC.CONCLUSION Antiviral therapy and non-antiviral therapy with liver protection and antiinflammatory therapy can reduce the risk of HCC.Antiviral therapy may mask the spontaneous serological response of some patients during CHB.Therefore,the effect of early antiviral therapy on reducing the incidence of HCC cannot be overestimated.

Trigeminal extracranial thermocoagulation along with patientcontrolled analgesia with esketamine for refractory postherpetic neuralgia after herpes zoster ophthalmicus:A case report

BACKGROUND Primary trigeminal neuralgia can achieve satisfactory results through clinical treatment and intervention.The pathogenesis of neuralgia caused by varicellazoster virus infection of the trigeminal nerve is more complex,and it is still difficult to relieve the pain in some patients simply by drug treatment or surgical intervention.CASE SUMMARY A 66-year-old woman was hospitalized with herpetic neuralgia after herpes zoster ophthalmicus(varicella-zoster virus infects the ophthalmic branch of the trigeminal nerve).On admission,the patient showed spontaneous,electric shocklike and acupuncture-like severe pain in the left frontal parietal region,and pain could be induced by touching the herpes area.The numerical rating scale(NRS)was 9.There was no significant pain relief after pulsed radiofrequency and thermocoagulation of the ophthalmic branch of the trigeminal nerve.Combined with patient-controlled intravenous analgesia(PCIA)with esketamine,neuralgia was significantly improved.The patient had no spontaneous pain or allodynia at discharge,and the NRS score decreased to 2 points.The results of follow-up 2 mo after discharge showed that the NRS score was≤3,and the Pittsburgh Sleep Quality Index score was 5 points.There were no adverse reactions.CONCLUSION Trigeminal extracranial thermocoagulation combined with esketamine PCIA may be a feasible method for the treatment of refractory herpetic neuralgia after herpes zoster ophthalmicus.

Kinetic Model of Fixed Bed Reactor with Immobilized Microorganisms for Removing Low-Concentration SO_2

On the basis of the analysis of the process of treating low concentrations of sulfur dioxide （SO2） gas in a fixed bed reactor, a kinetic model is proposed for this process after taking into consideration the effects of internal diffusion, cell concentration, and production yield of microorganisms but ignoring the effect of external diffusion. The results obtained from the model simulation show that this model can indicate the influence of the process factors, Cin, η μmax, Cx, A, h, Kin, and Q, on the removal of SO2 and that the prediction of the results by this model is also satisfactory. This kinetic model can also provide some very important indications regarding the preparation of immobilized microorganisms, selection and domestication of proper species of microorganisms, as well as the design of bioreactors.

Metastatic low-grade endometrial stromal sarcoma with sex cord and smooth muscle differentiation: A case report

BACKGROUND Metastatic low-grade endometrial stromal sarcoma(LG-ESS) with sex cord-like and smooth muscle-like differentiation is rare. This article reports such a case with multiple recurrences and with extensive pelvic and abdominal metastasis.CASE SUMMARY A 47-year-old female patient was diagnosed with multiple cystic masses in the pelvic cavity by magnetic resonance imaging examination. Based on the postoperative pathological and immunohistochemical analyses of the surgical specimen, she was diagnosed with a metastatic low-grade endometrial stromal sarcoma with sex cord and smooth muscle differentiation.CONCLUSION LG-ESS is a low-grade malignant tumor with a high recurrence rate and metastasis probability. It is easily misdiagnosed initially. It is essential to distinguish LG-ESS with sex cord-like differentiation from uterine tumour resembling ovarian sex cord tumour.

Rescue of the albino phenotype by introducing a functional tyrosinase minigene into Kunming albino mice

AIM： To use the tyrosinase minigene as a visual marker to perform microinjection training and improve the techniques related with transgene to greatly elevate the effidency of gene transfer. METHODS： A mouse tyrosinase minigene, i.e., TyBS, in which the 2.25-kb authentic genomic 5＇ non-coding flanking sequence of mouse tyrosinase was fused to a mouse tyrosinase cDNA, was introduced into the fertilized eggs of outbred Kunming albino mice. RESULTS： Of the 11 animals that developed from the injected eggs, two mice （P1 and #8） exhibited pigmented hair （P1） and eyes （P1 and #8）, as confirmed by PCR analysis for the tyrosinase minigene integrated into the genome. When founder P1 was bred to Kunming male mouse, six progeny out of 11 offspring inherited the transgene and the pigmented-eye phenotype. CONCLUSION： Taken together, these results suggest that this minigene encodes the active tyrosinase protein and that its 5＇ flanking region contains the sequences regulating the expression of mouse tyrosinase gene as expected. We have rescued the albino phenotype by introduction and expression of a functional tyrosinase minigene in the Kunming albino mouse and the transgene can be passed to subsequent generation. These findings also indicate that TyBS can be a useful visual marker gene in the co-transgenic experiments.

Great efficacy of sulfachloropyrazine-sodium against acute murine toxoplasmosis

Objective:To identify more effective and less toxic drugs to treat animal toxoplasmosis.Methods:Efficucy of seven kinds of sulfonamides against Toxoplasma gondii(T.gondii)in an acute murine model was evaluated.The mice used throughout the study were randomly assigned to many groups(10 mice each),which either remained uninfected or were infected intraperitoneally with lachyzoites of T.gondii(strains RH and CN).All groups were then treated with different sulfonamides and the optimal treatment protocol was determined candidates.Sulfadiazine-sodium(SD)was used for comparison.Results:The oplimal therapy involved gavaging mice twice per day with 250 mg/kg bw of sulfachloropyrazine-sodium(SPZ)for five days.Using this protocol,the average survival time and the time-point of 50%fatalities were prolonged significantly compared with SD treatment.Treatment with SFZ protected 40%of mice from death,and the heart and kidney tissue of these animals was parasite-free,as determined by nestedPCK.SPZ showed excellent therapeutic effects in the treatment of T.gondii in an acute murine model and is therefore a promising drug candidate for the treatment and prevention of T.gondii in animals.Conclusions:It can be concluded that the effective drug sulfachloropyrazine may be the new therapeutic options against animal toxoplasmosis.

Influence of different Fe doping strategies on modulating active sites and oxygen reduction reaction performance of Fe, N-doped carbonaceous catalysts

Fe/N/C catalysts,synthesized through the pyrolysis of Fe-doped metal–organic framework (MOF) precursors,have attracted extensive attention owing to their promising oxygen reduction reaction (ORR) catalytic activity in fuel cells and/or metal-air batteries.However,post-treatments (acid washing,second pyrolysis,and so on) are unavoidable to improve ORR catalytic activity and stability.The method for introducing Fe^(3+) sources (anhydrous Fe Cl_(3)) into the MOF structure,in particular,is a critical step that can avoid time-consuming post-treatments and result in more exposed Fe-N_(x) active sites.Herein,three different Fe doping strategies were systematically investigated to explore their influence on the types of active sites formed and ORR performance.Fe-NC(Zn^(2+)),synthesized by one-step pyrolysis of Fe doped ZIF-8 (Zn^(2+)) precursor which was obtained by adding the anhydrous Fe Cl_(3)source into the Zn(NO_(3))_(2)·6H_(2)O/methanol solution before mixing,possessed the highest Fe-N_(x)active sites due to the high-efficiency substitution of Zn^(2+)ions with Fe^(3+) ions during ZIF-8 growth,the strong interaction between Fe^(3+) ions and N atoms of 2-Methylimidazole (2-MIm),and ZIF-8’s micropore confinement effect.As a result,Fe-NC(Zn^(2+)) presented high ORR activity in the entire p H range (p H=1,7,and 13).At p H=13,Fe-NC(Zn^(2+)) exhibited a half-wave potential (E1/2) of 0.95 V (vs.reversible hydrogen electrode),which was 70 m V higher than that of commercial Pt/C.More importantly,Fe-NC(Zn^(2+)) showed superior ORR stability in neutral media without performance loss after 5,000 cycles.A record-high open-circuit voltage(1.9 V) was obtained when Fe-NC(Zn^(2+)) was used as a cathodic catalyst in assembled Mg-air batteries in neutral media.The assembled liquid and all-solid Mg-air batteries with high performance indicated that Fe-NC(Zn^(2+)) has enormous potential for use in flexible and wearable Mg-air batteries.

Pre-fixing defects in carbon framework for revealing the active sites of oxygen reduction reaction at nitrogen-doped carbon nanotubes

Nitrogen-doped carbon-based materials are promising non-platinum group metal electrocatalysts for the oxygen reduction reaction(ORR).Understanding their ORR active sites is vital for the rational design and development of nitrogen-doped carbon-based electrocatalysts with enhanced catalytic efficiency and selectivity.However,the conclusive analysis of the ORR mechanism of nitrogen-doped carbon-based electrocatalysts remains a grand challenge because the catalysts have a complex inhomogeneous structure.Here,we elucidate this problem using nitrogen-doped carbon nanotubes framework catalysts with fixed defect concentrations prepared by pre-thermal treatment at a low temperature.The generation of defects under high-temperature treatment was effectively suppressed to enable a simple model for ORR mechanism study.A correlation between ORR pathways and the different nitrogen species in the nitrogen-doped carbon catalysts was revealed through a combination of structural and electrochemical properties investigations.Besides,our results also demonstrate the importance of defects for ORR.We believe that the results will provide instructive guidance for designing and developing novel carbon nanomaterials for ORR.

新师范教育背景下化学(师范类)专业建设探索与实践——以盐城师范学院为例

在新师范教育背景下,盐城师范学院化学(师范类)专业以普通高等学校师范类专业认证和一流本科专业建设为抓手,强化新师范教育内涵建设,形成了鲜明的专业特色和优势。本文从专业特色、师范类专业认证、综合改革等方面梳理了一流师范类专业建设的路径和成效,并对专业建设进行反思,指出需要持续改进的方向。

Universal Theory and Basic Rules of Strain-Dependent Doping Behaviors in Semiconductors

Enhancing the dopability of semiconductors via strain engineering is critical to improving their functionalities,which is,however,largely hindered by the lack of basic rules.In this study,for the first time,we develop a universal theory to understand the total energy changes of point defects(or dopants)with different charge states under strains,which can exhibit either parabolic or superlinear behaviors,determined by the size of defect-induced local volume change(ΔV).In general,ΔV increases(decreases)when an electron is added(removed)to(from)the defect site.Consequently,in terms of this universal theory,three basic rules can be obtained to further understand or predict the diverse strain-dependent doping behaviors,i.e.,defect formation energies,charge-state transition levels,and Fermi pinning levels,in semiconductors.These three basic rules could be generally applied to improve the doping performance or overcome the doping bottlenecks in various semiconductors.

High expression of hepatitis B virus based vector with reporter gene in hepatitis B virus infection system

AIM: To construct a hepatitis B virus (HBV)-based vector with a reporter gene and to establish an HBV infection system to evaluate the availability of the vector. METHODS: The HBV-based vectors with green fluorescence protein (GFP) were packaged into the liver of immunodeficient mice through transfer and helper plasmid using hydrodynamic technology. Wild type HBV (wt HBV) was provided by plasmid MC2009. Primary human hepatocytes (PHH) were isolated and infected with recombinant HBV (rHBV) or wt HBV. GFP expression was monitored by confocal and flow cytometry. HBV DNA and HBV surface antigen (HBSAg) were analyzed by PCR and ELISA. RESULTS: 3 × 107 wt HBV copies/mL and 5 × 106 rHBV copies/mL were collected from mice serum. In the wt HBV infected group, HBV progeny was 2 × 107 copies/mL and HBSAg was 770 ng/mL. In the rHBV infected group, GFP fluorescence was detected on d 3 post-infection and over 85% of the parenchymal cells expressed green fluorescence on d 12 post-infection. Compared with wt HBV in the PHH infection system, no rHBV DNA or HBSAg were detected in PHH culture media. CONCLUSION: An effective HBV based vector was developed, which proved to be a useful HBV infection system. This vector and infection system can be applied to develop a therapeutic vector and study the HBV life cycle and viral pathogenesis.

Consistent Riccati expansion solvability,symmetries,and analytic solutions of a forced variable-coefficient extended Korteveg-de Vries equation in fluid dynamics of internal solitary waves

We study a forced variable-coefficient extended Korteweg-de Vries(KdV)equation in fluid dynamics with respect to internal solitary wave.Bäcklund transformations of the forced variable-coefficient extended KdV equation are demonstrated with the help of truncated Painlevéexpansion.When the variable coefficients are time-periodic,the wave function evolves periodically over time.Symmetry calculation shows that the forced variable-coefficient extended KdV equation is invariant under the Galilean transformations and the scaling transformations.One-parameter group transformations and one-parameter subgroup invariant solutions are presented.Cnoidal wave solutions and solitary wave solutions of the forced variable-coefficient extended KdV equation are obtained by means of function expansion method.The consistent Riccati expansion(CRE)solvability of the forced variable-coefficient extended KdV equation is proved by means of CRE.Interaction phenomenon between cnoidal waves and solitary waves can be observed.Besides,the interaction waveform changes with the parameters.When the variable parameters are functions of time,the interaction waveform will be not regular and smooth.

False esophageal hiatus hernia caused by a foreign body: A fatal event

Foreign body ingestion is a common complaint in gastrointestinal clinics. It is usually not difficult to diagnose because most of the patients report a definitive history of accidental foreign body ingestion. However, in rare cases, patients do not have a clear history. Thus, the actual condition of the patient is difficult to diagnosis or is misdiagnosed; consequently, treatment is delayed or the wrong treatment is administered, respectively. This report describes a fatal case of esophageal perforation caused by an unknowingly ingested fishbone, which resulted in lower esophageal necrosis, chest cavity infection, posterior mediastinum fester, and significant upper gastrointestinal accumulation of blood. However, his clinical symptoms and imaging data are very similar with esophageal hiatal hernia. Unfortunately, because the patient was too late in consulting a physician, he finally died of chest infection and hemorrhage caused by thoracic aortic rupture. First, this case report underlines the importance of immediate consultation with a physician as soon as symptoms are experienced so as not to delay diagnosis and treatment, and thus avoid a fatal outcome. Second, diagnostic imaging should be performed in the early stage, without interference by clinical judgment. Third, when computed tomography reveals esophageal hiatus hernia with stomach incarceration, posterior mediastinal hematoma, and pneumatosis caused by esophageal, a foreign body should be suspected. Finally, medical professionals are responsible for making people aware of the danger of foreign body ingestion, especially among children, those who abuse alcohol, and those who wear dentures, particularly among the elderly, whose discriminability of foreign bodies is decreased, to avoid dire consequences.

Differentiation of human epidermis-derived mesenchymal stem cell-like pluripotent cells into neural-like cells in culture and after transplantation

Skin is the largest organ of the human body and a possible source of stem cells for research and cell-based therapy. We have isolated a population of mesenchymal stem cell-like pluripotent cells from human epidermis, termed human (h) EMSCPCs. This preliminary study tested if these hEMSCPCs can be induced to differentiate into neural-like cells. Human EMSCPCs were first cultured for four to seven days in a serum-free neural stem cell (NSC) medium for pre-induction. During pre-induction, hEMSCPCs coalesced into dense spheres that resembled neural rosettes. In the presence of a conditioned differentiation medium, pre-induced cells took on the morphological characteristics of neural cells, including slender projections with inflated or claw-like ends that contacted the soma or projections of other cells as revealed by confocal microscopy. Moreover, these differentiating cells expressed the neural-specific markers β-III tubulin, MAP2, GFAP, and synapsin I as evidenced by immunocytochemistry. Both pre-induced hEMSCPCs and uninduced hEMSCPCs were labeled with CM-DiI and transplanted into the vitreous cavities of nude mice. Transplanted cells were examined four weeks later in frozen eyeball sections by immunofluorescence staining, which demonstrated superior retinal migration and neural differentiation of pre-induced cells. Our study is the first to demonstrate that hEMSCPCs possess the capacity to differentiate into neural-like cells, suggesting potential uses for the treatment of retinal diseases such as age-related macular degeneration.

Silurian integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

The Silurian palaeontology and stratigraphy of the Qinghai-Tibetan Plateau have been studied for more than100 years.With the launch of the Second Tibetan Plateau Scientific Expedition and Research,it is necessary to update the summaries of the Silurian stratigraphy and fossil assemblages of the Qinghai-Tibetan Plateau and their correlation with its surrounding areas.In this study,we have selected 33 sections from the Qinghai-Tibetan Plateau and its surroundings areas,summarised the available data in terms of stratigraphic regionalisation,lithostratigraphy,chronostratigraphy,and biostratigraphy,and divided the study area into four stratigraphic provinces:the Xizang-Western Yunnan-Western Sichuan Province,the KunlunQilian Province,the South China Province,and the Tarim Province.In general,the Silurian strata in the Qinghai-Tibetan Plateau is more complete than those in other areas of China.Palaeobiogeographical studies of the vertebrate faunas,sporomorph assemblages,and brachiopod faunas of the study area indicate a closer geographical relationship between the South China,Tarim,and Indochina palaeoplates,than previously considered.Compared with the surrounding areas where Silurian strata have been extensively studied,the study of Silurian strata in the main part of the Qinghai-Tibetan Plateau is still in the preliminary stage.In the future,it is necessary to conduct research on the age,distribution,and resource potential of basal Silurian black shales to provide new directions for shale gas exploration and development in China.The shallow marine strata of the middle to upper Silurian require further subdivision.Considering that the Silurian System in the Qinghai-Tibetan Plateau is more complete,it has the potential to supplement and improve the study of the carbon isotope stratigraphy of the Silurian in China.

Optimal SOC Headroom of Pump Storage Hydropower for Maximizing Joint Revenue from Day-ahead and Real-time Markets Under Regional Transmission Organization Dispatch

In response to the increasing penetration of volatile and uncertain renewable energy,the regional transmission organizations(RTOs)have been recently focusing on enhancing the models of pump storage hydropower(PSH)plants,which are one of the key flexibility assets in the day-ahead(DA)and real-time(RT)markets,to further boost their flexibility provision potentials.Inspired by the recent research works that explored the potential benefits of excluding PSHs’cost-related terms from the objective functions of the DA market clearing model,this paper completes a rolling RT market scheme that is compatible with the DA market.Then,with the vision that PSHs could be permitted to submit state-of-charge(SOC)headrooms in the DA market and to release them in the RT market,this paper uncovers that PSHs could increase the total revenues from the two markets by optimizing their SOC headrooms,assisted by the proposed tri-level optimal SOC headroom model.Specifically,in the proposed tri-level model,the middle and lower levels respectively mimic the DA and RT scheduling processes of PSHs,and the upper level determines the optimal headrooms to be submitted to the RTO for maximizing the total revenue from the two markets.Numerical case studies quantify the profitability of the optimal SOC headroom submissions as well as the associated financial risks.