Interconnectivity in the Region of Eurasia:Mongolia’s Presence in the SCO(Shanghai Cooperation Organization)

The Shanghai Cooperation Organization(SCO)was formed in 2001 after breakdown of the socialist system and the Soviet Union as a new form of cooperation between former socialist countries in Eurasian region.Mongolia joined the SCO in 2005 with an observer member status.Since 2007,Presidents of Mongolia began to participate every year to the Summit of the heads of SCO member states.By the initiative of Mongolian President,in 2014 the tripartite format of the meetings of the leaders of three countries:Russia,China,and Mongolia were established.In June 2016,during the third meeting of the leaders of Russia,China,and Mongolia in Tashkent(Uzbekistan),“The Russia-China-Mongolia Economic Corridor Program”document was signed.This program is aiming to develop the infrastructure of three countries,ensuring the competitiveness of products on the world market,and strengthening the Eurasian integration.The content of this program is combining the main ideas of Chinese“Belt-Road”megaproject,Russian initiative for developing of Eurasian economic integration and Mongolian“Steppe Road”project.The main goal of the“Steppe Road”initiative is to involve Mongolia to become the transit territory for transportation of natural gas,oil,and other products between Russia and China.In conclusion,the author gives some comments regarding the issue of full membership status of Mongolia to the international organization—SCO.

Analysis Methods for the Determination of Anthropogenic Additions of P to Agricultural Soils

Phosphorus loading and measurement is of concern on lands where biosolids have been applied. Traditional soil testing for plant-available P may be inadequate for the accurate assessment of P loadings in a regulatory environment as the reported levels may not correlate well with environmental risk. In order to accurately assess potential P runoff and leaching, as well as plant uptake, we must be able to measure organic P mineralized by the biotic community in the soil. Soils with varying rates of biosolid application were evaluated for mineralized organic P during a 112-day incubation using the difference between P measured using a rapid-flow analyzer (RFA) and an axial flow Varian ICP-OES. An increase in the P mineralized from the treated soils was observed from analysis with the Varian ICP-OES, but not with the RFA. These results confirm that even though organic P concentrations have increased due to increasing biosolid application, traditional soil testing using an RFA for detection, would not accurately portray P concentration and potential P loading from treated soils.

“I am willing to play a proactive role in China-Russia Scientific Research Exchanges”——Exclusive Interview with Dr. Konstantin Chingin, the awardee of 2018 Chinese Government Friendship Award

Professor Konstantin Chingin is engaged in the research of direct mass spectrum analysis in terms of basic theories,instrument development and applications and has achieved plenty of original results. He has done a lot in the fields of scientific research, platform construction。

Using self-determination theory to identify organizational interventions to support coal mineworkers’ dust-reducing practices

Advancing the application of safety and health(S&H)technologies is likely to remain a value in the mining industry.However,any information that technologies generate must be translated from the organization to the workforce in a targeted way to result in sustainable change.Using a case study approach with continuous personal dust monitors(CPDMs),this paper argues for an organizational focus on technology integration.Although CPDMs provide mineworkers with near real-time feedback about their respirable coal dust exposure,they do not ensure that workers or the organization will continuously use the information to learn about and reduce exposure sources.This study used self-determination theory(SDT)to help three mines manage and communicate about information learned from the CPDM technology.Specifically,35 mineworkers participated in two mixed-method data collection efforts to discuss why they do or do not use CPDMs to engage in dust-reducing practices.Subsequently,the data was analyzed to better understand how organizations can improve the integration of technology through their management systems.Results indicate that using the CPDM to reduce sources of dust exposure is consistent with mineworkers’self-values to protect their health and not necessarily because of compliance to a manager or mine.

The Diagnostic and Prognostic Value of Serum Procalcitonin among Ventilator Associated Pneumonia Patients

Ventilator-associated pneumonia (VAP) is a complication in as many as 28% of patients who receive mechanical ventilation. Studies have consistently shown that a delay in diagnosis and treatment increases the mortality risk. The aim of this work was to clarify the role of the serum procalcitonin (PCT) in the diagnosis and the prognosis of ventilator associated pneumonia. Methods: Forty two VAP patients, 20 non VAP-ICU (on mechanical ventilation) admitted patients and 20 healthy control subjects of similar age and sex were included in the study. PCT levels in serum samples were measured in all subjects. Results: There was a highly statistically significant difference (p value 0.001) between VAP patients on one side and non VAP-ICU patients and healthy control subjects on the other side regarding the mean values of PCT. Also, the mean values of PCT were statistically significantly higher (p 0.001) among died VAP group than the survivor VAP group. There was a statistically positive correlation (p = 0.449), CRIP (R = 0.403) and SOFA (R = 0.437)) and initial PCT serum levels. Conclusions: This study found that the increased PCT serum level is an important diagnostic tool for VAP and the PCT serum levels can predict the outcome of VAP patients. We recommend other larger studies to augment our findings.

Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease

Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut microbiota.The aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease development.To do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of age.Twelve-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 mice.Notably,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 mice.These findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies.

How Software Engineering Transforms Organizations: An Open and Qualitative Study on the Organizational Objectives and Motivations in Agile Transformations

Agile Transformations are challenging processes for organizations that look to extend the benefits of Agile philosophy and methods beyond software engineering.Despite the impact of these transformations on orga-nizations,they have not been extensively studied in academia.We conducted a study grounded in workshops and interviews with 99 participants from 30 organizations,including organizations undergoing transformations(“final organizations”)and companies supporting these processes(“consultants”).The study aims to understand the motivations,objectives,and factors driving and challenging these transformations.Over 700 responses were collected to the question and categorized into 32 objectives.The findings show that organizations primarily aim to achieve customer centricity and adaptability,both with 8%of the mentions.Other primary important objectives,with above 4%of mentions,include alignment of goals,lean delivery,sustainable processes,and a flatter,more team-based organizational structure.We also detect discrepancies in perspectives between the objectives identified by the two kinds of organizations and the existing agile literature and models.This misalignment highlights the need for practitioners to understand with the practical realities the organizations face.

Medical errors, infection-control breaches and the use of adulterated and misbranded medical devices

Several well-publicized cases of improper cleaning,disinfection or sterilization of contaminated reusable medical equipment that posed an increased risk of patientto-patient disease transmission were reported within the past few years,resulting in the notification of approximately 20 000 patients.These medical errors,the specific infection-control standards they breached,and assessments of the risk of infection associated with each are discussed.Other topics discussed include the Food and Drug Administration’s(FDA)regulation of medical devices and infection-control products;the use of adulterated,misbranded,and investigational devices;consent decrees and associated Certificates of Medical Necessity;and informed patient consent.Focus is placed on liquid chemical sterilization,its history,and the FDA’s recent censure and discontinuation of a medical device labeled with this claim,namely,the STERIS System 1 processor.Recommendations are provided for healthcare facilities,regulatory agencies,manufacturers of reusable medical devices,and professional healthcare organizations and administrations to improve public health and prevent healthcareassociated infections.

Evaluation and Analysis of Hospital Disaster Preparedness in Jeddah

Introduction: Disaster damage to health systems is a human and health tragedy, results in huge economic losses, deals devastating blows to development goals, and shakes social confidence. Hospital disaster preparedness presents complex clinical operation. It is difficult philosophical challenge. It is difficult to determine how much time, money, and effort should be spent in preparing for an event that may not occur. Health facilities whether hospitals or rural health clinics, should be a source of strength during emergencies and disasters. They should be ready to save lives and to continue providing essential emergencies and disasters. Jeddah has relatively a level of disaster risk which is attributable to its geographical location, climate variability, topography, etc. This study investigates the hospital disaster preparedness (HDP) in Jeddah. Methods: Questionnaire was designed according to five Likert scales. It was divided into eight fields of 33 indicators: structure, architectural and furnishings, lifeline facilities’ safety, hospital location, utilities maintenance, surge capacity, emergency and disaster plan, and control of communication and coordination. Sample of six hospitals participated in the study and rated to the extent of disaster preparedness for each hospital disaster preparedness indicators. Two hazard tools were used to find out the hazards for each hospital. An assessment tool was designed to monitor progress and effectiveness of the hospitals’ improvement. Weakness was found in HDP level in the surveyed hospitals. Disaster mitigation needs more action including: risk assessment, structural and non-structural prevention, and preparedness for contingency planning and warning and evacuation. Conclusion: The finding shows that hospitals included in this study have tools and indicators in hospital preparedness but with lack of training and management during disaster. So the research shed light on hospital disaster preparedness. Considering the importance of preparedness in disaster, it is necessary for hospitals to understand that most of hospital disaster preparedness is built in the hospital system.

Gastric autoimmune disorders in patients with chronic hepatitis C before,during and after interferon-alpha therapy

AIM:To explore the prevalence of autoimmune gastritis in chronic hepatitis C virus (HCV) patients and the influence of α-interferon (IFN) treatment on autoimmune gastritis. METHODS:We performed a prospective study on 189 patients with positive anti-HCV and viral RNA enrolled in a 12-month IFN protocol.We evaluated:a) the baseline prevalence of autoimmune gastritis,b) the impact of IFN treatment on development of biochemical signs of autoimmune gastritis (at 3,6 and 12 months),c) the evolution after IFN withdrawal (12 months) in terms of anti-gastric-parietal-cell antibodies (APCA),gastrin,anti-thyroid,and anti-non-organ- specific antibodies. RESULTS:APCA positivity and 3-fold gastrin levels were detected in 3 (1.6%) and 9 (5%) patients,respectively,at baseline,in 25 (13%) and 31 (16%) patients at the end of treatment (both P<0.001,vs baseline),and in 7 (4%) and 14 (7%) patients 12 months after withdrawal (P=0.002 and P=0.01 respectively,vs baseline;P=not significant vs end of treatment).The development of autoimmune gastritis was strictly associated with the presence of autoimmune thyroiditis (P=0.0001),no relationship was found with other markers of autoimmunity. CONCLUSION:In HCV patients,IFN frequently precipitates latent autoimmune gastritis,particularly in females.Following our 12-month protocol,the phenomenon generally regressed.Since APCA positivity and high gastrin levels are associated with the presence of antithyroid antibodies, development of autoimmune thyroiditis during IFN treatment may provide a surrogate preliminary indicator of possible autoimmune gastritis to limit the need for invasive examinations.

Associations with Organ Involvement and Autoantibodies in Systemic Sclerosis: Results from the Canadian Scleroderma Research Group (CSRG)

Objective: Serum from SSc patients was analyzed centrally to determine ANA patterns and extractable nuclear antigens (ENAs) between lcSSc and dcSSc and associations with organ involvement. Methods: 1145 SSc patients had ANA and ENA analyzed by indirect immunofluorescence on HEp-2 substrate at a screening serum dilution of 1/160. Most ENA antibodies [Sm. U1-RNP, Ro52, SS-A/Ro60, topoisomeraseI (Topo1), SS-B/La, chromatin, ribosomal P and Jo1] were measured by laser bead immunoassay;and RNA polymerase III (RNAP) by ELISA. Results: ANA was positive in 95% (same in lcSSc, and dcSSc). Centromere pattern was present in 34%, speckled 22%, nucleolar 18%, homogeneous and speckled (H&S) 16%, multiple nuclear dots 6%. Anti-centromere Ab (ACA) occurred in 46% of lcSSc and 11% of dcSSc (P = 0.0001). ENAs that differed between lcSSc and dcSSc subsets were Topo1 (OR 2.4, P = 0.0001) and RNAP (OR 5.6, P 0.0001) more common in dcSSc. Overall, 15% had positive Topo1;usually with a H&S pattern (67%);Topo1 was associated with ILD on CXR (OR 2.3;95% CI 1.5 - 3.5) and HRCT (OR 3.8;95% CI 1.8 - 8.2). RNAP occurred in 18.5% (35.4% in dcSSc vs. 8.9% in lcSSc). Scleroderma renal crisis (SRC) was 13 times more likely if RNAP positive;P = 0.0001. ACA was only weakly associated with sPAP > 50 mmHg (OR 1.8;95%CI 1.1 - 3.0). Conclusion: ANA homogeneous pattern alone is rare in SSc;ACA was significantly more common in lcSSc. Many ENAs are equal in lcSSc and dcSSc except RNAP and Topo1. RNAP has the highest OR of SRC. Topo1 is less strongly associated with ILD. Abstract word count: 249, Body word count 1246, Figures 2, Tables 2. Key Messages: 1) 95% of SSc has a positive ANA and ANA patterns in SSc include centromere, nucleolar, and homogeneous and speckled together;2) Most ENAs are equal in both dcSSc and lcSSc except anti RNA polymerase III and topoisomerase I;3) RNA polymerase III has the highest association (odds ratio) with scleroderma renal crisis, topoisomerase I is associated with interstitial lung disease;whereas anticentromere was not associated with elevated pulmonary arterial pressures on echocardiogram.

Spatial Organization of Innovation in the Oil Equipment Manufacturing Industry: Case of Dongying, China

As innovation and technological change have become increasingly important for the competitiveness and sustainable growth of firms,cooperative innovation is now crucial for traditional industries in the context of globalization.This paper proposes a framework for analyzing the spatial pattern of cooperative innovation for traditional industries in developing countries.Based on in-depth interviews with 35 firms in the oil equipment manufacturing industry in Dongying City,China,this study argues that different firms in the innovation pyramid have various innovation activity preferences and spatial patterns.Firms with high innovation abilities tend to cooperate with various partners that are geographically dispersed and continuously expanding,while firms with inferior abilities usually cooperate with nearby fixed partners.Due to the differences in innovation environment and actor locations,firms tend to make different choices regarding innovation types and models,which highlight the importance of personnel training and basic scientific research at the global scale and practical product research and development at the national scale.Additionally,talent flow is the most important way to realize relationships for firm innovation activity.

Multilevel analysis of the central-peripheral-target organ pathway:contributing to recovery after peripheral nerve injury

Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and disabilities.Research on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target organs.This has led to restrictions on current therapeutic approaches.In this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target organs.After peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal cord.The nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury site.Corresponding damage to target organs can occur,including skeletal muscle atrophy and sensory receptor disruption.We then provide a brief review of the research advances in therapeutic approaches to peripheral nerve injury.The main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical exercise.However,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ pathway.Therefore,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery.

Distribution, residence time, autotrophic production, and heterotrophic removal of DOP in the Mirs Bay, northern South China Sea

The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeochemistry of DOP is in its infancy. In the present study, monthly data between 2000 and 2014 were used to analyze the temporal and spatial distributions of DOP in the Mir Bay, the northern South China Sea. The DOP residence time(TDOP) was also investigated using a simple regression analysis in combination with chlorophyll a(Chl a) measurements while excess DOP(ΔDOP), produced by the biogeochemical processes of autotrophic production and heterotrophic removal, was determined using a two-component mixing mass-balance model in combination with salinity measurements. The results showed that the DOP concentration was(0.017±0.010) mg/L higher in the surface-water compared with the bottom-water and higher in the inner Tolo Harbour and waters adjacent to Shatoujiao compared with the main zone of the bay. Although seasonal changes and annual variability in the DOP were small, the surface DOP concentration was higher in the wet season(April–September)than in the dry season(October–March) due to the impacts of seaward discharges and atmospheric deposition into the bay. Measurement and regression results showed that the DOP release rate from phytoplankton production was about 1.83(gP)/(gChl a) and the TDOP was about 7 d, which implied that the DOP cycle in the bay was rapid. The ΔDOP was calculated from the model to be about 0.000 mg/L in the main zone of the bay and about 0.002 mg/L in the inner Tolo Harbour and waters adjacent to Shaotoujiao, suggesting that the autotrophic production of DOP was almost balanced by the heterotrophic removal in the main zone of the bay and dominated in the inner Tolo Harbour and waters adjacent to Shaotoujiao. In conclusion, the Mirs Bay is very productive and fairly heterotrophic.

坡耕地土壤有机碳再分布特征及其迁移累积平衡

利用137Cs和飞灰示踪技术,研究坡耕地黑土近50年和近100年来土壤再分布过程,计算坡耕地土壤有机碳(SOC)迁移和累积平衡。结果表明:利用SOC的深度分布特征鉴定坡脚和坡足原始埋藏土壤的表面分别位于地表下70和80cm,其埋藏层的SOC含量分别比与其接壤的上覆土层SOC含量高5.2和0.4gkg。坡顶、坡肩和坡背均遭受侵蚀,年平均侵蚀的土壤厚度为0.2、5.0和2.2mmyr。坡脚和坡足部位飞灰到达的深度分别为70和80cm,与埋藏层表面相吻合。坡脚飞灰出现于埋藏A层之中,表明沉积区在蒸汽机车开始使用前已被开垦为农田(或已有侵蚀和堆积发生)。根据137Cs和飞灰分布深度构建了不同年代的坡型,结果表明侵蚀部位剥蚀的土壤多堆积在坡脚和坡足,且搬运的土壤物质先累积于坡脚,随着景观坡度变缓,土壤累积逐渐向坡足过渡。研究区(1m宽)坡顶、坡肩和坡背近百年来由于土壤侵蚀共失去683kgSOC,其中60%(418kgSOC)沉积在坡脚和坡足等低洼部位,其中有257kgSOC是近50年累积的。

Economic evaluation of the hepatitis C elimination strategy in Greece in the era of affordable direct-acting antivirals

BACKGROUND Hepatitis C virus(HCV) is a leading cause of worldwide liver-related morbidity and mortality. The World Health Organization released an integrated strategy targeting HCV-elimination by 2030. This study aims to estimate the required interventions to achieve elimination using updated information for direct-acting antiviral(DAA) treatment coverage, to compute the total costs(including indirect/societal costs) of the strategy and to identify whether the elimination strategy is cost-effective/cost-saving in Greece.AIM To estimate the required interventions and subsequent costs to achieve HCV elimination in Greece.METHODS A previously validated mathematical model was adapted to the Greek HCVinfected population to compare the outcomes of DAA treatment without the additional implementation of awareness or screening campaigns versus an HCV elimination strategy, which includes a sufficient number of treated patients. We estimated the total costs(direct and indirect costs), the disability-adjusted life years and the incremental cost-effectiveness ratio using two different price scenarios.RESULTS Without the implementation of awareness or screening campaigns,approximately 20000 patients would be diagnosed and treated with DAAs by2030. This strategy would result in a 19.6% increase in HCV-related mortality in2030 compared to 2015. To achieve the elimination goal, 90000 patients need to be treated by 2030. Under the elimination scenario, viremic cases would decrease by78.8% in 2030 compared to 2015. The cumulative direct costs to eliminate the disease would range from 2.1-2.3 billion euros(€) by 2030, while the indirect costs would be €1.1 billion. The total elimination cost in Greece would range from €3.2-3.4 billion by 2030. The cost per averted disability-adjusted life year is estimated between €10100 and €13380, indicating that the elimination strategy is very costeffective. Furthermore, HCV elimination strategy would save €560-895 million by2035.CONCLUSION Without large screening programs, elimination of HCV cannot be achieved. The HCV elimination strategy is feasible and cost-saving despite the uncertainty of the future cost of DAAs in Greece.

商品房住宅区公共物业自治管理制度分析 以上海市水仙苑小区为例

The reform of the housing system in Shanghai has unexpectedly given rise to a self-governed property owners’ collective supervisory system, primarily in the form of Property Owners’ Supervisory Council (POSC), which has picked up some of the government’s administrative functions. Although this new, institutionalized management model has theoretically made democratic managerial participation at the grassroots level possible, it has brought about endless problems, overt and covert, shortly after its appearance, some of which are even alarming. A comprehensive analysis of the data collected over a long period of time has led to the conclusion that this system is a failure, attributable to the overt factor related to skills in reality and the covert “priori” factor that is masked by the former. The existence of such “priori” factor once again demonstrates the deep-rooted, traditional managerial logic: Positive operations is society need only to depend upon individuals’ unstable self-disciplined morality rather than to build a system. The current paper points out that any change in the socioeconomic structure that has long been subject to the power of politics is to inevitably incur a corresponding global structural accommodation, including politics itself. To respond to the two factors for the failure, system building in the two overlapping areas is a must.

Prevalence of metabolic syndrome in type 2 diabetic patients: A comparative study using WHO, NCEP ATP III, IDF and Harmonized definitions

To determine the prevalence of metabolic syndrome (MetS) in Malaysian type 2 diabetic patients using WHO, NCEP ATP III, IDF and the new Harmonized definitions, and the concordance between these definitions. This study involved 313 patients diagnosed with type 2 diabetes mellitus (T2DM) at two Malaysian tertiary hospitals. Socio-demographic data were assessed using a pre-tested interviewer-administered structured questionnaire. Anthropometric measurements were carried out according to standard protocols. Clinical and laboratory characteristics were examined. Kappa (k) statistics were used for the agreement between the four MetS definitions. The overall prevalence rates of MetS (95% CI) were 95.8% (93.6-98.1), 96.1% (94.0-98.3), 84.8% (80.8-88.9) and 97.7% (96.1-99.4) according to the WHO, NCEP ATP III, IDF and the Harmonized definitions, respectively. The Kappa statistics demonstrated a slight to substantial agreement between the definitions (k = 0.179-0.875, p k = 0.875, p hest specificity (100%) in identifying MetS. In conclusion, the new Harmonized criteria established the highest prevalence of MetS among the four definitions applied. There was a very good concordance between the WHO and NCEP ATP III criteria. The extremely high prevalence of MetS observed in type 2 diabetic patients indicates an impending pandemic of CVD risk in Malaysia. Aggressive treatment of MetS components is required to reduce cardiovascular risk in T2DM.

Heterogeneity in the regenerative abilities of central nervous system axons within species: why do some neurons regenerate better than others?

Some neurons,especially in mammalian peripheral nervous system or in lower vertebrate or in vertebrate central nervous system(CNS)regenerate after axotomy,while most mammalian CNS neurons fail to regenerate.There is an emerging consensus that neurons have different intrinsic regenerative capabilities,which theoretically could be manipulated therapeutically to improve regeneration.Population-based comparisons between"good regenerating"and"bad regenerating"neurons in the CNS and peripheral nervous system of most vertebrates yield results that are inconclusive or difficult to interpret.At least in part,this reflects the great diversity of cells in the mammalian CNS.Using mammalian nervous system imposes several methodical limitations.First,the small sizes and large numbers of neurons in the CNS make it very difficult to distinguish regenerating neurons from non-regenerating ones.Second,the lack of identifiable neurons makes it impossible to correlate biochemical changes in a neuron with axonal damage of the same neuron,and therefore,to dissect the molecular mechanisms of regeneration on the level of single neurons.This review will survey the reported responses to axon injury and the determinants of axon regeneration,emphasizing non-mammalian model organisms,which are often under-utilized,but in which the data are especially easy to interpret.

Formation,evolution,reconstruction of black shales and their influence on shale oil and gas resource

Black shales are important products of material cycling and energy exchange among the lithosphere,atmosphere,hydrosphere,and biosphere.They are widely distributed throughout geological history and provide essential energy and mineral resources for the development of human society.They also record the evolution process of the earth and improve the understanding of the earth.This review focuses on the diagenesis and formation mechanisms of black shales sedimentation,composition,evolution,and reconstruction,which have had a significant impact on the formation and enrichment of shale oil and gas.In terms of sedimentary environment,black shales can be classified into three types:Marine,terrestrial,and marine-terrestrial transitional facies.The formation processes include mechanisms such as eolian input,hypopycnal flow,gravity-driven and offshore bottom currents.From a geological perspective,the formation of black shales is often closely related to global or regional major geological events.The enrichment of organic matter is generally the result of the interaction and coupling of several factors such as primary productivity,water redox condition,and sedimentation rate.In terms of evolution,black shales have undergone diagenetic evolution of inorganic minerals,thermal evolution of organic matter and hydrocarbon generation,interactions between organic matter and inorganic minerals,and pore evolution.In terms of reconstruction,the effects of fold deformation,uplift and erosion,and fracturing have changed the stress state of black shale reservoirs,thereby having a significant impact on the pore structure.Fluid activity promotes the formation of veins,and have changed the material composition,stress structure,and reservoir properties of black shales.Regarding resource effects,the deposition of black shales is fundamental for shale oil and gas resources,the evolution of black shales promotes the shale oil and gas formation and storage,and the reconstruction of black shales would have caused the heterogeneous distribution of oil and gas in shales.Exploring the formation mechanisms and interactions of black shales at different scales is a key to in-depth research on shale formation and evolution,as well as the key to revealing the mechanism controlling shale oil and gas accumulation.The present records can reveal how these processes worked in geological history,and improve our understanding of the coupling mechanisms among regional geological events,black shales evolution,and shale oil and gas formation and enrichment.