Assessing the Impact of Gold Mining on the Quality of Water Resources in the Commune of Meguet, Burkina Faso

Despite its often illegal nature, artisanal gold mining in Burkina Faso contributes to the economic and social development of the country. However, the rudimentary techniques used in gold panning have a significant impact on the environment due to inappropriate practices and the use of various chemical substances. This study aims to assess the impact of artisanal gold mining on the quality of water resources in a rural community at Méguet, Burkina Faso. To this end, surface and groundwater samples were collected and analyzed at the BUMIGEB laboratory. Field results show that the waters are slightly alkaline (6.97 < pH < 8.1), weakly mineralized and conductive (124 < EC < 543 μS/cm), with temperatures ranging from 24.6˚C to 31.6˚C. In addition, trace metals (TMEs) analyzed from surface and subsurface waters show very high levels, generally deviating from the levels recommended by WHO guidelines for Burkina Faso. Trace metals contamination of water resources in the commune of Méguet is mainly due to Fe (3.78 - 11.12 mg/kg), Hg (0.03 - 0.29 mg/kg), As (0.01- 6.31 mg/kg) and Pb (0.01 - 3.8 mg/kg). This study can serve as a basis for guiding national environmental policies to protect the water resources of the Méguet mine.

Comparative Study of the Physicochemical Quality of the Waters of the Méné River (Sassandra Watershed, Ivory Coast) in the Dry Season and in the Rainy Season

The study carried out on the waters of the Méné River led to an overall assessment of its water quality during the dry season and the rainy season. The analysis focused on eight (8) water samples taken from the river during a period of dry season (January-February) and a period of rainy season (June and September). The various physicochemical parameters were measured according to Afnor standardized methods. The readings of temperature, turbidity, pH and conductivity made it possible to account for the disturbances occurring in water quality. A temporal variation correlated with the seasons (dry or rainy) is noted. Turbidity depends on the concentration of suspended solids (SS) in the water and drained particles and therefore on the seasons. Just like the temperature, the conductivity changes with the season. The waters of the Méné River are generally acidic. The results obtained show that there is a low level of pollution by chlorides, phosphates, nitrites and nitrates. A slight pollution of the waters of Méné in organic matter (chemical oxygen demand values are less than 25 mg∙L−1 during dry season and 32.33 ± 4.73 mg∙L−1 during rainy season) was observed. The concentrations of metallic trace elements such as iron, manganese and aluminum indicate significant pollution of these waters by these elements. Overall, the waters of the Méné River are of satisfactory quality because all the physicochemical parameters analyzed have values below standards during the dry season as well as during the rainy season with the exception of COD and a few metallic trace elements.

Assessment of Groundwater Physico-Chemical Quality in the Ouémé Delta (Southern-Benin)

Groundwater resources are the main sources of water used to supply drinking water to the population of the Ouémé Delta via the Continental Terminal aquifer. Urbanization, population growth, and agricultural and industrial activities have resulted in a deterioration in the quality of these resources. To assess the quality of the delta’s groundwater and its suitability for human consumption and irrigation, a total of fourteen (14) physico-chemical parameters were analyzed in some forty existing water points between September 2020 and March 2021, using standard water analysis techniques. The values obtained were compared with the potability standards recommended by the World Health Organization (WHO) and the Republic of Benin and were subjected to statistical analysis (principal component analysis (PCA)). In addition, methods for determining the suitability of water for irrigation were used. The results showed that the waters are acidic to slightly neutral and influenced by ambient temperature. In addition, the waters are moderately mineralized, with conductivities (24 - 1205 μS/cm) in line with WHO standards. A comparison of the analytical results of the WHO (2017) and Benin (2001) standards indicates that the majority of the waters studied are of good quality for all the chemical parameters considered. Nevertheless, some samples show levels of nitrates (21%), potassium (14% to 16%), calcium (13%), ammonium (12%), nitrites (8%) and bicarbonates (10%) over their respective standards. The Wilcox and Riverside diagrams indicate that the majority of waters (90%) have excellent suitability for irrigation and no negative effect on soil fertilization.

Assessing Disclosure Quality： A Methodological Issue

The voluntary disclosure studies conducted until today, in social accounting and related fields, use different approaches to evaluate the so-called ＂disclosure quality＂. Disclosure quality is not so easy to measure, and it is derived from the application of different methodologies. In particular, the methodologies to assess the level of disclosure could be classified as subjective or objective. To the first category belong all the ＂tools＂ that are used directly without relying on the analysis of the original source of the information studies （Imhoff, 1992; Coleman ＆ Eccles, 1997; Welker, 1995）. The objective measurements used to assess the disclosure quality are, instead, based on the direct study of the original information source in order to obtain the information required （Krippendorff, 1980; Weber, 1985; Botosan, 1997; Lang ＆ Lundholm, 2000）. The aim of the paper is to give scholars and researchers a brief framework to understand the different methodologies used in accounting literature to assess the disclosure quality, providing examples of the application of the same in different research contexts.

Evaluation and analysis of influencing factors on the quality of carbon disclosure:An empirical study of CDP in China

The purpose of this paper is to evaluate the quality of corporate carbon disclosure and to analyze its influencing factors. With the hand-collected carbon information from annual reports, social responsibility reports, sustainability reports and opened CDP questionnaires of the sample of 100 Chinese companies investigated by CDP from 2008-2011, the quality of carbon disclosure is defined by evaluating indicators obtained from factor analysis, and its influencing factors are studied from three aspects including company characteristics, financial features and corporate governance by means of correlation, differences comparison and regression analyses. Findings show that the quality of Chinese companies' carbon disclosure is mainly affected by company characteristics(such as the emission characteristics of one's industry and dual listed) and corporate governance(such as ownership concentration), but in perspective of financial features, there seems to be little relation between the disclosure quality and financing motivations. The practical implication of the paper is to help Chinese companies find out effective ways to improve carbon disclosure quality. The paper contributes to carbon disclosure literature by explaining the connotation of carbon information, providing a set of evaluation indicators of carbon disclosure and exploring the influencing factors from various perspectives.

The Effect of the Board of Directors and Audit Quality on Disclosure of Internal Control Practices: Evidence from European Companies

The purpose of this paper is to examine the effect of the board of directors,namely board size,board independence,and CEO duality,as well as audit quality on the disclosure of internal control information.The sample consists of 164 European companies listed in the STOXX Europe 600.Based on positive agency theory,the authors posit that board of directors and audit quality influence corporate internal control disclosure practice.The content analysis and the design of the evaluation criterion were used to calculate the disclosure index of internal control.Thus,multiple regression analysis is utilized to analyze the results of this paper.The average internal control information disclosure index was 0.285,indicating that most of the companies in our sample do not disclose enough information about the internal control.This low level of forward-looking information disclosure makes it very difficult for corporate stakeholders to determine the future performance of the company.Multivariate results indicate that internal control disclosure is positively and significantly associated with board independence,CEO duality,and audit quality.This study contributes to the literature on the various governance characteristics and disclosure by showing that the disclosure of internal control information in European countries is positively and significantly associated with board independence,separation of duties,and audit quality.Our study was based on a sample of European companies including countries regulating IC disclosure as well as unregulated settings.As noted by Bedard and Graham(2014),regulatory differences in countries can contribute insights on the costs and benefits of disclosure.Findings also have policy implications for investors,managers,and regulators.

Disclosure Quality in Goodwill Impairment Tests： Turkey Case

The issue of goodwill impairment has been debated in many countries throughout the world. Adoption of International Financial Reporting Standards （IFRS） introduced fundamental changes in accounting and impairment methods for goodwill. Since global stock markets went into decline in 2008, there has been much debate over the issue of goodwill impairment in the US and European stock exchange markets, especially on how large the write-downs should be. Complexity of International Accounting Standards （IAS） and IFRS focusing on goodwill and goodwill impairment techniques may lead to inconsistent compliance and varying levels of disclosure quality. The aim of this study is to analyze goodwill impairment during and after the recent financial crisis for companies listed on the Borsa Istanbul （BIST） 100 index and to assist the financial statement users in the assessment of disclosure quality under IAS 36, Paragraph 134d. Tools such as： （1） the period over which management has projected cash flows; （2） the growth rate used for cash flow projections; （3） the discount rate（s） applied to projections; and （4） methods employed to determine recoverable amount are analyzed. Insufficient disclosures on these tools are observed. The findings are of interest to researchers examining the implication of IAS 36, regulators, and policy-setters.

The Effect of Social Responsibility Report Audit on the Quality of CSR Information Disclosure --Empirical Data from Chinese Listed Companies

As an important corporate govemance mechanism, external audit helps to improve corporate economic performance. Social responsibility report audit can supervise and constrain the disclosure of corporate social responsibility information, risk assessment and consulting planning, and improve the quality of information disclosure. Taking 2010-2013 listed companies in Shanghai and Shenzhen as samples for empirical test, we found that social responsibility report audit significantly improved the quality of corporate social responsibility information disclosure. Further study found that the greater the intensity of corporate shareholder oversight, social responsibility report audit on the quality of social responsibility to promote the quality of information disclosure more obvious. In addition, compared with the state-owned enterprises, the supervision of the major shareholders in the private enterprises to a greater extent enhanced the quality of social responsibility information disclosure.

New European Union＇s Requirements and IFRS Practice Statement ＂Management Commentary＂： Does MD＆A Disclosure Quality Affect Analysts＇ Forecasts？

The Management Discussion and Analysis （MD＆A） is a mandatory document under the European Union＇s （EU） law. In 2003, the EU issued Directive 2003/51/EC, which broadened the information that firms have to provide in their MD＆A, and in 2010 the International Accounting Standards Board （IASB） issued the International Financial Reporting Standards （IFRS） Practice Statement ＂Management Commentary＂, a non-binding guidance for the presentation of this document. The aim of this paper is to examine the relationship between MD＆A disclosure quality and properties of analysts＇ forecasts. In fact, although most studies found that financial analysts mainly refer to financial statement data in forecasting earnings, there are few researches highlighting the importance of MD＆A disclosures for financial analysts. On this basis, Ramnath, Rock, and Shane （2008） called for researches in order to better understand the relationship between the information really used by analysts and their forecasts. To assess the quality of MD＆A disclosures, we developed a multidimensional measure on the basis of the EU requirements and the IFRS Practice Statement, and then we regressed this variable on both forecast accuracy and dispersion. The findings show that our measure of MD＆A disclosure quality is significantly and positively related to forecast accuracy. We conducted other analyses in order to better understand the previous relationship and we found that, if we analyze the different information contained in the MD＆A statement, financial analysts consider useful accounting and financial data in forecasting earnings. These results enhance our understanding of the role of MD＆A disclosures in the wide set of information that firms provide to financial statement users.

M鲜生冰箱对冷藏鸡胸肉品质的影响

为实现M鲜生冰箱精准分区保鲜的目的,以普通冰箱4℃冷藏为对照,对比分析M鲜生冰箱及其不同层(由下至上分别为S1、S2、S3、S4,其与冰箱内电场保鲜电板的距离分别为5、40、65、75 cm,温度均为4℃)对鸡胸肉冷藏期间(1~7 d)菌落总数、总挥发性盐基氮、pH、贮藏损失率、蒸煮损失率、L^(*)值、a^(*)值、b^(*)值、剪切力、水分分布的影响。结果表明:普通冰箱冷藏3 d后的菌落总数、总挥发性盐基氮分别超过6(lg(CFU/g))和25 mg/100 g,说明其保质期仅为3 d;而M鲜生冰箱S2处理则可延长鸡胸肉保质期至5 d;在有效冷藏期内,M鲜生冰箱S2组的贮藏损失率、蒸煮损失率、剪切力值、b^(*)值、自由水相对比例最低,L^(*)值、a^(*)值、不易流动水相对比例最高,说明M鲜生冰箱S2处理能有效减少鸡胸肉的汁液流失,维持肉样的保水性,延缓其色泽劣变,护色效果最佳,同时其也能较好地维持肉样的嫩度,提升鸡胸肉冷藏期间的整体品质。研究结果为M鲜生冰箱在肉类冷藏过程中分区的合理选择及应用提供了参考依据。

Quality disclosure strategies for small business enterprises under consumer loss aversion

In this paper,we focus on small business enterprises(SBEs)that usually have low market power but can rely on retailers to transact sales and gain the ability to disclose quality information.Moreover,consumer loss aversion(CLA)is pronounced when buying from SBEs that have yet to develop a strong reputation and uncertain quality.We focus on two competing SBEs with heterogeneous quality levels and discuss their quality disclosure strategiesd whether selling through a retailerd in the context of CLA.We study the interaction between consumers'prior belief in product quality and CLA and how these factors affect equilibrium outcomes.We show that a situation in which low-quality and high-quality SBEs both choose to disclose will not occur under a neutral consumer attitude,i.e.,it happens only when the aversion level is significant.When the aversion level is low,either the low-quality SBE or the high-quality SBE will decide to disclose,and the disclosing party depends on the prior belief.In addition,CLA significantly impacts the monotonicity of both SBEs'and retailers'prices and profits relating to the consumers'prior beliefs.

基于VMD-DBO-LSTM的空气质量预测

针对传统空气质量预测模型收敛速度慢,精度低的问题,提出一种基于变分模态分解(variational mode decomposition,VMD)和蜣螂优化算法(dung beetle optimizer,DBO)优化长短期记忆网络(long short term memory,LSTM)的预测模型。首先,针对AQI原始数据具有大量噪声的问题,使用VMD方法对非平稳信号进行模态分解以降低噪声对预测结果的影响从而获得多个不同特征的模态分量;其次,针对LSTM靠人工经验调参存在一定局限性,利用DBO算法对LSTM模型参数进行优化;最后,对分解后的各个子序列使用LSTM模型预测,将各个子序列进行叠加得到最后的预测结果。实验结果表明,VMD对非平稳数据的分解有助于提高预测精度,VMD-DBO-LSTM模型的性能较其他模型均有不同程度的提高,该模型预测的均方根误差为4.73μg/m^(3),平均绝对误差为3.61μg/m^(3),拟合度达到了97.8%。

The Moderating Role of Ownership Structure on the Relation between Board Independence and Voluntary Financial Disclosure: An Analysis of Italian Listed Company

Voluntary disclosure and corporate governance variables, such as board independence and ownership structure are considered mechanisms useful to reduce information asymmetries between competing parties of the firms. This paper aims at investigating both the relationship between board independence and the quality of voluntary financial disclosure and how previous relationship is moderated by the level of ownership concentration. The analysis has been conducted on a sample of Italian non-financial listed companies. The results show that there is a positive and significant relationship between board independence and the quality of voluntary financial disclosure provided by companies. In addition, the findings reveal that ownership concentration plays a relevant moderating role in previous relationship. The results highlight the necessity to consider the interaction effects of different governance mechanisms, when studying corporate governance effectiveness.

红透山铜锌矿-877 m采场稳定性分析试验研究

通过矿岩力学强度测试和工程地质调查对红透山铜锌矿-877 m试验采场稳定性开展研究,重点分析矿岩质量评价结果和采场顶板水力半径计算结果。研究结果表明:RMR法和Q法对矿岩质量评价均为好;通过Mathews稳定图法计算得出矿石稳定区的临界水力半径为6.9 m;当单个采区顶板矿石跨度不超过15 m时,矿石水力半径小于6.9 m;当盘区顶板矿石跨度不超过14 m时,矿石水力半径小于6.9 m,此时采场处于稳定状态,不需支护。

Analysis of Change in Sperm Quality of Chinese FertileMen druing 1981～1996

By literature search, 114 papers for fertile m ale sperm quality including 256 set data w ere collected from 9 292 personsand 11 726 assaysinvolving 39 citiesand coun- ties. Results of analysis show ed a decrease in m ean concentration of sperm from 103.02×106 /m l (1983) to 83.84×106/m l (1996), sperm m otility w as decreased from 75.11(1982) to 67.27(1996) and percentage of sperm w ith norm alm or- phology w asreduced from 85.02(1983) to 77.89(1996), thusshow ing thedefi- nite negative correlation and being statistically significant (P< 0.05). Total sperm countsw ere decreased from 355.34×106(1984) to 262.26×106(1996) and the m ean sem inalvolum ew asdecreased from 3.31 m l(1981) to 2.97 m l(1996), both tending to decline butnotbeing statistically significant(P> 0.05). Itisinteresting to notethat although Chinese sperm quality is better, itdeclines significantly faster than thatof w estern countriesatthesam eperiod. Itispossible thatthe decline of sperm quality is due to problem of environm entalquality. Theauthorssuggesttheemphasisof basicre- search in relevantfields.

Assessing the benthic habitat quality in the Huanghe(Yellow River) Estuary and its adjacent areas using AMBI and M-AMBI

The protection of the biological diversity and the maintenance of the regional ecological integrity for the Huanghe （Yellow River） Estuary and its adjacent areas are practically significant and valuable. However, frequent human activities and natural climate changes have caused vigorous disturbances on the ecosystem in these sea areas. An objective assessment on the benthic habitat quality （BHQ） of the Huanghe Estuary and its adjacent areas is conducted, using AZTI＇s Marine Biotic Index （AMBI） and multivariate AMBI （M-AMBI） based on the data of macrobenthos in May and August 2011. The results show that both the indices do not correlate significantly, and their assessment results are greatly different. All of the samples assessed using the AMBI were ＂high＂ or ＂good＂, because the ecological group I （EGI） and the ecological group II （EGII） were dominant macrobenthic ecological groups in the research area. Owing to a low species＇ richness and a high individual abundance in some samples, the BHQ levels using the M-AMBI were worse than those of the AMBI. Significant correlations are observed between the M-AMBI, water depth, bottom water salinity and dissolved inorganic nitrogen, thus the M-AMBI could sensitively respond to environmental changes and distinguish influences from uninfluenced stations, but the AMBI could not. The consistent results between the AMBI and the M-AMBI mainly appeared in the uninfluenced （undisturbed or slightly disturbed） sta- tions. Therefore, the M-AMBI is more effective than the AMBI in assessing the benthic habitat quality in the Huanghe Estuary and its adjacent areas. Using the M-AMBI to assess the BHQ of the Huanghe Estuary and its adjacent areas, the results show that 3% of the stations are undisturbed and the BHQs are ＂high＂, and 61% of the stations are slightly disturbed and those of the BHQ are ＂good＂, and the rest are meanly disturbed and those of the BHQ are ＂moderate＂.

Techniques trend analysis of propagating laser beam quality measurement

Different methods of measuring a propagating laser beam quality are summarized.The disadvantages in traditional way in measuring a laser beam quality is analyzed and the insufficiencies of the Shack-Hartmannin method which is commonly using wave front technique at present is pointed out.Finally,the transmission intensity equation based(TIE-based)measuring way in a laser beam quality evaluation and the corresponding advantages are discussed,which is believed to be a deve-l oping trend in laser beam evaluation.

A multidimensional and hierarchical model of library mobile service quality

Purpose:Based on the understanding of the characteristics of mobile services(m-services)provided by libraries,we attempt to develop a multidimensional and hierarchical model and a specifically designed measurement scale for the assessment of libraries' m-service quality.Design/methodology/approach:The research has been conducted sequentially in two stages.At the first stage,a multidimensional and hierarchical model of library m-service quality and a measurement scale are developed through literature review and focus group interviews.At the second stage the model is tested using partial disaggregation technique for an analysis of the data collected from over 400 library users in 3 Chinese universities.Findings:The proposed model is shown to fit the data well.The empirical analysis provides strong support for the model,which includes 4 dimensions(service environment,service interaction,information control and service effect) and 12 corresponding sub-dimensions.Research limitations:The sample size needs to be enlarged and the user types need to be expanded to make the sample more representative.Practical implications:The study provides a conceptual framework and measurement tool that can help library managers understand the users' needs in the context of mobile network environment,and boost their libraries' competitiveness by carrying out better services to meet the user demands.Originality/value:The proposed model and measurement scale specifically designed for the assessment of libraries' m-service quality fully reflect the hierarchical structure of libraries' m-service quality.In addition,by using partial disaggregation technique for model testing,we believe our research can serve as a practical reference to those engaged in the development and examination of a multidimensional and hierarchical model.

企业数字化转型对客户集中度的影响

企业数字化转型是中国发展数字经济中的重要一环,在很大程度上推动了数字经济与实体经济实现融合发展,进而使中国在新一轮国际竞争中获得重要优势。采用2011—2021年沪深两市A股上市公司的数据,对数字化转型和客户集中度的关系及其中的渠道机制进行实证检验。研究结果表明,随着企业数字化转型程度的提升,客户集中度会显著降低,在这一过程中,数字化转型会提高企业进行高质量信息披露的能力和动力,从而缓解过于集中的客户资源给企业带来的压力。此外,对于销售费用率和盈余管理程度较高、全要素生产率和分析师关注度较低的企业以及非国有企业来说,进行数字化转型能够更加显著地为企业吸引客源,减少客户集中度。同时,相对于数字经济发展还较为落后的省份,处于数字经济发展水平较高地区的企业,更有可能通过进行数字化转型显著降低对大客户的依赖程度。最后,研究发现数字化转型降低客户集中度后,可以进一步提高企业市场地位。

董事高管责任保险与碳信息披露质量

在实现国家“碳达峰、碳中和”战略目标的背景下,上市公司紧跟国家政策导向,积极履行自愿披露碳信息的义务。基于此,本文以2015~2022年中国A股上市公司为样本,实证检验了董责险对碳信息披露质量的影响。研究发现,董责险通过最大诚信原则的保险文化、保险公司的持续监督和自发传递积极的信号,提高企业的碳信息披露质量。机制上,董责险提高内部控制质量,进而影响碳信息披露质量。进一步地,当上市公司属于重点排污单位、处于非低碳试点城市、市场化程度高时,董责险对碳信息披露质量的影响更显著。本文研究为构建更完善的保险服务体系、深化绿色低碳转型的治理体系提供了理论依据,并对我国实现“双碳”战略目标具有一定的启示意义。