Isolation and identification of an isomeric sildenafil analogue as an adulterant in an instant coffee premix

The proliferation of adulterated health foods and beverages in the market demands a comprehensive analytical strategy to identify the adulterants, particularly those of isomeric phosphodiesterase 5 (PDE5) inhibitors. An instant coffee premix (ICP) purchased from an online retailer was flagged for suspected adulteration through PDE5 inhibition assay. The ICP was then analysed using suspected-target and non-targeted screenings of a liquid chromatography-quadrupole time-of-flight mass spectrometry. Based on these findings, a PDE5 inhibitor initially assigned as compound X was isolated from the ICP by employing a liquid chromatography-diode array detection before its structural elucidation with liquid chromatography-ultraviolet (LC-UV) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. The suspected-target screening matched the protonated molecule ([M + H]⁺) precursor ion of compound X at m/z 499.2310 with two suspected analytes that are structural isomers of one another. The fragmentation patterns of compound X were comparable to those analogues in the dithiocarbodenafil group through the non-targeted screening. These findings, complemented by the LC-UV and NMR spectroscopy data, together with the chromatographic separation of related structural isomers, conclude the identity of compound X. To our best knowledge, this is the first study to report the presence of 3,5-dimethylpiperazinyl-dithiodesmethylcarbodenafil in an ICP sample.

Key points

• The herbal-based male sexual performance products’ lucrative market has instigated their rampant adulteration, particularly with PDE5 inhibitors.
• The adulterated products may also contain analogues of the approved PDE5 inhibitors, which usually passed into the market undetected as they are not included in the routine targeted screening procedure.
• The present study detected, isolated, and identified an isomeric sildenafil analogue from an instant coffee premix sample using rapid qualitative assay and comprehensive analytical analysis.
• This paper highlighted the applicability of the established strategies for routine casework, particularly in a forensic drug testing laboratory.

     

To survive is all: How the authoritarian core tackles neighboring dictatorships

This article attempts to answer why autocrats of illiberal regional powers intervene in the politics of neighboring dictatorships and argues that the dictator always prioritizes his survival and thus intervenes if he perceives his survival to be under direct threat. The formal model proposes three factors that determine the level of perceived threat: demographic composition, structural similarity, and regime dynamic of autocratic countries. The authoritarian core must pay close attention to those neighboring autocratic countries that are suffering from regime change, are close to its own densely populated region, and have regime types or social structure similar to itself. Additionally, if hostile ethnic or religious groups are highly concentrated in some areas of the authoritarian core where it borders autocracies experiencing regime instability, the authoritarian core will be motivated to intervene in the domestic affairs of those neighboring countries. Using QCA and case studies, this article confirmed that whether an authoritarian core will take action against countries in geographical proximity depends on a combination of these three factors.     

职业技能提升与体面劳动实现程度的互动关系 —— 基于北京市 4540份问卷调查数据的结构方程模型分析

通过对来自北京市职工的 4540 份问卷调查数据的结构方程模型（SEM）分析，检验了职工职业 技能提升与体面劳动实现程度的互动关系。分析结果验证了质性研究提出的三条理论假设，即职业技能水平的 提高增进体面劳动各维度的实现程度，体面劳动各维度的实现程度提高促进企业与职工的职业技能提升投入， 职业技能提升投入的增加导致职工职业技能水平的提升。因而，职业技能提升与体面劳动的实现互促互进，并 且体面劳动实现对职业技能提升的促进作用超过其反向关系。实现职业技能提升与体面劳动实现的良性循环， 是当前我国构建和谐劳动关系，推进供给侧结构性改革，实现产业转型升级与增长方式转变的必由之路。     

国际关系理论与实践:研究邓小平外交思想的新视角

本文从几种国际关系主流理论对外交决策的要求出发,分析了邓小平外交决策和外交思想是如何适应国际关系发展规律的。传统现实主义、新现实主义、自由制度主义等理论提出了国际体系中影响国家对外政策中的不同关键因素,反映着国际关系的总体要求。邓小平外交思想就是这样一种理性的、符合中国国情和国际体系要求的思想结晶。     

The blind spots of liberal citizenship and integration policy

Governments across Europe have stepped up their efforts to manage social diversity politically, often specifically targeting Muslim populations. Lewicki interrogates the policy tools that the British and German governments deploy to ‘integrate’ an increasingly stigmatized and racialized population, zooming in on whether and how they problematize patterns of inequality. Complicating the ‘one country, one citizenship’ rationale of the citizenship regime literature that assumes a one-dimensional interpretation of history, cultural identity, political institutions or legal norms, she points to four salient liberal citizenship discourses that currently frame policies of diversity management. These are civic republicanism, multiculturalism, civic universalism and cosmopolitanism. Her analysis demonstrates that all four liberal citizenship discourses have blind spots when it comes to problematizing structural hierarchies and the logics of racism. Over the last two decades, liberal citizenship and integration policy frameworks have thus contributed to the retention of binary distinctions between superior citizens and inferior Others, distinctions that can now easily be exacerbated and used for mobilization by right-wing populist movements.     

Is global inequality getting better or worse? A critique of the World Bank’s convergence narrative

The dominant narrative of global income inequality is one of convergence. Recent high-profile publications by Branko Milanovic and the World Bank claim that the global Gini coefficient has declined since 1988, and that inter-country inequality has declined since 1960. But the convergence narrative relies on a misleading presentation of the data. It obscures the fact that convergence is driven mostly by China; it fails to acknowledge rising absolute inequality; and it ignores divergence between geopolitical regions. This paper suggests alternative measures that bring geopolitics back in by looking at the gap between the core and periphery of the world system. From this perspective, global inequality has tripled since 1960.     

Forests lost and found in tropical Latin America: the woodland ‘green revolution’

Forest dynamics in the Latin American tropics now take directions that no one would have predicted a decade ago. Deforestation in the Brazilian Amazon has dropped by over 80 percent, a pattern mimicked elsewhere in Amazonia, and is down by more than a third in Central America. Forest resurgence – increasing forest cover in inhabited landscapes or abandoned lands – is also expanding. In Latin America, woodland cover is increasing, at least for now, more than it is being lost. These dramatic shifts suggest quite profound and rapid transformations of agrarian worlds, and imply that previous models of understanding small-farmer dynamics merit significant review centering less on field agriculture and more on emergent forest regimes, and in many ways a new, increasingly globalized economic and policy landscape that emphasizes woodlands.

This paper analyzes changing deforestation drivers and the implications of forest recovery and wooded landscapes emerging through social pressure, social policy, new government agencies, governance, institutions, ideologies, markets, migration and ‘neo-liberalization’ of nature. These changes include an expanded, but still constrained, arena for new social movements and civil society. These point to significant structural changes, changes in tropical natures, and require reframing of the ‘peasant question’ and the functions of rurality in the twenty-first century in light of forest dynamics.     

“Orbiting the Core”: Politics and the Meaning of Dialect in Chinese Linguistics, 1927–1957

In 1956, the Chinese Communist state launched its official language policy, which included the promulgation of a standard spoken language, called Putonghua. Their justification for this policy and their methods for implementation were guided by intellectual and ideological frameworks that formed during decades preceding the policy's rollout. In particular, Communist language reform was predicated on the conceptualization of Putonghua as a holistic language meant to serve the national body—and of local dialects, called fangyan in Chinese, as dependent on Putonghua for their very definition. This article interrogates the history of this framework. Focusing on dialect surveys from the 1930s, Chinese interpretations of Marxist linguistic theory in the early years of the Communist state, and methods of Putonghua promulgation in the late 1950s, this article reconstructs the epistemological regimes that gave meaning to the concept of independence and autonomy as they related to language in modern China.     

人的发展与人的尊严:再思人的安全概念

“人的安全”概念的提出促使人们对安全内涵和如何提供安全进行更深刻的思考。但是,人的安全概念提出后引发了很多争议,也产生了不少误区,其中之一就是将人的安全中“免于恐惧的自由”与“免于匮乏的自由”相互对立起来,以至于将前者视为西方的概念而后者为东方的概念。在这种话语中隐含了“免于恐惧的自由才是人的安全中优先考虑的因素”,其产生的后果是在全球范围内存在的贫困、饥饿等严重危害人的尊严的安全问题可能被置于安全考虑范围之外。回顾人的安全概念之争,探讨人的安全的核心理念及其相关概念,比如安全与发展、直接暴力与结构暴力之间的关系,可以矫正这种误区,并证明人的安全概念既不是西方的也不是东方的,它是以人类最基本的价值、需求和尊严为中心的,具有普遍意义的和道德说服力的综合性理念。这种综合性界定自然要求安全维护的方式不应停留在被动和短期应对层面而应寻求早期预防、长期建构、能力提升等积极手段以便实现“积极安全”。     

Citizen and Open Government: An Empirical Analysis of Antecedents of Open Government Data

Given the lack of empirical research investigating citizens’ use of open government, this study examines the antecedents of citizens’ use of open government data. Based on technology acceptance and motivation theory, this article proposes and empirically tests a research model, applying structural equation modeling to survey data collected from 210 citizens. The findings show that ease of use, usefulness, intrinsic motivation, and Internet competence significantly determine citizens’ intention to use open government data. Overall, this study contributes to the understanding of citizens’ attitudes and behavior in the context of open government and offers implications for research and practice.