ANALISIS KANDUNGAN MIKROPLASTIK PADA USUS IKAN TUNA MATA BESAR (Thunnus obesus) YANG DIDARATKAN DI PELABUHAN IKAN WAKATOBI

Pencemaran plastik memiliki efek terhadap perairan laut dan terbatasnya informasi mengenai dampak terhadap saluran pencernaan ikan migrasi. Oleh karena itu, penelitian ini bertujuan untuk menganalisis kandungan mikroplastik pada sistem pencernaan ikan yang terletak pada bagian usus dan identifikasi jenis polimer mikroplastik pada daging ikan tuna mata besar yang didaratkan di pelabuhan ikan Wakatobi. Penelitian ini dilaksanakan pada bulan Maret sampai Juli 2020 di Kabupaten Wakatobi. Proses identifikasi kandungan mikroplastik pada usus ikan tuna mata besar dilakukan dengan 4 tahap, yaitu (1) tahap pembedahan ikan, (2) pemisahan densitas, (3) penghilangan senyawa organik, (4) pengamatan visual. Identifikasi jenis polimer mikroplastik pada daging ikan tuna mata besar dianalisis menggunakan fourrier trasform infrared (FTIR). Hasil penelitian menunjukkan bahwa terdapat mikroplastik pada usus ikan tuna mata besar berjumlah dua belas partikel dengan tipe mikroplastik berupa fiber berwarna biru, cokelat dan merah. Ukuran mikroplastik yang ditemukan yaitu 0,701-4,305 mm. Hasil analisis FTIR pada daging ikan menunjukkan senyawa polyethylene ditandai dengan adanya ikatan C=O stretch.Plastic pollution has an effect on marine waters and limited information about the impact on the digestive tracts of migratory fish. Therefore, this study aims to analyze the content of microplastics in the digestive system of fish that are located in the intestines and identify the type of microplastic polymers in the meat of big-eyes tuna fish landed in the port of Wakatobi fish. The research was conducted from March to July 2020 in Wakatobi Regency. The process of identifying the microplastic content in the intestines of bigeyes tuna was carried out in 4 stage, namely (1) fish disscetion, (2) density separation, (3) removal of organic compounds, (4) visual observation. Identification of the type of microplastic polymers in meat of bigeyes tuna was analyzed using fourier transform infrared (FTIR). The results showed that there are microplastics in the intestines of big-eyes tuna fish numbering twelve particles with microplastic types in the form of blue, brown and red fibers. The size of microplastic which found was 0.701-4.305 mm. The results of FTIR analysis on fish meat showed polyethylene compounds marked by the presence of C=O stretch bonds

Critical and Contextual Perspectives on International Economic Law: Amplifying the Voices of African Students and Early-Career Researchers

In African universities, the teaching and scholarship of international economic law (IEL) are dominated by Eurocentric epistemological and methodological frames (al Attar, 2020; Zongwe, 2022; Oyakhire, 2020). Too often, IEL and the broader international law discipline are taught within Africa’s westernised ‘Ivory Towers’ in a manner that fails to interrogate how IEL is both constituted by and constitutive of global inequality and imperialism. This a-historical and a-contextual framing of the IEL discipline presents unequal global economic relations as universal and fixed there by sheltering the discipline of international law from the creative, disruptive energy of young international law scholars (al Attar, 2020). In response to the challenges identified above, the Afronomicslaw Academic Forum was set up in May 2020 as a platform for convening African students, early-career researchers and early-career practitioners to debate and learn about IEL from a critical perspective – an opportunity that some of our members have not been exposed to in their respective universities. The Forum provides an opportunity for its members to self-organise in an alternate space. Our members have studied at over 50 African universities, giving us great insight into the gaps in formal IEL education on the continent and making clear the need for a flexible, informal space to explore gaps and opportunities in international economic law teaching, scholarship and practice in Africa. The Academic Forum is run by its members who engage in this transformative and liberating process of learning about IEL by working 'with' and 'in solidarity with' each other (Rodino-Colocino, 2011, p. 1702; al Attar and Tava, 2010). We challenge ourselves to examine power structures and patterns of inequality within the IEL status quo. Utilising a mix of critical guest lectures, spontaneous conversations on topical issues relating to IEL in Africa, virtual debates, practical skills workshops, informal mentorship and peer-evaluation of writing, the Academic Forum is shaping the agenda and debates on decolonising IEL teaching and scholarship in Africa and beyond. In response to some of the critical gaps we have identified in the teaching and scholarship of IEL in Africa, the Academic Forum planned a writing symposium and conference on the topic of "Critical and Contextual Perspectives on International Economic Law: Amplifying the Voices of African Students and Early-Career Researchers". After the call for papers was released, participating Regional Representatives were provided with ongoing, personalised editorial support from Regional Editors to produce a publication-ready submission. The symposium culminated in a conference held virtually on 5 February 2022. The conference had 300 registered participants worldwide, with an average of 100 attendees on the day of the event. The conference allowed our members to present the critical work they produced in the months leading up to the conference. It encouraged conversation between experienced IEL scholars (who attended the conference as Panel Chairs and as guests) and our emerging researchers. Over the next few weeks, we will publish papers from the conference which cover several thematic areas of importance to Africa in the IEL discourse. The contributions from the conference presented in this symposium offer diverse perspectives of our Academic Representatives on important topics such as the African Continental Free Trade Agreement (AfCFTA), Africa's flagship free trade agreement which has dominated the headlines in recent years. The contributions from Wayne Rukero, Khalil Badbess, and Kathleen Mpofu focus on the AfCFTA Investment Protocol Negotiations. Rukero explores how regional and international law principles are implemented alongside and through the use of domestic legal instruments. Focusing on Namibia as a case study, Rukero's paper probes whether the investment law arrangements in Namibia illuminate an unsustainable investment regime aimed at reclaiming sovereignty and isolationist guises despite a growing need for African regional investment law and policy harmonisation. Badbess's paper, which is a critical review of the article by Ndanga Kamau in the African Journal of International Economic Law, explores arguments by Kamau about the fragmentation of international investment law (IIL) reforms in Africa and its implication for claims to the 'Africanisation' of International Investment Law (Mbengue, Schacherer and Akinkugbe). Mpofu explores the opportunities and challenges for embedding sustainable development goals under the Investment Protocol of the AfCFTA. Closely related to the discussions on the link between sustainable development and Investment Law, Vianney Sebayiga's paper critiques the Ugandan Model Bilateral Investment Treaty (BIT) and its lack of provisions for the conservation of the environment. The contributions from Sharon Nyaga and Yankho Mwandidya explore the theme of gender within IEL discourse. Focusing on Kenya as a case study, Nyaga critically appraises two assumptions connected with the relationship between foreign direct investment (FDI) and gender (in)equality. The first is that FDI contributes to gender equality; the second is that FDI may indeed be the shackle to gender equality. Mwandidya’s contribution focuses on the status of women in regional integration processes in Africa. It concludes by providing recommendations for the inclusion of women in the decision-making processes to facilitate regional integration in Africa. The contributions from Sumaya Nur and Dominee Ndlovu focus on the relationship between domestic tax policies and the AfCFTA and tax justice in Africa, respectively. Ndlovu explores the readiness of the AfCFTA Member States to optimise their tax policies and institutions to harness the anticipated revenue gains from the AfCFTA. Nur's paper reviews Fernando Saldivar's article published in the African Journal of International Economic Law. Nur critically appraises a central argument by Saldivar about involving Catholic Social Teaching as an intellectual and moral ally in the fight for systemic reform in the global financial order. Reflecting upon Dr Taimoon Stewart’s recent work ‘Competition Regimes in the Caribbean Community and Sub-Saharan Africa: A Comparison’, Nciko wa Nciko and Sidney Tambasi argue that there is not only a ‘race’ angle but there is also a ‘class’ angle to any better understanding of competition law issues in both the Caribbean Community and Sub-Saharan Africa. The co-authored contribution by Sharlene Kapere and Ali Abdilatif is a review of Titi Adebola's article published in the African Journal of International Economic Law which maps Africa's complex intellectual property (IP) regimes. Reflecting on Adebola's arguments, Kapere and Abdilatif emphasise the importance of understanding the IP Protocol as an opportune moment for Africa to realise trade-related IP needs. They also explore the utility of situating the proposed IP Protocol through its possible normative contributions in the broader multilateral trade context. Shifting to another proposed and much discussed AfCFTA Protocol, the Protocol on E-Commerce, Megan Kathure makes a case for recognising privacy and its derivative, data protection, in the AfCFTA's E-Commerce Protocol and subsequent e-commerce-related agreements concluded by Africa's Regional Economic Communities (RECs) and states. Gerald Ndobya's contribution explores the importance of equivalence and harmonisation of SPS measures in the SPS Agreement to Africa. Ndobya argues that Annex 7 of the Agreement establishing the AfCFTA is a copy-and-paste of the WTO SPS Agreement, disregarding Africa's unique challenges and opportunities. Azmimah Jhetam's contribution focuses on the potential for the AfCFTA Competition Protocol to function as a model law for African jurisdictions where there is no, or only a poorly developed and enforced, competition regime. Given the differing levels of development between developing and the LDC Member States, Mpeo Matsipa's contribution explores the potential impact of implementing the AfCFTA in LDCs. Contributions by Rogers Andagalu, Mwendabai Lubinda, Olavi Nangolo, Sharon Raston and Ester Da Conceição António focus on institutional issues in African RECs. Using the EU as a model, Andagalu explores the utility of implementing a division of competencies within the East African Community (EAC). Focusing on the Southern African Development Community (SADC), Lubinda argues that Special Purpose Vehicles (SPVs) have the potential to unlock and optimise economic activities within the SADC. Nangolo's paper also focuses on the SADC. His paper appraises the new jurisdiction of the SADC Tribunal and the implications this has on the settlement of disputes within the SADC region. Nangolo's article also looks at the extent to which the removal of private access from the Tribunal's jurisdiction affects the settlement of trade disputes within SADC; the relevance of the new Tribunal within the framework of Annex VI of the SADC Protocol on Trade ("the Protocol on Trade"); and whether the new Tribunal is reconcilable with World Trade Organization's dispute settlement mechanism. Still focusing on the SADC, António's paper reflects on how current economic and environmental trends are impacting the trading capacity and overall economic performance of SADC countries. Raston focuses on the lack of political will and inadequate infrastructure as critical challenges that militate against SADC's implementation of the AfCFTA. Alexander Chibayo's paper discusses the plunder of financial resources in Malawi amidst the COVID-19 pandemic. The analysis also highlights pre-existing corruption problems in Malawi and their effects on the country's global and regional economic participation. In light of the issues of corruption experienced during the COVID-19 Pandemic, Chibayo argues that domestic systems are insufficient to root out corruption and highlights the role of international systems in addressing corruption. Reflecting upon Dr Taimoon Stewart’s recent work ‘Competition Regimes in the Caribbean Community and Sub-Saharan Africa: A Comparison’, Nciko wa Nciko and Sidney Tambasi argue that there is not only a ‘race’ angle but there is also a ‘class’ angle to any better understanding of competition law issues in in the Caribbean and Sub-Saharan Africa. We hope the papers in this symposium will contribute to the ongoing efforts worldwide to achieve epistemological and methodological diversity in the IEL discipline. As a new Forum, we aim to remain flexible, experimental and responsive to the changing landscape in IEL. We will like to take this opportunity to thank the academics who have supported the Academic Forum over the last two years. We hope we can continue to count on your support as we devise robust and practical ways to decolonise and pluralise IEL research, scholarship and practice as a counterpoint to the dominant Western-centric IEL imagination

Early-Time Energy Loss in a Strongly-Coupled SYM Plasma

We carry out an analytic study of the early-time motion of a quark in a strongly-coupled maximally-supersymmetric Yang-Mills plasma, using the AdS/CFT correspondence. Our approach extracts the first thermal effects as a small perturbation of the known quark dynamics in vacuum, using a double expansion that is valid for early times and for (moderately) ultrarelativistic quark velocities. The quark is found to lose energy at a rate that differs significantly from the previously derived stationary/late-time result: it scales like T^4 instead of T^2, and is associated with a friction coefficient that is not independent of the quark momentum. Under conditions representative of the quark-gluon plasma as obtained at RHIC, the early energy loss rate is a few times smaller than its late-time counterpart. Our analysis additionally leads to thermally-corrected expressions for the intrinsic energy and momentum of the quark, in which the previously discovered limiting velocity of the quark is found to appear naturally.Comment: 39 pages, no figures. v2: Minor corrections and clarifications. References added. Version to be published in JHE

Exoplanets and SETI

The discovery of exoplanets has both focused and expanded the search for extraterrestrial intelligence. The consideration of Earth as an exoplanet, the knowledge of the orbital parameters of individual exoplanets, and our new understanding of the prevalence of exoplanets throughout the galaxy have all altered the search strategies of communication SETI efforts, by inspiring new "Schelling points" (i.e. optimal search strategies for beacons). Future efforts to characterize individual planets photometrically and spectroscopically, with imaging and via transit, will also allow for searches for a variety of technosignatures on their surfaces, in their atmospheres, and in orbit around them. In the near-term, searches for new planetary systems might even turn up free-floating megastructures.Comment: 9 page invited review. v2 adds some references and v3 has other minor additions and modification

Thermal photons in QGP and non-ideal effects

We investigate the thermal photon production-rates using one dimensional boost-invariant second order relativistic hydrodynamics to find proper time evolution of the energy density and the temperature. The effect of bulk-viscosity and non-ideal equation of state are taken into account in a manner consistent with recent lattice QCD estimates. It is shown that the \textit{non-ideal} gas equation of state i.e $\epsilon-3\,P\,\neq 0$ behaviour of the expanding plasma, which is important near the phase-transition point, can significantly slow down the hydrodynamic expansion and thereby increase the photon production-rates. Inclusion of the bulk viscosity may also have similar effect on the hydrodynamic evolution. However the effect of bulk viscosity is shown to be significantly lower than the \textit{non-ideal} gas equation of state. We also analyze the interesting phenomenon of bulk viscosity induced cavitation making the hydrodynamical description invalid. We include the viscous corrections to the distribution functions while calculating the photon spectra. It is shown that ignoring the cavitation phenomenon can lead to erroneous estimation of the photon flux.Comment: 11 pages, 13 figures; accepted for publication in JHE

The antisaccade task as an index of sustained goal activation in working memory: modulation by nicotine

The antisaccade task provides a laboratory analogue of situations in which execution of the correct behavioural response requires the suppression of a more prepotent or habitual response. Errors (failures to inhibit a reflexive prosaccade towards a sudden onset target) are significantly increased in patients with damage to the dorsolateral prefrontal cortex and patients with schizophrenia. Recent models of antisaccade performance suggest that errors are more likely to occur when the intention to initiate an antisaccade is insufficiently activated within working memory. Nicotine has been shown to enhance specific working memory processes in healthy adults. MATERIALS AND METHODS: We explored the effect of nicotine on antisaccade performance in a large sample (N = 44) of young adult smokers. Minimally abstinent participants attended two test sessions and were asked to smoke one of their own cigarettes between baseline and retest during one session only. RESULTS AND CONCLUSION: Nicotine reduced antisaccade errors and correct antisaccade latencies if delivered before optimum performance levels are achieved, suggesting that nicotine supports the activation of intentions in working memory during task performance. The implications of this research for current theoretical accounts of antisaccade performance, and for interpreting the increased rate of antisaccade errors found in some psychiatric patient groups are discussed

Physics Opportunities of e+e- Linear Colliders

We describe the anticipated experimental program of an e+e- linear collider in the energy range 500 GeV -- 1.5 TeV. We begin with a description of current collider designs and the expected experimental environment. We then discuss precision studies of the W boson and top quark. Finally, we review the range of models proposed to explain the physics of electroweak symmetry breaking and show, for each case, the central role that the linear collider experiments will play in elucidating this physics. (to appear in Annual Reviews of Nuclear and Particle Science)Comment: 93 pages, latex + 23 figures; typos corrections + 1 reference adde

Electronic learning can facilitate student performance in undergraduate surgical education: a prospective observational study

BACKGROUND: Our institution recently introduced a novel internet accessible computer aided learning (iCAL) programme to complement existing surgical undergraduate teaching methods. On graduation of the first full cycle of undergraduate students to whom this resource was available we assessed the utility of this new teaching facility. METHOD: The computer programme prospectively records usage of the system on an individual user basis. We evaluated the utilisation of the web-based programme and its impact on class ranking changes from an entry-test evaluation to an exit examination in surgery. RESULTS: 74.4% of students were able to access iCAL from off-campus internet access. The majority of iCAL usage (64.6%) took place during working hours (08:00–18:00) with little usage on the weekend (21.1%). Working hours usage was positively associated with improvement in class rank (P = 0.025, n = 148) but out-of hours usage was not (P = 0.306). Usage during weekdays was associated with improved rank (P = 0.04), whereas weekend usage was not (P = 0.504). There were no significant differences in usage between genders (P = 0.3). Usage of the iCAL system was positively correlated with improvement in class rank from the entry to the exit examination (P = 0.046). Students with lower ranks on entry examination, were found to use the computer system more frequently (P = 0.01). CONCLUSION: Electronic learning complements traditional teaching methods in undergraduate surgical teaching. Its is more frequently used by students achieving lower class ranking with traditional teaching methods, and this usage is associated with improvements in class ranking