Aquaporin-4-IgG Positive Neuromyelitis Optica Spectrum Disorder from Ethiopia: A Case Report

BACKGROUND: Neuromyelitis Optica spectrum disorder is an inflammatory disorder affecting the central nervous system), most commonly attacking the spinal cord or optic nerves. Limited cases of neuromyelitis optica have been reported in east Africa. Based on my review, if published, this would be the second published case of Neuromyelitis Optica spectrum disorder and the first published case of seropositive Neuromyelitis Optica spectrum disorder reported from Ethiopia. It signifies the need to have a high index of suspicion to promptly identify and properly treat these patients.CASE PRESENTATION: I am reporting a 32 years old female patient from Addis Ababa, Ethiopia, who presented with recurrent lower limb weakness and impairment of right eye vision of two-year duration. She was diagnosed based on Neuromyelitis Optica spectrum disorder diagnostic criteria, by having transverse myelitis, optic neuritis, confirmed by MRI imaging and high level of aquaporin-4-antibodies. Symptoms improved after providing five days of Methylprednisolone followed by low doses of corticosteroids and Azathioprine. The patient is now fully functional except for the right eye vision impairment.CONCLUSION: The patient described here signifies a classic manifestation of Neuromylitis Optica disorder with aquaporin- 4-IgG occurring in Ethiopian woman. This case highlights the existence of Devic’s disease within our setting and the need toproperly diagnose this condition even in a resource-limited setting to avert disability

Predictive validity of NLP-based ESG controversy scores

ESG-kontroversvurderinger basert på naturlig språkbehandling (NLP) av medieomtale, ticker-meldinger og selskapsopplysninger anses ofte som et enkelt, billig og bredt anvendelig alternativ til de klassiske ESG-vurderingssystemene som selges av leverandører av finansiell informasjon. Det finnes imidlertid ikke tilstrekkelig forskning på deres prediktive validitet. Målet med forskningen som presenteres i denne avhandlingen, var å undersøke (1) hvor godt klassiske ratingbaserte ESG-poengsummer kan predikeres ut fra NLP-baserte ESG-kontrovers-poengsummer, (2) om det prediktive forholdet varierer etter bransje, og (3) hvor konsistente effektene er når man sammenligner ulike tilnærminger for å konstruere ESG-kontrovers-poengsummer og ratingbaserte ESG-poengsummer. To studier ble gjennomført for å svare på disse spørsmålene. Studie 1 brukte data for OSX-noterte selskaper, hentet fra LSEG/Refinitiv Datastream. Studie 2 fokuserte på unoterte selskaper og reanalyserte et datasett utviklet av Kazinic og Valheim (2020). Resultatene fra studie 1 tyder på at LSEG/Refinitiv ESG-kontroverser ikke har noen vesentlig sammenheng med den faktiske LSEG/Refinitiv ESG-scoren; all forklarbar variasjon skyldtes globale forskjeller mellom bransjer. I finansiell analyse og porteføljeforvaltning ville en så lav prediktiv validitet helt klart være uakseptabel. Det kan derfor ikke anbefales å bruke LSEG/Refinitiv ESG-kontroversscoren som erstatning for klassiske, ratingbaserte ESG-scorer. Resultatene fra studie 2 tyder på at Kazinic og Valheims (2020) kontroversscore er vesentlig bedre enn LSEG/Refinitiv ESG-kontroversscoren, og at den er mye mindre påvirket av bransjeskjevhet, men at den fortsatt er utsatt for betydelig støy. Hvis Kazinic og Valheims kontroverspoeng skulle brukes som erstatning for faktiske ESG-poeng i porteføljeforvaltningen, ville den prediktive validiteten til kontroverspoengene likevel ikke være fullt ut tilstrekkelig. Tilnærmingen kan anbefales som et screeningverktøy i finansiell analyse, men kan ikke erstatte en dypere analyse av et selskaps faktiske ESG-profil før en investeringsbeslutning tas.ESG controversy scores based on natural language processing (NLP) of media coverage, ticker messages and corporate disclosures are often considered a simple, cheap and broadly applicable alternative to the classical ESG rating systems sold by financial information providers. However, there is insufficient research on their predictive validity. The aim of the research presented in this thesis was to investigate (1) how well classical rating-based ESG scores can be predicted from NLP-based ESG controversy scores, (2) if the predictive relationship differs by industry, and (3) how consistent the effects are when compared across different approaches for constructing ESG controversy scores and rating-based ESG scores. Two studies were conducted to address these questions. Study 1 used data for OSX-listed companies, extracted from LSEG/Refinitiv Datastream. Study 2 focused on unlisted companies, re-analysing a data set developed by Kazinic and Valheim (2020). The results of Study 1 suggest that the LSEG/Refinitiv ESG controversies score has no substantial relationship with the actual LSEG/Refinitiv ESG score; all explainable variation was due to global differences between industries. In financial analysis and portfolio management, such a low level of predictive validity would clearly be unacceptable. Using the LSEG/Refinitiv ESG controversies score as a replacement for classical, rating-based ESG scores cannot be recommended. The results of Study 2 indicate that the controversies scoring method developed by Kazinic and Valheim(2020) is substantially better than the LSEG/Refinitiv ESG controversies score and suffers much less from industry bias but is still subject to considerable noise. If Kazinic and Valheim’s controversies scores were to be used as a replacement of actual ESG scores in portfolio management, the predictive validity of the controversies scores would still not be fully sufficient. The approach can be recommended as a screening tool in financial analysis but cannot replace deeper analysis of a company’s actual ESG profile before an investment decision is made

Recovery of metals from highly concentrated acid mine drainage by liquid-liquid extraction

The growing consciousness and anxiety about the environment have motivated in the recent years extensive research aiming to develop new efficient technologies for the acid mine drainage (AMD) remediation. Such type of pollution is considered of serious concern because of its acidic nature (pH ranges around 2–4), and high concentrations of metals and sulfate. The AMD collected from the inactive São Domingos mine, Portugal for this work has the following concentrations of: 55.2 ± 0.4g/L Fe, 2.60 ± 0.03g/L Zn, 6.2 ± 0.1g/L Al, 4.60 ± 0.07g/L Cu and 123.9 ± 0.2mg/L Mn and 157.2 ± 3g/L of SO42-. The recovery of largely used metals such as, copper, zinc and iron, from this type of highly concentrated AMDs is still eco-unfriendly and expensive, thus new recovery strategies should be investigated. In this study, liquid-liquid extraction (LLE) process, involving commercial industrially known extractants and new extractants were tested for the recovery of copper, iron and zinc from the AMD collected at São Domingos mine. Accordingly, the extraction of copper by ACORGA M5640 and the subsequent stripping of the metal with H2SO4 solution were optimized. The results revealed that copper can be extracted from such AMD by 30% (v/v) ACORGA M5640 diluted in Shell GTL, making an 8/1 ratio of its active compound (5-nonyl-2-hydroxy-benzaldoxime) to copper ions, with an efficiency of 96 ± 3%. Copper was then efficiently stripped (95 ± 2%) from the metal loaded organic phase with a 2M H2SO4 solution. This organic phase has excellent reuse performance and can be recycled at least 5 times, according to this work and potentially much more times. Its maximum loading capacity of copper from AMD was determined to be 16.15 g/L and the accumulation of copper in the stripping solution in successive cycles reached 46 ± 3 g/L. After copper extraction, iron was successfully extracted from AMD 94 ± 2%) by an ionic liquid diluted in kerosene containing ions from Aliquat 336 and from Cyanex 272 (ALiCY) both in a 3/1 ratio to iron ions to prevent further iron co-extracted with zinc. Complete stripping of Fe (96 ± 2%) was achieved using also a 2M H2SO4 solution. As an alternative, it was confirmed that iron can be simply removed from AMD by adjusting the pH to values between 5 and 6. Concerning the subsequent recovery of zinc, 52 ± 2% was extracted using a synergistic mixture of 80% D2EHPA and 20% Cyanex 272 (with 18/1 and 4.5/1 ratios to zinc ions, respectively) diluted in kerosene with 3% Tributyl phosphate (TBP), and 99 ± 2% of this metal was then stripped from such organic phase once again with 2M H2SO4.A crescente consciencialização e preocupação acerca da poluição ambiental tem motivado um extenso esforço de investigação procurando o desenvolvimento de novas tecnologias de remediação de drenagem ácida de mina (DAM). Este tipo de poluição é considerado de grande preocupação devido à sua acidez (valores de pH entre 2 e 4) e elevadas concentrações de metais e sulfato. A DAM colhida para este trabalho na mina inativa de São Domingos, Portugal, tem as seguintes concentrações: 55.2 ± 0.4g/L Fe, 2.60 ± 0.03g/L Zn, 6.2 ± 0.1g/L Al, 4.60 ± 0.07g/L Cu and 123.9 ± 0.2 mg/L Mn and 157.2 g/L of SO42-. A recuperação de metais amplamente usados, como o cobre, o zinco e o ferro, deste tipo de DAMs altamente concentradas ainda é ecologicamente hostil e cara, sendo importante investigar novas estratégias de recuperação. Neste estudo foram testados processos de Extração Líquido-Líquido (ELL) com extratantes comerciais industrialmente conhecidos e com novos extratantes para a recuperação destes três metais da DAM colhida na mina de São Domingos. Assim, a extração de cobre com ACORGA M5640 e a subsequente reextração do metal com solução de H2SO4 foram otimizadas. Os resultados revelaram que o cobre pode ser extraído desta DAM com 30% (v/v) ACORGA M5640 diluído em Shell GTL, numa razão de 8/1 do seu composto ativo (5-nonyl-2-hydroxy-benzaldoxime) para iões de cobre, com uma eficiência de 96 ± 3%. O cobre foi depois eficientemente reextraído (95 ± 2%) da fase orgânica com uma solução de 2M H2SO4. De acordo com este trabalho, esta fase orgânica tem uma excelente capacidade de reutilização, podendo ser reciclada pelo menos 5 vezes e potencialmente muito mais vezes. A sua capacidade máxima de carregamento de cobre foi estimada em 16.15 g/L e a acumulação de cobre na solução de reextração em ciclos sucessivos chegou a 46 ± 3 g/L. Depois da extração de cobre, o ferro foi extraído da DAM com sucesso (94 ± 2%) com um líquido iónico diluído em querosene contendo iões provenientes de Aliquat 336 e Cyanex 272 (AliCy), ambos numa razão de 3/1 para os iões de ferro, para evitar posterior co-extração de ferro com o zinco. A reextração do ferro foi conseguida (96 ± 2%) também com uma solução de 2M H2SO4. Como alternativa confirmou-se que uma simples remoção do ferro da DAM é possível com um ajuste do pH para valores entre 5 a 6. No que respeita à subsequente recuperação do zinco, 52 ± 2% foram extraídos utilizando uma mistura sinérgica de 80% de D2EHPA e 20% de Cyanex 272 (com proporções de 18/1 e 4,5/1 para iões de zinco, respetivamente) diluídos em querosene com 3% de Fosfato de Tributilo (TBP), e em seguida 99 ± 2% deste metal foi reextraído desta fase orgânica mais uma vez com 2M H2SO4.I would like to thank European commission and, committee members and officials for the Master of Science program in Chemical Innovation and Regulation. The work was performed in the framework of project METALCHEMBIO (no. 29251) financed by national funds through the FCT – Foundation for Science and Technology and co-financed by the Algarve´s Regional Operational Program (CRESC Algarve 2020), through Portugal 2020 and European Regional Development Fund (FEDER

Treatability & Biogas Production Potential of Tannery Effluent in Anaerobic Sequential Batch Rectors from One of the Tannery Found in Addis Ababa, Ethiopia

Direct discharge of tannery effluent to the surrounding water bodies affects the water quality and further causes reduction and death of aquatic fauna and flora. The effect can be minimized by treatment of tannery effluent prior to discharge to the environment. Biological treatment method is cost effective and environmentally friendly than physicochemical treatment method. The objective of this study was to develop a laboratory scale anaerobic sequence batch reactor and evaluate the treatment efficiency and biogas production potential of chrome tanning effluent at mesophilic (37ᴼC±2) system. The study was conducted at five treatments (wastewater containing different concentration of chrome). The treatments (T-1 to T-5) contain chrome concentrations (Cr3+) 185mg/l, 120mg/l, 14mg/l and 6.85mg/l for T-1, T-2, T-3, T-4, and T-5 respectively. The hydraulic retention time of all treatments was three days and five days, the organic loading rate was wide-ranging between 1.49 kg COD/m3 /day for T-1 to 1.32 kg COD/m3/day forT-5 throughout the study. The removal efficiency of TS and VS of all treatments were in the range of 52-69% and 58-81%, respectively. The removal efficiency of COD,BOD,TN, NO3- , S-2, SO4 -2, PO4 3- and Cr3+ of all treatments were in the range of 42-62%,41-71%, 31-43%, 31-49%, 40-71%, 41-64%, 48-74% and 30-61% respectively. The maximum value of biogas at five days hydraulic retention time for (T-1 to T-5), (0.0089, 0.0097, 0.012, 0.027 and 0.034 m3 biogas/kg VS respectively) with methane content 21.1%, 22.7%, 37%, 51.3% and 54.7% was obtained after steady stable state condition. Hence, pretreated chrome tanning effluent with Cr (III) of 6.85mg/l was a potential feedstock for ASBR. Keywords: Anaerobic sequential batch reactor, Chrome Tanning Effluent, Biogas DOI: 10.7176/JETP/9-1-0

The changing pattern of diseases in the Mid 1990's: experience of a teaching hospital in North Western Ethiopia

Abstract: Between October 1994 and September 1995 consecutive adult medical admissions to the Gondar College of Medical Sciences (GCMS) teaching hospital were studied prospectively. The final diagnoses made or verified by consultant physicians before discharge or death were used for analysis. The median age was 30 years (range 12-98). Those below 50 and 40 years constituted 80.6% and 66.7%, respectively. Male to female ratio was 1.05:1.00. The median duration of hospital stay was 12 days (range 1-141). Tuberculosis and Insulin dependent Diabetes Mellitus were diseases associated with prolonged hospitalization, [OR, 95% CI = 4.66 (3.46, 6.29) and 2.4 (1.51, 3.83), respectively]. Of all admissions, 458 (40.2%) were screened for human immuno deficiency virus (HIV) and 232 (50.6%) were positive. The top ten diseases responsible for admissions, in order of decreasing frequency, were as follows: tuberculosis (25.4%), anaemia (6.5%), acute gastroenteritis and colitis (6.1%), diabetes mellitus (6.0%), pneumonia (5.9%), chronic diarrhea (4.96%), falciparum malaria (4.6%), chronic liver disease (4.2%), severe hypertension (4.2%), and stroke (3.0%). The mortality rate was 19.1%, which is high in comparison with similar reports from elsewhere. Tuberculosis and central nervous system diseases were the leading causes of hospital mortality, accounting for 35% and 18% of all deaths, respectively. There is a striking change in the pattern of diseases responsible for hospitalization compared to reports in the past. There is no study that revealed a single disease to be responsible for more than 20% of hospitalization except tuberculosis in this report. In addition, anaemia, chronic diarrhea, diabetes mellitus, hypertension, stroke and intracranial space occupying lesions were increasingly encountered. This marked change in pattern is partly explained by the current pandemic of human immuno deficiency virus/acquired immuno deficiency syndrome (HIV/AIDS) but other factors remain to be explained. [Ethiop. J. Health Dev. 1999;13(1):1-7

Probable HTLV-I/II Tropical Spastic Paraparesis Patient from Ethiopia: A Case Report

BACKGROUND: Available data on the burden of Human T-cell lymphotropic virus type I/II infection for eastern Africa, limited to Ethiopia, Mozambique, and Rwanda, show prevalence lower than elsewhere in Africa (0% - 1.8%). Even if Tropical Spastic Paraparesis occurs in an endemic form in Ethiopia, its seroprevalence is low. Over a lifetime, it is estimated that 1–2% of Human T-cell lymphotropic virus type I/ II  infected individuals will develop progressive and disabling inflammatory clinical manifestations. We are reporting this case since it signifies the existence of seropositive Tropical Spastic Paraparesis in our setting and the need to properly diagnose this condition.CASE PRESENTATION: We are reporting a 45 years old female patient from Addis Ababa, Ethiopia, who presented with progressive weakness of the lower limbs and urinary urge incontinence of five years duration. Serology for Human T-cell lymphotropic virus type I/ II antibody was positive. She was diagnosed to have probable tropical spastic paraparesis after fulfilling World Health Organization diagnostic criteria for tropical spastic paraparesis with the level of ascertainment. Symptoms showed transient improvements after providing five days of Methylprednisolone followed by low doses of corticosteroids and Azathioprine. The patient is now significantly disabled and wheelchair-bound.CONCLUSIONS: The patient described here signifies a probable Human T-cell lymphotropic virus type I/ II - associated myelopathy/ tropical spastic paraparesis in Ethiopian women. This case highlights the existence of Human T-cell lymphotropic virus type I/II - associated myelopathy/ tropical spastic paraparesis within our setting and the need to properly diagnose this condition

L’impact des nouvelles technologies de l’information sur la croissance française, 1980-2001

Cet article évalue la contribution des technologies de l’information à la croissance française au niveau macroéconomique. Nous mettons l’accent sur le rôle de la qualité du travail dans l’évolution de la productivité, notamment sur la période 1982-2001 et analysons les facteurs qui favorisent ou au contraire détériorent cette qualité.L’une des raisons, pour lesquelles la France et l’Allemagne restent en retrait des États-Unis et du Royaume-Uni en matière de contribution du capital lié aux technologies de l’information, est à rechercher non pas dans les taux de croissance mais dans les parts de l’investissement en technologies de l’information, la part américaine dans les investissements non résidentiels totaux étant deux fois plus élevée que les parts française et allemande.La contribution des technologies de l’information à la croissance de la productivité horaire s’est sensiblement élevée entre 1990-1995 et 1995-2001. Cette accélération, qui se double d’une hausse de la productivité multifactorielle ne s’est pas accompagnée d’une amélioration de la qualité du travail. Celle-ci a régulièrement augmenté en France jusqu’à la période 1990-1995, grâce à la contribution de l’éducation. Cependant, sur la dernière période, la baisse de la qualité du travail français est concomitante à la hausse des heures travaillées des catégories de travailleurs moins bien rémunérés, en particulier les jeunes.La différence d’accélération de la productivité multifactorielle entre la France et les États-Unis, favorable à la France sur la dernière période, témoigne de l’emploi accru aux États-Unis des intrants. La baisse du chômage des non-qualifiés tend par ailleurs à y modérer la contribution des diplômes à la qualité du travail sur la décennie quatre-vingt-dix par rapport à la décennie précédente.This paper quantifies the contribution of information technology (IT) to growth in France at the macro-level. On the labour side, the paper also provides evidence of the role played by hours worked, by stressing the contributions of various factors to labour quality and the way they affected labour productivity in the period 1995-2001.One of the reasons why France lags behind the U.S. in terms of the contribution to growth by information capital technology (ICT) is that although ICT investment growth was sustained as much in France as in the U.S., the proportion of U.S. ICT investment in total investments was more than twice as high as the French share.In France, the contribution of ICT to hourly labour productivity growth accelerated quite strongly over 1995-2001, relative to the previous period. This acceleration was indeed accompanied by an acceleration in total factor productivity but not by an increase in the quality of French labour. The latter did indeed increase regularly till the period 1990-1995, due largely to the contribution of education. Over the last period, the decrease in the quality of French labour was in synchrony with the fall in hours worked by older labour (> 54 years old) and the rise in hours worked by less well-paid workers and especially younger workers.The differential in multifactor productivity acceleration between France and the U.S., favouring France over the last period, illustrates the greater use of production factors in the United States. The decrease in unemployment of the unskilled people weighs there on the contribution of education to labour quality over the nineties relative to the eighties

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L’impact des nouvelles technologies de l’information sur la croissance française, 1980-2001

This paper quantifies the contribution of information technology (IT) to growth in France at the macro-level. On the labour side, the paper also provides evidence of the role played by hours worked, by stressing the contributions of various factors to labour quality and the way they affected labour productivity in the period 1995-2001. Cet article évalue la contribution des technologies de l’information à la croissance française au niveau macroéconomique. Nous mettons l’accent sur le rôle de la qualité du travail dans l’évolution de la productivité, notamment sur la période 1982-2001 et analysons les facteurs qui favorisent ou au contraire détériorent cette qualité.