Energy Level Tuning of Non-fullerene Acceptors in Organic Solar Cells

This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Journal of the American Chemical Society , copyright © American Chemical Society after peer review. To access the final edited and published work, see http://pubs.acs.org/doi/abs/10.1021/jacs.5b02808The use of non-fullerene acceptors in organic photovoltaic devices could lead to enhanced efficiencies due to increased open-circuit voltages (VOC) and improved absorption of solar light. Here we systematically investigate planar heterojunction devices comprising peripherally substituted subphthalocyanines as acceptor, and correlate device performance with heterojunction energetics. Due to a balance between VOC and photocurrent, tuning of the interface energy gap is necessary to optimize power conversion efficiency in these devices. In addition, we explore the role of the charge transport layers in the device architecture. It is found that non-fullerene acceptors require adjusted buffer layers with aligned electron transport levels to enable efficient charge extraction, while the insertion of an exciton blocking layer at the anode interface further boosts photocurrent generation. These adjustments result in a planar heterojunction OPV device with 6.9% efficiency and a VOC above 1 V.The research leading to these results has received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement 287818 of the X10D project and from the European Community’s ERC Advanced Grant # 320680 (EPOS CRYSTALLI). This work is also supported by the Spanish MINECO (CTQ-2014-52869-P) and Comunidad de Madrid (S2013/MIT-2841, FOTOCARBON

Effect of the Incorporation Level of Ripe Avocado Pulp Powder Persea americana on the Zootechnical Performances of Clarias jaensis Juveniles (Boulanger, 1909)

In order to contribute to the valorization of agricultural by-products in fish feed, the effect of the incorporation level of the ripe avocado pulp powder persea americana on the zootechnical performance of Clarias jaensis Juveniles (Boulanger, 1909), was studied between February and July 2019 in the highland zone of West Cameroon. To attend the aims, 156 juvenile Clarias jaensis (25.82 ± 7.43g) settled in triplicates in floating tanks were fed four iso-protein rations (40% crude protein) corresponding to 0, 8, 12 and 16% incorporation of ripe avocado. Feed were distributed twice daily (8 am and 6 pm) at 5% of the fish biomass for 63 days. The following results were as follows: Survival rate, final mean weight, daily mean weight gain, specific growth rate and condition factor K were higher and non-significant in batches receiving 8% of ripe avocado pulp powder with a lower feed conversion ratio (99,14 ± 0,50% ; 40,22 ± 10,5g; 0,14 ± 0,44 g/d, 0,41 ± 1,07 %g/d; 0,70 ± 0,09 %g/cm3 and 1,87 ± 0,09) and lower with a highest feed conversion ratio at 16% incorporation (93,67 ± 8,47 %; 30,02 ± 8,00g; 0,08 ± 0,22 g/d; 0,28 ± 0,77 % g /d; 0,68 ± 0,15 %g/cm3 and 2,018 ± 017). Body composition varied with the level of pulp meal incorporation, water content was high with 0% (79.14%), and dry matter (23.87%), crude protein (15.35%) and fat (5.23%). It was higher with 16%, while ash was higher (3.45%) in batches fed with 12% incorporation. The feed cost was lower at 8% incorporation (734.89Fcfa/kg of fish produced). The incorporation of 8% avocado pulp meal was found to improve the growth of Clarias jaensis juveniles and reduce the feed cost. Producers can use spoiled avocados as fish feed to reduce production costs, without negative impact on the final product

Performances de reproduction du poisson chat endogène du Cameroun Clarias jaensis (Boulenger, 1909) en milieu contrôlé

Les performances de reproduction de Clarias jaensis ont été évaluées entre mai et octobre 2014 à Batié (Ouest-Cameroun). A cet effet, 30 femelles de poids moyen 199, 52 ± 34,85 g ont été réparties en 5 lots comparables. Chaque lot choisi au hasard a été soumis à l’Hormone Chorionique Gonadotrophine (HCG) aux doses de 3500, 4000 et 4500 Unités Internationales (UI) / kg et aux extraits hypophysaires des mâles et des femelles. Le poids et le diamètre des ovocytes, les taux de fécondation et d’éclosion ont été évalués. Les principaux résultats ont montré que: le poids des ovocytes a été le plus élevé (p < 0, 05) avec l’extrait hypophysaire femelle (39,33±17,08g) ; le diamètre des ovocytes a été comparable entre les traitements. Le taux de fécondation a été le plus élevé pour la dose de 4000 UI / kg de HCG (87, 50 ± 12,45%) suivi de l’extrait hypophysaire femelle (85,08 ± 14,29%). Cependant aucune différence significative (p ˃ 0,05) n’a été obtenue. Le taux d’éclosion a été plus élevé avec l’extrait hypophysaire femelle (19, 38 ± 6,58%). La reproduction artificielle chez Clarias jaensis est possible avec l’hormone HCG à 4000 UI / kg ou des extraits hypophysaires femelles.© 2016 International Formulae Group. All rights reserved.Mots clés: Clarias jaensis, espèce endogène, performances de reproduction, captivité, CamerounEnglish Title:  Reproductive performances of indigenous catfish of Cameroon Clarias jaensis (Boulenger, 1909) in captivityEnglish AbstractIn order to improve local biodiversity and number of fishes in aquaculture in Cameroon, reproductive performances in captivity of Clarias jaensis have been studied between Mai and October 2014 in Batié (West Cameroon). In fact, 30 females with 199, 52 ± 34, 85 g were divided randomly into five comparable treatments. Each was submitted to a Human Chorionic Gonatropin Hormon at 3500, 4000 and 4500 Internationals Units (UI) / kg of body weight, males and female’s pituitary extracts. The main results obtained were: The oocyte weight was significantly higher (p < 0, 05) with females’ pituitary extracts (39, 33 ± 17,08g), the oocyte diameter mean was comparable within the treatments. The higher fecundity rate was obtained with the Human Chorionic Gonadotropin Hormon at 4000 UI / kg of body weight (85, 08 ± 14, 29%). However, no significant differences (p ˃ 0, 05) were found. The hatching rate was significantly higher (p < 0, 05) with the pituitary extracts of females (19, 38 ± 6, 58%). Clarias jaensis can be reproduced artificially using Human Chorionic Gonadotropin Hormon at 4000 UI / kg of body weight or female’s pituitary extracts.© 2016 International Formulae Group. All rights reserved.Keywords: Clarias jaensis, reproductive performances, indigenous species, captivity, Cameroo

Effect of concentrations of Artemia salina on zootechnical performances of Farfantepenaeus notialis in larval stages

Effect of concentrations of living food Artemia salina on survival and growth performances of marine shrimp Farfantepenaeus notialis (Pérez Farfante, 1967) from the Zoe 3 to Post larvae 1 stages, was carried out at AquaSol (Aquaculture Solidarité) structure in IRAD (Institute of Agricultural research for Development) of Kribi in Cameroon between July and August 2013. 3600 larvae (Zoe 3) born from a pregnant female (with total weight 70.6 g and 20 cm total length), collected in the natural environment by a fisherman using a bottom thread were used. The larvae were bred in an experimental device consisting of 6 treatments seeded in 3 replicates each. Treatments were randomly distributed into 18 cylinder-conical plastic bottles. Larvae were fed at different levels of concentration of imported Artemia salina nauplii (AN) (0 AN/ml, 1 AN/ml, 2 AN/ml, 3 AN/ml, 4 AN/ml and 5 NA/ml), Microalgae Thalassiossira pseudonana cultivated in the station and with a dry imported food. The best performances of survival, growth and metamorphosis were produced by 3 AN/ml concentrations of Artemia. The cost of food has increased with the concentration level of Artemia. Then, the production of viable shrimp post larvae and cheaper may be done at 3 AN/ml optimal concentrations of Artemia.Keywords: Biotic factors, Farfantepenaeus notialis, growth, survival, Cameroo

Reproductive Strategy of Chrysichthys nigrodigitatus (Lacepede, 1803) in a Natural Environment in the Nkam River, Littoral Cameroon

A study on the reproductive strategy of Chrysichthys nigrodigitatus was conducted from October 2015 to August 2016, in the Nkam River in Yabassi, Littoral Region of Cameroon. For this purpose, 154 specimens of C. nigrodigitatus with total mean weight of 829.96 ± 829.58 g and total mean length of 367 ± 156 mm collected from artisanal fishermen were used. Twenty-nine (29) females at stage V of sexual maturity were selected for the evaluation of the fecundity. It appears that the oogenesis in C. nigrodigitatus is of an asynchronous type with multiple laying spread over a long period. The gonadosomatic index (GSI) peaks in June (17.9 ± 7.1 for females and 1.06 ± 0.27 for males). Hepatosomatic index (HSI) was higher in females than in males throughout the year. The mean condition factor K was 1.07 ± 0.09%. The breeding season occurred from April to October during the rainy season. Gonadosomatic and hepatosomatic indices were positively correlated with rainfall, contrary to the K factor, which has been strongly and negatively correlated with this physical parameter. The sex ratio of 1M: 1.5F was in favour of females, thus reflecting an “r” type reproductive strategy. Absolute fecundity was estimated at 1374 ± 1022 oocytes for individuals of 107.3 ± 111.9 g mean weight. Mean relative fecundity was 14 ± 3 oocytes/g of body weight. It was recommended that future work focuses on the captivity of this species

Gastrointestinal helminths and external parasites of domestic rats trapped from residential areas within Maiduguri Municipality, Nigeria

A survey of domestic rats was conducted to investigate the prevalence of gastrointestinal helminths and external parasites in Maiduguri municipal between February and June 2015. Rats were randomly collected from residential sites within Maiduguri metropolis by trapping using mechanical and glue board traps.  Trapped rats were examined for external parasites, humanely sacrificed and subjected to detailed  postmortem examination for recovery of gastrointestinal helminths using standard methods. Parasites were identified using key morphological characteristics. Out of 85 rats sampled in the study, a total of 7(8.2%) were positive for gastrointestinal helminths. The only species of helminth identified was Hymenolepis  diminuta. There was no significant difference in prevalence of gastrointestinal helminths among different  age groups and sexes (P>0.05). The overall prevalence of ectoparasites was 9.4% and there was no  significant difference in prevalence rates among different age groups and sexes (P>0.05). The prevalence  of flea (5.9%) was higher than lice (3.5%). The two species of ectoparasites identified in the study were  Ctenocephalides canis (5.9%) and Polyplax spinulosa (3.5%). It was concluded from this study that  domestic rats trapped from Maiduguri harbor some species of endoparasites and ectoparasites which are  potentially zoonotic or may serve as vectors of important zoonotic pathogens.Keywords: Domestic rats, Ecto-parasites, Gastrointestinal helminths, Maiduguri, Prevalenc

Energy Level Tuning of Non-Fullerence Acceptors in Organic Solar Cells

The use of non-fullerene acceptors in organic photovoltaic (OPV) devices could lead to enhanced efficiencies due to increased open-circuit voltage (VOC) and improved absorption of solar light. Here we systematically investigate planar heterojunction devices comprising peripherally substituted subphthalocyanines as acceptors and correlate the device performance with the heterojunction energetics. As a result of a balance between VOC and the photocurrent, tuning of the interface energy gap is necessary to optimize the power conversion efficiency in these devices. In addition, we explore the role of the charge transport layers in the device architecture. It is found that non-fullerene acceptors require adjusted buffer layers with aligned electron transport levels to enable efficient charge extraction, while the insertion of an exciton-blocking layer at the anode interface further boosts photocurrent generation. These adjustments result in a planar-heterojunction OPV device with an efficiency of 6.9% and a VOC above 1 V.status: publishe

Performances comparées de survie et de croissance d’Oreochromis niloticus associé à Clarias jaensis et à Clarias gariepinus

La prolificité très élevé d’Oreochromis niloticus en étang cause l’augmentation de densité, la réduction de croissance et du rendement(1). L’élevage mono-sexe male ou l’association de Clarias gariepinus à Oreochromis niloticus est souvent pratiqué pour contrôler cette prolificité. Cependant, le sexage manuel présente des erreurs et la production à l’aide des hormones ou du choc thermique sont coûteux pour les pisciculteurs. Le caractère vorace de Clarias gariepinus est néfaste. L’utilisation d’autres Clariidae telle que Clarias jaensis, espèce endogène au Cameroun constituerait une solution tout en valorisant la biodiversité aquacole. C’est ainsi que de mars 2013 à février 2014 les performances de survie et de croissance de Oreochromis niloticus en monoculture, associé à Clarias jaensis et à Clarias gariepinus ont été étudiées à la Ferme d’Application et de Recherche de l’Université de Dschang (Latitude Nord : 5°24’ - 5°26’ et Longitude Est : 10°04’ - 10°07’), Ouest – Cameroun. A cet effet, 270 poissons dont 210 Oreochromis niloticus (17,52 ± 4,72g), 30 Clarias jaensis (16,85 ± 5,00g) et 30 Clarias gariepinus (15,66 ± 3,84g) ont été utilisés. Les poissons étaient stockés à 1,2 individus / m2 et répartis en trois traitements à trois répétitions dont Oreochromis niloticus en monoculture, Oreochromis niloticus associé à Clarias jaensis et Oreochromis niloticus associé à Clarias gariepinus en étangs fertilisés hebdomadairement aux fientes de poules. Au terme de l’essai, le taux de survie a été significativement (p ≤0,05) plus élevé chez Oreochromis niloticus associé à Clarias gariepinus en pré grossissement (75%) et chez Oreochromis niloticus associé à Clarias jaensis en grossissement (90%) ,le gain moyen quotidien a été plus élevé (au seuil de 95%) chez Oreochromis niloticus en monoculture et en association avec Clarias jaensis (0,31 ± 0,10g et 0,33 ± 0,15g/j). Le nombre d’alevins d’ Oreochromis niloticus produits a été significativement (P ≤ 0,05) plus faible dans l’association avec Clarias gariepinus. Ainsi, les performances de croissance et le rendement d’Oreochromis niloticus associé à Clarias jaensis ont été meilleurs qu’en monoculture. Clarias jaensis est un candidat potentiel pour l’amélioration de la production du Tilapia en contribuant à la diversification des espèces de Silure en élevage au Cameroun.Mots clés: Oreochromis niloticus, Clarias jaensis, Clarias gariepinus, monoculture, association, Performances de croissanceEnglish AbstractIn the fish farms of Cameroon in general, Clarias gariepinus is associated with Oreochromis niloticus in order to control the undesired prolificacy and increase growth a final yield. However, the voracious tendency of Clarias gariepinus with large prey sometimes leads to a decrease of the yield. The use of the less voracious species such as Clarias jaensis could be the way for preservation of endogenous fish species. Thus, the effect of types of catfish association in survival rate and growth performances of Oreochromis niloticus was tested between March 2013 and February 2014 at the Applied and Research Farm of the University of Dschang ( 24 ° 5 '- 5 ° 26 ' Northern and 10 ° 04' - 10 ° 07 'Eastern) in the Western High Lands of Cameroon. To achieve the assai 210 Oreochromis niloticus (17.52 ± 4.72g), 30 Clarias jaensis (16.85 ± 5.00 g) and 30 Clarias gariepinus (15.66 ± 3,84g) stored at 1 2 fish / m2, in three treatments and three replicates were used in ponds fertilized weekly with chicken droppings. The three treatments were Oreochromis niloticus associated with Clarias jaensis (T1), Oreochromis niloticus with Clarias gariepinus (T2) and Oreochromis niloticus in single culture (T3). The followings results were obtained: the survival rate in T1 and T2 was significantly (P ≤ 0.05) higher than T3 (90% and 75% against 50%). The average daily weight gain was higher for Oreochromis niloticus in monoculture and those associated with Clarias jaensis (0.31 ± 0.10 g and 0.33 ± 0.15 g / d). The number of fingerlings of Oreochromis niloticus produced was  significantly (P ≤ 0.05) low in association with Clarias gariepinus and those with Clarias jaensis. In general, the growth performances and reproduction control of Oreochromis niloticus associated with Clarias jaensis were higher than the monoculture.Keywords: Oreochromis niloticus, Clarias jaensis, Clarias gariepinus, monoculture, association, growth Performance

Willingness to participate in future HIV prevention trials in Beira, Mozambique

In preparation for trials of new HIV prevention methods, willingness to participate (WTP) was assessed in Beira, Mozambique. A totla of 1 019 women participating in an HIV incidence study, and 97 men participating in a separate WTP survey, were interviewed. When comparing the answers to questions that were identical in the two studies, WTP was higher among women than men for all prevention methods. Among women, WTP was highest for trials evaluating daily oral pre-exposure prophylaxis (PrEP; 84.4% reporting very likely to participate), followed by vaccination (77.8%), daily vaginal gel use (67.7%), coital vaginal gel use (67.1%) and monthly vaginal ring use (47.7%). Among men, WTP was highest for trials evaluating vaccination (57.6%), followed by daily vaginal gel use for female sexual partners (52.5%), daily oral PrEP (49.5%), coital vaginal gel use for female sexual partners (46.4%) and monthly vaginal ring use for female sexual partners (39.4%). Among men, the most important motivators for trial participation were social benefits, whereas personal risks (most notably receiving injections and/or blood draws) were deterrents; this was not assessed in women. Other important lessons learnt are that male circumcision and antiretroviral drugs were not generally recognised as ways to prevent HIV, that having to use hormonal contraception during trial participation will likely reduce WTP, and that evening clinics are not likely to be popular. The barriers reported in this and other studies may be challenging but are not impossible to overcome

Determinants of prevalent HIV infection and late HIV diagnosis among young women with two or more sexual partners in Beira, Mozambique

Background: The prevalence and determinants of HIV and late diagnosis of HIV in young women in Beira, Mozambique, were estimated in preparation for HIV prevention trials.Methods: An HIV prevalence survey was conducted between December 2009 and October 2012 among 1,018 women aged 18-35 with two or more sexual partners in the last month. Participants were recruited in places thought by recruitment officers to be frequented by women at higher-risk, such as kiosks, markets, night schools, and bars. Women attended the research center and underwent a face-to-face interview, HIV counseling and testing, pregnancy testing, and blood sample collection.Results: HIV prevalence was 32.6% (95% confidence interval (CI) 29.7%-35.5%). Factors associated with being HIV infected in the multivariable analysis were older age (p < 0.001), lower educational level (p < 0.001), self-reported genital symptoms in the last 3 months (adjusted odds ratio (aOR) = 1.4; CI 1.1-2.0), more than one lifetime HIV test (aOR = 0.4; CI 0.3-0.6), and not knowing whether the primary partner has ever been tested for HIV (aOR = 1.7; CI 1.1-2.5). About a third (32.3%) of participants who tested HIV-positive had a CD4 lymphocyte count o