Agronomic performance of four upland rice genotypes under rainfed condition

Upland rice fields cover up to 1.8 million hectares of the 4.7 million hectares of global rice fields, while farmers’ average yield of upland rice is far below the yield potential of existing traditional genotypes, particularly in West Africa. Grain yields of rice in Liberia are generally low, ranging from 0.5-1.5 tons per hectare (t/ha). A field study was conducted to evaluate yield and agronomic performances of four genotypes of rice (Nerica 8, Nerica 4, Arica 5 and LAC 23) on a typical fine sandy loam soil in the upper highland tropical forest agro-ecological Zone (UHTF AZ) of Liberia. The Randomized Complete Block Design (RCBD) was used with four replicates in four blocks. Data were taken on key agronomic characters including plant height; days to 50 % flowering; number of tillers; number of panicles; grain weight; panicle length; number of grains per plant; seed length and stem diameter at the base. Results from the Analysis of Variance (ANOVA) indicated that there were significant differences between the control (Lac 23) and the improved genotypes (Nerica 8, Arica 5 and Nerica 4) for all characters measured except for panicle length, seed length and stem diameter. Correlation analysis was also performed to establish extent of association between major yield components and grain yield. Days to 50 % flowering correlated significantly with plant height, number of tillers and number of panicles per plant. Nerica 8, Arica 5 and Nerica 4 recorded the highest yield and may, therefore, be recommended to smallholder farmers in the upper highland forest zone. Lac 23, Arica 5 and Nerica 8 may be recommended for local farmers, who prefer high yielding, and relatively medium heighted improved rice cultivars or their interspecific hybrids. This is because extremely tall rice genotypes are susceptible to lodging, particularly in stormy conditions that are prevalent in the upper highland tropical forest agro-ecological zone of Liberia. Other approaches may be required to test these cultivars under harsh environments (such as water deficit condition) and different agroecologies across the country. We also recommend organoleptic assessments of Nerica 4, Nerica 8 and Arica 5 to boost their acceptability among consumers in the country.Keywords: Upland rice, agronomic performance, improved genotypes, Nerica, correlation, Liberi

Health-related quality of life among Ebola survivors in Sierra Leone: the role of socio-demographic, health-related and psycho-social factors.

BACKGROUND: Evidence of how social factors affect the health-related quality of life (HRQoL) of Ebola virus disease (EVD) survivors is limited. Our study explores the association between socio-demographic, health-related and psycho-social (stigma) factors and EVD survivors' health-related quality of life (HRQoL) in Sierra Leone. METHODS: We conducted a nationwide cross-sectional study among 358 EVD survivors between January and August 2018. We used a multistage sampling method to recruit EVD survivors, and the RAND 36-Item Health Survey item was used to assess the HRQoL. Data were analysed using descriptive statistics and multiple linear regression. RESULTS: When comparing by each dimension in relation to their respective summary scores, role limitation physical [0.00 (50.00)] and role limitation emotional [0.00 (33.33)] were the most affected physical health and mental health domains among EVD survivors respectively. EVD survivors who were older (β = - 3.90, 95% CI - 6.47 to - 1.32, p = 0.003), had no formal education (β = - 2.80, 95% CI - 5.16 to - 0.43, p = 0.021), experienced a unit increase in the number of post-Ebola symptoms (β = - 1.08, 95% CI - 1.74 to - 0.43, p < 0.001) and experienced a unit increase in enacted stigma (β = - 2.61, 95% CI - 4.02 to - 1.20, p < 0.001) were more likely to report a decreased level of physical health. EVD survivors who experienced a unit increase in the time spent in the Ebola treatment centre (β = - 0.60, 95% CI - 0.103 to - 0.18, p = 0.006) and those who experienced a unit increase in enacted Stigma were more likely to report decreased levels of mental health (β = - 1.50, 95% CI - 2.67 to - 0.33, p = 0.012). CONCLUSION: Sociodemographic, health-related, and psycho-social factors were significantly associated with decrease levels of HRQoL. Our findings improve our understanding of the factors that might influence the HRQoL and suggest the need for EVD survivors to be provided with a comprehensive healthcare package that caters for their physical and mental health needs

Symptom- and Laboratory-Based Ebola Risk Scores to Differentiate Likely Ebola Infections.

Rapidly identifying likely Ebola patients is difficult because of a broad case definition, overlap of symptoms with common illnesses, and lack of rapid diagnostics. However, rapid identification is critical for care and containment of contagion. We analyzed retrospective data from 252 Ebola-positive and 172 Ebola-negative patients at a Sierra Leone Ebola treatment center to develop easy-to-use risk scores, based on symptoms and laboratory tests (if available), to stratify triaged patients by their likelihood of having Ebola infection. Headache, diarrhea, difficulty breathing, nausea/vomiting, loss of appetite, and conjunctivitis comprised the symptom-based score. The laboratory-based score also included creatinine, creatine kinase, alanine aminotransferase, and total bilirubin. This risk score correctly identified 92% of Ebola-positive patients as high risk for infection; both scores correctly classified >70% of Ebola-negative patients as low or medium risk. Clinicians can use these risk scores to gauge the likelihood of triaged patients having Ebola while awaiting laboratory confirmation

An Assessment of Medication Errors Among Pediatric Patients in Three Hospitals in Freetown Sierra Leone: Findings and Implications for a Low-Income Country

Onome T Abiri,1,2 Alex Ninka,3 Joshua Coker,4 Fawzi Thomas,2,5 Isaac O Smalle,6 Sulaiman Lakoh,4 Foday Umaro Turay,7 James Komeh,2,3 Mohamed Sesay,2,7 Joseph Sam Kanu,8 Ayeshatu M Mustapha,9 Nellie VT Bell,9 Thomas Ansumus Conteh,2,5 Sarah Kadijatu Conteh,10 Alhaji Alusine Jalloh,10 James BW Russell,4 Noah Sesay,3 Mohamed Bawoh,1 Mohamed Samai,1 Michael Lahai7 1Department of Pharmacology and Therapeutics, College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone; 2Department of Pharmacovigilance and Clinical Trials, Pharmacy Board of Sierra Leone, Freetown, Sierra Leone; 3Department of Clinical Pharmacy and Therapeutics, College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone; 4Department of Internal Medicine, College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone; 5Department of Pharmaceutics, College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone; 6Department of Surgery, College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone; 7Department of Pharmaceutical Chemistry, College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone; 8Department of Community Medicine, College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone; 9Department of Pediatrics, Ola During Children Hospital, Freetown, Sierra Leone; 10Department of Pediatrics, King Harman Road Maternity and Children Hospital, Freetown, Sierra LeoneCorrespondence: Onome T Abiri, Department of Pharmacology and Therapeutics, College of Medicine and Allied Health Sciences, University of Sierra Leone Freetown, Sierra Leone/Department of Pharmacovigilance and Clinical Trials, Pharmacy Board of Sierra Leone, Freetown, Sierra Leone, Tel +23276370315, Email [email protected]: Pediatric patients are prone to medicine-related problems like medication errors (MEs), which can potentially cause harm. Yet, this has not been studied in this population in Sierra Leone. Therefore, this study investigated the prevalence and nature of MEs, including potential drug-drug interactions (pDDIs), in pediatric patients.Methods: The study was conducted in three hospitals among pediatric patients in Freetown and consisted of two phases. Phase one was a cross-sectional retrospective review of prescriptions for completeness and accuracy based on the global accuracy score against standard prescription writing guidelines. Phase two was a point prevalence inpatient chart review of MEs categorized into prescription, administration, and dispensing errors and pDDIs. Data was analyzed using frequency, percentages, median, and interquartile range. Kruskal–Wallis H and Mann–Whitney U-tests were used to compare the prescription accuracy between the hospitals, with p< 0.05 considered statistically significant.Results: Three hundred and sixty-six (366) pediatric prescriptions and 132 inpatient charts were reviewed in phases one and two of the study, respectively. In phase one, while no prescription attained the global accuracy score (GAS) gold standard of 100%, 106 (29.0%) achieved the 80– 100% mark. The patient 63 (17.2%), treatment 228 (62.3%), and prescriber 33 (9.0%) identifiers achieved an overall GAS range of 80– 100%. Although the total GAS was not statistically significant (p=0.065), the date (p=0.041), patient (p=< 0.001), treatment (p=0.022), and prescriber (p=< 0.001) identifiers were statistically significant across the different hospitals. For phase two, the prevalence of MEs was 74 (56.1%), while that of pDDIs was 54 (40.9%). There was a statistically positive correlation between the occurrence of pDDI and number of medicines prescribed (r=0.211, P=0.015).Conclusion: A Low GAS indicates poor compliance with prescription writing guidelines and high prescription errors. Medication errors were observed at each phase of the medication use cycle, while clinically significant pDDIs were also reported. Thus, there is a need for training on prescription writing guidelines and medication errors.Keywords: pediatrics, prescription, medication errors, drug-drug interactions, Sierra Leon

Awareness of school students on sexually transmitted infections (STIs) and their sexual behavior: a cross-sectional study conducted in Pulau Pinang, Malaysia

<p>Abstract</p> <p>Background</p> <p>Sexually transmitted Infections (STIs) rank among the most important health issues for the people especially the young adults worldwide. Young people tend to engage in sexual activity at younger ages in the past decade than in the 1970s, and 1980s. Knowledge is an essential precursor of sexual risk reduction. A cross-sectional study was conducted in Pulau Pinang, Malaysia, to produce the baseline information about school students' awareness and perception about sexually transmitted Infections (STIs) and their sexual activity to help establish control and education programmes.</p> <p>Methods</p> <p>Students from form 4 (aged between 15 to 16 years), form 5 (aged between 16 to 17 years) and form 6 (aged between 18 to 20 years) in their class rooms were approached and asked to complete self administered and anonymous pre-validated questionnaires. SPSS for windows version 13 was used to analyze the results statistically and results were presented in tabular form.</p> <p>Results</p> <p>Data was collected from 1139 students aged between 15 to 20 years, 10.6% of which claimed that they never heard about STIs. Sexual experience related significantly with gender, race, and education level. Approximately 12.6% claimed to have sexual experience of which 75.7% had their sexual debut at 15-19 years and 38.2% were having more than 3 partners. Sexual experience was found to be significantly associated with gender (<it>p </it>= 0.003), ethnicity (<it>p </it>= 0.001) and education level (<it>p </it>= 0.030). However, multiple partner behaviour was significantly associated only with gender (<it>p </it>= 0.010). Mean knowledge score was 11.60 ± 8.781 and knowledge level was significantly associated with religion (p = 0.005) education level (<it>p </it>= 0.000), course stream (<it>p </it>= 0.000), socioeconomic class (<it>p </it>= 0.000) and sexual experience (<it>p </it>= 0.022).</p> <p>Conclusions</p> <p>It was concluded that school students have moderate level of knowledge about STIs although they are sexually active. Interventions such as reinforcing the link between STIs and HIV/AIDS, assessing the current status of sexuality education in schools and arranging public talks and seminars focusing on STIs prevention education are needed to improve their awareness.</p

Safety and immunogenicity of the two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in children in Sierra Leone: a randomised, double-blind, controlled trial

Background—Children account for a substantial proportion of cases and deaths from Ebola virus disease. We aimed to assess the safety and immunogenicity of a two-dose heterologous vaccine regimen, comprising the adenovirus type 26 vector-based vaccine encoding the Ebola virus glycoprotein (Ad26.ZEBOV) and the modified vaccinia Ankara vectorbased vaccine, encoding glycoproteins from the Ebola virus, Sudan virus, and Marburg virus, and the nucleoprotein from the Tai Forest virus (MVA-BN-Filo), in a paediatric population in Sierra Leone. Methods—This randomised, double-blind, controlled trial was done at three clinics in Kambia district, Sierra Leone. Healthy children and adolescents aged 1–17 years were enrolled in three age cohorts (12–17 years, 4–11 years, and 1–3 years) and randomly assigned (3:1), via computer-generated block randomisation (block size of eight), to receive an intramuscular injection of either Ad26.ZEBOV (5 × 1010 viral particles; first dose) followed by MVA-BN-Filo (1 × 108 infectious units; second dose) on day 57 (Ebola vaccine group), or a single dose of meningococcal quadrivalent (serogroups A, C, W135, and Y) conjugate vaccine (MenACWY; first dose) followed by placebo (second dose) on day 57 (control group). Study team personnel (except for those with primary responsibility for study vaccine preparation), participants, and their parents or guardians were masked to study vaccine allocation. The primary outcome was safety, measured as the occurrence of solicited local and systemic adverse symptoms during 7 days after each vaccination, unsolicited systemic adverse events during 28 days after each vaccination, abnormal laboratory results during the study period, and serious adverse events or immediate reportable events throughout the study period. The secondary outcome was immunogenicity (humoral immune response), measured as the concentration of Ebola virus glycoprotein-specific binding antibodies at 21 days after the second dose. The primary outcome was assessed in all participants who had received at least one dose of study vaccine and had available reactogenicity data, and immunogenicity was assessed in all participants who had received both vaccinations within the protocol-defined time window, had at least one evaluable post-vaccination sample, and had no major protocol deviations that could have influenced the immune response. This study is registered at ClinicalTrials.gov, NCT02509494. Findings—From April 4, 2017, to July 5, 2018, 576 eligible children or adolescents (192 in each of the three age cohorts) were enrolled and randomly assigned. The most common solicited local adverse event during the 7 days after the first and second dose was injection-site pain in all age groups, with frequencies ranging from 0% (none of 48) of children aged 1–3 years after placebo injection to 21% (30 of 144) of children aged 4–11 years after Ad26.ZEBOV vaccination. The most frequently observed solicited systemic adverse event during the 7 days was headache in the 12–17 years and 4–11 years age cohorts after the first and second dose, and pyrexia in the 1–3 years age cohort after the first and second dose. The most frequent unsolicited adverse event after the first and second dose vaccinations was malaria in all age cohorts, irrespective of the vaccine types. Following vaccination with MenACWY, severe thrombocytopaenia was observed in one participant aged 3 years. No other clinically significant laboratory abnormalities were observed in other study participants, and no serious adverse events related to the Ebola vaccine regimen were reported. There were no treatment-related deaths. Ebola virus glycoprotein-specific binding antibody responses at 21 days after the second dose of the Ebola virus vaccine regimen were observed in 131 (98%) of 134 children aged 12–17 years (9929 ELISA units [EU]/mL [95% CI 8172–12 064]), in 119 (99%) of 120 aged 4–11 years (10 212 EU/mL [8419–12 388]), and in 118 (98%) of 121 aged 1–3 years (22 568 EU/mL [18 426–27 642]). Interpretation—The Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen was well tolerated with no safety concerns in children aged 1–17 years, and induced robust humoral immune responses, suggesting suitability of this regimen for Ebola virus disease prophylaxis in children

Safety and long-term immunogenicity of the two-dose heterologous Ad26.ZEBOV and MVA-BN-Filo Ebola vaccine regimen in adults in Sierra Leone: a combined open-label, non-randomised stage 1, and a randomised, double-blind, controlled stage 2 trial

Background The Ebola epidemics in west Africa and the Democratic Republic of the Congo highlight an urgent need for safe and effective vaccines to prevent Ebola virus disease. We aimed to assess the safety and long-term immunogenicity of a two-dose heterologous vaccine regimen, comprising the adenovirus type 26 vector-based vaccine encoding the Ebola virus glycoprotein (Ad26.ZEBOV) and the modified vaccinia Ankara vector-based vaccine, encoding glycoproteins from Ebola virus, Sudan virus, and Marburg virus, and the nucleoprotein from the Tai Forest virus (MVA-BN-Filo), in Sierra Leone, a country previously affected by Ebola. Methods The trial comprised two stages: an open-label, non-randomised stage 1, and a randomised, double-blind, controlled stage 2. The study was done at three clinics in Kambia district, Sierra Leone. In stage 1, healthy adults (aged ≥18 years) residing in or near Kambia district, received an intramuscular injection of Ad26.ZEBOV (5×1010 viral particles) on day 1 (first dose) followed by an intramuscular injection of MVA-BN-Filo (1×108 infectious units) on day 57 (second dose). An Ad26.ZEBOV booster vaccination was offered at 2 years after the first dose to stage 1 participants. The eligibility criteria for adult participants in stage 2 were consistent with stage 1 eligibility criteria. Stage 2 participants were randomly assigned (3:1), by computer-generated block randomisation (block size of eight) via an interactive web-response system, to receive either the Ebola vaccine regimen (Ad26.ZEBOV followed by MVA-BN-Filo) or an intramuscular injection of a single dose of meningococcal quadrivalent (serogroups A, C, W135, and Y) conjugate vaccine (MenACWY; first dose) followed by placebo on day 57 (second dose; control group). Study team personnel, except those with primary responsibility for study vaccine preparation, and participants were masked to study vaccine allocation. The primary outcome was the safety of the Ad26.ZEBOV and MVA-BN-Filo vaccine regimen, which was assessed in all participants who had received at least one dose of study vaccine. Safety was assessed as solicited local and systemic adverse events occurring in the first 7 days after each vaccination, unsolicited adverse events occurring in the first 28 days after each vaccination, and serious adverse events or immediate reportable events occurring up to each participant’s last study visit. Secondary outcomes were to assess Ebola virus glycoprotein-specific binding antibody responses at 21 days after the second vaccine in a per-protocol set of participants (ie, those who had received both vaccinations within the protocol-defined time window, had at least one evaluable post-vaccination sample, and had no major protocol deviations that could have influenced the immune response) and to assess the safety and tolerability of the Ad26.ZEBOV booster vaccination in stage 1 participants who had received the booster dose. This study is registered at ClinicalTrials.gov, NCT02509494. Findings Between Sept 30, 2015, and Oct 19, 2016, 443 participants (43 in stage 1 and 400 in stage 2) were enrolled; 341 participants assigned to receive the Ad26.ZEBOV and MVA-BN-Filo regimen and 102 participants assigned to receive the MenACWY and placebo regimen received at least one dose of study vaccine. Both regimens were well tolerated with no safety concerns. In stage 1, solicited local adverse events (mostly mild or moderate injection-site pain) were reported in 12 (28%) of 43 participants after Ad26.ZEBOV vaccination and in six (14%) participants after MVA-BN-Filo vaccination. In stage 2, solicited local adverse events were reported in 51 (17%) of 298 participants after Ad26.ZEBOV vaccination, in 58 (24%) of 246 after MVA-BN-Filo vaccination, in 17 (17%) of 102 after MenACWY vaccination, and in eight (9%) of 86 after placebo injection. In stage 1, solicited systemic adverse events were reported in 18 (42%) of 43 participants after Ad26.ZEBOV vaccination and in 17 (40%) after MVA-BN-Filo vaccination. In stage 2, solicited systemic adverse events were reported in 161 (54%) of 298 participants after Ad26.ZEBOV vaccination, in 107 (43%) of 246 after MVA-BN-Filo vaccination, in 51 (50%) of 102 after MenACWY vaccination, and in 39 (45%) of 86 after placebo injection. Solicited systemic adverse events in both stage 1 and 2 participants included mostly mild or moderate headache, myalgia, fatigue, and arthralgia. The most frequent unsolicited adverse event after the first dose was headache in stage 1 and malaria in stage 2. Malaria was the most frequent unsolicited adverse event after the second dose in both stage 1 and 2. No serious adverse event was considered related to the study vaccine, and no immediate reportable events were observed. In stage 1, the safety profile after the booster vaccination was not notably different to that observed after the first dose. Vaccine-induced humoral immune responses were observed in 41 (98%) of 42 stage 1 participants (geometric mean binding antibody concentration 4784 ELISA units [EU]/mL [95% CI 3736–6125]) and in 176 (98%) of 179 stage 2 participants (3810 EU/mL [3312–4383]) at 21 days after the second vaccination. Interpretation The Ad26.ZEBOV and MVA-BN-Filo vaccine regimen was well tolerated and immunogenic, with persistent humoral immune responses. These data support the use of this vaccine regimen for Ebola virus disease prophylaxis in adults

Leaf Chlorophyll Content and Tuberous Root Yield of Cassava in Inland Valley

Two field trials were established in 1996 and 1997 to assess genotypic variability of four cassava (Manihot esculanta) cultivars for adaptability in the inland valley in terms of leaf chlorophyll content and tuberous root yield, using a 4 x 4 Latin square design with four replications arranged along the toposequence. Leaf chlorophyll a, b and ab contents and root yield of the improved cultivars were similar, but were significantly greater than those of Isunikankiyan, the local cultivar. Plants in the valley fringe had the highest concentrations of the three chlorophyll components and root yield. Leaf chlorophyll a and ab contents and root yield were significantly higher in 1996 than in 1997, due partly to favourable weather conditions in 1996. However, the reverse was the case for leaf chlorophyll b content, suggesting that chlorophyll b concentration may increase under stressful conditions. Root yield in all cultivars increased with increase in concentration of the three leaf chlorophyll components, but chlorophyll a and ab were more correlated with yield than chlorophyll b. Correlation between chlorophyll contents and root yield were strongest for TMS 91/02324 with the highest root yield, and weakest for Isunikankiyan, the lowest yielder. Root yield of the four cultivars and concentrations of the three chlorophyll components decreased linearly as the groundwater table depth became shallow. Therefore, selection of cassava cultivars that can maintain high leaf chlorophyll contents under moisture stress can lead to high root yield when combined with other yield determinants in inland valleys. Key Words: Ground water table, improved cultivars, moisture stress, Nigeria Résumé Les essais de terrain étaient établis en 1996 et 1997 pour déterminer la variabilité génotypique de quatre variétés de manioc (Manihot esculenta) en adaptabilité dans les vallées en termes du contenu en chlorophile dans les feuilles et le rendement en tubercules, utilisant un arrangement 4x4 carré latin avec quatre replications sur la toposéquence. Les contenus de chlorophiles a, b, et ab dans les feuilles et dans les racines des variétés améliorées étaient similaires, mais étaient significativement grande par raport à la variété locale Isunikankiyan. Les plantes dans les vallées avaient des concentrations élévées de trois composantes du chlorophiles et le rendement en racines. Les contenues en chlorophiles a et ab et le rendement en racines étaient significativement élévés en 1996 par raport à 1997, probablement à cause des conditions climatiques en 1996. Cependant, l\'inverse était observé pour le contenu en chlorophile b dans les feuilles, suggérant que la concentration en chlorophile peut augmenté dans les conditions de stress. Le rendement en racines a augmenté pour toutes les variétés avec une augmentation de concentration de composantes de chlorophiles, avec une corrélation élévée pour les chlorophiles a et ab. La corrélation entre le contenu en chlorophile et le rendement en racine était plus élévée pour TMS 91/12324 qui avait aussi le plus grand rendement. Isunikankiyan avait une faible corrélation et un faible rendement. Le rendement en racine de quatre variétés et les concentrations de trois composantes de chlorophiles diminué linéairement avec l\'abaissement du niveau d\'eau dans le sol. Par conséquent, la sélection de variétés du manioc qui peut maintenir les niveaux de chlorophiles élévés sous des conditions d\'humidité déficientes peut conduire à des rendements élévés quand combiné avec d\'autres determinants de rendements dans les vallées. Mots Clés: Niveau d\'eau dans le sol, variété améliorée, stress d\'humidité, Nigeria (Af Crop Sci J 2003 Vol 11 No 2 pp.107-117

Mechanical and Thermal Properties of Poly(urethane urea) Nanocomposites Prepared with Diamine-Modified Laponite

Nanocomposites based on segmented poly(urethane urea) were prepared by reacting a poly(diisocyanate) with diamine-modified Laponite-RD nanoparticles that served as a chain extender. The nanocomposites were prepared at a constant NH2 to NCO mole ratio of 0.95, while varying the fraction of diamine-modified Laponite relative to the free diamine chain extender. Compared to neat poly(urethane urea), all nanocomposites showed increased tensile strength and elongation at break. As Laponite loading increased, tensile properties passed through a maximum at a particle concentration of 1 mass%, at which a 300% increase in tensile strength and 40% increase in elongation at break were observed. A maximum in urea and urethane hard-domain melting endotherms was also observed at this Laponite loading. Optimal mechanical and thermal properties coincided with a minimum in the size of the inorganic Laponite phase. Nanocomposites containing diamine-modified Laponite had higher tensile strengths than those with nonreactive monoamine-modified Laponite or diamine-modified Cloisite