Feeding the soil to feed the planet: soil health outcomes from novel amendments to residue management

2021 Summer.Includes bibliographical references.Healthy soils are the foundation for the continued capacity of agricultural lands to supply essential ecosystem services while also meeting demands for food, fuel and fiber. From academia to policymakers and other key stakeholders, attention towards soil health continues to rise due to global environmental challenges such as climate change and food security that can be potentially mitigated through the sustainable and innovative management of soils. Specifically, the application of organic inputs including composts and animal manures can help enhance water holding capacity, organic matter accumulation and crop production. However, the heterogeneous nature of soils and diversity of production systems precludes a single ‘silver bullet' solution to optimize soil health. In addition, outstanding questions persist on the differences in spatiotemporal effects of different organic inputs and their application frequency as well as the linkages between different soil health properties. This dissertation examines soil health under two different organic input management regimes including a novel soil amendment derived from cheese manufacturing as well as corn residue management in semi-arid agroecosystems. Both the novel soil amendment and corn residue management approaches were established with the goal of conserving soil water in these water limited systems. The novel soil amendment approach involved the one-time, direct application of a byproduct from cheese production known as lactobionate (LB) to soils through an agronomic trial irrigated with wheat and corn. I found that LB applied to soils increased the water retention capacity as well as the microbial biomass content of soils in the 5-15 cm soil zone under the wheat trial. I also found a non-statistically significant 14% increase in corn yield for LB-amended plots. However, I did not observe any difference in wheat yield and some soil properties (soil pH, soil carbon (C), soil nitrogen (N), and soil ammonium concentration for both trials) with lactobionate addition. My observations suggest the potential for lactobionate to modify soil water content, microbial biomass, nitrate, and yield but outcomes varied by crop trial and amendment rates. This implies that while recycling industrial food processing waste for use as a soil amendment may have benefits for key soil properties, the timing, mode and application rate need to be optimized for maximal effects on soil properties. Due to the effect of LB on soil health observed in the field trials, I conducted an 84-day laboratory incubation experiment to understand specific mechanisms of how LB influences soil organic matter (SOM) decomposition and accumulation via different SOM fractions. I collected soils from the field and split them to add 13C lactobionate to some soils and water only to other soils. I found that about 53% of added lactobionate was respired over 84 days, and observed a positive priming effect after 14 days. In response to LB addition, the total C content of the water extractable organic matter (WEOM) fraction increased by 100% at the initial stage of the incubation but declined exponentially and quicker than other SOM fractions. In addition, the total C content of the light-fraction particulate organic matter (LF-POM) fraction also declined, while both the sand-sized POM and mineral-associated organic (MAOM) C fractions strongly increased relative to unamended control. My results suggest that while lactobionate can help improve soil water retention, it also presents an avenue to building more persistent C through its impacts on the internal cycling of SOM fractions and more importantly on the mineral-associated organic matter fraction considered more relevant to SOC long-term persistence and relative resilience to disturbance. The corn residue management study included a four-treatment combination of residue management (residue retained versus residue harvested) and tillage (no-tillage versus conventional tillage) implemented in the field consistently for 6 years, in contrast to the one-time application of lactobionate. My results showed that the most significant differences across soil properties measured were more apparent at the 0-10 cm zone and were mainly driven by residue retention with minor tillage effects. Regardless of tillage mode employed, retaining residues in the 0-10 cm soil layer led to higher soil water content, soil C, aggregate stability, available phosphate, soil macrofauna and fungal abundance and diversity. Furthermore, residue retention was the main driver of macrofauna and microbial community composition; however, an interaction between tillage and residue management suggested that the effect of tillage on microbial communities was most pronounced when residues were retained. I also found significant covariation between soil physicochemical, macrofauna and microbial datasets, indicating a strong association between different soil properties and cascading effects of management on multiple soil properties. Overall, my findings suggest the impact of both novel amendment and corn residue inputs on soil health varied with application strategy, as the corn residues applied consistently for 6 years had a stronger effect on soil health in the top layer of soils (0 – 15 cm) as compared to lactobionate which was applied one-time. Certain soil properties also responded more quickly to management as compared to others. In addition, while organic inputs are usually applied to target a specific soil health property, other soil health elements can also be affected in a similar magnitude and direction due to latent linkages between different soil properties

Effect of Pregnancy and Childbirth on Sexuality of Women in Ibadan, Nigeria

A study of 375 antenatal attendees to assess women's views and experience in sexual matters during pregnancy and following childbirth. Explanatory variables included the perception women had of sex during pregnancy and after childbirth. Outcome variables were frequency and satisfaction of sexual activity. The commonest reasons for having coitus in pregnancy were marital harmony and facilitation of delivery. Libido rose throughout pregnancy but orgasms were less often experienced. The man-on-top position became less practised. Vaginal intercourse remained the commonest type. Masturbation and anal intercourse increased, while oral sex declined throughout. Marriage (OR 9.0, 95% CI 1.0–79.5) and current cohabitation (OR 13.6, 95% CI 1.6–113.4) were predictors of sex in pregnancy. Dyspareunia and partners' extramarital affairs were deterrent. Vaginal delivery and episiotomy were not significant predictors of postnatal sex. The respondents and their partners seem able to adapt to pregnancy changes and enhance their marital bonds. Anticipatory guidance and informed counselling may encourage this

Challenges of diagnosing and managing bronchiectasis in resource-limited settings: a case study

Bronchiectasis, once an orphan disease is now gaining renewed attention as a significant cause of morbidity and mortality. It is a morphologic term used to describe abnormal, irreversibly dilated and thick-walled bronchi, with many etiologies. The management of bronchiectasis can be challenging because its pathogenetic mechanisms is still evolving. Its diagnosis and management is particularly more demanding especially in resource-limited settings like Nigeria because of delayed diagnosis and improper management with devastating consequences, hence this case study

Significant Bacteriuria Among Asymptomatic Antenatal Clinic Attendees In Ibadan, Nigeria

Untreated asymptomatic bacteriuria can lead to urinary tract infection (UTI) in pregnancy with devastating maternal and neonatal effects such as prematurity and low birth weight, higher fetal mortality rates and significant maternal morbidity. We carried out a two year (April 2007 to March 2009) cross-sectional epidemiological study to determine the prevalence of significant bacteriuria among asymptomatic antenatal clinic attendees at two antenatal clinics (ANCs) in University College Hospital and Adeoyo Maternity Hospital, both in Ibadan, Nigeria

Laminar Forced Convective Heat Transfer and Fluid Flow in a Finned Cylindrical Annulus

The purpose of this paper is to numerically investigate the effects of some geometric parameters and flow variables on heat transfer augmentation in annuli with equi-spaced internal longitudinal fins along the external walls. A fully developed flow and a constant thermal boundary condition of uniform heat flux at the walls of the pipe were assumed. Continuity, momentum and energy transport equations were adopted for the solutions of the problem. A Q-BASIC code was written based on the finite difference scheme generated. Numerical experiments were conducted to ascertain the effects of Reynolds number Re, radius ratio, R.R, Prandtl number Pr, fin height H, and pipe inclination, on the rate of heat transfer and fluid flow. The results obtained show that for 50 ≤ Re ≤ 500, total Nusselt number NuT increases with increase in Re while for Re > 500, there was no significant increase in NuT. Nusselt number, average velocity and bulk temperature of the fluid increase with increasingin the range 0° ≤ ≤ 75° but for the range 75°≤  ≤ 90°  the effect is negligible. For R.R > 0.6, the heat transfer was observed to be almost independent of R; therefore for economic purposes, heat exchangers similar to the configuration studied should be run at a low pumping power. A numerical study was done to validate the program by test running it for the finless annuli for similar boundary conditions; the results obtained in the present work show the same trend as that of Kakac and Yucel

Association between unintended pregnancy and maternal antenatal care services use in Ethiopia: analysis of Ethiopian demographic and health survey 2016

IntroductionUnintended pregnancy disproportionately affects women in low and middle-income countries including Ethiopia. Previous studies identified the magnitude and negative health outcomes of unintended pregnancy. However, studies that examined the relationship between antenatal care (ANC) utilization and unintended pregnancy are scarce.ObjectiveThis study aimed to examine the relationship between unintended pregnancy and ANC utilization in Ethiopia.MethodsThis is a cross-sectional study conducted using the fourth and most recent Ethiopian Demographic Health Survey (EDHS) data. The study comprised a weighted sample of 7,271 women with last alive birth and responded to questions on unintended pregnancy and ANC use. The association between unintended pregnancy and ANC uptake was determined using multilevel logistic regression models adjusted for possible confounders. Finally p < 5% was considered significant.ResultsUnintended pregnancy accounted for nearly a quarter of all pregnancies (26.5%). After adjusting for confounders, a 33% (AOR: 0.67; 95% CI, 0.57–0.79) lower odds of at least one ANC uptake and a 17% (AOR: 0.83; 95% CI, 0.70–0.99) lower odds of early ANC booking were found among women who had unintended pregnancy compared to women with intended pregnancy. However, this study founds no association (AOR: 0.88; 95% CI, 0.74, 1.04) between unintended pregnancy and four or more ANC visits.ConclusionOur study found that having unintended pregnancy was associated with a 17 and 33% reduction in early initiation and use of ANC services, respectively. Policies and programs designed to intervene against barriers to early initiation and use of ANC should consider unintended pregnancy

Effect of tranexamic acid on coagulation and fibrinolysis in women with postpartum haemorrhage (WOMAN-ETAC): protocol and statistical analysis plan for a randomized controlled trial.

Background: Postpartum haemorrhage (PPH) is a leading cause of maternal death. Tranexamic acid has the potential to reduce bleeding and a large randomized controlled trial of its effect on maternal health outcomes in women with PPH (The WOMAN trial) is ongoing. We will examine the effect of tranexamic acid on fibrinolysis and coagulation in a subset of WOMAN trial participants. Methods. Adult women with clinically diagnosed primary PPH after vaginal or caesarean delivery are eligible for inclusion in the WOMAN trial. In a sub-group of trial participants, blood samples will be collected at baseline and 30 minutes after the first dose of tranexamic acid or matching placebo.  Our primary objective is to evaluate the effect of tranexamic acid on fibrinolysis. Fibrinolysis will be assessed by measuring D-dimers and by rotational thromboelastometry (ROTEM). Secondary outcomes are international normalized ratio (INR), prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen, haemoglobin and platelets. We aim to include about 180 women from the University College Hospital, Ibadan in Nigeria. Discussion:  This sub-study of WOMAN trial participants should provide information on the mechanism of action of tranexamic acid in women with postpartum haemorrhage. We present the trial protocol and statistical analysis plan. The trial protocol was registered prior to the start of patient recruitment. The statistical analysis plan was completed before un-blinding. Trial registration: The trial was registered: ClinicalTrials.gov, Identifier NCT00872469 https://clinicaltrials.gov/ct2/show/NCT00872469; ISRCTN registry, Identifier ISRCTN76912190 http://www.isrctn.com/ISRCTN76912190 (Registration date: 22/03/2012)

Haematological and fibrinolytic status of Nigerian women with post-partum haemorrhage.

BACKGROUND: Early treatment with tranexamic acid reduces deaths due to bleeding after post-partum haemorrhage. We report the prevalence of haematological, coagulation and fibrinolytic abnormalities in Nigerian women with postpartum haemorrhage. METHODS: We performed a secondary analysis of the WOMAN trial to assess laboratory data and rotational thromboelastometry (ROTEM) parameters in 167 women with postpartum haemorrhage treated at University College Hospital, Ibadan, Nigeria. We defined hyper-fibrinolysis as EXTEM maximum lysis (ML) > 15% on ROTEM. We defined coagulopathy as EXTEM clot amplitude at 5 min (A5)  1.5. RESULTS: Among the study cohort, 53 (40%) women had severe anaemia (haemoglobin< 70 g/L) and 17 (13%) women had severe thrombocytopenia (platelet count < 50 × 109/L). Thirty-five women (23%) had ROTEM evidence of hyper-fibrinolysis. Based on prothrombin ratio criteria, 16 (12%) had coagulopathy. Based on EXTEM A5 criteria, 49 (34%) had coagulopathy. CONCLUSION: Our findings suggest that, based on a convenience sample of women from a large teaching hospital in Nigeria, hyper-fibrinolysis may commonly occur in postpartum haemorrhage. Further mechanistic studies are needed to examine hyper-fibrinolysis associated with postpartum haemorrhage. Findings from such studies may optimize treatment approaches for postpartum haemorrhage. TRIAL REGISTRATION: The Woman trial was registered: NCT00872469; ISRCTN76912190 (Registration date: 22/03/2012)

Effect of tranexamic acid on coagulation and fibrinolysis in women with postpartum haemorrhage (WOMAN-ETAC): a single-centre, randomised, double-blind, placebo-controlled trial

Background: Postpartum haemorrhage (PPH) is a leading cause of maternal death. The WOMAN trial showed that tranexamic acid (TXA) reduces death due to bleeding in women with PPH. We evaluated the effect of TXA on fibrinolysis and coagulation in a sample of WOMAN trial participants. Methods: : Adult women with a clinical diagnosis of PPH were randomised to receive 1 g TXA or matching placebo in the WOMAN trial. Participants in the WOMAN trial at University College Hospital (Ibadan, Nigeria) also had venous blood taken just before administration of the first dose of trial treatment and again 30 (±15) min after the first dose (the ETAC study).  We aimed to determine the effects of TXA on fibrinolysis (D-dimer and rotational thromboelastometry maximum clot lysis (ML)) and coagulation (international normalized ratio and clot amplitude at 5 min). We compared outcomes in women receiving TXA and placebo using linear regression, adjusting for baseline measurements. Results: : Women (n=167) were randomised to receive TXA (n=83) or matching placebo (n=84). Due to missing data, seven women were excluded from analysis. The mean (SD) D-dimer concentration was 7.1 (7.0) mg/l in TXA-treated women and 9.6 (8.6) mg/l in placebo-treated women (p=0.09). After adjusting for baseline, the D-dimer concentration was 2.16 mg/l lower in TXA-treated women (-2.16, 95% CI -4.31 to 0.00, p=0.05). There was no significant difference in ML between TXA- and placebo-treated women (12.3% (18.4) and 10.7% (12.6), respectively; p=0.52) and no significant difference after adjusting for baseline ML (1.02, 95% CI -3.72 to 5.77, p=0.67).  There were no significant effects of TXA on any other parameters. Conclusion: TXA treatment was associated with reduced D-dimer levels but had no apparent effects on thromboelastometry parameters or coagulation tests. Registration: ISRCTN76912190 (initially registered 10/12/2008, WOMAN-ETAC included on 22/03/2012) and NCT00872469 (initially registered 31/03/2009, WOMAN-ETAC included on 22/03/2012)