Transcription factors TgbHLH95 and TgbZIP44 cotarget terpene biosynthesis gene TgGPPS in Torreya grandis nuts.

Terpenes are volatile compounds responsible for aroma and the postharvest quality of commercially important xiangfei (Torreya grandis) nuts, and there is interest in understanding the regulation of their biosynthesis. Here, a transcriptomics analysis of xiangfei nuts after harvest identified 156 genes associated with the terpenoid metabolic pathway. A geranyl diphosphate (GPP) synthase (TgGPPS) involved in production of the monoterpene precursor GPP was targeted for functional characterization, and its transcript levels positively correlated with terpene levels. Furthermore, transient overexpression of TgGPPS in tobacco (Nicotiana tabacum) leaves or tomato (Solanum lycopersicum) fruit led to monoterpene accumulation. Analysis of differentially expressed transcription factors identified one basic helix-loop-helix protein (TgbHLH95) and one basic leucine zipper protein (TgbZIP44) as potential TgGPPS regulators. TgbHLH95 showed significant transactivation of the TgGPPS promoter, and its transient overexpression in tobacco leaves led to monoterpene accumulation, whereas TgbZIP44 directly bound to an ACGT-containing element in the TgGPPS promoter, as determined by yeast 1-hybrid test and electrophoretic mobility shift assay. Bimolecular fluorescence complementation, firefly luciferase complementation imaging, co-immunoprecipitation, and GST pull-down assays confirmed a direct protein-protein interaction between TgbHLH95 and TgbZIP44 in vivo and in vitro, and in combination these proteins induced the TgGPPS promoter up to 4.7-fold in transactivation assays. These results indicate that a TgbHLH95/TgbZIP44 complex activates the TgGPPS promoter and upregulates terpene biosynthesis in xiangfei nuts after harvest, thereby contributing to its aroma.

Modelling seasonal household variation in harvested rainwater availability: a case study in Siaya County, Kenya.

Rainwater harvesting reliability, the proportion of days annually when rainwater demand is fully met, is challenging to estimate from cross-sectional household surveys that underpin international monitoring. This study investigated the use of a modelling approach that integrates household surveys with gridded precipitation data to evaluate rainwater harvesting reliability, using two local-scale household surveys in rural Siaya County, Kenya as an illustrative case study. We interviewed 234 households, administering a standard questionnaire that also identified the source of household stored drinking water. Logistic mixed effects models estimated stored rainwater availability from household and climatological variables, with random effects accounting for unobserved heterogeneity. Household rainwater availability was significantly associated with seasonality, storage capacity, and access to alternative improved water sources. Most households (95.1%) that consumed rainwater faced insufficient supply of rainwater available for potable needs throughout the year, with intermittencies during the short rains for most households with alternative improved sources. Although not significant, stored rainwater lasts longer for households whose only improved water source was rainwater (301.8 ± 40.2 days) compared to those having multiple improved sources (144.4 ± 63.7 days). Such modelling analysis could enable rainwater harvesting reliability estimation, and thereby national/international monitoring and targeted follow-up fieldwork to support rainwater harvesting.

The modulation effect of auxiliary ligands on photochromic properties of 3D naphthalene diimide coordination polymers.

Two novel naphthalene diimide (NDI) coordination polymers (CPs), [Cd(NicNDI)(4,4'-SBC)] (1) and [Cd(NicNDI)(2,2'-BPC)] (2) (NicNDI = (3-pyridylacylamino)-1,4,5,8-naphthalene diimide, 4,4'-SBC = 4,4'-stilbene dicarboxylic acid, 2,2'-BPC = 2,2'-biphenyl dicarboxylic acid), were designed and prepared by the combination of electron-deficient NicNDI and electron-rich aromatic carboxylic acid ligands in the presence of cadmium ions. The usage of aromatic carboxylic acid ligands with different conjugation degrees, sizes, shapes and charge densities leads to the generation of distinct interpenetrated three-dimensional (3D) frameworks. Interestingly, photochromism of 1 and weak photoactivity of 2 should be attributed to the introduction of different auxiliary ligands and consequently the formation of distinct interfacial contacts of electron donors (EDs)/electron acceptors (EAs) (dπ-π = 3.427 Å, infinite -ED-EA-ED-EA- for 1vs. dπ-π = 3.634 Å, discrete ED-EA-ED for 2), suggesting a subtle modulating effect of auxiliary ligands on interfacial contacts, photoinduced intermolecular electron transfer (PIET) and photoresponsive behaviors.

A spatiotemporal analysis of cattle herd movement in relation to drinking-water sources: implications for Cryptosporidium control in rural Kenya.

Given the increasing evidence that domestic contact with livestock is a risk factor for child diarrhoea in low- and middle-income countries, there have been calls for greater quantification of human-livestock contact in such countries. This study aimed to quantify seasonality in cattle proximity to domestic water sources and household compounds and develop a preliminary landscape model of faecal deposition by cattle. A total of 120 cattle in smallholder herds in the Asembo area of Siaya County, Kenya, were tracked over 1 week in April 2018 to July 2018 and November 2018 to February 2019 using GPS tracking devices. Dung deposition and behaviour were observed among 33 cattle from these herds over 185.4 hours. Mean cattle home ranges were small at 3.78 km2 and 5.85 km2 in the wet and dry seasons, respectively. There were significant differences between seasons in home range size, distance travelled from the household, and time spent tethered, but not in the time spent at domestic water sources or home range overlap with other herds. On average, 0.76 dung deposition events/hour were observed, with higher frequency in bulls. Variation in cattle proximity to household compounds and water sources did not account for seasonal variation in child diarrhoea in this population. The preliminary landscape model of faecal deposition by cattle could be further developed to inform interventions for safe separation of livestock and people, such as fencing and separate water troughs.

A mixed methods study to evaluate participatory mapping for rural water safety planning in western Kenya.

Water safety planning is an approach to ensure safe drinking-water access through comprehensive risk assessment and water supply management from catchment to consumer. However, its uptake remains low in rural areas. Participatory mapping, the process of map creation for resource management by local communities, has yet to be used for rural water safety planning. In this mixed methods study, to evaluate the validity of participatory mapping outputs for rural water safety planning and assess community understanding of water safety, 140 community members in Siaya County, Kenya, attended ten village-level participatory mapping sessions. They mapped drinking-water sources, ranked their safety and mapped potential contamination hazards. Findings were triangulated against a questionnaire survey of 234 households, conducted in parallel. In contrast to source type ranking for international monitoring, workshop participants ranked rainwater's safety above piped water and identified source types such as broken pipes not explicitly recorded in water source typologies often used for formal monitoring. Participatory mapping also highlighted the overlap between livestock grazing areas and household water sources. These findings were corroborated by the household survey and subsequent participatory meetings. However, comparison with household survey data suggested participatory mapping outputs omitted some water sources and landscape-scale contamination hazards, such as open defecation areas or flood-prone areas. In follow-up visits, participant groups ranked remediation of rainwater harvesting systems as the most acceptable intervention to address hazards. We conclude that participatory mapping can complement other established approaches to rural water safety planning by capturing informally managed source use and facilitating community engagement.

Variation in SARS-CoV-2 outbreaks across sub-Saharan Africa.

A surprising feature of the SARS-CoV-2 pandemic to date is the low burdens reported in sub-Saharan Africa (SSA) countries relative to other global regions. Potential explanations (for example, warmer environments1, younger populations2-4) have yet to be framed within a comprehensive analysis. We synthesized factors hypothesized to drive the pace and burden of this pandemic in SSA during the period from 25 February to 20 December 2020, encompassing demographic, comorbidity, climatic, healthcare capacity, intervention efforts and human mobility dimensions. Large diversity in the probable drivers indicates a need for caution in interpreting analyses that aggregate data across low- and middle-income settings. Our simulation shows that climatic variation between SSA population centers has little effect on early outbreak trajectories; however, heterogeneity in connectivity, although rarely considered, is likely an important contributor to variance in the pace of viral spread across SSA. Our synthesis points to the potential benefits of context-specific adaptation of surveillance systems during the ongoing pandemic. In particular, characterizing patterns of severity over age will be a priority in settings with high comorbidity burdens and poor access to care. Understanding the spatial extent of outbreaks warrants emphasis in settings where low connectivity could drive prolonged, asynchronous outbreaks resulting in extended stress to health systems.

Effect of Inter-Observer Variation on the Association between Contamination Hazards and the Microbiological Quality of Water Sources: A Longitudinal Study.

Sanitary risk inspection protocols are often used to identify contamination hazards at water sources; however, different observers sometimes struggle to record hazards consistently. This study aimed to assess the effect of inter-observer variation in hazard observations on the strength of relationships between observed hazards and the bacterial contamination of water sources, particularly relationships with animal-related hazards. In a longitudinal study, five surveyors independently recorded hazards at 93 water sources used by 234 households in Siaya County, Kenya, in both wet and dry seasons. One surveyor collected samples from sources for subsequent Escherichia coli and intestinal enterococci testing. The relationship between each surveyor's hazard observations and high bacterial contamination was examined using logistic regression. After controlling for water source type and preceding rainfall; percentage scores for animal-related hazards were significantly related to high contamination with enterococci and E. coli for one surveyor (odds ratio 1.02; 95% confidence intervals 1.00-1.03 for both parameters), but not for the remaining four surveyors. The relationship between observed contamination hazards and the microbiological contamination of water sources is sensitive to variation in hazard recording between surveyors. Sanitary risk protocols should be designed to enable robust and consistent observation of hazards.

Effect of Temperature and Humidity on Oil Quality of Harvested Torreya grandis cv. Merrillii Nuts During the After-Ripening Stage.

Temperature and relative humidity (RH) influence post-harvest ripening, a crucial stage for quality promotion in some oil plants or fruits. Torreya grandis cv. Merrillii nuts, which are rich in unsaturated fatty acids (UFA), are easily affected by temperature and humidity, and they oxidize quickly during the post-harvest ripening stage, leading to the deterioration of nut quality. In this study, the main nutraceutical components, fatty acid composition, and related metabolic parameters of lipid rancidity under four treatments (20°C and 70% RH, T20-LH; 30°C and 70% RH, T30-LH; 20°C and 90% RH, T20-HH; 30°C and 90% RH, T30-HH) were measured. The post-harvest ripening process was advanced under HH treatments (T20-HH and T30-HH) compared to LH treatments (T20-LH and T30-LH) and was associated with a shorter time for the seed coat to turn dark black and a faster reduction in starch content. The amount of unsaturated fatty acids significantly increased under the T20-HH treatment, but significantly decreased under the T30-HH treatment from 12 to 16 d of ripening time. The acid value (AV) and lipase activity under the T30-HH treatment remained virtually constant from 12 to 16 d of ripening time, and this was accompanied by a dramatic increase in peroxide value (POV), lipoxygenase (LOX) activity, and relative expression of the LOX2 gene. Meanwhile, a significant positive correlation between LOX activity and POV, malondialdehyde (MDA) content, and O2⋅- content was observed. The results imply that the lower amount of oxidative rancidity induced by the T20-HH treatment is related to the LOX activity induced by down-regulation of the LOX2 gene during the late after-ripening stage. Therefore, the T20-HH treatment not only promoted the post-harvest process of T. grandis 'Merrillii' nuts but also delayed lipid oxidation, which was ultimately associated with better oil quality at the late after-ripening stage.

An Assessment of Inter-Observer Agreement in Water Source Classification and Sanitary Risk Observations.

Sanitary risk inspection, an observation protocol for identifying contamination hazards around water sources, is promoted for managing rural water supply safety. However, it is unclear how far different observers consistently identify contamination hazards and consistently classify water source types using standard typologies. This study aimed to quantify inter-observer agreement in hazard identification and classification of rural water sources. Six observers separately visited 146 domestic water sources in Siaya County, Kenya, in wet and dry seasons. Each observer independently classified the source type and conducted a sanitary risk inspection using a standard protocol. Water source types assigned by an experienced observer were cross-tabulated against those of his colleagues, as were contamination hazards identified, and inter-observer agreement measures calculated. Agreement between hazards observed by the most experienced observer versus his colleagues was significant but low (intra-class correlation = 0.49), with inexperienced observers detecting fewer hazards. Inter-observer agreement in classifying water sources was strong (Cohen's kappa = 0.84). However, some source types were frequently misclassified, such as sources adapted to cope with water insecurity (e.g. tanks drawing on both piped and rainwater). Observers with limited training and experience thus struggle to consistently identify hazards using existing protocols, suggesting observation protocols require revision and their implementation should be supported by comprehensive training. Findings also indicate that field survey teams struggle to differentiate some water source types based on a standard water source classification, particularly sources adapted to cope with water insecurity. These findings demonstrate uncertainties underpinning international monitoring and analyses of safe water access via household surveys.

A longitudinal study of the association between domestic contact with livestock and contamination of household point-of-use stored drinking water in rural Siaya County (Kenya).

BACKGROUND: Emerging evidence suggests close domestic proximity of livestock and humans may lead to microbiological contamination of hands, objects, food and water supplies within domestic environments, adversely impacting public health. However, evidence quantifying the relationship between livestock, domestic animals, humans and microbiological contamination of household stored water remains limited. AIM: This longitudinal study aimed to examine the relationship between domestic contact with livestock and domestic animals on microbiological contamination of household Point-of-Use (POU) stored drinking water in rural Kenya and assess the influence of choice of faecal indicator on such associations. METHODOLOGY: A survey was performed in 234 households in Siaya county, Kenya, to observe presence of livestock (cattle, goats, poultry) and domestic animals (cats, dogs) in household compounds, alongside other risk factors for contamination of POU stored drinking water such as sanitation, storage conditions and hygiene practices. Samples from water sources (e.g. piped, spring/wells, boreholes, surface and rainwater) and from POU storage containers were tested for E. coli and intestinal enterococci. Livestock-related risk factors for water contamination were examined through multinomial regression, controlling for confounders. RESULTS: Rainwater was the main POU water source and was found to be highly susceptible to contamination. Multivariate analysis showed greater risk of gross (>100 CFU/100 mL) water contamination (with E. coli) for households where goats were observed, and/or where poultry roosted in proximity to stored household water (relative risk RR = 2.71; p = 0.001 and RR = 2.02; p = 0.012 respectively). Presence of a poultry coop was also associated with elevated intestinal enterococci densities (RR = 4.46; p = 0.001). Associations between contamination and livestock risk factors were thus similar for both bacteria groups, but E. coli counts declined more rapidly following collection from surface waters than enterococci counts (p = 0.024). CONCLUSION: The presence of livestock (particularly goats) and poultry within household compounds increases POU water contamination risk, suggesting the need for improved interventions to address cross-contamination within rural domestic settings. Within Siaya county, more effective community education is needed to raise awareness of POU water quality protection, particularly of rainwater.

High variation expected in the pace and burden of SARS-CoV-2 outbreaks across sub-Saharan Africa.

A surprising feature of the SARS-CoV-2 pandemic to date is the low burdens reported in sub-Saharan Africa (SSA) countries relative to other global regions. Potential explanations (e.g., warmer environments1, younger populations2-4) have yet to be framed within a comprehensive analysis accounting for factors that may offset the effects of climate and demography. Here, we synthesize factors hypothesized to shape the pace of this pandemic and its burden as it moves across SSA, encompassing demographic, comorbidity, climatic, healthcare and intervention capacity, and human mobility dimensions of risk. We find large scale diversity in probable drivers, such that outcomes are likely to be highly variable among SSA countries. While simulation shows that extensive climatic variation among SSA population centers has little effect on early outbreak trajectories, heterogeneity in connectivity is likely to play a large role in shaping the pace of viral spread. The prolonged, asynchronous outbreaks expected in weakly connected settings may result in extended stress to health systems. In addition, the observed variability in comorbidities and access to care will likely modulate the severity of infection: We show that even small shifts in the infection fatality ratio towards younger ages, which are likely in high risk settings, can eliminate the protective effect of younger populations. We highlight countries with elevated risk of 'slow pace', high burden outbreaks. Empirical data on the spatial extent of outbreaks within SSA countries, their patterns in severity over age, and the relationship between epidemic pace and health system disruptions are urgently needed to guide efforts to mitigate the high burden scenarios explored here.

The Kinase Activity of Drosophila BubR1 Is Required for Insulin Signaling-Dependent Stem Cell Maintenance.

As a core component of the mitotic checkpoint complex, BubR1 has a modular organization of molecular functions, with KEN box and other motifs at the N terminus inhibiting the anaphase-promoting complex/cyclosome, and a kinase domain at the C terminus, whose function remains unsettled, especially at organismal levels. We generate knock-in BubR1 mutations in the Drosophila genome to separately disrupt the KEN box and the kinase domain. All of the mutants are homozygously viable and fertile and show no defects in mitotic progression. The mutants without kinase activity have an increased lifespan and phenotypic changes associated with attenuated insulin signaling, including reduced InR on the cell membrane, weakened PI3K and AKT activity, and elevated expression of dFoxO targets. The BubR1 kinase-dead mutants have a reduced cap cell number in female germaria, which can be rescued by expressing a constitutively active InR. We conclude that one major physiological role of BubR1 kinase in Drosophila is to modulate insulin signaling.

Mapping access to domestic water supplies from incomplete data in developing countries: An illustrative assessment for Kenya.

Water point mapping databases, generated through surveys of water sources such as wells and boreholes, are now available in many low and middle income countries, but often suffer from incomplete coverage. To address the partial coverage in such databases and gain insights into spatial patterns of water resource use, this study investigated the use of a maximum entropy (MaxEnt) approach to predict the geospatial distribution of drinking-water sources, using two types of unimproved sources in Kenya as illustration. Geographic locations of unprotected dug wells and surface water sources derived from the Water Point Data Exchange (WPDx) database were used as inputs to the MaxEnt model alongside geological/hydrogeological and socio-economic covariates. Predictive performance of the MaxEnt models was high (all > 0.9) based on Area Under the Receiver Operator Curve (AUC), and the predicted spatial distribution of water point was broadly consistent with household use of these unimproved drinking-water sources reported in household survey and census data. In developing countries where geospatial datasets concerning drinking-water sources often have necessarily limited resolution or incomplete spatial coverage, the modelled surface can provide an initial indication of the geography of unimproved drinking-water sources to target unserved populations and assess water source vulnerability to contamination and hazards.

Integration of population census and water point mapping data-A case study of Cambodia, Liberia and Tanzania.

Sustainable Development Goal (SDG) 6 has expanded the Millennium Development Goals' focus from improved drinking-water to safely managed water services. This expanded focus to include issues such as water quality requires richer monitoring data and potentially integration of datasets from different sources. Relevant data sets include water point mapping (WPM), the survey of boreholes, wells and other water points, census and household survey data. This study examined inconsistencies between population census and WPM datasets for Cambodia, Liberia and Tanzania, and identified potential barriers to integrating the two datasets to meet monitoring needs. Literatures on numbers of people served per water point were used to convert WPM data to population served by water source type per area and compared with census reports. For Cambodia and Tanzania, discrepancies with census data suggested incomplete WPM coverage. In Liberia, where the data sets were consistent, WPM-derived data on functionality, quantity and quality of drinking water were further combined with census area statistics to generate an enhanced drinking-water access measure for protected wells and springs. The process revealed barriers to integrating census and WPM data, including exclusion of water points not used for drinking by households, matching of census and WPM source types; temporal mismatches between data sources; data quality issues such as missing or implausible data values, and underlying assumptions about population served by different water point technologies. However, integration of these two data sets could be used to identify and rectify gaps in WPM coverage. If WPM databases become more complete and the above barriers are addressed, it could also be used to develop more realistic measures of household drinking-water access for monitoring.

A Global Perspective on Drinking-Water and Sanitation Classification: An Evaluation of Census Content.

Following the recent expiry of the United Nations' 2015 Millennium Development Goals (MDGs), new international development agenda covering 2030 water, sanitation and hygiene (WASH) targets have been proposed, which imply new demands on data sources for monitoring relevant progress. This study evaluates drinking-water and sanitation classification systems from national census questionnaire content, based upon the most recent international policy changes, to examine national population census's ability to capture drinking-water and sanitation availability, safety, accessibility, and sustainability. In total, 247 censuses from 83 low income and lower-middle income countries were assessed using a scoring system, intended to assess harmonised water supply and sanitation classification systems for each census relative to the typology needed to monitor the proposed post-2015 indicators of WASH targets. The results signal a lack of international harmonisation and standardisation in census categorisation systems, especially concerning safety, accessibility, and sustainability of services in current census content. This suggests further refinements and harmonisation of future census content may be necessary to reflect ambitions for post-2015 monitoring.

A cross-sectional ecological study of spatial scale and geographic inequality in access to drinking-water and sanitation.

INTRODUCTION: Measuring inequality in access to safe drinking-water and sanitation is proposed as a component of international monitoring following the expiry of the Millennium Development Goals. This study aims to evaluate the utility of census data in measuring geographic inequality in access to drinking-water and sanitation. METHODS: Spatially referenced census data were acquired for Colombia, South Africa, Egypt, and Uganda, whilst non-spatially referenced census data were acquired for Kenya. Four variants of the dissimilarity index were used to estimate geographic inequality in access to both services using large and small area units in each country through a cross-sectional, ecological study. RESULTS: Inequality was greatest for piped water in South Africa in 2001 (based on 53 areas (N) with a median population (MP) of 657,015; D = 0.5599) and lowest for access to an improved water source in Uganda in 2008 (N = 56; MP = 419,399; D = 0.2801). For sanitation, inequality was greatest for those lacking any facility in Kenya in 2009 (N = 158; MP = 216,992; D = 0.6981), and lowest for access to an improved facility in Uganda in 2002 (N = 56; MP = 341,954; D = 0.3403). Although dissimilarity index values were greater for smaller areal units, when study countries were ranked in terms of inequality, these ranks remained unaffected by the choice of large or small areal units. International comparability was limited due to definitional and temporal differences between censuses. CONCLUSIONS: This five-country study suggests that patterns of inequality for broad regional units do often reflect inequality in service access at a more local scale. This implies household surveys designed to estimate province-level service coverage can provide valuable insights into geographic inequality at lower levels. In comparison with household surveys, censuses facilitate inequality assessment at different spatial scales, but pose challenges in harmonising water and sanitation typologies across countries.