Significant Temporal Trends Research Articles

Temporal Greenness Trends in Stable Natural Land Cover and Relationships with Climatic Variability across the Conterminous United States

Abstract Assessment of temporal trends in vegetation greenness and related influences aids understanding of recent changes in terrestrial ecosystems and feedbacks from weather, climate, and environment. We analyzed 1-km normalized difference vegetation index (NDVI) time series data (1989–2016) derived from the Advanced Very High Resolution Radiometer (AVHRR) and developed growing-season time-integrated NDVI (GS-TIN) for estimating seasonal vegetation activity across stable natural land cover in the conterminous United States (CONUS). After removing areas from analysis that had experienced land-cover conversion or modification, we conducted a monotonic trend analysis on the GS-TIN time series and found that significant positive temporal trends occurred over 35% of the area, whereas significant negative trends were observed over only 3.5%. Positive trends were prevalent in the forested lands of the eastern one-third of CONUS and far northwest, as well as in grasslands in the north-central plains. We observed negative and nonsignificant trends mainly in the shrublands and grasslands across the northwest, southwest, and west-central plains. To understand the relationship of climate variability with these temporal trends, we conducted partial and multiple correlation analyses on GS-TIN, growing-season temperature, and water-year precipitation time series. The GS-TIN trends in northern forests were positively correlated with temperature. The GS-TIN trends in the central and western shrublands and grasslands were negatively correlated with temperature and positively correlated with precipitation. Our results revealed spatial patterns in vegetation greenness trends for different stable natural vegetation types across CONUS, enhancing understanding gained from prior studies that were based on coarser 8-km AVHRR data. Significance Statement Assessing vegetation trends, cycles, and related influences is important for understanding the responses and feedbacks of terrestrial ecosystems to climatic and environmental changes. We analyzed vegetation greenness trends (1989–2016) for stable natural land cover across the conterminous United States, based on vegetation index time series derived from coarse-resolution optical satellite sensors. We found greening trends in the forests of the east and far northwest and the grasslands of the northern central plains that correlated with increasing temperature in the regions. We observed browning and no trends mainly in the shrublands and grasslands across the northwest, southwest, and western central plains, associated with increasing temperature and decreasing precipitation. Future research should focus on vegetation greenness analysis using finer-resolution satellite data.

A new scoring system for operational indicators guiding leprosy monitoring and surveillance in Brazil

Objective: We aimed to develop a new score to facilitate and enhance the quantitative assessment of operational standard indicators guiding leprosy monitoring and surveillance, based on data from Brazilian hyperendemic regions, 2004-2019. Methods: We analyzed epidemiological and operational standard indicators of leprosy control from the database of the Notifiable Diseases Information System in Brazil’s North and Northeast regions. The so-called IntegraHans Operational Score (IHOS) was generated, integrating 10 indicators, with a final semi-quantitative score varying from 0 (worst scenario) to 1 (best scenario). We then applied the IHOS within an ecological and population-based study to assess temporal and spatial leprosy distributions from 2004 to 2019. Results: In total, 343,888 new leprosy cases were analyzed (61% of cases in the country). There was a significant temporal trend of the IHOS annual percentage change [-0.3; 95% confidence interval (CI): -0.5 to 0.0] during 2010-2019, with large cities showing a worsening trend (average annual percentage change -0.8, 95%CI: -1.1 to -0.4). After 2010, municipalities with low and medium social vulnerability, and those with medium human development and medium and high social prosperity, showed improved IHOS scores. Spatial patterns with the best IHOS scenarios were observed in the states of Rondônia, Tocantins, and Pernambuco. Conclusion: The IHOS combines different operational parameters and is an effective and simple tool to assess leprosy control programs in Brazil. The worst IHOS scores over time were identified in critical areas, such as large cities in hyperendemic areas and municipalities with lower endemicity.

The incidence of and risk factors for hospitalized acute kidney injury among people living with HIV on antiretroviral treatment.

The epidemiology of hospitalized acute kidney injury (AKI) among people living with HIV (PLWH) in the era of modern antiretroviral therapy (ART) for all PLWH is not well characterized. We evaluated the incidence of and risk factors for hospitalized AKI from 2005 to 2015 among PLWH on ART. We conducted a retrospective analysis of PLWH from the Johns Hopkins HIV Clinical Cohort. We defined hospitalized AKI as a rise of ≥0.3mg/dL in serum creatinine (SCr) within any 48-h period or a 50% increase in SCr from baseline and assessed associations of risk factors with incident AKI using multivariate Cox regression models. Most participants (75%) were black, 34% were female, and the mean age was 43years. The incidence of AKI fluctuated annually, peaking at 40 per 1000 person-years (PY) [95% confidence interval (CI) 22-69 per 1000 PY] in 2007, and reached a nadir of 20 per 1000 PY (95% CI 11-34 per 1000 PY) in 2010. There was no significant temporal trend (-3.3% change per year; 95% CI -8.6 to 2.3%; P=0.24). After multivariable adjustment, characteristics independently associated with AKI included black race [hazard ratio (HR) 2.44; 95% CI 1.42-4.20], hypertension (HR 1.62; 95% CI 1.09-2.38), dipstick proteinuria >1 (HR 1.86; 95% CI 1.07-3.23), a history of AIDS (HR 1.82; 95% CI 1.29-2.56), CD4 count <200 cells/µL (HR 1.46; 95% CI 1.02-2.07), and lower serum albumin (HR 1.73 per 1g/dL decrease; 95% CI 1.02-2.07). In this contemporary cohort of PLWH, the annual incidence of first AKI fluctuated during the study period. Attention to modifiable AKI risk factors and social determinants of health may further reduce AKI incidence among PLWH.

89. Positive Blood Culture Trends and Variability among U.S. Hospitals, 2012-2017

Abstract Background Although studies have shown blood culture rates have remained stable in recent years, understanding the variability in positivity over time and among hospitals may inform diagnostic and antimicrobial stewardship efforts. Methods We included all discharges from hospitals participating in the Premier Healthcare Database and Cerner Health Facts from 2012-2017 in months where a hospital reported at least one blood culture with antimicrobial susceptibility results. A blood culture episode was defined as one or more cultures drawn within 1 hour. Episodes on or before day 3 were defined as admission episodes (AE), and those drawn on day 4 or later were defined as post-admission episodes (PAE). Culture episodes yielding any organism were categorized as pathogen+ (i.e., at least 1 non-commensal organism identified) or commensal (i.e., only commensal organisms identified). Positive or commensal episode rates were calculated as the percentage of pathogen+ or commensal episodes among all blood culture episodes for AE and PAE. Logistic regression with generalized estimating equation models accounting for hospital-level clustering were used to measure time trends and facility level associations. Results Among 19.6 million discharges in 493 hospitals, 7.5 million blood culture episodes were identified; 336,102 (4.5%) were pathogen+, and 110,236 (1.5%) were commensals. The rate of pathogen+ AEs increased from 4.2% to 4.7% over the study period (p&amp;lt; .0001) and there was no significant temporal trend in the rate of pathogen+ PAEs (p=.7956) (Figure 1). AE commensals decreased significantly in 2016-2017 compared to previous years (1.6% in 2012 to 1.3% in 2017; p=.0092), and PAE commensals decreased significantly over the study period from 2.0% to 1.2% (p&amp;lt; .0001) (Figure 1). We observed substantial inter-hospital variability for each outcome (Figure 2). In addition, differences among hospital characteristics and seasonality were noted for AE and PAE pathogen+ rates and AE commensal rates (Figure 3), but not urbanicity or teaching hospital status. Monthly Positivity Rate of Blood Culture Episodes, Premier Healthcare Database and Cerner Health Facts, 2012-2017 Adjusted Odds Ratios and 95% Confidence Intervals of Blood Culture Episode Positive (Non-Commensal) and Commensal Rates and Associated Characteristics Conclusion While an increase AE pathogen+ rates and decrease in commensal rates could indicate improved culture ordering and collection practices, significant seasonal, regional, and facility-level variability calls for further investigation. Disclosures John A. Jernigan, MD, MS, Nothing to disclose

Social determinants and spatio-temporal variation of Ischemic Heart Disease in Manitoba

IntroductionThe aim was to study any spatial and/or temporal patterns of ischemic heart disease (IHD) prevalence and measure the effects of selected social determinants on these spatial and space-time patterns.MethodsData were obtained from the Population Research Data Repository housed at the Manitoba Centre for Health Policy to identify persons who were diagnosed with IHD between 1995 and 2018. These persons were geocoded to 96 geographic regions of Manitoba. An area-level socioeconomic factor index (SEFI-2) and the proportion of the population who was Indigenous were calculated for each geographic region using the 2016 Canadian Census data. Associations between these factors and IHD prevalence were measured using Bayesian spatial Poisson regression models. Temporal trends and spatio-temporal trends were measured using Bayesian spatio-temporal Poisson regression models.ResultsUnivariable models showed a significant association with increased regional Indigenous population proportion associated with a higher prevalence of IHD (RR: 0.07, 95% CredInt: (0.05, 0.10)) and for SEFI-2 (RR: 0.17, 95% CredInt: (0.11, 0.23)). Using a multivariable model, after accounting for the proportion of the population that was Indigenous, there was no evidence of an association between IHD prevalence and area-level socioeconomic factor. Spatio-temporal models showed no significant overall temporal trend in IHD prevalence, but there were significant spatially varying temporal trends within the 96 regions.ConclusionsAssociation between Indigenous population proportion and IHD is consistent with previous research. No significant overall temporal trend was measured. However, regions with significantly increasing trends and significantly decreasing trends in IHD prevalence were identified.

Analysis of canine cardiovascular therapeutic agent prescriptions using electronic health records in primary care veterinary practices in the United Kingdom

Introduction/objectivesCanine cardiovascular (CV) diseases are often managed in primary care settings. The objectives were to describe CV therapeutic agent (CVTA) prescribing patterns in primary care practices in the United Kingdom (UK) and to evaluate recorded clinical signs, diagnostic tests and justifications for use of torasemide, a recently marketed and authorised loop-diuretic in the UK. Animals, materials and methodsElectronic health records (EHRs) describing 3,579,420 consultations (1,043,042 unique dogs) were collated (1 April 2014 and 31 December 2018) by the Small Animal Veterinary Surveillance Network from 270 veterinary practices. Consultations prescribing at least one CVTA were identified. Annual variation in individual CVTA prescriptions was analysed using mixed-effects binomial regression models. Free-text clinical narratives were manually read to determine the first-prescribing event for torasemide. ResultsTwenty-nine thousand and seven consultations (0.81% of all consultations, 95% confidence interval [CI], 0.76–0.86) prescribed CVTA in 14,148 (1.36%) dogs. Furosemide (52.8% of CV-prescribing consultations, 95% CI 50.7–54.9) and pimobendan (51.9%, 95% CI 50.1–53.7) were most prescribed. Longitudinal analysis (2014–2018) showed a significant negative temporal trend for angiotensin-converting enzyme inhibitors (p < 0.001), and furosemide (p = 0.003) and a positive temporal trend for pimobendan (p = 0.020) and torasemide (p < 0.001). First prescriptions of torasemide were identified in 16.5% of torasemide-prescribing consultations. Where justification for prescription of torasemide was identified (32.5%), furosemide resistance was the most common (92.0%). ConclusionsEHRs can be used to temporally monitor prescribing habits, including responses to market authorisations. Despite authorisation in the UK for torasemide use as a first-line diuretic, it was most commonly prescribed after furosemide resistance.

Effects of hydrologic variability and remedial actions on first flush and metal loading from streams draining the Silverton caldera, 1992–2014

AbstractThis study examined water quality in the upper Animas River watershed, a mined watershed that gained notoriety following the 2015 Gold King mine release of acid mine drainage to downstream communities. Water‐quality data were used to evaluate trends in metal concentrations and loads over a two‐decade period. Selected sites included three sites on tributary streams and one main‐stem site on the Animas River downstream from the tributary confluences. During the study period, metal concentrations and loads varied seasonally and annually because of hydrologic variability and remedial actions designed to ameliorate the effects of acid mine drainage. Water‐quality data were divided into two periods based on the timing of remedial activities in the watershed. The first period includes active water treatment, surface reclamation and installation of bulkheads in adits; the second period includes the decade following these activities. Water‐quality data were used to estimate annual and monthly zinc loads using the Adjusted Maximum Likelihood Method (using LOADEST software) and U.S. Geological Survey streamflow data. This study presents one of the first applications of LOADEST focused on metal loads. Monthly flow‐weighted concentrations were analysed using a Mann‐Kendall trend test to determine the direction, magnitude, and significance of temporal trends in zinc loading in any given month and using t‐test comparisons between the two periods. Zinc loads estimated for the Animas River below the tributaries indicate decreased zinc loading during the rising limb of the hydrograph in the second period, perhaps reflecting a reduction of snowmelt‐derived zinc load following surface reclamation activities. In contrast, base‐flow zinc loading increased at the main‐stem site, perhaps because of the cessation of water treatment in tributary streams. Flow weighting of monthly load estimates yielded increased statistical significance and enabled more nuanced differentiation between the effects of hydrologic variability and remedial activities on zinc loading.

Heterogeneous timing of freshwater input into Kobbefjord, a low‐arctic fjord in Greenland

AbstractThe majority of freshwater input from Greenland to the global ocean stems from the Greenland Ice Sheet. Currently, almost a quarter of the freshwater flowing from Greenland is derived from catchments that are disconnected from the Greenland Ice Sheet. Despite their importance to the total freshwater flux and influence on fjord geochemistry, there is relatively little monitoring data available for those catchments and therefore the drivers of regional differences in export are largely unknown. We present a dataset of 12 years of discharge of four catchments less than 15 km apart, that are different in size (between 7 and 32 km2), local glacier coverage (4%–11%) and lake cover (0%–5%). They all drain into Kobbefjord, a well‐studied fjord in West Greenland, near Greenland's capital Nuuk. Between catchments, the magnitude of discharge varies at annual, seasonal and sub‐daily timescales, due to differences in physical catchment properties as well as local climate variability. We find that annual specific discharges vary greatly (between 1.2 and 1.9 m/year on a 12‐year average) due to a longitudinal precipitation gradient from West to East caused by different amount of orographic precipitation shading. The seasonal cycle of discharge (amplitude, timing and minimum flow) differs among the sites mainly due to different exposure to solar radiation as a driver for major snowmelt; the small ice coverage in the catchments plays only a minor role in discharge variability. Dry years generally increase the relative differences in annual specific discharge and no significant temporal trends have been found in the studied catchments. On a sub‐daily timescale, the difference in timing of maximum discharge during fair‐weather days (&gt;80% maximum solar radiation and no precipitation) ranged between 7 and 12 h, which is attributed to differences between the presence and elevation of lakes among the catchments. The response of discharge to major precipitation events is discussed, where a delay of between 5 and 7 h is found for the catchments that do not contain lakes near the gauge.

Survival improvement and prognosis for hepatocellular carcinoma: analysis of the SEER database

BackgroundHepatocellular carcinoma (HCC) incidences have been increasing in the United States. This study aimed to examine temporal trend of HCC survival and determine prognostic factors influencing HCC survival within the U.S. population.MethodsThe Surveillance Epidemiology, and End Results (SEER) database was used to identify patients diagnosed with primary HCC from 1988 to 2015. Overall survival (OS) and disease-specific survival (DSS) were calculated by the Kaplan-Meier method. Univariate and multivariate Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for prognostic factors and comparing survival between patients diagnosed at different periods (per 5-year interval).ResultsA total of 80,347 patients were included. The proportions of both young patients (< 45 years) and old patients (≥75 years) decreased over time (P < 0.001) and the male-to-female ratio increased over time (P < 0.001). Significant decreasing temporal trends were observed for HCC severity at diagnosis, including SEER stage, tumor size, tumor extent, and lymph node involvement (P < 0.001 for all). OS and DSS of patients with HCC improved over time (P < 0.001). After adjusting for patient and tumor characteristics and treatment difference, period of diagnosis retained an independent factor for improved DSS and its prognostic significance was evident for localized and regional HCC (P < 0.001), but not for distant HCC. On multivariate analyses, young age, female gender, Hispanic ethnicity, and married status were predictors favoring DSS, whereas a worse DSS was observed for patients with tumor > 5 cm, with vascular invasion, and with lymph node involvement. Patients treated with liver-directed therapy (HR = 0.54, 95% CI: 0.35–0.56), hepatic resection (HR = 0.35, 95% CI: 0.33–0.37), and transplantation (HR = 0.14, 95% CI: 0.13–0.15) had significantly longer DSS compared with those who received no surgery. In stratified analyses, the beneficial effects of surgical approach, regardless therapy type, were significant across all stages.ConclusionsOur results indicate a significant improvement in survival for HCC patients from 1988 to 2015, which may be attributable to advances in early diagnosis and therapeutic approaches.

Multi-Species Feeding Association Dynamics Driven by a Large Generalist Predator

Multi-species feeding associations (MSFAs) are temporary communities of animals exploiting the same or co-occurrent resources. Their dynamics are species dependent, often creating competitive interactions, but they can also increase foraging efficiency and ultimately individual fitness. The foraging behaviors of some species can enhance prey capture by others, with different roles depending on the species present. Here, we use the Hauraki Gulf, New Zealand, as a model system to quantitatively characterize the principal types of MSFAs between 2011 and 2020. We determine the foraging associations of a large generalist predator, the Bryde’s whale, and how shifts in its prey preference change the dynamics between seabird competitors. Hierarchical clustering from influential predator groups identified three types of MSFAs. Two of mainly fish-feeding predators, one including and one lacking Bryde’s whales, and one involving (although not limited to) plankton-feeders associated with Bryde’s whales. Cluster frequencies featured significant temporal trends, whereas MSFA diversity and whale association rate showed no significant changes. Bryde’s whales’ increasing reliance on zooplankton highlights their foraging plasticity, with changes in cluster frequencies and resource competition related to this shift from fish to zooplankton. The role of Bryde’s whales varies from joiners and terminators in fish-feeding aggregations to initiators with plankton-feeding seabird associations, thereby changing the MSFA dynamics. MSFAs tend toward a diversity equilibrium, i.e., a maximum number of species involved before competitive effects exceed the benefits of interaction. Functional MSFAs where heterospecific interactions are important to foraging success can be affected by changing composition. Future work should focus on the behavioral interactions between key predators, prey availability and their effect on MSFAs.

Temporal change and the influence of climate and weather factors on mercury concentrations in Hudson Bay polar bears, caribou, and seabird eggs

Temporal trends of mercury in Arctic wildlife are inconsistent within and between species and are often insignificant, which limits data interpretation. Recent multivariate analyses have shown that weather and climate factors (e.g. temperatures, sea ice conditions) are related to total Hg (THg) concentrations in wildlife tissues, though relatively few studies have explored these relationships. The present study compared time series of THg concentrations in liver of polar bear (Ursus maritimus, 2007/08–2015/16), eggs of thick-billed murres (Uria lomvia, 1993–2015) and kidney of caribou (Rangifer tarandus groenlandicus, 2006–2015) from the Hudson Bay region of Canada and statistically modelled THg over time with available climate and weather data. Significant temporal trends of THg concentrations were not detected in any species. However, in multivariate models that included time-lagged sea ice freeze up dates, THg concentrations increased 4.4% yr−1 in Qamanirjuaq caribou. Sea ice conditions were also related to THg levels in polar bear liver but not those in eggs of murres, though year was not a signifcant factor. Greater precipitation levels one to two years prior to sampling were associated with greater THg concentrations in polar bears and caribou, likely due to greater deposition, flooding and discharge from nearby wetlands and rivers. Time-lagged Arctic and/or North Atlantic Oscillation (AO/NAO) indices also generated significant, inverse models for all three species, agreeing with relationships in other time series of similar length. The magnitude and direction of many relationships were affected by season, duration of time-lags, and the length of the time series. Our findings support recent observations suggesting that temporal studies monitoring Hg in Arctic wildlife should consider including key climatic or weather factors to help identify consistent variables of influence and to improve temporal analyses of THg time series.

Metabolic Disrupting Effects of Polychlorinated Biphenyls Revealed by Long-Term Temporal Variations of Lipids in Detritivorous Fish from the Rio de la Plata Basin.

The long-term covariation (2002-2017) of lipids, polychlorinated biphenyls (PCBs), and sewage tracers was studied in the detritivorous fish (Prochilodus lineatus) and settling detritus from the Rio de la Plata. Fatty fish from polluted Buenos Aires area (BA) exhibited a significant decrease of muscle lipids (71 ± 12 to 29 ± 8.6% dry weight; p < 0.0001), triglycerides (94 to 85%, p < 0.001), and 18 carbon fatty acids (18C-FA: 59 ± 4.8 to 48 ± 1.4%; p < 0.01), reflecting a reduction of lipid accumulation, largely triglycerides enriched in 18C-FA, with a concomitant ∼20-times decline of PCBs (∼20 to >1 μg g-1 dw). The 2017 individuals of the BA series converged with leaner and more pristine northern fish (N), which showed no significant temporal variation (20 ± 10% lipids, 67 ± 8.7% triglycerides, 41 ± 8.1% 18C-FA, and 0.22 ± 0.42 μg g-1 dw PCB). In contrast, the fecal sterol tracer coprostanol remained abnormally higher in BA fish muscle with no significant temporal trend (120 ± 102 vs 6.6 ± 10 μg g-1 dw or 4.4 ± 2.8 vs 0.63 ± 1.2% sterols at N). The same pattern was observed in BA settling detritus, i.e., a temporal decrease of PCBs with high, stable coprostanol concentrations denoting sustained sewage inputs, while northern detritus was enriched in plant sterols. This long-term covariation of lipids and PCBs in fish muscle from polluted BA converging with more pristine and homogeneous northern specimens while maintaining a sewage-derived diet provides rare field evidence of the declining effect of PCBs controlling the temporal variation of muscular lipids in fish.

Seasonal and Interannual changes in abundance and community structure of tintinnids in the Levantine Sea in relation to hydrographic conditions from 2002 to 2014

Extensive information on the short period of tintinnid community structure along the Mediterranean coastline is available. Contrarily, time-series data are scarce. In the framework of a monitoring program, the distribution, abundance and community structure of tintinnid assemblages were investigated at monthly intervals over a thirteen year period (2002–2014) in two stations (B1 neritic and B2 oceanic) located in the northern Lebanese marine waters. Results revealed a significant temporal trend over the whole series for salinity in both stations and density and species richness at B2. A significant difference was only detected in the salinity between the two sites. The seasonal variations of tintinnid abundance showed different trends between the stations. Abundances peaked in November 27.14 (14 to 52.8) ind.l−1, January 27 (14 to 56) ind.l−1 and May 24 (7 to 35.8) ind.l−1 at B1 and in December 20 (18 to 25) ind.l−1 and May 19 (11.5 to 33) ind.l−1 at B2, while the lowest was in July 6 (4.2 to 12) ind.l−1 and August 6.6 (3.4 to 20.6) ind.l−1 at B1 and B2, respectively. The leading species at the studied sites were Tintinnopsis beroidea, Dadayiella ganymedes, Eutintinnus lusus-undae, Steenosemella steenstrupii, Codonellopsis schabi, and Rhabdonella spiralis. The period of highest species richness generally corresponded to periods of high overall tintinnid abundance and showed analogous patterns at both stations with a maximum occurring in January 12.1 (11 to 16) at B1 and March 11.7 (10 to 13) at B2. Tintinnid abundance showed high peaks in 2003 and 2007 in both stations but peaked differently for the other years.

APPLICATION OF PRINCIPAL COMPONENT ANALYSIS TO DROUGHT INDICATORS OF THREE REPRESENTATIVE CROATIAN REGIONS

Drought has become a very frequent hydrological event globally, including in Croatia. It can generally be explained by air temperature and precipitation changes on an annual and seasonal basis, owing to climate change. To contribute to the knowledge on drought phenomena in Croatia, the changes in air temperature and precipitation over a relatively long period between 1951 and 2018 were analyzed. The meteorological stations included in the research were Osijek, Zagreb, and Split, which represented the climate of the entire country. Drought was estimated using the standardized precipitation evapotranspiration index, which is one of the most comprehensive drought indices. Furthermore, the drought severity and duration were calculated using run theory. These parameters were tested for homogeneity using the standard normal homogeneity test. Only the air temperature exhibited inhomogeneity, with a break year in 1991 (Zagreb and Split) and 1998 (Osijek). The existence of significant temporal trends was tested using the non-parametric Mann–Kendall trend test. The probability of drought occurrence with a certain duration and severity was calculated using the copula function. Finally, principal component analysis was applied to the computed standardized Mann–Kendall test statistic (ZMK ) to define the relevance of each parameter change and their combination in drought occurrence on a seasonal basis. Drought occurrence was less recognizable from 1951 to 1991 (1998). In the second sub-period, the impact of an increasing air temperature was the most significant variable, particularly in Zagreb.

Spatial Variability and Temporal Trends of Climate Change in Southwest Ethiopia: Association with Farmers’ Perception and Their Adaptation Strategies

The impact of climate change is a global threat, and its effect is more pronounced in developing countries. It is vital to link physical data analysis with endogenous knowledge and practices of farmers to strengthen their adaptive capacity. This study was conducted to explore spatial variability and temporal trends of temperature and rainfall in association with farmers’ perceptions and their adaptation strategies in Southwest Ethiopia. Daily rainfall and temperature data of twelve weather stations were collected from the National Meteorological Agency of Ethiopia for the period 1983 to 2016. Farmers’ perceptions about climate change and its impact and their adaptation strategies were assessed through a survey. Spatial variability and temporal trends of rainfall and temperature were analyzed using ArcGIS and R software. Sen’s slope estimator and Mann–Kendall’s trend tests were used to detect the magnitude and statistical significance of changes in rainfall and temperature. Spatial analysis of rainfall showed high variability over the region. There were no consistent and significant temporal trends of annual and seasonal rainfall of the area. Significant and upward trends of annual maximum and minimum temperatures were reported for all stations. Accordingly, annual maximum and minimum temperatures were increased by 0.71 and 0.65°C, respectively, over the period 1983 to 2016. Farmers had a good awareness of climate change and its impact. Adaptation strategies used by farmers included soil and water conservation practices (66.21%), crop diversification (62.16%), modifying planting date (42.56%), agroforestry practices (35.13%), use of drought-tolerant variety (33.95%), use of early maturing crop (27.03%), and livelihood diversification (25.42%). As most of these adaptation strategies were familiarized by a small number of farmers, further effort is needed to identify factors limiting the adoption of these strategies. Furthermore, additional planned strategies and supports that widen available options at the farmers’ disposal should be introduced to strengthen their adaptive capacity.

Effects of Lactic Acid Bacteria on Microbial Metabolic Functions of Paper Mulberry Silage: A BIOLOG ECO Microplates Approach.

Lactic acid bacteria occupy an important position in silage microorganisms, and the effects of exogenous lactic acid bacteria on silage quality have been widely studied. Microbial metabolism has been proved as an indicator of substrate utilization by microorganisms. Paper mulberry is rich in free carbohydrate, amino acids, and other components, with the potential to be decomposed and utilized. In this study, changes in the microbial metabolism characteristics of paper mulberry silage with Lactiplantibacillus plantarum (LP) and Lentilactobacillus buchneri (LB) were studied along with a control (CK) using BIOLOG ECO microplates. The results showed that average well-color development (AWCD), Shannon diversity, Shannon evenness, and Simpson diversity exhibited significant temporal trends. LB and LP responded differently in the early ensiling phase, and the AWCD of LB was higher than LP at 7 days. Principal component analysis revealed that CK, LB, and LP samples initially clustered at 3 days and then moved into another similar cluster after 15 days. Overall, the microplates methodology applied in this study offers important advantages, not least in terms of accuracy.

Patient characteristics and cardiac surgical outcomes at a tertiary care hospital in Kenya, 2008-2017: a retrospective study.

BackgroundCardiac surgeries are high risk procedures that require specialized care and access to these procedures is often limited in resource-poor countries. Although fatalities for surgical patients across Africa are twice that of the global rate, cardiac surgical mortality continent-wide is only slightly higher than all-surgical mortality. Understanding demographic and health characteristics of patients and the associations of these characteristics with morbidity and mortality events is important in guiding care decisions. Therefore, the objectives of this study were to: (a) describe the characteristics of cardiac surgical patients; (b) identify the associations between these characteristics and morbidity and mortality events following cardiac surgery.MethodsPatient characteristics and post-surgical complications were abstracted for all cardiac surgical patients treated at a tertiary care hospital in Kenya from 2008 to 2017. Descriptive analyses of demographic factors, co-morbidities, peri-operative conditions, and post-surgical complications were conducted for adult and pediatric patients. Cochran-Armitage trend test was used to assess temporal trends in risk of death. Multivariable ordinary logistic and Firth logistic models were used to investigate predictors of surgical outcomes.ResultsThe study included a total of 181 patients (150 adult and 31 pediatric patients). Most (91.3%) adult patients had acquired conditions while 45.2% of the pediatric patients had congenital defects. Adult patients tended to have co-morbid conditions including hypertension (16.7%), diabetes mellitus (7.3%), and nephropathy (6.7%). Most patients (76.0% adults and 96.8% pediatric patients) underwent ≤ 2 surgical procedures during their hospital stay. Seventy percent of adult and 54.8% of the pediatric patients experienced at least one post-surgical complication including mediastinal hemorrhage, acute kidney injury and death. Patient characteristics played the greatest roles in predicting post-surgical complications. For adult patients, significant predictors of acute kidney injury included atrial fibrillation (OR = 18.25; p = .001), mitral valve replacement (OR = 0.14; p = .019), and use of cardiopulmonary bypass (OR = 0.06; p = .002). Significant predictors of 30-day mortality were age (OR = 1.05; p = .015) and atrial fibrillation (OR = 4.12, p = .018). Although the number of surgeries increased over the decade-long study period, there were no significant (p = .467) temporal trends in the risk of death.ConclusionsAwareness of demographic and peri-surgical factors that are predictors of complications is useful in guiding clinical decisions to reduce morbidity and mortality. Identification of co-morbidities as the most useful predictors of post-surgical complications suggests that patient characteristics may be a larger contributor to the incidence of complications than surgical practices.

The temporal development of plant-soil feedback is contingent on competition and nutrient availability contexts.

Strength and direction of plant-soil feedback (PSF), the reciprocal interactions between plants and soil, can change over time and have distinct effects on different life stages. PSF and its temporal development can also be modified by external biotic and abiotic factors such as competition and resource availability, yet most PSF research is conducted in simple experimental settings without considering temporal changes. Here I have studied the effect of different competitive settings (intraspecific, interspecific, and no competition) and nutrient addition on the magnitude and direction of biomass-based PSF (performance in conspecific relative to heterospecific inoculum) across 46 grassland species, estimated at the 4th, 10th, and 13th month of the response phase. I also examined whether conspecific inoculum had a long-term effect on plant survival at the 36th month, and whether biomass-based PSF may predict survival-based PSF effects. PSF pooled across all treatments and time points was negative, but a significant overall temporal trend or differences among competitive settings were missing. PSF developed unimodally for interspecific competition across the three time points, whereas it declined gradually in case of intraspecific and no competition. Nutrient addition attenuated negative biomass-based PSF and eliminated negative effects of conspecific inoculum on survival. Interspecific differences in biomass-based PSF were related to survival-based PSF, but only after nutrient addition. This study demonstrates that PSF is dynamic and modulated by external abiotic and biotic factors. PSF research should consider the temporal dynamics of focal communities to properly estimate how PSF contributes to community changes, preferably directly in the field.

Aerosol characteristics from earth observation systems: A comprehensive investigation over South Asia (2000–2019)

The present study summarizes two decades (2000–2019) of climatology and trends in aerosol loading and optical properties using a high spatial resolution data obtained from NASA's MODIS MAIAC and MISR aerosol products supplemented by moderate resolution aerosol data from OMI sensor over South Asia (SA). MISR AOD showed good agreement against AERONET AOD with 68.68% of the retrievals falling within the expected error and high Pearson's correlation coefficient (R = 0.83). The 20 years geometric mean of MAIAC and MISR AOD revealed higher loading of aerosols over the Indo-Gangetic Plain (IGP) and Eastern coast of India by 30% to 44% compared to the mean AOD over the entire SA. The highest mean AOD under cloud-free conditions was noted during monsoon season, followed by pre-monsoon, post-monsoon, and winter. The high contribution of coarse-mode AOD (cAOD) mainly from natural aerosol emission and small-mode AOD (sAOD) from local anthropogenic emissions are the main driver to high AOD in monsoon and pre-monsoon seasons. Besides, the presence of high humidity during the monsoon season favors the hygroscopic growth of the particles and leads to higher AOD values over SA. The high spatial resolutions of MODIS/MAIAC and MISR aerosol products enabled the identification of previously unobserved aerosol hotspots over Bihar, West Bengal, and the eastern Indian coastal state of Odisha, which is mainly dominated by small aerosol particles. The contributions of smaller aerosol particles to the total aerosol loading were found to be higher during post-monsoon and winter over most states in India, Nepal, and Bangladesh. In contrast, the contribution of coarser particles was higher over Pakistan during pre-monsoon and monsoon seasons. Smaller particles were predominantly retrieved over the Indian states dominated by mining industries, including Jharkhand and Odisha. A typical dominance of absorbing carbonaceous aerosols was also noted over the northwestern region of IGP during post-monsoon, which otherwise was mainly affected by mixed dust aerosols and carbonaceous aerosols in pre-monsoon and monsoon seasons. A statistically significant positive temporal trend in AOD was observed for the whole study period, over most of the SA region, which was influenced by the increase in small particles over India and Bangladesh. Urban/industrial weakly absorbing aerosols were found to be the main contributor to a similarly positive trend over Central India and East coast Indian states. Overall, recent advancements in high spatial resolution satellite-based aerosol optical properties showed good potential to identify the aerosol hotspots and constrain aerosol types across a highly polluted SA region.

Benthic invertebrate assemblages and leaf‐litter breakdown along the eucrenal–hypocrenal ecotone of a rheocrene spring in Central Italy: Are there spatial and seasonal differences?

AbstractTo better understand the pattern of variation in biocomplexity of springs and first‐order streams, it is essential to explore how the characteristics of spring communities may vary from the spring source (eucrenal) to the first reach of the originating springbrook (hypocrenal). For these reasons, we assessed spatial and temporal variation of crenic assemblages and leaf‐litter breakdown along a 45‐m reach of a spring–springbrook system in Central Italy. We found that physicochemical and hydrological parameters of Vera Spring did not vary significantly along the 45‐m reach investigated. In contrast, total richness of assemblages was significantly higher at 20 and 45 m from the spring source, while abundances were more variable and did not show significant differences between seasons and among sites. The composition of assemblages did not show significant temporal trends in all sites investigated, while spatial differences along the eucrenal–hypocrenal ecotone were more prominent. The functional organization of assemblages was relatively stable in both space and time, and no spatial differences were observed in the rate of leaf‐litter breakdown, though the dry mass loss of poplar leaves was slightly higher at the most downstream site. We conclude that immediately after groundwater emergence, spring communities are less stable and more variable while they tend to be better organized at short distance downstream. Small and gradual spatial changes in the strength of competitive interactions and predation pressures may have a fundamental role in structuring spring communities more than variation in abiotic parameters and/or differences in quantity and quality of food resources.