Checking Normality and Homoscedasticity in the General Linear Model Using Diagnostic Plots

The microclimatic effects of the native shrub Ephedra californica (Mormon tea) in California drylands

Introduction

The impacts of climate change can be profound in many ecosystems worldwide, including drylands such as arid and semi-arid scrublands and grasslands. Foundation plants such as shrubs can provide microclimatic refuges for a variety of taxa. These shrubs can directly influence micro6 environmental measures, and indirectly increase the local environmental heterogeneity as a result. We examined the hypothesis that, in comparison to an open gap, foundation shrubs improve the microclimate beneath their canopy and that microclimate is in turn a significant predictor of annual vegetation. The following predictions were made: 1) mean air temperature (NSAT), ground temperature (SGT), and vapour pressure deficit (VPD) will be significantly lower under the shrubs than in the open microsites; 2) shrub canopy size predicts microclimate; 3) site-level aridity estimates and percent shrub cover influence annual plant abundance and richness; and 4) the site13 level mean of NSAT and VPD predict annual plant abundance and richness.

Methods

Our study took place in Southwestern California, U.S.A. We used a handheld device with a probe to measure microclimatic variables such as near-surface air temperature (NSAT), near-surface relative humidity (NSRH), and surface ground temperature (SGT) at the shrub species Ephedra californica and in the open gap, across six sites in California, United States. Air temperature and RH were then used to calculate VPD. The mean number of vascular plant species across each site was also recorded.

Results & discussion

Only SGT was significantly reduced under shrub canopies. Canopy volume was not a significant predictor of all three microclimatic variables, demonstrating that even small, low-stature shrubs can have facilitative effects. Furthermore, total shrub cover and aridity at sites significantly predicted mean plant richness and abundance. There were significantly more plants associated with shrubs and there were significantly more species associated with the open. Mean air temperature and VPD at the site-level significantly predicted vegetation abundance and richness, though microsite-level differences were only significant for richness. Foundation shrubs are a focal point of resiliency in dryland ecosystems. Understanding their impact on microclimate can inform us of better management, conservation, and restoration frameworks.

Associations of Systematic Inflammatory Markers with Diet Quality, Blood Pressure, and Obesity in the AIRWAVE Health Monitoring Study

Introduction

Chronic low-grade inflammation is a characteristic feature of obesity, and elevated levels of inflammation are associated with pathophysiologic consequences and a constellation of metabolic disturbances, such as hypertension. The relationships of inflammation with diet, obesity, and hypertension are complex, hence, this study aimed to assess cross-sectional relationships between inflammatory scores, diet quality, obesity, high blood pressure (BP), and hypertension in the Airwave Health Monitoring Study cohort, a large cohort of police officers and police staff in the United Kingdom.

Methods

Data from 5198 men and 3347 women who completed health screening measurements and dietary assessment between 2007 and 2012 were included (n=8545 adults). Platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and the systemic immune-inflammation index (SII) were calculated. Diet quality was evaluated using the Nutrient-Rich Food 9.3 (NRF9.3) index score.

Results

Results show that a 1SD higher diet quality score, waist circumference, and systolic/diastolic BP were significantly associated with SII differences of -33.3 (95% confidence interval (CI): -49.0, -17.6), 8.2 (95% CI: 0.2, 16.6), 17.9 (95% CI: 10.1, 25.8), and 18.3 (95% CI: 10.8, 25.7) (Model 2; P<0.0001), respectively. A 1SD higher diet quality score, waist circumference, and BMI were also significantly associated with PLR (P<0.0001). The odds of elevated PLR were higher in those with higher systolic and diastolic BP (P<0.0001, P=0.0006, respectively).

Conclusion

In conclusion, the findings of this analysis add to the existing knowledge indicating a link between inflammation and conditions such as obesity, hypertension, and behavioral factors including diet quality. Of the various inflammatory scores evaluated, SII and PLR were consistently significantly associated with diet quality and these conditions.

Down syndrome: orofacial pain, masticatory muscle hypotonia, and sleep disorders

The aim of the present study was to investigate orofacial pain in individuals with Down syndrome (DS) and determine possible associations with masticatory muscle hypotonia (MMH), maximum mouth opening (MMO), and sleep disorders. Twenty-three individuals with DS underwent a standardized clinical examination using Axis I of the Diagnostic Criteria for Temporomandibular Disorders, for the diagnosis of pain in the masseter and temporal muscles and temporomandibular joint (TMJ). MMH was investigated using electromyography of the temporal and masseter muscles and the measurement of maximum bite force (MBF). MMO was measured using an analog caliper. Sleep disorders (obstructive sleep apnea [OSA], snoring index [SI], and sleep bruxism index [SBI]) were investigated using type II polysomnography. Statistical analysis was performed. Nonsignificant differences were found in muscle and TMJ pain between the sexes. However, myalgia and referred myofascial pain in the left masseter muscle were more frequent in males (69%) than females (40%). Electrical activity of the temporal (left: p = .002; right: p = .004) and masseter (left: p = .008) muscles was significantly lower in males than in females. MBF range was lower in males than females, indicating the highest MMH among males. OSA, SI, and SBI were identified in both sexes, but with no statistically significant differences. We concluded that myalgia and referred myofascial pain were found in some individuals with DS, especially in males. Arthralgia was found mainly in females. Temporal and masseter myalgia may have exerted an influence on the severity of MMH in males, particularly on the left side.

Arbovirus risk perception as a predictor of mosquito-bite preventive behaviors in Ponce, Puerto Rico

Mosquito-borne arboviruses are an important cause of morbidity and mortality in the Caribbean. In Puerto Rico, chikungunya, dengue, and Zika viruses have each caused large outbreaks during 2010-2022. To date, the majority of control measures to prevent these diseases focus on mosquito control and many require community participation. In 2018, the U.S. Centers for Disease Control and Prevention launched the COPA project, a community-based cohort study in Ponce, Puerto Rico, to measure the impact of novel vector control interventions in reducing arboviral infections. Randomly selected households from 38 designated cluster areas were offered participation, and baseline data were collected from 2,353 households between May 2018 and May 2019. Household-level responses were provided by one representative per home. Cross-sectional analyses of baseline data were conducted to estimate 1) the association between arboviral risk perception and annual household expenditure on mosquito control, and 2) the association between arboviral risk perception and engagement in ≥3 household-level risk reduction behaviors. In this study, 27% of household representatives believed their household was at high risk of arboviruses and 36% of households engaged in at least three of the six household-level preventive behaviors. Households where the representative perceived their household at high risk spent an average of $35.9 (95% confidence interval: $23.7, $48.1) more annually on mosquito bite prevention compared to households where the representative perceived no risk. The probability of engaging in ≥3 household-level mosquito-preventive behaviors was 10.2 percentage points greater (7.2, 13.0) in households where the representatives perceived high risk compared to those in which the representatives perceived no risk. Paired with other research, these results support investment in community-based participatory approaches to mosquito control and providing accessible information for communities to accurately interpret their risk.

Resistant starch wheat increases PYY and decreases GIP but has no effect on self-reported perceptions of satiety

Dietary fiber has numerous health benefits, such as increasing satiety, and is regularly included in healthy dietary recommendations. However, different types and sources of fiber vary in their chemical properties and biological effects. This double-blind, randomized, placebo-controlled, crossover study investigated the effects of resistant starch type 2 (RS2) from wheat on self-reported perceptions of satiety and associated gut hormones in 30 healthy adults ages 40-65 years of age. Participants consumed rolls made using either RS2-enriched wheat flour or a wild-type flour for one week before a test day during which they ate a mixed meal containing the same roll type. Both self-reported perceptions of satiety and plasma concentrations of gut hormones were measured following the meal to assess whether the RS2-enriched wheat enhanced satiety and suppressed hunger for a longer period than the control wheat. Exploratory analysis indicated that fasting and peak concentration of peptide YY_3-36 (PYY_3-36; q_fast = 0.02, q_peak = 0.02) increased, while peak concentration and iAUC of glucose-dependent insulinotropic peptide (GIP; q_peak < 0.001, q_iAUC < 0.001) decreased after ingesting RS2-enriched wheat. However, self-reported perceptions of hunger or fullness using visual analog scales (VAS) did not differ following the test meal.

Stereopsis and Response Times between Collegiate Table Tennis Athletes and Non-Athletes

Table tennis athletes and non-athletes potentially differ in stereopsis and eye–hand response times (RT), but whether stereopsis correlates with response time has scarcely been discussed. We aimed to compare stereopsis and RT between collegiate table tennis athletes and non-athletes and to examine the correlation between stereopsis and RT. From December 2016 to October 2019, table tennis athletes (n = 80) and non-athletes (n = 56) were recruited. Stereopsis was measured in four modes (A25, A50, R25, R50: approaching and receding directions at 25 mm/s or 50 mm/s). RT was measured with simple and choice tasks at zero, shoulder, and random distance. For stereopsis, the judged deviations were smaller during the approaching phases. Men had smaller A25 than women (p =0.012), whereas table tennis athletes showed smaller R25 and A50 than non-athletes (p = 0.03, 0.01, respectively). RT increased from simple to choice conditions and from zero to random, followed by shoulder distance. Men were significantly faster than women in choice tasks (p < 0.01). Table tennis athletes performed better in RT than the non-athletes (p < 0.05). No correlation was observed between stereopsis and RT (r = −0.01 to 0.12). In conclusion, athletes from table tennis sports showed better stereopsis and RT than non-athletes. Men had better stereopsis and RT than women. There was no correlation between stereopsis and RT.

From the Andes to the desert: 16S rRNA metabarcoding characterization of aquatic bacterial communities in the Rimac river, the main source of water for Lima, Peru

The Rimac river is the main source of water for Lima, Peru's capital megacity. The river is constantly affected by different types of contamination including mine tailings in the Andes and urban sewage in the metropolitan area. In this work, we aim to produce the first characterization of aquatic bacterial communities in the Rimac river using a 16S rRNA metabarcoding approach which would be useful to identify bacterial diversity and potential understudied pathogens. We report a lower diversity in bacterial communities from the Lower Rimac (Metropolitan zone) in comparison to other sub-basins. Samples were generally grouped according to their geographical location. Bacterial classes Alphaproteobacteria, Bacteroidia, Campylobacteria, Fusobacteriia, and Gammaproteobacteria were the most frequent along the river. Arcobacter cryaerophilus (Campylobacteria) was the most frequent species in the Lower Rimac while Flavobacterium succinicans (Bacteroidia) and Hypnocyclicus (Fusobacteriia) were the most predominant in the Upper Rimac. Predicted metabolic functions in the microbiota include bacterial motility and quorum sensing. Additional metabolomic analyses showed the presence of some insecticides and herbicides in the Parac-Upper Rimac and Santa Eulalia-Parac sub-basins. The dominance in the Metropolitan area of Arcobacter cryaerophilus, an emergent pathogen associated with fecal contamination and antibiotic multiresistance, that is not usually reported in traditional microbiological quality assessments, highlights the necessity to apply next-generation sequencing tools to improve pathogen surveillance. We believe that our study will encourage the integration of omics sciences in Peru and its application on current environmental and public health issues.

Drivers of reef fish assemblages in an upwelling region from the Eastern Tropical Pacific Ocean

Reef fish assemblages are exposed to a wide range of anthropogenic threats as well as chronic natural disturbances. In upwelling regions, for example, there is a seasonal influx of cool nutrient-rich waters that may shape the structure and composition of reef fish assemblages. Given that climate change may disrupt the natural oceanographic processes by altering the frequency and strength of natural disturbances, understanding how fish assemblages respond to upwelling events is essential to effectively manage reef ecosystems under changing ocean conditions. This study used the baited remote underwater video stations (BRUVS) and the traditional underwater visual census (UVC) to investigate the spatiotemporal patterns of reef fish assemblages in an upwelling region in the North Pacific of Costa Rica. A total of 183 reef fish species from 60 families were recorded, of which 166 species were detected using BRUVS and 122 using UVC. Only 66% of all species were detected using both methods. This study showed that the upwelling had an important role in shaping reef fish assemblages in this region, but there was also a significant interaction between upwelling and location. In addition, other drivers such as habitat complexity and habitat composition had an effect on reef fish abundances and species. To authors' knowledge, this is the first study in the Eastern Tropical Pacific that combines BRUVS and UVC to monitor reef fish assemblages in an upwelling region, which provides more detailed information to assess the state of reef ecosystems in response to multiple threats and changing ocean conditions.

Ammonium Transformation in 14 Lakes along a Trophic Gradient

Ammonia is a widespread pollutant in aquatic ecosystems originating directly and indirectly from human activities, which can strongly affect the structure and functioning of the aquatic foodweb. The biological oxidation of NH4+ to nitrite, and then nitrate is a key part of the complex nitrogen cycle and a fundamental process in aquatic environments, having a profound influence on ecosystem stability and functionality. Environmental studies have shown that our current knowledge of physical and chemical factors that control this process and the abundance and function of involved microorganisms are not entirely understood. In this paper, the efficiency and the transformation velocity of ammonium into oxidised compounds in 14 south-alpine lakes in northern Italy, with a similar origin, but different trophic levels, are compared with lab-scale experimentations (20 °C, dark, oxygen saturation) that are performed in artificial microcosms (4 L). The water samples were collected in different months to highlight the possible effect of seasonality on the development of the ammonium oxidation process. In four-liter microcosms, concentrations were increased by 1 mg/L NH4+ and the process of ammonium oxidation was constantly monitored. The time elapsed for the decrease of 25% and 95% of the initial ion ammonium concentration and the rate for that ammonium oxidation were evaluated. Principal Component Analysis and General Linear Model, performed on 56 observations and several chemical and physical parameters, highlighted the important roles of total phosphorus and nitrogen concentrations on the commencement of the oxidation process. Meanwhile, the natural concentration of ammonium influenced the rate of nitrification (µg NH4+/L day). Seasonality did not seem to significantly affect the ammonium transformation. The results highlight the different vulnerabilities of lakes with different trophic statuses.