Contextual violence and its link to social aggression: a study of community violence in Juárez
The city of Juárez, Mexico has been immersed in an atmosphere of violence and danger for more than a decade. Due to this violence, residents of Juárez may be at risk of severe contextual victimization, which occurs when individuals are indirectly affected by the physical and socio-cultural conditions of their violent communities through second-hand information (e.g., witnessing or hearing about violent acts in their everyday life). The objective of this study was to explore the effects of contextual victimization on variables related to community violence such as aggression, post-traumatic stress disorder (PTSD), and acceptance of violence. Data were collected from a sample of university students in Juárez (n = 298) using the Aggression Questionnaire (AQ), the Acceptance of Violence Scale (AVS), Checklist for PTSD Traits scale, and the Contextual Victimization by Community Violence scale (CVCV). Participants’ responses were analyzed in structural equation models (SEM) to uncover the latent variables behind each scale and test the hypothesized effects of CVCV on PTSD, AQ and AVS. Good validity indexes and internal consistency of all instruments were confirmed. SEM show significant positive effects of contextual violence on PTSD and PTSD on the disposition to aggression, but not on the acceptance of violence. Also, the variance explained of PTSD and AQ found in the sample of women (20% of PTSD and 23% of AQ) is almost twice than in men’s sample (9% for PTSD and 14% for AQ).
© 2020 Martín del Campo-Ríos and Cruz-Torres
Martín del Campo-Ríos et al. (2020) Contextual violence and its link to social aggression: a study of community violence in Juárez. PeerJ 8:e9162 https://doi.org/10.7717/peerj.9162
Foliar application of abscisic acid mitigates cadmium stress and increases food safety of cadmium-sensitive lettuce (Lactuca sativa L.) genotype
Cadmium (Cd2 +) is among the toxic non-essential heavy metals that adversely affect plants metabolic processes and the safety of produce. However, plant hormones can improve plant’s tolerance to various stresses. This study investigated the effect of exogenous abscisic acid (ABA) on the biochemical and physiological processes and food safety of cadmium (Cd2 +)-sensitive lettuce genotype (Lüsu). Seedlings were subjected to five treatments: [(i) Control (untreated plants), (ii) 100 µM CdCl2, (iii) 100 µM CdCl2+10 µg L−1 ABA (iv) 10 µg L−1 ABA, and (v) 0.01 g L−1 ABA-inhibitor (fluridone)] for fourteen days in hydroponic system. The 100 µM CdCl2 increased the contents of hydrogen peroxide (H2O2) and malondialdehyde (MDA), decreased photosynthesis and plant biomass. Moreover, it decreased the contents of essential nutrients (except copper) in the leaves but increased the contents of toxic Cd2 + in the leaves and roots of the plants. Foliar application of fluridone (0.01 g L−1) also caused oxidative stress by increasing the contents of H2O2 and MDA. It also decreased the contents of nutrient elements in the leaves of the plants. However, exogenous ABA (10 µg L−1) mitigated the Cd2 +-induced stress, increased antioxidant enzymes activities, photosynthesis and plant biomass under CdCl2 treatment. Remarkably, exogenous ABA increased the contents of essential nutrient elements but decreased the Cd2 + content in leaves under the CdCl2 treatment. Our results have demonstrated that foliar application of ABA mitigates Cd2 + stress and increases the nutritional quality and food safety of Cd2 +-sensitive lettuce genotype under CdCl2 treatment.
Dawuda et al. (2020) Foliar application of abscisic acid mitigates cadmium stress and increases food safety of cadmium-sensitive lettuce (Lactuca sativa L.) genotype. PeerJ 8:e9270 https://doi.org/10.7717/peerj.9270
Association of retinal nerve fiber abnormalities with serum CNTF and cognitive functions in schizophrenia patients
Background Recent studies have reported reductions in retinal nerve fiber layers (RNFL) in schizophrenia. Ciliary neurotrophic factor (CNTF) has shown protective effects on both the neurogenesis and retina. This study aimed at investigating retinal abnormalities and establishing their correlation with serum CNTF and cognitive impairments in schizophrenic Chinese patients. Methods In total, 221 patients diagnosed with schizophrenia and 149 healthy controls were enrolled. Serum CNTF and clinical features of patients were investigated. Cognitive functions were evaluated with Repeatable Battery for the Assessment of Neuropsychology Status (RBANS). RNFL thickness and macular thickness (MT) of both eyes were measured with optical coherence tomography (OCT). T-tests and analysis of covariance were used to compare the variables between the patient and control groups, while multiple linear regression analysis was performed to determine the associations of RNFL thickness, CNTF and cognitive impairments. Results RNFL was found thinner in patients than in healthy controls (right: 88.18 ± 25.84 µm vs.102.13 ± 14.32 µm, p = 0.001; left: 92.84 ± 13.54 µm vs.103.71 ± 11.94 µm, p < 0.001). CNTF was lower in the schizophrenia group (1755.45 ± 375.73 pg/ml vs. 1909.99 ± 368.08 pg/ml, p = 0.001). Decline in RNFL thickness was found correlated with course of illness and serum CNTF in patients (all p < 0.05). Similarly, cognitive functions such as immediate memory and visuospatial functions were also found correlated with decline in RNFL thickness. Conclusion Decline in RNFL thickness was associated with cognitive impairments of schizophrenia and CNFT serum concentration. The possibility of reduction in RNFL thickness as a biomarker for schizophrenia needs to be further examined.
Liu et al. (2020) Association of retinal nerve fiber abnormalities with serum CNTF and cognitive functions in schizophrenia patients. PeerJ 8:e9279 https://doi.org/10.7717/peerj.9279
SSREnricher: a computational approach for large-scale identification of polymorphic microsatellites based on comparative transcriptome analysis
Microsatellite (SSR) markers are the most popular markers for genetic analyses and molecular selective breeding in plants and animals. However, the currently available methods to develop SSRs are relatively time-consuming and expensive. One of the most factors is low frequency of polymorphic SSRs. In this study, we developed a software, SSREnricher, which composes of six core analysis procedures, including SSR mining, sequence clustering, sequence modification, enrichment containing polymorphic SSR sequences, false-positive removal and results output and multiple sequence alignment. After running of transcriptome sequences on this software, a mass of polymorphic SSRs can be identified. The validation experiments showed almost all markers (>90%) that were identified by the SSREnricher as putative polymorphic markers were indeed polymorphic. The frequency of polymorphic SSRs identified by SSREnricher was significantly higher (P < 0.05) than that of traditional and HTS approaches. The software package is publicly accessible on GitHub (https://github.com/byemaxx/SSREnricher).
Luo et al. (2020) SSREnricher: a computational approach for large-scale identification of polymorphic microsatellites based on comparative transcriptome analysis. PeerJ 8:e9372 https://doi.org/10.7717/peerj.9372
Elephants in the neighborhood: patterns of crop-raiding by Asian elephants within a fragmented landscape of Eastern India
Loss of forest cover, rise in human populations and fragmentation of habitats leads to decline in biodiversity and extinction of large mammals globally. Elephants, being the largest of terrestrial mammals, symbolize global conservation programs and co-occur with humans within multiple-use landscapes of Asia and Africa. Within such shared landscapes, poaching, habitat loss and extent of human–elephant conflicts (HEC) affect survival and conservation of elephants. HEC are severe in South Asia with increasing attacks on humans, crop depredation and property damage. Such incidents reduce societal tolerance towards elephants and increase the risk of retaliation by local communities. We analyzed a 2-year dataset on crop depredation by Asian elephants (N = 380) events in North Bengal (eastern India). We also explored the effect of landscape, anthropogenic factors (area of forest, agriculture, distance to protected area, area of human settlements, riverine patches and human density) on the spatial occurrence of such incidents.Crop depredation showed a distinct nocturnal pattern (22.00–06:00) and majority of the incidents were recorded in the monsoon and post-monsoon seasons. Results of our spatial analysis suggest that crop depredation increased with an increase in the area of forest patches, agriculture, presence of riverine patches and human density. Probability of crop depredation further increased with decreasing distance from protected areas. Villages within 1.5 km of a forest patch were most affected. Crop raiding incidents suggest a deviation from the “high-risk high-gain male biased” foraging behavior and involved proportionately more mixed groups (57%) than lone bulls (43%). Demographic data suggest that mixed groups comprised an average of 23 individuals with adult and sub adult females, bulls and calves. Crop depredation and fatal elephant attacks on humans were spatially clustered with eastern, central and western parts of North Bengal identified as hotspots of HEC. Our results will help to prioritize mitigation measures such as prohibition of alcohol production within villages, improving condition of riverine patches, changing crop composition, fencing agriculture fields, implement early warning systems around protected areas and training local people on how to prevent conflicts.
Naha et al. (2020) Elephants in the neighborhood: patterns of crop-raiding by Asian elephants within a fragmented landscape of Eastern India. PeerJ 8:e9399 https://doi.org/10.7717/peerj.9399
TAPB and RSB protects cardiac diastolic function in elderly patients undergoing abdominopelvic surgery: a retrospective cohort study
Background Diastolic dysfunction, an early manifestation and clinical symptom of heart failure with preserved ejection fraction, can be influenced by various anesthesia management strategies. Trans-esophageal echocardiography was used to undertake to assess left ventricular diastolic function during anesthesia maintenance using sevoflurane alone and sevoflurane combining with transversus abdominis plane block and rectus sheath block in elderly patients with diastolic dysfunction undergoing abdominopelvic surgery. Methods Thirty-eight patients were divided into two groups in this retrospective study, sevoflurane and sevoflurane combining with TAPB and RSB according to employing different anesthesia maintenance schemes. The parameters HR, MAP, CVP, E, A, E/A, e, a, e/a, and E/a were obtained immediately after anesthesia induction hemodynamics stability (HR1, MAP1, CVP1, E1, A1, E1/A1, e1, a1, e1/a1, and E1/a1) and 1 hour later (HR2, MAP2, CVP2, E2, A2, E2/A2, e2, a2, e2/a2, and E2/a2). Results Transmitral diastolic Doppler flow characteristics illustrated E/A significant decreases in the S group but increases in the ST group (p = 0.02 < 0.05) 1 hour after anesthesia induction hemodynamic stability. Tissue Doppler imaging characteristics showed a more significant increase e/a (P = 0.005 < 0.05) and decreases in a value (p = 0.009 < 0.05) in the ST group 1 hour after anesthesia induction hemodynamics stability. Conclusions Maintaining anesthesia with sevoflurane combining with TAPB and RSB was more suitable for protecting cardiac diastolic function than sevoflurane alone in elderly patients with diastolic dysfunction undergoing open abdominal and pelvic surgery.
Gong et al. (2020) TAPB and RSB protects cardiac diastolic function in elderly patients undergoing abdominopelvic surgery: a retrospective cohort study. PeerJ 8:e9441 https://doi.org/10.7717/peerj.9441
Effects of vegetation restoration on soil quality in fragile karst ecosystems of southwest China
Soil quality assessment is important for karst ecosystems where soil erosion is significant. A large amount of vegetation restoration has been implemented since the early 21st century in degraded karst areas across southwestern China. However, the impacts on soil quality of different restoration types rarely have been compared systematically. In the current study, we investigated the soil quality after a number of vegetation restoration projects as well as their adjacent cropland by analyzing soil samples. Six vegetation restoration types were evaluated, including one natural restoration (natural shrubland, protected for 13 years), three economic forests (4 years Eucalyptus robusta, 4 years Prunus salicina and 6 years Zenia insignis) and two mixed forests (1 year Juglans regia–crop and 13 years Toona sinensis-Pennisetum purpureum ). We evaluated the benefits of different restoration types more accurately by setting each adjacent cropland as the control and setting the variation between the corresponding restored and control site as the evaluation object so that the background differences of six sites could be eliminated. The results indicated that natural shrubland, Toona sinensis-Pennisetum purpureum and Zenia insignis were effective in improving soil quality index (SQI) in degraded karst cropland largely due to their higher SOC and TN content. The variation of SQI (VSQI) of natural shrubland was significantly higher than that in Eucalyptus robusta, Prunus salicina and Juglans regia-crop in total soil layer (0–30 cm) (P < 0.05), indicating natural shrubland had better capacity to improve soil quality. The boosting regression tree model revealed that vegetation restoration type explained 73.49% and restoration time explained 10.30% of the variation in VSQI, which confirmed that vegetation restoration type and restoration time are critical for achieving soil reserves. Therefore, it is vital to select appropriate vegetation type in restoration projects and recovery for a long time in order to achieve better soil quality. The current study provides a theoretical basis on which to assess the effects of different vegetation restoration types on the heterogeneous degraded karst areas.
Guan et al. (2020) Effects of vegetation restoration on soil quality in fragile karst ecosystems of southwest China. PeerJ 8:e9456 https://doi.org/10.7717/peerj.9456
Effects of microbial evolution dominate those of experimental host-mediated indirect selection
Microbes ubiquitously inhabit animals and plants, often affecting their host’s phenotype. As a result, even in a constant genetic background, the host’s phenotype may evolve through indirect selection on the microbiome. ‘Microbiome engineering’ offers a promising novel approach for attaining desired host traits but has been attempted only a few times. Building on the known role of the microbiome on development in fruit flies, we attempted to evolve earlier-eclosing flies by selecting on microbes in the growth media. We carried out parallel evolution experiments in no- and high-sugar diets by transferring media associated with fast-developing fly lines over the course of four selection cycles. In each cycle, we used sterile eggs from the same inbred population, and assayed mean fly eclosion times. Ultimately, flies eclosed seven to twelve hours earlier, depending on the diet, but microbiome engineering had no effect relative to a random-selection control treatment. 16S rRNA gene sequencing showed that the microbiome did evolve, particularly in the no sugar diet, with an increase in Shannon diversity over time. Thus, while microbiome evolution did affect host eclosion times, these effects were incidental. Instead, any experimentally enforced selection effects were swamped by uncontrolled microbial evolution, likely resulting in its adaptation to the media. These results imply that selection on host phenotypes must be strong enough to overcome other selection pressures simultaneously operating on the microbiome. The independent evolutionary trajectories of the host and the microbiome may limit the extent to which indirect selection on the microbiome can ultimately affect host phenotype. Random-selection lines accounting for independent microbial evolution are essential for experimental microbiome engineering studies.
Arora et al. (2020) Effects of microbial evolution dominate those of experimental host-mediated indirect selection. PeerJ 8:e9350 https://doi.org/10.7717/peerj.9350
Spawning of French grunts, Haemulon flavolineatum, in recirculating aquarium systems
Background Because the French grunt, Haemulon flavolineatum, is an ecologically important reef fish prized by both recreational anglers and public aquariums, the wild population requires limits on harvests. Yet, the environmental conditions conducive for French grunt spawning in aquarium settings is not well understood. Therefore, the goal of this study was to document the conditions leading to voluntary spawning and the number of eggs produced by French grunts without the use of hormones or artificial insemination. Methods We hypothesized and verified that it is possible for French grunts to spontaneously spawn in human care. Forty individuals were collected around the Florida Keys and haphazardly stocked in five recirculating seawater systems each containing two 250-L circular tanks. Over the course of 87 days, eggs were collected daily from each system and environmental parameters were monitored. Results Total daily number of eggs released ranged from 0 to 207,644 eggs. Of the observed environmental parameters, temperature and alkalinity had the greatest impact on number of eggs released. This study demonstrates that it is possible for French grunts to reproduce in captivity with little environmental manipulation, thus an ideal candidate to culture for the zoo/aquarium industry.
Maurer et al. (2020) Spawning of French grunts, Haemulon flavolineatum, in recirculating aquarium systems. PeerJ 8:e9417 https://doi.org/10.7717/peerj.9417
Habitat association in the critically endangered Mangshan pit viper (Protobothrops mangshanensis), a species endemic to China
Habitat directly affects the population size and geographical distribution of wildlife species, including the Mangshan pit viper (Protobothrops mangshanensis), a critically endangered snake species endemic to China. We searched for Mangshan pit viper using randomly arranged transects in their area of distribution and assessed their habitat association using plots, with the goals of gaining a better understanding of the habitat features associated with P. mangshanensis detection and determining if the association with these features varies across season. We conducted transect surveys, found 48 individual snakes, and measured 11 habitat variables seasonally in used and random plots in Hunan Mangshan National Nature Reserve over a period of 5 years (2012–2016). The important habitat variables for predicting Mangshan pit viper detection were fallen log density, shrub density, leaf litter cover, herb cover and distance to water. In spring, summer and autumn, Mangshan pit viper detection was always positively associated with fallen log density. In summer, Mangshan pit viper detection was related to such habitats with high canopy cover, high shrub density and high herb cover. In autumn, snakes generally occurred in habitats near water in areas with high fallen log density and tall shrubs height. Our study is the first to demonstrate the relationship between Mangshan pit viper detection and specific habitat components. Mangshan pit viper detection was associated with habitat features such as with a relatively high fallen log density and shrub density, moderately high leaf litter cover, sites near stream, and with lower herb cover. The pattern of the relationship between snakes and habitats was not consistent across the seasons. Identifying the habitat features associated with Mangshan pit viper detection can better inform the forestry department on managing natural reserves to meet the habitat requirements for this critically endangered snake species.
Zhang et al. (2020) Habitat association in the critically endangered Mangshan pit viper (Protobothrops mangshanensis), a species endemic to China. PeerJ 8:e9439 https://doi.org/10.7717/peerj.9439