A survey of aquatic macroinvertebrates in a river from the dry corridor of Nicaragua using biological indices and DNA barcoding.

Aquatic macroinvertebrates are widely used as indicators for water quality assessment around the world. Modern strategies for environmental assessment implement molecular analysis to delimitate species of aquatic macroinvertebrates. Delimitation methods have been established to determine boundaries between species units using sequencing data from DNA barcodes and serve as first exploratory tools for taxonomic revisions. This is useful in regions such as the neotropics where aquatic macroinvertebrate habitats are threatened by human interference and DNA databases remain understudied. We asked whether the biodiversity of aquatic macroinvertebrates in a stream in Nicaragua, within the Central American Dry Corridor, could be characterized with biological indices and DNA barcoding. In this study, we combined regional biological indices (BMWP-CR, IBF-SV-2010) along with distance-based (ASAP, BIN) and tree-based (GMYC, bPTP) delimitation methods, as well as nucleotide BLAST in public barcode databases. We collected samples from the upper, middle, and low reaches of the Petaquilla river. The three sites presented excellent water quality with the BMWP-CR index, but evidence of high organic pollution was found in the middle reach with the IBF-SV-2010 index. We report a total of 219 COI sequences successfully generated from 18 families and 8 orders. Operational taxonomic units (OTUs) designation ranged from 69 to 73 using the four methods, with a congruency of 92% for barcode assignation. Nucleotide BLAST identified 14 species (27.4% of barcodes) and 33 genera (39.3% of barcodes) from query sequences in GenBank and BOLD system databases. This small number of identified OTUs may be explained by the paucity of molecular data from the Neotropical region. Our study provides valuable information about the characterization of macroinvertebrate families that are important biological indicators for the assessment of water quality in Nicaragua. The application of molecular approaches will allow the study of local diversity and further improve the application of molecular techniques for biomonitoring.

SARS-CoV-2 prevalence at eight urban health clinics in Nicaragua: possible implications for the COVID-19 pandemic.

Objective: To assess the prevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in selected health clinics in the three largest urban areas in Nicaragua, where data regarding coronavirus disease 2019 (COVID-19) testing, morbidity and mortality is severely limited. Methods: In this cross-sectional study, participants were tested for SARS-CoV-2 RNA by loop-mediated isothermal amplification (LAMP), and were tested for antibodies using immunoassays. A questionnaire recorded subjects' COVID-19-associated symptoms and risk factors. Data were collected from 22 February to 19 March 2021, 1 year after the first confirmed cases of SARS-CoV-2 in Nicaragua. Study participants were enrolled while attending routine check-ups or seeking care unrelated to COVID-19. Study participation was random and voluntary. All patients were eligible to participate. Symptom history was not part of the eligibility criteria. Results: The prevalence of current SARS-CoV-2 infection was high (14%, LAMP-positive/seronegative). Antibody testing showed higher overall seroprevalence (38%). Cough was the symptom most strongly associated with being LAMP-positive (odds ratio 3.57, 95% confidence interval 2.65-4.81). Loss of smell had the highest positive predictive value, and was significantly associated with being LAMP-positive. Conclusion: The prevalence of current SARS-CoV-2 infection and seropositivity were fairly high. More than half of the sample population had evidence of current or past infection. Knowledge of this previously unknown elevated level of infection is crucial for healthcare providers and policy makers.

A Systematic Review and Quantitative Analysis of Interteaching.

Interteaching is a behavioral teaching method that departs from the traditional lecture format (Boyce & Hineline in BA 25:215-226, 2002). We updated and expanded previous interteaching reviews and conducted a meta-analysis on its effectiveness. Systematic searches identified 38 relevant studies spanning the years 2005-2018. The majority of these studies were conducted in undergraduate face-to-face courses. The most common independent variables were manipulations of the configuration of interteaching or comparisons to traditional-lecture format. The most common dependent variables were quiz or examination scores. Only 24% of all studies implemented at least five of the seven components of interteaching. Prep guides, discussions, record sheets, and frequent assessments were the most commonly implemented. Meta-analyses indicated that interteaching is more effective than traditional lecture or other control conditions, with an overall large effect size. Furthermore, variations in the configuration of the interteaching components do not seem to substantially limit its effectiveness, as long as the discussion component is included. Future research informed by the present review includes: (a) investigating the efficacy of interteaching in additional academic areas, online environments, workplace training, and continuing education, (b) testing alternative outcome measures, generalization, and procedural integrity, (c) conducting systematic component analyses, and (d) measuring social validity from the instructor's perspective. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10864-021-09452-3.

Prevalence and risk factors for SARS-CoV-2 infection in children with and without symptoms seeking care in Managua, Nicaragua: results of a cross-sectional survey.

OBJECTIVE: This study aimed to capture key epidemiological data on SARS-CoV-2 infection in Nicaraguan children (≤18 years) seeking medical care, between 6 October and 16 November 2020. DESIGN: In this cross-sectional study, 418 children were recruited: 319 with symptoms characteristic of COVID-19 and 99 with no symptoms of illness. Children were tested for SARS-CoV-2 RNA using loop-mediated isothermal amplification. A questionnaire was employed to identify symptoms, risk factors, comorbidities and COVID-19 prevention measures. SETTING: Research was carried out in four hospitals and two clinics in Managua, Nicaragua, where schools and businesses remained open throughout the COVID-19 pandemic. PARTICIPANTS: Children were enrolled into a possible COVID-19 group if presenting with clinical symptoms. A comparison group included children lacking any COVID-19 symptoms attending routine check-ups or seeking care for issues unrelated to COVID-19. RESULTS: A high prevalence (43%) of SARS-CoV-2 infection was found, which was relatively equivalent in symptomatic and non-symptomatic children. Age distribution was similar between symptomatic and non-symptomatic children testing positive for SARS-CoV-2. Symptomatic children who tested positive for SARS-CoV-2 were 2.7 times more likely to have diarrhoea (26.7% in positive vs 12.0% in negative; OR=2.7 (95% CI 1.5 to 4.8), p=0.001) and were 2.0 times more likely to have myalgia (17.8% in positive vs 9.8% in negative; OR=2.0 (95% CI 1.0 to 3.8), p=0.04). Children with COVID-19 symptoms, who tested positive for SARS-CoV-2, were more likely to be under age 5 years and to have a pre-existing comorbid condition than children who tested positive but did not have symptoms. CONCLUSIONS: This is the first paediatric study to provide laboratory-confirmed data on SARS-CoV-2 infection in Nicaragua, crucial for paediatric health services planning and a successful COVID-19 response. The high prevalence of the virus suggests widespread and sustained community transmission, underscoring the urgent need for robust data on the true extent of SARS-CoV-2 infection throughout Nicaragua.

First report on prevalence of SARS-CoV-2 infection among health-care workers in Nicaragua.

The Nicaraguan COVID-19 situation is exceptional for Central America. The government restricts testing and testing supplies, and the true extent of the coronavirus crisis remains unknown. Dozens of deaths have been reported among health-care workers. However, statistics on the crisis' effect on health-care workers and their risk of being infected with SARS-CoV-2 are lacking. We aimed to estimate the prevalence of SARS-CoV-2 infection in health-care workers and to examine correlations with risk factors such as age, sex and comorbidities. Study participants (N = 402, median age 38.48 years) included physicians, nurses and medical assistants, from public and private hospitals, independent of symptom presentation. SARS-CoV-2 was detected on saliva samples using the loop-mediated isothermal amplification assay. A questionnaire was employed to determine subjects' COVID-19-associated symptoms and their vulnerability to complications from risk factors such as age, sex, professional role and comorbidities. The study was performed five weeks into the exponential growth period in Nicaragua. We discovered that 30.35% of health-care workers participating in our study had been infected with SARS-CoV-2. A large percentage (54.92%) of those who tested positive were asymptomatic and were still treating patients. Nearly 50% of health-care workers who tested positive were under 40, an astonishing 30.33% reported having at least one comorbidity. In our study, sex and age are important risk factors for the probability of testing positive for SARS-CoV-2 with significance being greatest among those between 30 and 40 years of age. In general, being male resulted in higher risk. Our data are the first non-governmental data obtained in Nicaragua. They shed light on several important aspects of COVID-19 in an underdeveloped nation whose government has implemented a herd-immunity strategy, while lacking an adequate healthcare system and sufficient PPE for health-care workers. These data are important for creating policies for containing the spread of SARS-CoV-2.

Effects of Somatic Methylation in Colonic Polyps on Risk of Developing Metachronous Advanced Colorectal Lesions.

The utility of molecular markers for predicting the risk of metachronous advanced colorectal lesions (MACLs) remains poorly investigated. We examined the relationship between somatic hypermethylation in polyps at baseline and the risk of developing MACL. This retrospective cohort study included 281 consecutive patients with colonic polyps who were enrolled between 2007 and 2009 and followed-up until 2014. MACLs were defined as adenomas of ≥10 mm, high-grade dysplasia, or with a villous component; and serrated lesions of ≥10 mm or with dysplasia. In total, 595 polyps were removed at baseline colonoscopy and analyzed for pathological characteristics and CpG island methylator phenotype (CIMP) using the MS-MLPA (Methylation-Specific -- Multiplex Ligation-dependent Probe Amplification) technique. Forty-five patients (16.0%) showed at least one CIMP+ polyp. MACL risk was higher in patients with CIMP+ polyps (odds ratio (OR), 4.50; 95% CI, 1.78-11.4; p = 0.002). Patients with CIMP+ polyps also exhibited shorter time to MACL development (33.8 months vs. 50.1 months; p < 0.001), even with adjustment for polyp size and number (OR, 2.40; 95% CI, 1.33-4.34). Adding CIMP analysis improved the sensitivity (57.0% to 70.9%), negative predictive value (71.1% to 77.3%), and overall accuracy (49.8% to 52.0%) for MACL risk estimation. These results highlight that CIMP may be a useful marker for endoscopic surveillance.

What's in a Click? The Efficacy of Conditioned Reinforcement in Applied Animal Training: A Systematic Review and Meta-Analysis.

A conditioned reinforcer is a stimulus that acquired its effectiveness to increase and maintain a target behavior on the basis of the individual's history-e.g., pairings with other reinforcers. This systematic review synthesized findings on conditioned reinforcement in the applied animal training field. Thirty-four studies were included in the review and six studies were eligible for a meta-analysis on the effectiveness of behavioral interventions that implemented conditioned reinforcement (e.g., clicks, spoken word, or whistles paired with food). The majority of studies investigated conditioned reinforcement with dogs (47%, n = 16) and horses (30%, n = 10) implementing click-food pairings. All other species (cats, cattle, fish, goats, and monkeys) were equally distributed across types of conditioned (e.g., clicker or spoken word) and unconditioned reinforcers (e.g., food, water, or tactile). A meta-analysis on the effectiveness of conditioned reinforcement in behavioral interventions found a medium summary effect size (Tau-U 0.77; CI95% = [0.53, 0.89]), when comparing baseline, where no training was done, and treatment levels. Moderators of conditioned reinforcement effectiveness were species (e.g., horses) and research design (e.g., multiple-baseline designs). The small number of intervention-focused studies available limits the present findings and highlights the need for more systematic research into the effectiveness of conditioned reinforcement across species.

We Don't Train in Vain: A Systematic Review and Meta-Analysis of Human and Canine Caregiver Training.

The present review assessed the current knowledge regarding caregiver- training effectiveness for human and human-canine dyads. Most canine-related sources (66%; n = 19) were case studies reporting a decrease of learner undesired behavior when using oral instruction (21%; n = 6). Most human-related research used single-case designs (57%; n = 26) reporting an increase in desired learner behavior (22%; n = 10) when caregivers received multi-component training packages (17%, n = 8). The meta-analysis (n = 18) revealed that interventions had a large effect (Hedges' g = 0.88, 95%CI [0.68-1.07]), with packages yielding a slightly larger moderate effect (Hedges' g = 0.76, 95%CI [0.60-0.91]) than oral instruction alone (Hedges' g = 0.74, 95%CI [0.32-1,15]). Although the effectiveness of caregiver training is promising, the results should be interpreted cautiously. Due to the preponderance of case studies within canine literature and the insufficient reporting of data across sources, only few studies could be included in the meta-analysis. Overall, more systematic and comparative research regarding the efficacy of caregivers in behavior change programs across species is needed.

Streptococcus pneumoniae Serotype 3 in Mexico (1994 to 2017): Decrease of the Unusual Clonal Complex 4909 Lineage following PCV13 Introduction.

Streptococcus pneumoniae expressing serotype 3 has a high virulence and a high case fatality ratio. Most studies of serotype 3 pneumococci have focused on a single lineage, the widespread sequence type 180 (ST180). To evaluate the serotype 3 lineages causing infections in Mexico, we characterized 196 isolates recovered from 1994 to 2017. The isolates were mostly susceptible to all antimicrobials tested. A single meningitis isolate was resistant to penicillin, and the resistance to erythromycin was 5.2%. The isolates represented the widely disseminated clonal complex 180 (CC180; n = 140), the unusual CC4909 (n = 42), CC260 (n = 11), and a few singletons (n = 3). CC260 was less frequent among pneumococcal invasive disease isolates than CC180 and CC4909 (P = 0.015). There was a decrease of CC4909 (P < 0.001) following PCV13 introduction (2012 to 2017). The CC4909 isolates were represented mostly by ST1119 (n = 40), seemingly having a restricted geographic origin, with isolates in the PubMLST database having been recovered only in Mexico, the United States, and Germany. A genomic analysis of publicly available genomes showed that ST1119 isolates have less than 32% similarity with ST180 isolates, indicating that these lineages are more separated than revealed by traditional multilocus sequence typing. Considering the suggestions of a lower efficacy of the 13-valent pneumococcal conjugate vaccine against serotype 3, the different dynamics of the two major serotype 3 lineages in Mexico following the introduction of PCV13 should be closely monitored.

Assessing Mongolian gerbil emotional behavior: effects of two shock intensities and response-independent shocks during an extended inhibitory-avoidance task.

Despite step-down inhibitory avoidance procedures that have been widely implemented in rats and mice to study learning and emotion phenomena, performance of other species in these tasks has received less attention. The case of the Mongolian gerbil is of relevance considering the discrepancies in the parameters of the step-down protocols implemented, especially the wide range of foot-shock intensities (i.e., 0.4-4.0 mA), and the lack of information on long-term performance, extinction effects, and behavioral patterning during these tasks. Experiment 1 aimed to (a) characterize gerbils' acquisition, extinction, and steady-state performance during a multisession (i.e., extended) step-down protocol adapted for implementation in a commercially-available behavioral package (Video Fear Conditioning System-MED Associates Fairfax, VT, USA), and (b) compare gerbils' performance in this task with two shock intensities - 0.5 vs. 1.0 mA-considered in the low-to-mid range. Results indicated that the 1.0 mA protocol produced more reliable and clear evidence of avoidance learning, extinction, and reacquisition in terms of increments in freezing and on-platform time as well as suppression of platform descent. Experiment 2 aimed to (a) assess whether an alternate protocol consisting of a random delivery of foot shocks could replicate the effects of Experiment 1 and (b) characterize gerbils' exploratory behavior during the step-down task (jumping, digging, rearing, and probing). Random shocks did not reproduce the effects observed with the first protocol. The data also indicated that a change from random to response-dependent shocks affects (a) the length of each visit to the platform, but not the frequency of platform descends or freezing time, and (b) the patterns of exploratory behavior, namely, suppression of digging and rearing, as well as increments in probing and jumping. Overall, the study demonstrated the feasibility of the extended step-down protocol for studying steady performance, extinction, and reacquisition of avoidance behavior in gerbils, which could be easily implemented in a commercially available system. The observation that 1.0 mA shocks produced a clear and consistent avoidance behavior suggests that implementation of higher intensities is unnecessary for reproducing aversive-conditioning effects in this species. The observed patterning of freezing, platform descents, and exploratory responses produced by the change from random to periodic shocks may relate to the active defensive system of the gerbil. Of special interest is the probing behavior, which could be interpreted as risk assessment and has not been reported in other rodent species exposed to step-down and similar tasks.

Accuracy of the volume-viscosity swallow test for clinical screening of oropharyngeal dysphagia and aspiration.

AIMS: To determine the accuracy of the bedside volume-viscosity swallow test (V-VST) for clinical screening of impaired safety and efficacy of deglutition. METHODS: We studied 85 patients with dysphagia and 12 healthy subjects. Series of 5-20 mL nectar (295.02 mPa.s), liquid (21.61 mPa.s) and pudding (3682.21 mPa.s) bolus were administered during the V-VST and videofluoroscopy. Cough, fall in oxygen saturation > or =3%, and voice changes were considered signs of impaired safety, and piecemeal deglutition and oropharyngeal residue, signs of impaired efficacy. RESULTS: Videofluoroscopy showed patients had prolonged swallow response (> or =1064 ms); 52.1% had safe swallow at nectar, 32.9%, at liquid (p<0.05), and 80.6% at pudding viscosity (p<0.05); 29.4% had aspirations, and 45.8% oropharyngeal residue. The V-VST showed 83.7% sensitivity and 64.7% specificity for bolus penetration into the larynx and 100% sensitivity and 28.8% specificity for aspiration. Sensitivity of V-VST was 69.2% for residue, 88.4% for piecemeal deglutition, and 84.6% for identifying patients whose deglutition improved by enhancing bolus viscosity. Specificity was 80.6%, 87.5%, and 73.7%, respectively. CONCLUSIONS: The V-VST is a sensitive clinical method to identify patients with dysphagia at risk for respiratory and nutritional complications, and patients whose deglutition could be improved by enhancing bolus viscosity. Patients with a positive test should undergo videofluoroscopy.

Improved SNR of phased-array PERES coils via simulation study.

A computational comparison of signal-to-noise ratio (SNR) was performed between a conventional phased array of two circular-shaped coils and a petal resonator surface array. The quasi-static model and phased-array optimum SNR were combined to derive an SNR formula for each array. Analysis of mutual inductance between coil petals was carried out to compute the optimal coil separation and optimum number of petal coils. Mutual interaction between coil arrays was not included in the model because this does not drastically affect coil performance. Phased arrays of PERES coils show a 114% improvement in SNR over that of the simplest circular configuration.

Clinical, genetic and immunologic analysis of a family affected by ozena.

Primary atrophic rhinitis is a chronic inflammation of the nasal mucosa characterized by atrophy of the mucous and bony tissue of the turbinates and by a thick, dense secretion, which quickly forms a characteristically fetid-smelling, greenish crust. We report the results of the clinical, genetic and immunologic investigations performed on eight subjects (three with ozena and five asymptomatic), members of the same familial group. The presence of the disease in the family fits well with dominant inheritance. All the culture specimens from the patients affected by ozena were positive for Klebsiella ozaenae, and one of them was also positive for Pseudomonas aeruginosa. All the three patients with ozena and two of the five apparently unaffected family members were positive for antinuclear antibodies. Immunoblotting showed a reactivity to a 50-kD protein, which was not identified by the common, recognized nuclear autoantigens. This was present in one of the three patients and three of the five other family members. Positivity for IgG-class anticardiolipins was correlated with disease manifestation in that it was found in two of the three patients and only in one of the five asymptomatic family members. The hypothesis of a genetic factor that could drive the chronicity of the inflammatory pattern of a pre-existing infectious nasal disease is suggested.