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The genus Diplodus presents multiple cases of taxonomic conjecture. Among these the D. cervinus complex was previously described as comprising three subspecies that are now regarded as separate species: Diplodus cervinus, Diplodus hottentotus and Diplodus omanensis. Diplodus hottentotus exhibits a clear break in its distribution around the Benguela Current system, prompting speculation that Angolan and South African populations flanking this area may be isolated and warrant formal taxonomic distinction. This study reports the first integrated genetic [mitochondrial (mt)DNA and nuclear microsatellite] and morphological (morphometric, meristic and colouration) study to assess patterns of divergence between populations in the two regions. High levels of cytonuclear divergence between the populations support a prolonged period of genetic isolation, with the sharing of only one mtDNA haplotype (12 haplotypes were fully sorted between regions) attributed to retention of ancestral polymorphism. Fish from the two regions were significantly differentiated at a number of morphometric (69·5%) and meristic (46%) characters. In addition, Angolan and South African fish exhibited reciprocally diagnostic colouration patterns that were more similar to Mediterranean and Indian Ocean congeners, respectively. Based on the congruent genetic and phenotypic diversity we suggest that the use of hottentotus, whether for full species or subspecies status, should be restricted to South African D. cervinus to reflect their status as a distinct species‐like unit, while the relationship between Angolan and Atlantic–Mediterranean D. cervinus will require further demo‐genetic analysis. This study highlights the utility of integrated genetic and morphological approaches to assess taxonomic diversity within the biogeographically dynamic Benguela Current region. [ABSTRACT FROM AUTHOR]

Blacktail seabream Diplodus capensis were sampled from proximate (10 km apart) exploited and unexploited areas in southern Angola to compare their population structures and life-history parameters. Females dominated the larger size and older age classes in the unexploited area. In the exploited area the length and age frequency distributions were more equitable, but there was a lack of large and old individuals in this area due to the selective nature of fishing gear. Growth zone deposition rate was validated as being annual using mark-recapture of chemically injected (oxytetracycline) fish. In the unexploited area, females attained larger sizes and greater ages than males; however, growth and longevity were more equitable between the sexes in the exploited area. Length- and age-at-50% maturity were similar between the sexes in both areas. The sex ratio was heavily female-skewed (1:4.7) in the unexploited area but less so in the exploited area (1:2.2). Although the growth curves were significantly different for fish between areas, this was likely due to a reduction in longevity rather than a physiological change in growth. The length- and age-at-50% maturity was also similar between areas, indicating that this species either does not have the ability to respond to exploitation through physiological change in these life-history characteristics, or that the current level of exploitation is not high enough to elicit such a response. However, the female dominance in the smallest size class in the exploited area (compared to the unexploited area) indicated that a threshold may have been reached, and that this species responds to exploitation by increasing the relative number of fish that mature as females. [ABSTRACT FROM PUBLISHER]

The sparid Dentex macrophthalmus is a widespread, important fishery species along most of the West African coast from southern Namibia to the Mediterranean. In southern Angola it is an important artisanal species targeted predominantly by handline fishers. A biological and fisheries study was conducted on this species in southern Angola between June 2008 and July 2009. It was the dominant species in the artisanal fishery, accounting for 99% of the sparids captured and 67% (by mass) of the total catch. The life history of D. macrophthalmus was characterised by slow growth (females: Lt = 309[1 - e-0.06(t + 5.43)], males: Lt = 248[1 - e-0.16(t - 1.77)]), advanced age at maturity (females: 7.4 years, males: 6.0 years) and high longevity (females: 36 years, males: 38 years). The sex ratio was 1:1 male:female. The length- and age-frequency distributions and macroscopic observations suggested that the species is a late gonochorist. Males and females reached 50% maturity at 151 and 166 mm fork length respectively. Although individuals with ripe gonads were found during most of the year, the peak spawning period appeared to be in December and January. Despite a life history that renders D. macrophthal-mus vulnerable to overexploitation, only 38% of artisanal fishers noticed a decline in the catches of this species. Potential reasons for this include: technology creep; limited pressure on the juvenile portion of the stock as a result of late recruitment (above the length of 50% maturity); the 'basin affect', whereby depleted areas are reseeded by areas (e.g. deeper water) inaccessible to the linefishery; and a deep-water reserve of large individuals. It is recommended that precautionary management strategies be implemented until the age estimates are revised by the countries in which this species forms significant fisheries. [ABSTRACT FROM AUTHOR]

The West Coast dusky kob Argyrosomus coronus is an understudied yet important fishery species in Angola. During a five-year study (2005-2009), the species was recorded in all fishery sectors, but was most important in the inshore recreational fishery in southern Angola (Cunene Estuary to Namibe). Early juveniles (<300 mm total length, TL) were captured in the offshore artisanal fishery at Praia Pinda, whereas juveniles (300-600 mm TL), subadults (600-870 mm TL) and adults (>870 mm TL) were captured in all fisheries as far north as Namibe, and shoals of large adult fish (>1 000 mm TL) were occasionally captured in the offshore purse-seine commercial fishery between the Cunene Estuary and Lucira. Because some Argyrosomus species are morphologically cryptic, a DNA barcoding method was used to confirm the taxonomic status of the biological samples used in this study. The male:female sex ratio of examined samples was 1:1.4 (n = 225). The length-at-50% maturity was 823 mm and 904 mm TL for males and females respectively. Age-at-50% maturity was 4.4 and 4.3 years for males and females respectively. The periodicity of otolith ring formation was confirmed to be one year using a marginal zone and a chemical marking analysis. Growth (in mm TL) was best described by: Lt = 1 826(1-e-0.12(t + 1.60)). Argyrosomus coronus fed predominantly on fish, mainly Sardinella aurita (62% frequency of occurrence). Early juveniles appeared to frequent the offshore zone (50-100 m depth), moving into the inshore region at approximately 300 mm TL. Juveniles and subadults were resident (57% recaptured at the same site) and were particularly abundant around the mouth of the Cunene Estuary as well as in central and northern Namibia. Adults undertake migrations that correspond with the movement of the Angola-Benguela frontal zone, moving north as far as Gabon in winter and returning to southern Angola in spring, when spawning appeared to take place offshore. There are currently no catch restrictions on A. coronus in Angolan waters. However, declining catches and increasing fishing effort suggest that some management intervention is required, commencing with a proposed closure of the Cunene Estuary mouth region to fishing. [ABSTRACT FROM AUTHOR]

BACKGROUND: The efficacy of a single dose of pegylated interferon lambda in preventing clinical events among outpatients with acute symptomatic coronavirus disease 2019 (Covid-19) is unclear. METHODS: We conducted a randomized, controlled, adaptive platform trial involving predominantly vaccinated adults with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Brazil and Canada. Outpatients who presented with an acute clinical condition consistent with Covid-19 within 7 days after the onset of symptoms received either pegylated interferon lambda (single subcutaneous injection, 180/xg) or placebo (single injection or oral). The primary composite outcome was hospitalization (or transfer to a tertiary hospital) or an emergency department visit (observation for >6 hours) due to Covid-19 within 28 days after randomization. RESULTS: A total of 933 patients were assigned to receive pegylated interferon lambda (2 were subsequently excluded owing to protocol deviations) and 1018 were assigned to receive placebo. Overall, 83% of the patients had been vaccinated, and during the trial, multiple SARS-CoV-2 variants had emerged. A total of 25 of 931 patients (2.7%) in the interferon group had a primary-outcome event, as compared with 57 of 1018 (5.6%) in the placebo group, a difference of 51% (relative risk, 0.49; 95% Bayesian credible interval, 0.30 to 0.76; posterior probability of superiority to placebo, >99.9%). Results were generally consistent in analyses of secondary outcomes, including time to hospitalization for Covid-19 (hazard ratio, 0.57; 95% Bayesian credible interval, 0.33 to 0.95) and Covid-19-related hospitalization or death (hazard ratio, 0.59; 95% Bayesian credible interval, 0.35 to 0.97). The effects were consistent across dominant variants and independent of vaccination status. Among patients with a high viral load at baseline, those who received pegylated interferon lambda had lower viral loads by day 7 than those who received placebo. The incidence of adverse events was similar in the two groups. CONCLUSIONS: Among predominantly vaccinated outpatients with Covid-19, the incidence of hospitalization or an emergency department visit (observation for >6 hours) was significantly lower among those who received a single dose of pegylated interferon lambda than among those who received placebo. (Funded by FastGrants and others; TOGETHER ClinicalTrials.gov number, NCT04727424.) [ABSTRACT FROM AUTHOR]

Background: The efficacy of ivermectin in preventing hospitalization or extended observation in an emergency setting among outpatients with acutely symptomatic coronavirus disease 2019 (Covid-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is unclear.Methods: We conducted a double-blind, randomized, placebo-controlled, adaptive platform trial involving symptomatic SARS-CoV-2-positive adults recruited from 12 public health clinics in Brazil. Patients who had had symptoms of Covid-19 for up to 7 days and had at least one risk factor for disease progression were randomly assigned to receive ivermectin (400 μg per kilogram of body weight) once daily for 3 days or placebo. (The trial also involved other interventions that are not reported here.) The primary composite outcome was hospitalization due to Covid-19 within 28 days after randomization or an emergency department visit due to clinical worsening of Covid-19 (defined as the participant remaining under observation for >6 hours) within 28 days after randomization.Results: A total of 3515 patients were randomly assigned to receive ivermectin (679 patients), placebo (679), or another intervention (2157). Overall, 100 patients (14.7%) in the ivermectin group had a primary-outcome event, as compared with 111 (16.3%) in the placebo group (relative risk, 0.90; 95% Bayesian credible interval, 0.70 to 1.16). Of the 211 primary-outcome events, 171 (81.0%) were hospital admissions. Findings were similar to the primary analysis in a modified intention-to-treat analysis that included only patients who received at least one dose of ivermectin or placebo (relative risk, 0.89; 95% Bayesian credible interval, 0.69 to 1.15) and in a per-protocol analysis that included only patients who reported 100% adherence to the assigned regimen (relative risk, 0.94; 95% Bayesian credible interval, 0.67 to 1.35). There were no significant effects of ivermectin use on secondary outcomes or adverse events.Conclusions: Treatment with ivermectin did not result in a lower incidence of medical admission to a hospital due to progression of Covid-19 or of prolonged emergency department observation among outpatients with an early diagnosis of Covid-19. (Funded by FastGrants and the Rainwater Charitable Foundation; TOGETHER ClinicalTrials.gov number, NCT04727424.). [ABSTRACT FROM AUTHOR]

Delay discounting refers to the decrease in subjective value of a reward as the delay until its receipt increases. In the present study we assessed the effects of the sequence of delay blocks (increasing or decreasing) on discounting and the data systematicity using a titrating procedure with human participants. All participants completed the delay discounting task in both an increasing and decreasing sequence of delays. Delays ranged from one day to ten years. We found steeper discounting when the delays were presented in an increasing sequence compared with when they were presented in a decreasing sequence. We also found steeper discounting when participants completed the increasing sequence condition first. Our results agree with other findings reported in the literature and suggest that delay discounting may be affected by prior and subsequent experience., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Phosphorus (P) use efficiency is crucial for sorghum production. P acquisition efficiency is the most important component of P use efficiency. The early-stage evaluation of plant development is a useful tool for identifying P-efficient genotypes. This study aimed to identify sorghum hybrids that are efficient in P use efficiency and assess the genetic diversity among hybrids based on traits related to P acquisition efficiency. Thus, 38 sorghum hybrids and two inbred lines (checks) were evaluated under low and high P in a paper pouch system with nutrient solution. Biomass and root traits related to P efficiency were measured. There was no interaction between genotypes and P levels concerning all evaluated traits. The biomass and root traits, except root diameter, presented smaller means under low P than high P. Efficient and inefficient hybrids under each P level were identified. The genetic diversity assessment grouped these genotypes in different clusters. The hybrids AG1090, MSK326, AG1060, 1G100, AS 4639, DKB 540, and DKB 590 were superior under low-P and high-P. Hybrids SC121, 1236020 e 1167017 presented the lowest means than all other hybrids, under both conditions. The evaluated hybrids showed phenotypic diversity for traits related to P acquisition, such as root length and root surface area, which can be useful for establishing selection strategies for sorghum breeding programs and increasing P use efficiency.

The species Eugenia involucrata DC. is a plant native to Brazil and is traditionally used for intestinal problems, however, little research has documented about its biological potential and phytochemical profile. Thus, the objective of this study was to carry out preliminary phytochemical prospecting, antimicrobial and antioxidant potential of E. involucrata extracts. Using the E. involucrata leaves, aqueous and organic extracts were obtained using the following solvents (ethanol, methanol, hexane, acetone, dichloromethane and ethyl acetate). The phytochemical prospecting detected the presence of saponins, steroids, flavonoids and tannins in the extracts. Ethanolic and methanolic extracts presented antimicrobial activity for most of the bacterial strains tested, as well as for yeast Candida albicans, with concentrations between 3.12 and 50 mg/mL. The ethanolic and metanolic extract presented high free radical sequestration potential (>90%). The methanol extract showed an IC50 value statistically equal to that found for the commercial antioxidant BHT (p <0.05). The crude extracts obtained with ethanol and methanol were the most promising. These results suggest that methanolic, ethanolic and aqueous extracts are a promising source of natural bioactive.

Sorghum grain yield can be significantly affected by climatic changes, especially drought and high temperature. The purpose of this study was to evaluate hybrids of grain sorghum grown under normal irrigation conditions or water stress in order to select those likely to be more tolerant of drought. Forty-nine hybrids were grown in a randomized block design experiment, with three replications. The plots consisted of four rows of 5 m length. Grain yield, weight of 1000 grains, harvest index, days to flowering, and plant height were measured. All of these characteristics were affected by water stress; however, grain yield showed the largest relative reduction. Comparison of the various genotypes showed that some hybrids had an acceptable grain yield under water stress, and maintained a high average yield compared to growth without stress. Several hybrids gave better grain yield than commercial check cultivars: 1170090, 1170092, 1170064, 1167026, 1167064, 1170093, 1167008, 1167029, 0009061, 1167092, 1105647, and 1170019 stood out for their acceptable plant height, earliness, and higher productivity.

Twenty-five cultivars of grain sorghum [Sorghum bicolor (L.) Moench] were examined under both drought stress and normal conditions in 4 experiments. In each condition, genotypes were evaluated in a factorial experiment using a randomized complete block design with 3 replications. Eight drought tolerance indices including stability tolerance index, mean productivity (MP), geometric MP, harmonic mean, stress susceptibility index, tolerance index, yield index, and yield stability index were estimated for each genotype based on grain yield under drought (Ys) and irrigated conditions (Yp). The results indicated that there were positive and significant correlations among Yp and Ys with geometric MP, MP, harmonic mean, and stability tolerance index, indicating that these factors are better predictors of Yp and Ys than tolerance index, stress susceptibility index, yield stability index, and yield index. Based on adjusted means at Yp and Ys, indices geometric MP, MP, harmonic mean, and stability tolerance index, unweighted pair group method with arithmetic mean cluster and biplot analysis, the most tolerant cultivars were '9929020', '9929034', and 'N 95B'.

In order to investigate the effects of a companion's presence on resistance to change, five rats were trained under a multiple schedule comprised of components with high versus low rate of water reinforcement. After response rates became stable, water was given to the subjects prior to the experimental sessions, and these were conducted both in the absence and in the presence of a companion, which also could be responding or merely present. Results showed that the companion's presence increased resistance to satiation, mainly during the component with the higher reinforcement rate. These results suggest that the effect of the companion's presence may interact with reinforcement rate in determining response rate and resistance to satiation.

Three experiments investigated learned helplessness in rats manipulating response requirements, shock duration, and intervals between treatment and testing. In Experiment 1, rats previously exposed to uncontrollable or no shocks were tested under one of four different contingencies of negative reinforcement: FR 1 or FR 2 escape contingency for running, and FR1 escape contingency for jumping (differing for the maximum shock duration of 10s or 30s). The results showed that the uncontrollable shocks produced a clear operant learning deficit (learned helplessness effect) only when the animals were tested under the jumping FR 1 escape contingency with 10-s max shock duration. Experiment 2 isolated of the effects of uncontrollability from shock exposure per se and showed that the escape deficit observed using the FR 1 escape jumping response (10-s shock duration) was produced by the uncontrollability of shock. Experiment 3 showed that using the FR 1 jumping escape contingency in the test, the learned helplessness effect was observed one, 14 or 28 days after treatment. These results suggest that running may not be an appropriate test for learned helplessness, and that many diverging results found in the literature might be accounted for by the confounding effects of respondent and operant contingencies present when running is required of rats.

We had previously shown that GRP acts directly at the pituitary gland inhibiting basal and TRH-stimulated TSH secretion in adult male rats. In this study we showed a gender dimorphism in this response of old animals pituitaries to GRP. In both female and male young adult animals, GRP-incubated pituitaries showed approximately 50% less basal and TRH-stimulated TSH secretion to the medium, without affecting the pituitary content of TSH. However, GRP did not have any significant effect upon TSH secretion in old male rats, but the old female showed the same degree of response to GRP as the young adult female rat, regarding basal and TRH-stimulated TSH secretion, while the TSH pituitary content after GRP incubation was higher than that of the young female group. Our data suggest a loss of thyrotrope responsiveness to GRP in aged male rats that could contribute to the decrease in TSH pituitary stores leading to lower basal and TRH-stimulated TSH secretion. Meanwhile, the preservation of GRP responsiveness could help in the relative maintenance of these parameters in the old female rat.

Studies on cooperative care of offspring in callitrichid primates are biased in favor of observations in captivity. In the wild, however, individuals have to deal with environmental pressures, which may influence their social behavior. We compared the individual effort attributed to parental care offered by members of a wild group (couple, plus a subadult helper) and two captive groups (A: couple, plus an subadult helper, B: couple, plus four adult helpers) of the buffy-tufted-ear marmoset, Callithrix aurita, from weeks 1-12 after the infants' birth. The carrier (breeding male and female or helper) and the infant's feeding (food sharing and foraging for food) were recorded. Up to week four, while the wild breeding pair shared infant carrying at similar proportions, the male from captive group A carried 100% of the time. Adult helpers from group B were the main carriers. Carrying behavior extended up to week 12 only in the wild group. Food provisioning to the infant was observed earlier in the groups wild and A, but general proportion of feeding records was lower in the wild than in captivity. Energetic cost of travelling and searching for food may be associated with equal division of carrying behavior by the wild breeding pair. Higher proportions of carrying in the groups wild and B may have delayed the development of the infants' motor skills required in foraging. Our data agree with previous studies: the father's lower investment in carrying when adult helpers are present and lower contribution of subadult non-reproductive members.

The effect of substance P (SP) on thyrotropin (TSH) secretion is controversial. In this study we evaluated the effect of SP on TSH secretion by hemipituitaries of 3-month-old Wistar rats in vitro and its interaction with gastrin-releasing peptide (GRP) at equimolar concentrations (1 microM and 10 microM). TSH release was measured under basal conditions and 30 min after incubation in the absence or presence of SP, GRP or both peptides. Pituitary TSH content was also measured in the pituitary homogenate after incubation. SP at both concentrations caused a significant (P<0.05) increase in TSH secretion compared with all other groups, which was approximately 60% (1 microM) and 85% (10 microM) higher than that of the control group (23.3 +/- 3.0 ng/ml). GRP at the lower concentration did not produce a statistically significant change in TSH secretion, whereas at the concentration of 10 microM it produced a 50% reduction in TSH. GRP co-incubated with substance P completely blocked the stimulatory effect of SP at both concentrations. Pituitary TSH content decreased in the SP-treated group compared to controls (0.75 +/- 0.03 microg/hemipituitary) at the same proportion as the increase in TSH secretion, and this effect was also blocked when GRP and SP were co-incubated. In conclusion, in an in vitro system, SP increased TSH secretion acting directly at the pituitary level and this effect was blocked by GRP, suggesting that GRP is more potent than SP on TSH secretion, and that this inhibitory effect could be the predominant effect in vivo.

Urine, feces, and copulation frequency were collected from two captive muriqui females, Brachyteles arachnoides, at the Centro de Primatologia do Rio de Janeiro following the resumption of postpartum ovarian cycles. Fecal steroid profiles from seven wild muriqui females at the Estação Biologica de Caratinga, Minas Gerais, Brazil, were compared to the captive females to determine the approximate patterns of steroid excretion relative to the urinary LH peak. Hormonal profiles from one of the captive female muriquis revealed a discrete urinary LH peak. For this female, fecal progesterone increased on the same day as the urinary LH peak, while fecal estradiol increased 6 days later and urinary steroids increased 5 days later. For both captive females, the onset of fecal progesterone increase was preceded by the onset of copulations, which occurred during at least a 5-day period. The complete fecal hormonal profiles of the one captive female for which continuos data were available were similar to those found in wild muriqui monkeys, with the onset of an increase in sustained progesterone levels occurring several days prior to the onset of sustained estradiol increase. These patterns suggest that fecal progesterone may be excreted rapidly in this species. The onset of sustained increase in fecal progesterone levels, together with the consistent delay in the onset of the sustained increase in estradiol, may provide the best indicators of the periovulatory period for muriqui females.

Quantitative EEG changes were studied during cocaine withdrawal in 36 subjects. All subjects had used cocaine orally (n = 28) or intravenously (n = 8) within 48 h of admission to an inpatient unit. EEGs were recorded 2 and 6 days following admission. Nine subjects returned for a 1-month follow-up EEG. Modal EEG frequency significantly decreased on day 6 compared to day 2. The most dramatic change in both absolute and relative power from day 2 to day 6 was a decrease in the beta 2 (18-26 Hz) band. Those subjects who returned for the 4-week follow-up showed a further decrease in beta 2 power. Power in the beta 2 band was significantly greater for the intravenous users than for the smokers, and the decrease in power from day 2 to day 6 was also significantly greater in this group. While acute effects of cocaine on the EEG have been reported to last only several hours, this study indicates that chronic use may cause longer lasting neuroadaptive changes, particularly in those who have used cocaine intravenously.

The technique of countercurrent immunoelectrophoresis (CI), using the N-acetyl glucosamine-binding lectin from Helix pomatia, provided a rapid, sensitive, inexpensive, specific and reliable method for assaying blood group A-like substances in both bacterial and viral vaccines. Blood group A-like substance was detected in the pneumococcal polysaccharide vaccine manufactured by Merck Sharp & Dohme up to 1981 and in a staphylococcus vaccine ( Staphage Lysate) manufactured by Delmont Laboratories. Other US licensed vaccines, including diphtheria and tetanus toxoids, pertussis, meningococcal polysaccharide and influenza vaccines, did not contain detectable amounts of this substance. Human anti-A globulins did not provide a satisfactory reagent for the CI assay because they contained precipitating activities to the vaccine components.