University of Guam

Coral-dinoflagellate symbiosis underpins coral reef resilience and influences conservation success, given the relationship's role in coral bleaching. Here, we transplanted Guam's dominant staghorn coral, Acropora pulchra, across four coral gardens and monitored their endosymbiotic dinoflagellates (family Symbiodiniaceae) for ∼15 months (May 2021–August 2022). Transplantation and predation resulted in temporary symbiotic destabilization, as signaled by increased cell roughness and decreased cell density. Eventually, the Symbiodiniaceae phenotypic profile mostly converged with the wild population, although cell density and red fluorescing photopigments remained modified. In March, corals paled, which allowed us to evaluate the Symbiodiniaceae assemblage's relationship with host color. Interestingly, cell density was not the most informative when predicting host color. Instead, fluorescence from antioxidant-associated pigments were most informative. We conclude that Symbiodiniaceae phenotypic traits respond differently depending on the condition, supporting their development as acclimatization bioindicators.

The roughskin dogfish Centroscymnus owstonii, a deep‐sea shark, has a patchy global distribution, with most knowledge stemming from incidentally captured specimens. Using a deep‐sea remote lander video system, we observed multiple C. owstonii individuals alive on the footage at 1054 m off Little Cayman, Cayman Islands, Western Atlantic Ocean, marking, to our knowledge, the first record of the species in the Greater Antilles, central Caribbean Sea, while also adding a new species locality record for the Cayman Islands. This study expands our knowledge of the distribution of the roughskin dogfish in the region, and highlights the utility of video lander systems for enhancing and expanding our understanding of the biology and diversity of deep‐sea sharks.

Understanding how environmental stressors impact fisheries is imperative for the sustainable management of our marine resources. Synchrony in inter-annual growth patterns among individuals and populations has been identified across large spatial scales, both within and among species. This synchrony indicates a detectable sensitivity to changes in climatic or environmental conditions. We explored within-region effects of environmental and climatic variability using inter-annual otolith growth rates (increments) in a tropical coral reef fish, Naso unicornis. Dendrochronology techniques were applied to remove age-specific growth effects and extract a high-frequency variability signal indicative of short-term environmental change. Using linear mixed-effects models, we identified best predictors of the variation in growth at two adjacent latitude subsets in the Commonwealth of the Northern Mariana Islands. We found different latitude subset growth responses for the years 2000–2013 and 2005–2017, indicating independent fluctuations in growth across latitude however, synchrony was present among individuals within a latitude range. Local environmental processes were more important than regional climatic processes for explaining N. unicornis growth in the north, but in the central islands, neither process had a clear effect. Otolith growth in fish inhabiting the north had a positive response to increased annual average sea surface temperature (SST). In adjacent central islands, otolith growth responded negatively to warmer winter SST. Baseline information for most fisheries on the direct impact of external forcings on fish, especially in tropical coral reef fisheries, remains sparse. We provide information on how climate and environment have impacted past growth with implications for future fisheries productivity monitoring.

The present study investigates the longitudinal relationships between bullying roles (bullying, passive bystanding, victimization) and moral disengagement to examine influences on the shifting role of bullying in Japanese middle school students. Participants were 271 Japanese students (Time 1: M age = 12.72, SD = .45, 136 boys and 135 girls) recruited from two public middle schools (9 classes). Five data collection occasions in Grades 7 to 9 alternated between surveys of self-reported bullying behavior (three timepoints) and moral disengagement (two timepoints). Structural equation modeling showed that moral disengagement was reciprocally related to bullying and passive bystanding. Victimization was only related to moral disengagement in Grade 9, such that moral disengagement in June predicted increased victimization experiences in December. These findings suggest that intervention and prevention programs in schools need to actively address moral disengagement, with a focus on bystanders as well as perpetrators and victims of bullying.

Colonisation of novel habitats are important events in evolution, but the factors that initially prompt such ecological transitions are often unknown. The invasion of land by fish is an extreme habitat transition that offers an opportunity to empirically investigate the causes of major ecological transitions. The intertidal ecotone—and rock pools in particular—have been an important staging ground for transitions onto land. Classic hypotheses focus on the adverse abiotic conditions of rock pools at low tide as the instigator of fish voluntarily stranding themselves out of water, which can then lead to the evolution of an amphibious lifestyle. To test these hypotheses, we studied the abiotic conditions of 54 rock pools on the island of Guam where there are various species of aquatic, amphibious and terrestrial blenny fishes. We found little support for the expected deterioration of abiotic conditions in standing pools at low tide (salinity, pH and oxygen), and fish were not seen to be excluded from those pools that were found to exhibit poor abiotic conditions (temperature, salinity and pH). Hypoxia was the only factor that might account for the absence of blennies from certain rock pools. Next, we experimentally measured oxygen depletion by an aquatic, mildly amphibious and highly amphibious species of blenny found on Guam in a simulated rockpool to infer the proportion of rock pools at low tide outside the tolerable range of blennies. Rock pools were found to have oxygen levels within the requirements of most blennies and those of other marine fishes reported in the literature. We conclude that the abiotic environment of rock pools alone was unlikely to have instigated the evolution of amphibious behaviour in blennies, at least on Guam. Instead, the broad range of abiotic conditions experienced in rock pools suggests these conditions could have primed amphibious blennies to better endure the novel conditions on land. Any ecotone typified by fluctuations or gradients in abiotic conditions is likely a key transitional environment for the invasion of novel habitats and, as such, are an important location for adaptive evolution and species diversification. Read the free Plain Language Summary for this article on the Journal blog.

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality worldwide including sub-Saharan Africa. The GALAD score, derived from Gender, Age, Lens culinaris agglutinin-reactive fraction of alpha fetoprotein, Alpha fetoprotein, and Des-carboxy-prothrombin, has high accuracy in diagnosing HCC in Asia, Europe, and North America; however, it has not been validated in an African cohort. The aim of this study was to assess the performance of the GALAD score in the diagnosis of HCC in sub-Saharan Africa. Clinical data from patients with cirrhosis (n = 93) or HCC (n = 78) from outpatient hepatology clinics at three teaching hospitals in Ghana were abstracted, and serum samples were analyzed. A logistic regression model predicting HCC status based on the GALAD score was constructed to obtain the ROC curve for GALAD. The AUC with 95% confidence interval (CI) was calculated. The median GALAD score was higher among patients with HCC versus cirrhosis controls (8.0 vs. −4.1, P < 0.01). The AUC of the GALAD score for HCC detection was 0.86 (95% CI, 0.79–0.92). At a cut-off value of −0.37, the GALAD score had a sensitivity of 0.81 and a specificity of 0.86. The AUC (95% CI) was 0.87 (0.80–0.95) and 0.81 (0.67–0.94) in hepatitis B virus–positive and hepatitis B virus–negative patients, respectively. The GALAD score has a high accuracy for HCC detection. It has great potential to improve HCC surveillance in sub-Saharan Africa where imaging resources are limited. Significance: The GALAD score or its relevant modifications have the potential to aid in improving HCC surveillance efforts in low-resource settings in sub-Saharan Africa. This could enhance early detection rates of HCC and potentially improve survival rates in resource-limited settings.

Home range size is a fundamental trait that can affect the probability of fish being harvested and, at the same time, may be affected by fishing. The relationship between home range size and fishing will impact the effectiveness of fully protected areas (FPAs), as it will influence the number of fish moving into fished areas, affecting both spillover and edge effects. One hypothesis is that individuals within FPAs will present reduced home range size relative to individuals in fished areas. This pattern can be driven by demographic selection (e.g. fishing of individuals with large home ranges leaving the FPAs), improved habitat requiring less foraging movements, or behavioural changes associated with reduced fishing threats. To test the relationship between home range size and protection, we compiled 1143 individual‐level home range sizes based on acoustic tracking, covering 17 species from 11 FPAs in 7 countries, with information on distance from FPA borders. A dichotomic analysis (in/out of FPAs) did not support a significant change in the home range size between FPAs and fished areas. However, continuous analysis across the FPA borders demonstrated reduced home range size within the FPAs. We did not find an effect of FPA age or size on this pattern. While we cannot pinpoint the underlying mechanism for the pattern revealed, we suggest behavioural changes as the main driver for reduced home range within FPAs. This mechanism will lead to more resident populations within FPAs, reducing fishing mortality within FPAs yet limiting spillover benefits to adjacent fisheries.

Mesophotic coral ecosystems are characterised by the presence of photosynthetic scleractinian corals despite the decreasing amounts of light available with depth. To better understand physiological strategies across a broad depth gradient, we studied the biological trait responses of Pocillopora cf. verrucosa from 6 to 60 m depth and Pachyseris “speciosa” spp. from 20 to 90 m depth at four islands of French Polynesia. Specifically, we characterised associated Symbiodiniaceae communities, photophysiological traits (Symbiodiniaceae density and chlorophyll concentrations), micro-morphology and trophic plasticity (autotrophy vs heterotrophy inferred from stable isotopes). Our results showed that both taxa can live at mesophotic depths without significant genetic structuring in their generic Symbiodiniaceae communities, mainly composed of Cladocopium and Durusdinium. Yet, the prevalence of Symbiodiniaceae ITS2 profiles revealed location-based variations that sometimes interact with depth and highlight putative shallow- or depth-tolerant taxa. For both taxa, symbiont density and chlorophyll pigment concentrations increased with increasing depth. We also found a change in their skeletal micro-morphology with an increase in the inter-corallite distance for Pocillopora cf. verrucosa and a decrease in the height of septa for Pachyseris “speciosa” spp. with depth. Finally, we found no isotopic evidence of switching to a more heterotrophic diet as their primary energy source, although host–tissue δ¹³C ratios became more negative with depth in both corals. Overall, our findings show similarity (across the two species) and species-specific strategies (biological trait patterns with increasing depth) underlying the capacity of symbiotic scleractinian corals to live in low-light environments.

The present study examined the long-term, transactional associations between school bonding and delinquency among Japanese adolescents. Two hundred seventy-one students were recruited in seventh grade (Time 1; M age = 12.72, SD = 0.45, 50% girls) and followed up until eighth grade. Data were collected at two time points (December of the seventh grade and eighth grade). The results of the cross-lagged panel model showed that higher delinquency was associated with lower school bonding. On the other hand, school bonding was not associated with a decrease in delinquency. When gender differences were examined, an association was found between higher delinquent tendencies and fewer school bonding for both genders. School bonding was not associated with a decrease in delinquency for both genders. At seventh grade, a negative correlation between school bonding and delinquency was found only for girls, but not for boys. The results, along with future implications, are discussed from cultural and developmental perspectives. This study provided valuable insight into the relationship between school ties and delinquency among adolescents from non-Western cultures such as the Japanese culture. Comparing the results of this study with those of other cultures may support the idea of cultural diversity.

Using seawater for flushing toilets is a potential solution to reduce freshwater consumption in Guam, an island in the Western Pacific Region. However, elevated salinity levels from seawater can affect microbial treatment efficiency in wastewater plants. To study this effect, synthetic wastewater containing 30 mg/L of ammonium-nitrogen was used to evaluate the impact of various salinity levels on ammonium removal efficiency in a continuously operated polyvinyl-alcohol gel bead bioreactor. The bioreactor was incrementally exposed to salinity levels of 0%, 20%, 30%, 50%, 70%, 80%, and 100%, where 0% represented tap water salinity and 100% was equivalent to Guam’s seawater salinity. A recovery phase followed the 100% salinity exposure to assess any changes in treatment processes. The total operational period spanned 212 days. Between 0 and 30% salinity, the ammonium-nitrogen removal efficiency averaged 95.0%, indicating no inhibition of nitrification. However, at 50% salinity, the ammonium-nitrogen concentration began to decrease, and a trend that continued up to 80% salinity, resulting in over 60.0% removal efficiency. At 100% salinity, the removal efficiency rapidly dropped from 59.2% to 15.4% within ten days. When the bioreactor returned to 0% salinity, the removal efficiency quickly recovered to 93.7% within five days. This experiment identified 50% salinity as a critical threshold for nitrification efficiency, while 100% salinity was found to be unfavorable for nitrification.

Carica papaya (papaya) in Guam, USA may experience soft rot symptoms, often referred to as mushy canker disease. Disease symptoms first appear as expanding water-soaked dark-green stem lesions or leaf spotting with chlorotic halos. Defoliation at petiole-stem junctions and crown necrosis leads to plant death. Papaya diseases caused by Erwinia spp. are documented in nearby tropic regions such as the Northern Mariana Islands (Trujillo and Schroth 1982), the Philippines (Dela Cueva et al. 2017), Japan (Hanagasaki et al. 2020), and Indonesia (Suharjo et al., 2021). The pathogen was isolated from symptomatic papaya stem sections (cv. Red Lady) from a nursery at the University of Guam Agriculture and Life Sciences building in April 2023. Approximately 20% of seedlings collapsed from stem soft rot, with nearly all plants showing varying degrees of water-soaked lesions on leaves or stems. Stem tissue from lesion margins was excised, surface sterilized with 70% EtOH, and macerated in sterile water. Macerate was plated onto nutrient agar (NA) and incubated at 28°C, yielding colonies that were clear to white in color, smooth, circular and mucoid on NA plates for five suspect isolates (JGD231-235). Strains produced blue diffusible pigment on King’s B (KB) media, were Gram-negative rods, and exhibited swimming motility on semi-solid (0.5% agar) NA plates. Crown stab inoculation of ten papaya plants (cv. Red Lady) with isolates resulted in mushy canker symptoms within seven days, while negative control plants stabbed with a sterile probe remained asymptomatic. Koch’s postulates were fulfilled by drench-inoculating spontaneous rifampicin-resistant (100µg/ml) mutants, JGD233r and JGD235r, onto ten papaya plants (cv. Solo Sunrise). Nine days post-inoculation, bacterial strains were recovered from symptomatic stem tissue macerate plated on rifampicin (100µg/ml) NA and incubated at 28°C. No symptoms or bacterial cells were recovered from the tissue of negative control plants. Cell morphology, culture phenotypes, and disease symptoms suggested the isolates were Erwinia spp., and blue pigment production on KB further suggested E. papayae (Gardan et al. 2004). Partial 16S rDNA sequences of Guam strains JGD231-235 (sequenced using PCR forward primer 5' - AGAGTTTGATCMTGGCTCAG - 3' and reverse primer 5' - GGTTACCTTGTTACGACTT - 3', GENEWIZ (South Plainfield, NJ)) were deposited into GenBank (OR577627- 631). Highest NCBI BLAST results for all strains showed a 16S rDNA sequence identity of 98.17-98.91% with those of Erwinia sp. I-leaf (LC590218) and E. mallotivora BT-MARDI (HQ456230). A maximum likelihood phylogenetic tree based on concatenated partial atpD, infB, and rpoB sequences of strains JGD232 (PP669340, PP669346, PP669343), JGD233 (PP669341, PP669347, PP669344), and JGD235 (PP669342, PP669348, PP669345) (Brady et al. 2008) constructed using MEGA11 (Tamura et al. 2021) showed all strains formed a monophyletic group with Erwinia sp. I-leaf (Hanagasaki et al. 2020) and E. papayae NCPPB 4294T (Gardan et al. 2004), supported with 98% bootstrap. This note documents the first occurrence of E. papayae as a papaya pathogen in Guam. Papaya cultivation supports sustainable food security for Guam (Bevacqua and Sayama 2023), and Erwinia spp. pathogens threaten papaya on other Pacific islands like Hawaii. These findings convey the need for effective quarantine practices, local disease management, and further research on this pathogen.

Crustaceans are one of the most widespread and speciose groups of marine organisms, fulfilling multiple ecological roles in numerous ecosystems. On coral reefs, many crustacean species form associations with scleractinian corals. Although the Red Sea is considered a biodiversity hotspot, few studies examined the diversity of coral-associated crustacean communities to date. In this study, 460 decapod crustaceans were recovered from 67 coral colonies of the three branching genera Acropora, Pocillopora and Stylophora in the central Saudi Arabian Red Sea. Crabs and shrimps were morphologically identified to the lowest taxonomic level possible, and portions of the mitochondrial COI and 16S rRNA genes were amplified with the objective of assessing their diversity and phylogenetic relationships. Finally, patterns of co-occurrence were evaluated to investigate the presence of species-specific symbiotic epifauna on different host corals. Overall, we recovered four families, five genera, and nine species of Red Sea crabs, nested into 11 molecular clades, and two families, eight genera and 11 species of shrimps, grouped within 12 lineages. Crabs of the species Trapezia tigrina were found to be exclusively associated with Pocillopora corals, while Tetralia crabs and the shrimps Jocaste japonica and Harpilius lutescens only occurred on Acropora colonies, providing evidence that potential loss of host corals due to local and global impacts could lead to consequent shifts in the symbiotic communities on reefs and to the loss of certain associated taxa. This study represents an advancement towards the understanding and molecular characterization of coral-associated benthic communities in the Red Sea and lays the ground for further research assessing the patterns of biodiversity, evolution, and ecological preferences of these organisms in the area.

Patterns of cohort decline are key demographic traits that provide a unique temporal perspective vital to understanding population dynamics. The discovery of multidecadal lifespans in tropical surgeonfishes in the 1990s created a paradigm shift to the notion that they are highly vulnerable species with low population recovery rates; however, research into the mortality patterns of surgeonfishes (Acanthuridae) has been sparse until recently. Recent studies on this family have demonstrated an unusual (possibly unique), two‐phase pattern of adult catch‐at‐age, whereby there is a population‐level shift from higher‐than‐expected rates of decline early in life to lower‐than‐expected decline rates for the remainder of the lifespan. To examine the geographic and phylogenetic ubiquity of this pattern, we compiled age‐based information from demographic samples of 70 populations of 25 tropical species spanning the Indo‐Central Pacific and Central‐Western Atlantic. Overall, we found that 79% of populations exhibited strong biphasic patterns, including 88% of populations across the Indo‐Central Pacific. By accounting for empirical relationships instead of using linear catch curves or classical assumptions of natural population decay based on lifespan, we demonstrate that surgeonfishes have turnover times that are two to four times faster than previously believed. Faster turnover times may suggest a higher level of sustainability for surgeonfish fisheries throughout the global tropics than previously estimated.

Background The demand for Senna alata Linn-based products is increasing due to their well-known therapeutic properties for treating various diseases, such as typhus, herpes, eczema, constipation, diarrhoea, gastroenteritis, and fungal skin diseases. Objective This study aims to compare the total yield of the extract, bioactive compounds, and antioxidant activity of S. alata leaves using various extraction methods. Method Extractions were performed using conventional maceration, Soxhlet, and non-conventional Subcritical Carbon Dioxide Soxhlet (SCDS) methods. The antioxidant properties of the leaf extracts were determined by the DPPH radical scavenging activities. Results Conventional methods yield higher percentages of extracts than SCDS, ranging from 1.20% to 25.14%. Soxhlet extraction with methanol showed the highest yields (25.14%) compared to hexane extraction (11.24%), indicating the solvent's influence on extraction efficiency. The effect of the sample-to-soaking solvent ratio on the extracted yield varied from 1.20 to 2.45% in the SCDS method. GCMS analysis showed the presence of 18 compounds, with phytol acetate, dihydroactinidiolide, and hexadecenoic acid methyl ester being the dominant ones. The DPPH assay shows that the extracts have in vitro antioxidant activity. The SCDS extract with methanol as a solvent had the highest IC50 value (0.693 ± 0.1725 mg/mL), while the extract with ethanol as a soaking solvent had the lowest (55.56 ± 2.29 mg/mL). Conclusion Although traditional techniques produced greater extract percentages, the SCDS method demonstrated potential for maintaining the bioactive components of S. alata leaf extracts. Overall, this research highlights the potential of the SCDS as an alternative extraction technique to maintain the quality of bioactive compounds in plant extracts.