Maine Maritime Academy

Ascophyllum nodosum (rockweed) is a dominant, canopy-forming seaweed found on intertidal rocky shores in the North Atlantic. Commercial uses for agriculture and food additives have supported industrial-scale harvesting by multiple countries in both the North American and European portions of its range. Rockweed removal changes the three-dimensional structure of the intertidal ecosystem, altering the characteristics of light, temperature, and wave energy for the benthic community. The potential for community impacts could be considerable. We conducted a three-year Before-After-Control-Impact (BACI) study to quantify how partial canopy removal affects the sessile benthic community along the coast of Maine (USA), where harvest regulations are more conservative than those found in all other countries. Using 22, marked, 16 m2 plots, we measured rockweed canopy height, biomass, and sessile taxa composition before and for two years after industrial harvest conducted by commercial partners. Presence and abundance models showed limited taxon-specific responses. While most benthic taxa were similar between control and impact sites, a few algae and invertebrates showed temporary reductions in line with changes in rockweed biomass, canopy height, or treatment category. Crustose red algae, on the other hand, exhibited somewhat higher abundance in harvested plots. Overall, the sessile community demonstrated stability after a single-event rockweed harvest. These results suggest that the current conservative commercial harvesting practices in Maine have limited short-term impacts on rockweed-associated benthic assemblages. Without the addition of other stressors, these practices would not be expected to lead to long-term changes in the benthic community.

Background/Objectives: Klebsiella pneumoniae is an opportunistic pathogen increasingly resistant to carbapenems and broad-spectrum antibiotics, complicating timely infection management. In critical cases like septic shock, where initiating effective antibiotics within 3 h improves survival, culture-based resistance testing is often too slow. This study evaluates machine learning (ML) algorithms for faster antimicrobial resistance prediction than conventional methods. Methods: In this retrospective study, antibiogram results of 607 Klebsiella pneumoniae isolates collected between 2017 and 2024 were combined with demographic and clinical information of the patients from whom the isolates were obtained. Four different ML algorithms, namely Decision Tree (DT), Support Vector Classifier (SVC), K-Nearest Neighbors (KNN) and Random Forest (RF), were applied to classify the resistance status for 22 antibiotics. Model performances were evaluated using accuracy, precision, recall, F-score, AUC and feature importance metrics. Results: The RF model showed the highest overall performance in accurately predicting resistance to 22 antibiotics, achieving an average AUC value of 0.96. In particular, it predicted resistance to treatment-critical antibiotics such as Ertapenem (100%), Imipenem (93%) and Meropenem (95%) with high accuracy. Conclusions: ML models, especially RF, offer a powerful tool for rapid antibiotic resistance prediction, supporting accurate empirical treatment decisions and antimicrobial stewardship.

This study employed an enhanced Photovoice method with data collection via ESRI Survey123 by integrating drone imagery and smartphone-produced photos, both taken by resident participants, to capture local perspectives to address tourism vulnerability and resilience in rural Indonesia. Two questions framed the study: How do communities perceive the vulnerabilities of tourism in their villages, and how do communities perceive their capacities? Participants from three tourism villages participated in the project by engaging in critical reflexive dialogues to reveal the meanings behind the photos, tourism vulnerabilities, and opportunities for enacting change. The findings revealed vulnerabilities and capacities leverageable to enhance tourism resilience in the villages. This novel methodology is highly effective for tourism disaster research in uncovering place-based insights, including vulnerabilities and opportunities, and building adaptive capacity and tourism resilience in less developed countries.

BACKGROUND:Patients undergoing Tc-99m MIBI myocardial perfusion scintigraphy (MPS) temporarily act as external photon sources, creating short-term radiation exposure to staff and accompanying persons. Quantitative real-patient data describing multiregional and multi-distance dose-rate behavior under dual-injection protocols remain limited. PURPOSE:To characterize patient-emitted radiation following dual-injection Tc-99m MIBI MPS and to estimate cumulative doses for realistic occupational and public-contact scenarios. METHODS:Ambient dose equivalent rates (μSv/h) were measured at four anatomical levels (head, thorax, abdomen, pelvis) and five distances (25-200 cm) at three post-stress time points. Distance dependence was evaluated using power-law regression, and temporal clearance at 100 cm was modeled mono-exponentially to derive region-specific effective half-lives. Scenario-based cumulative doses were calculated using both median (typical) and 95th percentile (conservative) dose rates. RESULTS:Dose rates decreased consistently with distance in all regions, with excellent regression fits (R2 ≥ 0.995) and empirical attenuation exponents of 0.53-0.76, consistent with extended-source behavior. Effective half-lives ranged from 4.65 to 5.69 h. Scenario-based cumulative exposures remained in the microsievert range, including ≤1.14 μSv for typical technologist contact and ≤9.69 μSv for conservative prolonged caregiver proximity. CONCLUSION:Dual-injection Tc-99m MIBI MPS results in very low external radiation exposure to staff and accompanying persons. Measured doses are far below regulatory constraints, supporting the adequacy of routine ALARA-based clinical practice without additional restrictions.

Introduction/objective: Patients undergoing diagnostic nuclear medicine procedures temporarily become sources of external radiation, potentially contributing to exposure of staff, accompanying persons, and other patients. This study aimed to evaluate activity-normalized survey-meter readings around patients undergoing routine 99(m)Tc-pertechnetate thyroid scintigraphy as a function of distance, anatomical level, and post-injection measurement time under real clinical conditions. Methods: A prospective observational study was conducted in eight patients. Free-in-air survey-meter readings were obtained using a NEB.211 dose-rate meter equipped with an energy-compensated Geiger-M & uuml;ller detector. Measurements were performed at four anatomical levels - head, thorax, abdomen, and pelvis - and five distances - 25, 50, 100, 150, and 200 cm - on three post-injection measurement occasions. Because measurement timing varied under routine workflow conditions, analyses were based on recorded actual times, with mean post-injection times of 19.6 +/- 14.4 min, 54.4 +/- 17.1 min, and 91.5 +/- 14.8 min. Readings were normalized to administered activity and interpreted as comparative survey-meter readings rather than calibrated H*(10) or Hp(10) dose-equivalent quantities. The distance-reading relationship was evaluated using log-log regression. Results: Activity-normalized survey-meter readings decreased consistently with increasing distance at all anatomical levels and across all three measurement occasions. Log-log regression demonstrated a strong inverse relationship between distance and activity-normalized readings, with empirical distance exponents ranging from-0.746 to-0.975 and corresponding R2 values ranging from 0.993-0.999. Abdominal and thoracic levels generally showed higher readings than head and pelvic levels, whereas temporal changes within the observed interval were modest compared with the distance effect. Discussion: The findings indicate that the patient-related radiation field under routine clinical conditions is strongly distance dependent and influenced by anatomical measurement level. Because the instrument did not have a traceable H*(10) calibration certificate, the results should be interpreted as comparative activity-normalized survey-meter data rather than absolute ambient dose-equivalent measurements. Conclusion: Increasing distance was the dominant practical factor for reducing measured patient-related radiation levels around patients undergoing 99mTc-pertechnetate thyroid scintigraphy. These findings support simple distance-based workflow optimization measures in nuclear medicine departments.