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Agricultural workers such as migrant and seasonal farmworkers are a population uniquely vulnerable to the negative effects of climate-related disasters. The primary aim of this study was to assess how counties in eastern North Carolina (NC) incorporated best practices related to agricultural workers in emergency preparedness planning.
Methods
The authors conducted a quantitative content analysis of 47 emergency preparedness plans from 41 eastern NC counties between November 2022 and March 2023. The research team developed a codebook based on recommended best practices from the Centers for Disease Control and Prevention, Farmworker Advocacy Network, Federal Emergency Management Agency, and National Center for Farmworker Health. Best practices included having materials in Spanish language, mapping vulnerable populations, and garnering input from agricultural workers.
Results
Of the 47 plans evaluated, most lacked inclusion of agricultural workers in emergency preparedness planning. Furthermore, plans demonstrated few relevant best practices that address agricultural workers’ specific challenges in preparation for and recovery from climate-related disasters.
Conclusions
Public emergency preparedness plans in eastern NC rarely include mention of recommended best practices related to agricultural workers. Local emergency preparedness officials should consider collaboration with advocacy groups, community health workers, and federal emergency management agencies to build disaster resilience.
We aimed to determine if implementation of universal nasal decolonization with daily chlorhexidine bathing will decrease blood stream infections (BSI) in patients undergoing extracorporeal membrane oxygenation (ECMO).
Design:
Retrospective cohort study.
Setting:
Tertiary care facility.
Patients:
Patients placed on ECMO from January 1, 2017 to December 31, 2023.
Intervention:
Daily bathing with 4% chlorhexidine soap and universal mupirocin nasal decolonization were initiated for all ECMO patients May 2021. The primary outcome was rate of ECMO-attributable positive blood cultures. Zero-inflated Poisson regression analysis was performed to estimate rate ratios (RRs) for the association between decolonization with BSI rates.
Results:
A total of 776 patients met inclusion criteria during the study period, 425 (55%) preimplementation and 351 (45%) post-implementation. Following implementation of decolonization, the overall incidence rate of BSI increased nonsignificantly from 10.7 to 14.0 infections per 1000 ECMO days (aRR 1.09, 95% CI 0.74–1.59). For gram-positive cocci (GPC) pathogens, a nonsignificant 40% increased rate was observed in the post-implementation period (RR 1.40, 95% CI 0.89–2.21), due mostly to a significant increase in the crude rate of Enterococcus BSI (RR 1.89, 95% CI 1.01–3.55). Excluding Enterococcus resulted in a nonsignificant 28% decreased rate (aRR 0.72, 95% CI 0.39-1.36) due to a nonsignificant 55% decreased rate of MRSA (aRR 0.45, 95% CI 0.18–3.58).
Conclusions:
Implementation of a universal decolonization protocol did not significantly reduce rates of certain BSIs, including MRSA and other gram-positive pathogens. Although nonsignificant, reduction in BSI rates in this patient population has important implications on surveillance metrics, such as MRSA, and in the future, hospital-onset bacteremia.
Vaccines have revolutionised the field of medicine, eradicating and controlling many diseases. Recent pandemic vaccine successes have highlighted the accelerated pace of vaccine development and deployment. Leveraging this momentum, attention has shifted to cancer vaccines and personalised cancer vaccines, aimed at targeting individual tumour-specific abnormalities. The UK, now regarded for its vaccine capabilities, is an ideal nation for pioneering cancer vaccine trials. This article convened experts to share insights and approaches to navigate the challenges of cancer vaccine development with personalised or precision cancer vaccines, as well as fixed vaccines. Emphasising partnership and proactive strategies, this article outlines the ambition to harness national and local system capabilities in the UK; to work in collaboration with potential pharmaceutic partners; and to seize the opportunity to deliver the pace for rapid advances in cancer vaccine technology.
An “escape room” is a game requiring teamwork and problem-solving during which a series of puzzles are solved to escape a locked room. Various escape room activities have been designed for healthcare professionals, including internal medicine residents and nursing students (Anderson et al. Simulation & Gaming 2021; 52(1) 7-17; Rodríguez-Ferrer et al. BMC Med Educ 2022; 22:901; Khanna et al. Cureus 2021; 13 (9) e18314). Escape rooms provide an opportunity for social activity, an important component of resident wellness (Mari et al. BMC Med Educ 2019; 19(1):437). This abstract describes an escape room challenge designed and implemented at our psychiatry residency program quarterly wellness afternoon event, which is an afternoon session dedicated to resident wellness.
Objectives
The objective of this project was to design and implement an escape room challenge containing multiple game mechanics, including hidden roles, information asymmetry, acting, logical deduction, and spying. This activity was conducted to enhance bonding among residents while reinforcing knowledge in psychiatry.
Methods
We designed and implemented an escape room for 22 residents. Residents were divided into four teams each tasked with completing a sequence of puzzles to open the final lockbox. Two novel mechanics were added to the activity. Each team had a “clue holder” with clues to help solve all the puzzles. This team member had to conceal their identity because, if any of the other teams identified this person, the original winning team would have to give up the prize to the team that guessed the identity of this person. One member of each team was assigned a “spy” role whose mission was to make it hard for the clue holder to reveal all the clues. An anonymous post-activity survey was completed using Google Forms.
Results
The script was set in a fictional, abandoned psychiatric emergency room. The first task was a visual puzzle of a historic figure in psychiatry. The second activity involved residents guessing the psychotropic medication being acted out by another resident in the style of charades. The third activity required residents to apply developmental milestones to decode a combination lock. The fourth puzzle involved residents solving riddles by using information gathered from resident profiles on the residency program website.
Eleven (50%) residents completed the post-game survey. All residents answered true or very true that they enjoyed the game and that participation helped them better connect with their peers. Eight (73%) residents answered true or very true that they learned something from the activity.
Conclusions
An adapted escape room challenge is a novel wellness activity that enhance resident collegiality, teamwork, and bonding. All residents who completed the post-activity survey indicated that they enjoyed the activity and felt more connected to their peers afterwards.
To determine the effectiveness of active, upper-room, germicidal ultraviolet (GUV) devices in reducing bacterial contamination in patient rooms in air and on surfaces as a supplement to the central heating, ventilation, and air conditioning (HVAC) air handling unit (AHU) with MERV 14 filters and UV-C disinfection.
Methods:
This study was conducted in an academic medical center, burn intensive care unit (BICU), for 4 months in 2022. Room occupancy was monitored and recorded. In total, 402 preinstallation and postinstallation bacterial air and non–high-touch surface samples were obtained from 10 BICU patient rooms. Airborne particle counts were measured in the rooms, and bacterial air samples were obtained from the patient-room supply air vents and outdoor air, before and after the intervention. After preintervention samples were obtained, an active, upper-room, GUV air disinfection system was deployed in each of the patient rooms in the BICU.
Results:
The average levels of airborne bacteria of 395 CFU/m3 before GUV device installation and 37 CFU/m3 after installation indicated an 89% overall decrease (P < .0001). Levels of surface-borne bacteria were associated with a 69% decrease (P < .0001) after GUV device installation. Outdoor levels of airborne bacteria averaged 341 CFU/m3 in March before installation and 676 CFU/m3 in June after installation, but this increase was not significant (P = .517).
Conclusions:
Significant reductions in air and surface contamination occurred in all rooms and areas and were not associated with variations in outdoor air concentrations of bacteria. The significant decrease of surface bacteria is an unexpected benefit associated with in-room GUV air disinfection, which can potentially reduce overall bioburden.
From the safety inside vehicles, Knowsley Safari offers visitors a close-up encounter with captive olive baboons. As exiting vehicles may be contaminated with baboon stool, a comprehensive coprological inspection was conducted to address public health concerns. Baboon stools were obtained from vehicles, and sleeping areas, inclusive of video analysis of baboon–vehicle interactions. A purposely selected 4-day sampling period enabled comparative inspections of 2662 vehicles, with a total of 669 baboon stools examined (371 from vehicles and 298 from sleeping areas). As informed by our pilot study, front-line diagnostic methods were: QUIK-CHEK rapid diagnostic test (RDT) (Giardia and Cryptosporidium), Kato–Katz coproscopy (Trichuris) and charcoal culture (Strongyloides). Some 13.9% of vehicles were contaminated with baboon stool. Prevalence of giardiasis was 37.4% while cryptosporidiosis was <0.01%, however, an absence of faecal cysts by quality control coproscopy, alongside lower than the expected levels of Giardia-specific DNA, judged RDT results as misleading, grossly overestimating prevalence. Prevalence of trichuriasis was 48.0% and strongyloidiasis was 13.7%, a first report of Strongyloides fuelleborni in UK. We advise regular blanket administration(s) of anthelminthics to the colony, exploring pour-on formulations, thereafter, smaller-scale indicator surveys would be adequate.
Recruiting underrepresented people and communities in research is essential for generalizable findings. Ensuring representative participants can be particularly challenging for practice-level dissemination and implementation trials. Novel use of real-world data about practices and the communities they serve could promote more equitable and inclusive recruitment.
Methods:
We used a comprehensive primary care clinician and practice database, the Virginia All-Payers Claims Database, and the HealthLandscape Virginia mapping tool with community-level socio-ecological information to prospectively inform practice recruitment for a study to help primary care better screen and counsel for unhealthy alcohol use. Throughout recruitment, we measured how similar study practices were to primary care on average, mapped where practices’ patients lived, and iteratively adapted our recruitment strategies.
Results:
In response to practice and community data, we adapted our recruitment strategy three times; first leveraging relationships with residency graduates, then a health system and professional organization approach, followed by a community-targeted approach, and a concluding approach using all three approaches. We enrolled 76 practices whose patients live in 97.3% (1844 of 1907) of Virginia’s census tracts. Our overall patient sample had similar demographics to the state for race (21.7% vs 20.0% Black), ethnicity (9.5% vs 10.2% Hispanic), insurance status (6.4% vs 8.0% uninsured), and education (26.0% vs 32.5% high school graduate or less). Each practice recruitment approach uniquely included different communities and patients.
Discussion:
Data about primary care practices and the communities they serve can prospectively inform research recruitment of practices to yield more representative and inclusive patient cohorts for participation.
The aim of this review was to summarize current evidence from the United States on the effectiveness of practices and interventions for preventing, recognizing, and controlling occupationally acquired infectious diseases in Emergency Medical Service (EMS) clinicians.
Report and Methods:
PubMed, Embase, CINAHL, and SCOPUS were searched from January 1, 2006 through March 15, 2022 for studies in the United States that involved EMS clinicians and firefighters, reported on one or more workplace practices or interventions that prevented or controlled infectious diseases, and included outcome measures. Eleven (11) observational studies reported on infection prevention and control (IPC) practices providing evidence that hand hygiene, standard precautions, mandatory vaccine policies, and on-site vaccine clinics are effective. Less frequent handwashing (survey-weight adjusted odds ratio [OR] 4.20; 95% confidence interval [CI], 1.02 to 17.27) and less frequent hand hygiene after glove use (survey-weight adjusted OR 10.51; 95% CI, 2.54 to 43.45) were positively correlated with nasal colonization of Methicillin-resistant Staphylococcus aureus (MRSA). Lack of personal protective equipment (PPE) or PPE breach were correlated with higher severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seropositivity (unadjusted risk ratio [RR] 4.2; 95% CI, 1.03 to 17.22). Workers were more likely to be vaccinated against influenza if their employer offered the vaccine (unadjusted OR 3.3; 95% CI, 1.3 to 8.3). Active, targeted education modules for H1N1 influenza were effective at increasing vaccination rates and the success of on-site vaccine clinics.
Conclusions:
Evidence from the United States exists on the effectiveness of IPC practices in EMS clinicians, including hand hygiene, standard precautions, mandatory vaccine policies, and vaccine clinics. More research is needed on the effectiveness of PPE and vaccine acceptance.
Prior to the COVID-19 pandemic, our research group initiated a pediatric practice-based randomized trial for the treatment of childhood obesity in rural communities. Approximately 6 weeks into the originally planned 10-week enrollment period, the trial was forced to pause all study activity due to the COVID-19 pandemic. This pause necessitated a substantial revision in recruitment, enrollment, and other study methods in order to complete the trial using virtual procedures. This descriptive paper outlines methods used to recruit, enroll, and manage clinical trial participants with technology to obtain informed consent, obtain height and weight measurements by video, and maintain participant engagement throughout the duration of the trial.
Methods:
The study team reviewed the IRB records, protocol team meeting minutes and records, and surveyed the site teams to document the impact of the COVID-19 shift to virtual procedures on the study. The IRB approved study changes allowed for flexibility between clinical sites given variations in site resources, which was key to success of the implementation.
Results:
All study sites faced a variety of logistical challenges unique to their location yet successfully recruited the required number of patients for the trial. Ultimately, virtual procedures enhanced our ability to establish relationships with participants who were previously beyond our reach, but presented several challenges and required additional resources.
Conclusion:
Lessons learned from this study can assist other study groups in navigating challenges, especially when recruiting and implementing studies with rural and underserved populations or during challenging events like the pandemic.
Vaccination coverage for infants with CHD is unknown, yet these patients are at high risk for morbidity and mortality associated with vaccine-preventable illnesses. We determined vaccination rates for this population and identified predictors of undervaccination. We prospectively enrolled infants with CHD born between 1 January, 2012 and 31 December, 2015, seen in a single-centre cardiology clinic between 15 February, 2016 and 28 February, 2017. We assessed vaccination during the first year of life. Subjects who by age 1 year received all routine immunisations recommended during the first 6 months of life were considered fully vaccinated. We also evaluated influenza vaccination during subjects’ first eligible influenza season. We obtained immunisation histories from primary care providers and collected demographic and clinical data via a parent survey and chart review. We used multivariable logistic regression to identify predictors of undervaccination. Among 260 subjects, only 60% were fully vaccinated. Vaccination rates were lowest for influenza (64.6%), rotavirus (71.1%), and Haemophilus influenzae type b (79.3%). Cardiac surgery with cardiopulmonary bypass during the first year of life was associated with undervaccination (51.5% versus 76.4% fully vaccinated, adjusted odds ratio 2.1 [95% confidence interval 1.1–3.9]). Other predictors of undervaccination were out-of-state primary care (adjusted odds ratio 2.7 [1.5–4.9]), multiple comorbidities (≥2 versus 0–1, adjusted odds ratio 2.0 [1.1–3.6]), and hospitalisation for >25% of the first year of life (>25% versus ≤25%, adjusted odds ratio 2.1 [1.1–3.9]). Targeted quality improvement initiatives focused on improving vaccination coverage for these infants, especially surrounding cardiac surgery, are needed.
We observed an overall increase in the use of third- and fourth-generation cephalosporins after fluoroquinolone preauthorization was implemented. We examined the change in specific third- and fourth-generation cephalosporin use, and we sought to determine whether there was a consequent change in non-susceptibility of select Gram-negative bacterial isolates to these antibiotics.
Design:
Retrospective quasi-experimental study.
Setting:
Academic hospital.
Intervention:
Fluoroquinolone preauthorization was implemented in the hospital in October 2005. We used interrupted time series (ITS) Poisson regression models to examine trends in monthly rates of ceftriaxone, ceftazidime, and cefepime use and trends in yearly rates of nonsusceptible isolates (NSIs) of select Gram-negative bacteria before (1998–2004) and after (2006–2016) fluoroquinolone preauthorization was implemented.
Results:
Rates of use of ceftriaxone and cefepime increased after fluoroquinolone preauthorization was implemented (ceftriaxone RR, 1.002; 95% CI, 1.002–1.003; P < .0001; cefepime RR, 1.003; 95% CI, 1.001–1.004; P = .0006), but ceftazidime use continued to decline (RR, 0.991, 95% CI, 0.990–0.992; P < .0001). Rates of ceftazidime and cefepime NSIs of Pseudomonas aeruginosa (ceftazidime RR, 0.937; 95% CI, 0.910–0.965, P < .0001; cefepime RR, 0.937; 95% CI, 0.912–0.963; P < .0001) declined after fluoroquinolone preauthorization was implemented. Rates of ceftazidime and cefepime NSIs of Enterobacter cloacae (ceftazidime RR, 1.116; 95% CI, 1.078–1.154; P < .0001; cefepime RR, 1.198; 95% CI, 1.112–1.291; P < .0001) and cefepime NSI of Acinetobacter baumannii (RR, 1.169; 95% CI, 1.081–1.263; P < .0001) were increasing before fluoroquinolone preauthorization was implemented but became stable thereafter: E. cloacae (ceftazidime RR, 0.987; 95% CI, 0.948–1.028; P = .531; cefepime RR, 0.990; 95% CI, 0.962–1.018; P = .461) and A. baumannii (cefepime RR, 0.972; 95% CI, 0.939–1.006; P = .100).
Conclusions:
Fluoroquinolone preauthorization may increase use of unrestricted third- and fourth-generation cephalosporins; however, we did not observe increased antimicrobial resistance to these agents, especially among clinically important Gram-negative bacteria known for hospital-acquired infections.
Several decades of basic research support the neural basis of multiple memory systems. These systems are highly relevant to all health behaviors, since behaviors are learned from experience and require some form of memory process to retain learning and affect subsequent action. Research on the neuroscience of appetitive behaviors has rigorously studied motivational processes involved in behaviors such as drug use, diet, and sex. However, very little of this otherwise stellar research has attempted to integrate its findings with multiple memory system views that acknowledge the wide range of memory effects uncovered in several highly relevant basic research areas. Further, good explanatory theories of multiple memory systems studied mostly in addiction and in animal research have not yet been integrated with the vast knowledge base from human cognitive science. Moreover, most research on the epidemiology, prevention, or treatment of problems in appetitive behavior has not taken into account these basic research findings and has instead focused on theories and methods derived primarily from survey research. Yet, basic research areas from neuroscience and cognitive science are highly relevant to all areas of study of appetitive behavior, and the prevailing focus in prevention science on concepts derived from survey research may be channeled mostly by the training of investigators and disciplinary history. This chapter provides one example of how these disparate literatures from basic research might be integrated to advance our understanding of this class of behavior and derive new possibilities for intervention. It highlights examples of key findings supporting the need for a greater translational effort but also highlights large gaps in knowledge. Future research filling these gaps and others in the void between compelling research domains could substantially change and advance the study of addictions and all appetitive or habit-forming behaviors.
Due to concerns over increasing fluoroquinolone (FQ) resistance among gram-negative organisms, our stewardship program implemented a preauthorization use policy. The goal of this study was to assess the relationship between hospital FQ use and antibiotic resistance.
Design
Retrospective cohort.
Setting
Large academic medical center.
Methods
We performed a retrospective analysis of FQ susceptibility of hospital isolates for 5 common gram-negative bacteria: Acinetobacter spp., Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Primary endpoint was the change of FQ susceptibility. A Poisson regression model was used to calculate the rate of change between the preintervention period (1998–2005) and the postimplementation period (2006–2016).
Results
Large rates of decline of FQ susceptibility began in 1998, particularly among P. aeruginosa, Acinetobacter spp., and E. cloacae. Our FQ restriction policy improved FQ use from 173 days of therapy (DOT) per 1,000 patient days to <60 DOT per 1,000 patient days. Fluoroquinolone susceptibility increased for Acinetobacter spp. (rate ratio [RR], 1.038; 95% confidence interval [CI], 1.005–1.072), E. cloacae (RR, 1.028; 95% CI, 1.013–1.044), and P. aeruginosa (RR, 1.013; 95% CI, 1.006–1.020). No significant change in susceptibility was detected for K. pneumoniae (RR, 1.002; 95% CI, 0.996–1.008), and the susceptibility for E. coli continued to decline, although the decline was not as steep (RR, 0.981; 95% CI, 0.975–0.987).
Conclusions
A stewardship-driven FQ restriction program stopped overall declining FQ susceptibility rates for all species except E. coli. For 3 species (ie, Acinetobacter spp, E. cloacae, and P. aeruginosa), susceptibility rates improved after implementation, and this improvement has been sustained over a 10-year period.
There is a growing interest in using cognitive–behavioural therapy (CBT) with people who have Asperger syndrome and comorbid mental health problems.
Aims
To examine whether modified group CBT for clinically significant anxiety in an Asperger syndrome population is feasible and likely to be efficacious.
Method
Using a randomised assessor-blind trial, 52 individuals with Asperger syndrome were randomised into a treatment arm or a waiting-list control arm. After 24 weeks, those in the waiting-list control arm received treatment, while those initially randomised to treatment were followed up for 24 weeks.
Results
The conversion rate for this trial was high (1.6:1), while attrition was 13%. After 24 weeks, there was no significant difference between those randomised to the treatment arm compared with those randomised to the waiting-list control arm on the primary outcome measure, the Hamilton Rating Scale for Anxiety.
Conclusions
Trials of psychological therapies with this population are feasible. Larger definitive trials are now needed.
A controversy at the 2016 IUCN World Conservation Congress on the topic of closing domestic ivory markets (the 007, or so-called James Bond, motion) has given rise to a debate on IUCN's value proposition. A cross-section of authors who are engaged in IUCN but not employed by the organization, and with diverse perspectives and opinions, here argue for the importance of safeguarding and strengthening the unique technical and convening roles of IUCN, providing examples of what has and has not worked. Recommendations for protecting and enhancing IUCN's contribution to global conservation debates and policy formulation are given.
Clinical depression affects approximately 15% of community-dwelling older adults, of which half of these cases present in later life. Falls and depressive symptoms are thought to co-exist, while physical activity may protect an older adult from developing depressive symptoms. This study investigates the temporal relationships between depressive symptoms, falls, and participation in physical activities amongst older adults recently discharged following extended hospitalization.
Methods:
A prospective cohort study in which 311 older adults surveyed prior to hospital discharge were assessed monthly post-discharge for six months. N = 218 completed the six-month follow-up. Participants were recruited from hospitals in Melbourne, Australia. The survey instrument used was designed based on Fiske's behavioral model depicting onset and maintenance of depression. The baseline survey collected data on self-reported falls, physical activity levels, and depressive symptoms. The monthly follow-up surveys repeated measurement of these outcomes.
Results:
At any assessment point, falls were positively associated with depressive symptoms; depressive symptoms were negatively associated with physical activity levels; and, physical activity levels were negatively associated with falls. When compared with data in the subsequent assessment point, depressive symptoms were positively associated with falls reported over the next month (unadjusted OR: 1.20 (1.12, 1.28)), and physical activity levels were negatively associated with falls reported over the next month (unadjusted OR: 0.97 (0.96, 0.99) household and recreational), both indicating a temporal relationship.
Conclusion:
Falls, physical activity, and depressive symptoms were inter-associated, and depressive symptoms and low physical activity levels preceded falls. Clear strategies for management of these interconnected problems remain elusive.
Studies have found positive correlations between prenatal exposure to testosterone and masculinization of offspring traits, particularly among females. The present study sought to determine if physical or sexual activity by the mother during pregnancy was related to masculinized/defeminized offspring traits in adulthood. Data were obtained from a large sample of North American college students (offspring) and their mothers. Information about maternal activity levels during pregnancy were reported retrospectively by each mother. The offspring provided self-ratings of various sexually dimorphic traits. Several significant correlations were found. By and large, as maternal physical activity increased, feminine mannerisms decreased and masculine mannerisms increased in the offspring, particularly for females. Maternal physical activity was also associated with increased upper- and lower-body strength and especially with adult height among offspring. Sexual activity by the mother was only associated with upper-body strength and adult height, particularly of the female offspring. Several sexually dimorphic physical traits in offspring are associated with maternal activity levels during pregnancy. Prenatal testosterone is almost certainly involved. The associations could either reflect genetic influences (given that prenatal testosterone is highly heritable) or an effect of maternal testosterone being transferred to the developing fetus. More research is needed to assess the relative merit of these two possibilities.
The sea ice in McMurdo Sound, Antarctica, is extensively utilized for runways, travel, freight hauling and docking facilities. The safety and efficiency of these operations depend upon a better understanding of the sea-ice bearing strength.
Variations in shear and tensile strength, decreased thickness, salinity changes, internal deterioration and changes of the temperature gradient are all related to and dependent upon snow cover, ambient temperatures and solar radiation. During the austral summer of 1964–65, shear strength decreased from 9.8 kg./cm.2 in October to 6.3 kg./cm.2 in late January and then increased to 8.0 kg./cm2. by 10 February. The salinity of collected brine decreased from 125 p.p.t. in November to 43 p.p.t. in January. Thickness increased until mid-December, then decreased rapidly by bottom melting until break-out in February. In the Cape Armitage shoal area, thickness decreased from 2.5 m. in mid-December to 36 cm. in late January. Snow cover significantly affects the degree of internal deterioration and the amount of strength loss during the summer. Sea ice with more than 6 cm. snow cover is consistently stronger than unprotected ice and deterioration is less. Bearing strength of the sea ice is sufficient for most ordinary loads throughout the period of most extensive use.
A procedure is described for testing cored ice specimens under uniaxial tension. The procedure incorporates an end-capping system described by Cole and others (1985), two carpeted Synthane end caps, and extensometers mounted directly on the ice. Use of the procedure has resulted in a successful test rate of 75%
We analyzed the recent (< 25 yr) spread in New Hampshire, USA, of the exotic tree Kalopanax septemlobus, native to Asia. The invasion was likely initiated by a single tree planted ca. 1972. Our objective was to assess the viability of the invasion, especially in light of the small propagule size. We tallied, mapped, aged, and measured the height and growth of K. septemlobus individuals at two sites, the University of New Hampshire campus (UC) and Thompson Farm (TF), both in Durham. We found over 3,800 plants at UC and 270 at TF in < 120 ha (296 ac) total area. Plant age ranged from 0 to 22 yr, and UC plants were as far as 775 m (2,543 ft) from the purported parent tree. Annual height growth was comparable to midtolerant native trees. Plants occurred in both open and forested habitats, and the mean level of photosynthetically active radiation incident on understory plants was 4 to 6% of full sun. The large population size, shade tolerance, rapid height growth, and ability to sprout from damaged stems suggest potential for K. septemlobus to invade and persist in forests, the most common natural ecosystem in the northeastern United States. We further suggest that small propagule size, likely a single tree, has not prevented K. septemlobus from initiating a spatially extensive and vigorous population. Kalopanax septemlobus has been planted as an ornamental in the northeastern United States, and prevention of region-wide invasion might depend on removal of these trees, even when they occur as single individuals.