The effects of bag style on muscle activity of the trapezius, erector spinae and latissimus dorsi during walking in female university students

© by The Author(s). This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License. (CC BY-NC-ND 3.0)Back pain is common in adolescents which has been associated with carrying a bag. However, there is little research examining the effects of bag style in female adolescents. The aim of the study was to investigate the effects of different bag conditions on muscle activity of the trapezius, erector spinae and latissimus dorsi muscles in female university students during walking. Twelve female university students walked on a treadmill for 5 minutes at 1.1 m/s during five conditions; control, 1 strapped rucksack, 2 strapped rucksack, ipsilateral shoulder strap and contralateral shoulder strap, each containing 10% bodyweight. Electromyography for the trapezius, erector spinae and latissimus dorsi was recorded for the last 30 s of each condition. Two-way ANOVA and paired t-tests were used to identify differences between right and left muscles and between bag conditions. Results showed that muscle activity of the left trapezius was significantly higher than the right trapezius during the 1 strap rucksack condition. For the left trapezius, the 2 strapped rucksack and the control condition had significantly lower muscle activity compared to the 1 strapped rucksack and the ipsilateral shoulder strap. For the left erector spinae muscle, there was significantly greater muscle activity when wearing the contralateral shoulder strap compared to the control. For the right erector spinae, significantly lower muscle activity was observed when wearing the 2 strapped rucksack compared to the ipsilateral shoulder strap and contralateral shoulder strap. There were no significant differences in muscle activity of the latissimus dorsi muscles between any of the bag conditions. These findings suggest that a two strapped rucksack should be used when carrying loads to reduce spinal muscle activity which may, in turn, reduce reports of back pain in female adolescentPeer reviewedFinal Published versio

Environmental concentrations of the selective serotonin reuptake inhibitor fluoxetine impact specific behaviors involved in reproduction, feeding and predator avoidance in the fish Pimephales promelas (fathead minnow)

AbstractPharmaceuticals and personal care products (PPCPs) have been found in surface waters worldwide, but little is understood of their effects on the wildlife that inhabit these waters. Fluoxetine (Prozac; Eli Lilly), a highly prescribed selective serotonin reuptake inhibitor (SSRI), is a commonly found PPCP in surface water. The purpose of this project was to determine if environmentally relevant concentrations of fluoxetine impact behavior that is important for population survival in native fish species, including reproduction, feeding and predator avoidance. Chronic 4-week exposures were conducted with doses ranging from 100ng/L to 100μg/L to cover a range of environmentally relevant concentrations up to higher concentrations comparable to other published studies with the same drug that have documented various physiological impacts. Pimephales promelas (fathead minnow), a species native to North America, was used as it conducts a range of specific mating behaviors and therefore serves as an excellent model of specific impacts on brain function. Fluoxetine concentrations as low as 1μg/L, a concentration that has been found in many freshwater environments, were found to significantly impact mating behavior, specifically nest building and defending in male fish. Males were also found to display aggression, isolation, and repetitive behaviors at higher concentrations. Female mating behavior was largely unaffected. In addition, predator avoidance behaviors in males and females were also impacted at 1μg/L. Feeding was impacted at 10μg/L and in the highest exposure (100μg/L), egg production was limited by deaths of females due to significant male aggressive behaviors in the first two weeks of exposure. Specific behavioral changes occurred at each concentration (most noticeably 1μg/L and 100μg/L) indicating a dose dependent effect that triggered different responses at lower exposures versus higher exposures or differential impacts of dose depending on brain region. Length of exposure also had an impact on aggressive behavior. Changes in hormone levels, indicating significant neuroendocrine changes, suggested as a mechanism of response in higher dose and acute studies, were not linked to changes in behaviors at the doses used in this study. This research provides detailed data on how exposures to fluoxetine impact specific fish behaviors and reproduction and that the effects are dose dependent

Diphenylchloronitroethane Insecticides

Insecticidal activity of chloronitroalkanes was predicted on the basis of structure-activity relationships. Two series of new bis(substituted-phenyl) chloronitroalkanes were synthesized and evaluated for insecticidal activity. The synthetic pathway proceeded through phenylnitroethanols and diphenylnitroethanes as intermediates. Final products were 1,1-bis (substituted-phenyl)-2-chloro-2-nitroethanes and 1,1-bis(substituted-phenyl)-2,2-dichloro-2-nitroethanes. Aromatic substituents were selected from alkyl, alkoxy, and halogen moieties. Following purifications and confirmation of structures, the compounds were bioassayed against insects. The two series were compared for potency, as were various combinations of X and Y substituents. Adult female house flies (Musca domestica), mosquito larvae (Aedes aegypti), western corn rootworm (Diabrotica virgifera virgifera) and German cockroach (Blattellagermanica) have been tested. In general, the mono-chloro series is more toxic than the di-chloro series. Five of the mono-chloro analogs are 8-10 times more potent than pyrethrins and 6-7 times more toxic than methoxychlor to the house fly

Further Characterization of the Mitigation of Radiation Lethality by Protective Wounding

There continues to be a major effort in the United States to develop mitigators for the treatment of mass casualties that received high-intensity acute ionizing radiation exposures from the detonation of an improvised nuclear device during a radiological terrorist attack. The ideal countermeasure should be effective when administered after exposure, and over a wide range of absorbed doses. We have previously shown that the administration of a subcutaneous incision of a defined length, if administered within minutes after irradiation, protected young adult female C57BL/6 mice against radiation-induced lethality, and increased survival after total-body exposure to an LD50/30 X-ray dose from 50% to over 90%. We refer to this approach as "protective wounding". In this article, we report on our efforts to further optimize, characterize and demonstrate the validity of the protective wounding response by comparing the response of female and male mice, varying the radiation dose, the size of the wound, and the timing of wounding with respect to administration of the radiation dose. Both male and female mice that received a subcutaneous incision after irradiation were significantly protected from radiation lethality. We observed that the extent of protection against lethality after an LD50/30 X-ray dose was independent of the size of the subcutaneous cut, and that a 3 mm subcutaneous incision is effective at enhancing the survival of mice exposed to a broad range of radiation doses (LD15-LD100). Over the range of 6.2-6.7 Gy, the increase in survival observed in mice that received an incision was associated with an enhanced recovery of hematopoiesis. The enhanced rate of recovery of hematopoiesis was preceded by an increase in the production of a select group of cytokines. Thus, a thorough knowledge of the timing of the cytokine cascade after wounding could aid in the development of novel pharmacological radiation countermeasures that can be administered several days after the actual radiation exposure

the Reproductive Priming Effect Revisited: Mate Poaching, Mate Copying, Or Both?.

According to the reproductive priming effect, an individual who enters into a romantic relationship tends to see an increase in admirers. To further understand the mechanisms underlying this effect and its relationship with mate poaching and copying, 560 undergraduates were asked to report their experiences of being a romantic target (i.e., experiencing more admirers when in a new relationship) or an admirer (having greater attraction for someone in a relationship). Over two thirds of respondents noticed this increase in admirers, and approximately half reported being more attracted to a person who recently entered a new relationship. Many of the responses indicated that this increased interest was a result of “jealousy” and reported that they wanted what they couldn\u27t have. Behavioral changes were varied and correlated only weakly with the effect (both as admirer and target), which suggests that the attraction is mainly due to the target’s relationship status. Men were found to be seeking out other opportunities when in a new relationship, indicating a unique mating strategy

Special issue editorial : The Festival of OCIES 2020

No abstract available

Informed Cannabis Policies on Canadian Campuses: Toward the Protection of Youth and Young Adults

Introduction: The legalization of cannabis across Canada in October 2018 introduced issues including regulation at different levels, public and individual education, and discussions about cannabis product safety. We aimed to discuss ineffective and effective cannabis use policy on campuses and associated public areas, given the known short-term and long-term effects pertaining to its neurologic, pulmonary, and purported medicinal effects. Cannabis interferes with many of the body’s basic and executive (higher-level) functions. It is also associated with long-term harmful effects when chronically used. The purpose of this paper is to review and further discuss the responsibility local governments and educational institutions have for creating policies and regulations around cannabis use, particularly within post-secondary institutions, and for implementing educational strategies to promote public knowledge of cannabis. Methods: Peer-reviewed articles published in the last 10 years were searched for through the MEDLINE database. In addition, national and local health-related websites discussing cannabis policies were reviewed and collated. Expert opinions were also sought out to provide further information and resources. Results: 31 peer-reviewed articles and 12 professional websites were retrieved and reviewed. Correspondences with individual experts aware of and involved with campus cannabis policies also provided relevant resources and data used in this document. Conclusion: Smoke-free campus policies create the best health outcomes for the campus population. As well, creating effective and properly regulated policies and prioritizing public education is pertinent especially on universities where the population demographic is relatively young

Supermassive black holes in UCDs formed from the nuclei of disrupted galaxies

We use the hydrodynamic EAGLE simulation to predict the numbers and masses of supermassive black holes in stripped nuclei and compare these to confirmed measurements of black holes in observed UCDs. We find that black holes in stripped nuclei are consistent with the numbers and masses of those in observed UCDs. Approximately 50 per cent of stripped nuclei with $M > 2 \times 10^6 M_\odot$ should contain supermassive black holes. We further calculate a mass elevation ratio, $\Psi$ of the population of simulated stripped nuclei of $\Psi_{sim} = 1.51^{+0.06}_{-0.04}$ for $M > 10^7 M_\odot$ stripped nuclei, consistent with that of observed UCDs which have $\Psi_{obs} = 1.7 \pm 0.2$ above $M > 10^7 M_\odot$. We also find that the mass elevation ratios of stripped nuclei with supermassive black holes can explain the observed number of UCDs with elevated mass-to-light ratios. Finally, we predict the relative number of massive black holes in stripped nuclei and galaxy nuclei and find that stripped nuclei should increase the number of black holes in galaxy clusters by 30-100 per cent, depending on the black hole occupation fraction of low-mass galaxies. We conclude that the population of supermassive black holes in UCDs represents a large and unaccounted-for portion of supermassive black holes in galaxy clusters.Comment: 14 pages, Submitted to MNRA