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The Antarctic photopsychrophile, Chlamydomonas priscui UWO241, is adapted to extreme environmental conditions, including permanent low temperatures, high salt, and shade. During long-term exposure to this extreme habitat, UWO241 appears to have lost several short-term mechanisms in favor of constitutive protection against environmental stress. This study investigated the physiological and growth responses of UWO241 to high-light conditions, evaluating the impacts of long-term acclimation to high light, low temperature, and high salinity on its ability to manage short-term photoinhibition. We found that UWO241 significantly increased its growth rate and photosynthetic activity at growth irradiances far exceeding native light conditions. Furthermore, UWO241 exhibited robust protection against short-term photoinhibition, particularly in photosystem I. Lastly, pre-acclimation to high light or low temperatures, but not high salinity, enhanced photoinhibition tolerance. These findings extend our understanding of stress tolerance in extremophilic algae. In the past 2 decades, climate change-related increasing glacial stream flow has perturbed long-term stable conditions, which has been associated with lake level rise, the thinning of ice covers, and the expansion of ice-free perimeters, leading to perturbations in light and salinity conditions. Our findings have implications for phytoplankton survival and the response to change scenarios in the light-limited environment of Antarctic ice-covered lakes.

Objectives: This study aimed to evaluate and compare local tolerability of investigational drug TV-46046 and reference drug Depo-subQ Provera 104, both containing medroxyprogesterone acetate (MPA) as an active ingredient. Study design: We conducted a randomized, crossover, single-center study. Twenty-seven healthy women aged 25 to 47 years at low risk of pregnancy received a subcutaneous injection of each of the four study drugs (120 mg/0.3 mL of TV-46046, 60 mg/0.3 mL of diluted TV-46046, 0.3 mL of TV-46046 placebo, and 104 mg/0.65 mL of Depo-subQ 104) in different quadrants of the abdomen. We assessed local tolerability by occurrence of injection site reactions (ISRs), as well as injection site pain and overall safety for at least 9 months postinjections. Results: Of a total of 108 study injections, three injections were partial due to needle blockage. We observed a total of 30 ISRs following 105 full-dose injections, including hypopigmentation (n = 24), bruising (n = 4), and atrophy/dimple (n = 2). Eleven cases of hypopigmentation occurred following 25 full-dose injections of undiluted TV-46046 (44.0%), six following 27 full-dose injections of diluted TV-46046 (22.2%), and seven following 26 full-dose injections of Depo-subQ 104 (26.9%). Hypopigmentations occurred on average 8 months postinjection. Injection pain was minimal and dissipated quickly after all four injections. Conclusions: Subcutaneous administration of MPA in a suspension formulation is associated with the delayed onset of hypopigmentation at the site of injection. Although not statistically significant, the rate of ISRs was over 60% higher for undiluted TV-46046 compared to Depo-subQ 104. This difference bears careful monitoring in future studies of TV-46046. Implications: From a safety standpoint, investigational drug TV-46046 is appropriate for further clinical testing as a 6-month contraceptive injectable. The previously underreported hypopigmentation associated with subcutaneous administration of MPA warrants further investigation and acceptability assessment among users of existing Depo-subQ 104 as well as careful monitoring of local tolerability of TV-46046 in future clinical trials. Trial registration: Registered at clinicaltrials.gov no: NCT02817464

The Antarctic photopsychrophile, Chlamydomonas priscui UWO241, is adapted to extreme environmental conditions, including permanent low temperatures, high salt, and shade. During long-term exposure to this extreme habitat, UWO241 appears to have lost several short-term mechanisms in favor of constitutive protection against environmental stress. This study investigated the physiological and growth responses of UWO241 to high-light conditions, evaluating the impacts of long-term acclimation to high light, low temperature, and high salinity on its ability to manage short-term photoinhibition. We found that UWO241 significantly increased its growth rate and photosynthetic activity at growth irradiances far exceeding native light conditions. Furthermore, UWO241 exhibited robust protection against short-term photoinhibition, particularly in photosystem I. Lastly, pre-acclimation to high light or low temperatures, but not high salinity, enhanced photoinhibition tolerance. These findings extend our understanding of stress tolerance in extremophilic algae. In the past 2 decades, climate change-related increasing glacial stream flow has perturbed long-term stable conditions, which has been associated with lake level rise, the thinning of ice covers, and the expansion of ice-free perimeters, leading to perturbations in light and salinity conditions. Our findings have implications for phytoplankton survival and the response to change scenarios in the light-limited environment of Antarctic ice-covered lakes. [ABSTRACT FROM AUTHOR]

Tigilanol tiglate is a novel small molecule approved as a veterinary pharmaceutical in Europe for intratumoural treatment of non-metastatic, non-resectable canine mast cell tumors. The drug has a “tumor agnostic” mode of action associated with induction of an acute inflammatory response at the treatment site, immune cell recruitment, and disruption of tumor vasculature. Consequently, tigilanol tiglate has potential in treating a range of tumor types in humans and companion animals. However, it is likely that species-specific dosing and concomitant medication protocols will be required, especially to manage the drug-induced acute inflammatory response at the treatment site. As an initial step in evaluating tigilanol tiglate for treating cutaneous tumors in horses, we developed an equine-specific protocol involving (a) a 30% reduction in intratumoural tigilanol tiglate dose rate compared to that used in dogs, and (b) a regime of concomitant medications to manage the drug-induced acute inflammatory response at the treatment site. Here we report a preliminary study in two horses using the protocol to treat (i) an aggressive fibroblastic sarcoid that had recurred following surgical excision and (ii) a fast-growing peri-ocular squamous cell carcinoma. Clinical response to tigilanol tiglate treatment in these cases was similar to that observed in canine and human patients. Localized inflammation and bruising developed rapidly at the treatment site with haemorrhagic necrosis of the tumor evident within 24 h. Slough of necrotic tumor mass occurred within 6–16 days followed by infill of the tissue defect and full re-epithelialisation of the treatment site with good functional outcome. Drug-induced inflammation and oedema at the treatment site were well controlled by the concomitant medications and largely resolved within 3 days, while the wound that formed following tumor slough healed uneventfully. Both patients displayed minor lethargy during the first 36 h after treatment and localized treatment-site discomfort was apparent over the first 3–5 days. There was no evidence of recurrence of the sarcoid at 93 days, or the squamous cell carcinoma at 189 days. The results from this study support continued development and evaluation of tigilanol tiglate as a potential future treatment option for cutaneous equine tumors.

Researchers suggest there is an increasing apathy in the study of natural history in academic settings and in the scientific community. However, most studies of environmental knowledge do not address knowledge of local flora and fauna; they are concerned with the knowledge of environmental issues or broad ecological knowledge. Ecoliteracy established local natural history as fundamental to environmental knowledge and seeks to determine the knowledge of local environments and factors associated with that knowledge. This study investigated ecoliteracy in Mississippi, determining knowledge of local flora and fauna of undergraduate and graduate students at the largest universities. Ecoliteracy levels in Mississippi were low. Students had a rudimentary knowledge of local flora and fauna, despite coursework in natural history. Students majoring in wildlife and fisheries and biology had more advanced knowledge of local flora and fauna than non-biology majors. Students were most knowledgeable of reptiles and amphibians, and least of fish and endangered species. The number of environmental courses taken and environmental sensitivity were positively correlated with ecoliteracy, and were strong predictors of ecoliteracy. Ecoliteracy was influenced by coursework and experience with degree programs including fieldwork. Natural history knowledge was deficient at Mississippi universities. Researchers suggest reintroducing coursework focused on ecoliteracy. (Contains 5 tables.)

This study tested two theoretical models of instructor credibility as a potential mediator between instructors' classroom communication behaviors (nonverbal immediacy, enthusiasm, and homophily) and students' intentions to persist in college. Participants included 570 undergraduate students from three institutions in the South-Central United States. Results of structural equation modeling provided greater support for the partial mediation model, in which nonverbal immediacy had both direct and indirect effects on students' intent to persist, though instructor enthusiasm and homophily were fully mediated by credibility. Overall, students' perceptions of these three instructor behaviors accounted for 56% of the variance in credibility and 43% of the variance in intent to persist. Furthermore, this model proved to be invariant across ethnic groups (Caucasian, African American, and Hispanic), suggesting that these instructor communication behaviors may contribute to positive outcomes for virtually all students, regardless of ethnicity. (Contains 3 tables and 6 figures.)

Teachers' cheating on high-stakes standardized tests is a serious problem for public schools. This study examined the influence of school tenure and policy attitudes about standardized testing on teachers' decisions to report a peer for violating testing protocol. In sum, 330 Texas school teachers responded to a survey that included a scenario depicting a teacher violating standardized testing protocol. Analysis of variance revealed that teachers with negative and moderate attitudes about standardized testing were less likely to report their peers than were those with positive attitudes about standardized testing. Implications of these findings include the important role that attitudes play in one's decision to report a peer for violating policy. The article concludes with limitations--which include the nonuse of random sampling and the reliance on a vignette rather than an actual situation--as well as directions for future research. (Contains 3 tables.)

This report uses meta-analysis to derive correlations between the variables of teacher immediacy, cognitive learning, and affective learning. A model was constructed such that the perception of teacher immediacy, a behavior, generates an intermediate outcome of affect, a motivation, which in turn increases cognitive learning outcome. The data across all the included investigations are consistent with that model. The results suggest that high levels of teacher immediacy function as a means of increasing the motivation of a student to learn, and that such motivation increases the cognitive mastery of material.

Presents a study in which experimental manipulation of combinations of nonverbal and verbal immediacy allowed researchers to more precisely test these causal links in relation to recall, learning loss, and affective learning. Notes that higher verbal immediacy in the experimental manipulations, when combined with higher and lower nonverbal immediacy, was not observed to produce greater cognitive learning. (SG)

Explores the possible relationship between students' expectations for teacher nonverbal immediacy and their enrollment in a distance-learning course. Finds that distance students expected less nonverbal immediacy from telecourse teachers than on-site students expected of their teachers; and that students with previous distance-learning experience had slightly higher expectancies than those with no experience. (SR)

Finds that undergraduate students more frequently attributed cause of breakups to situational factors than to the other person, and least frequently to self; and that persons who perceive they caused the breakup more frequently perceived they also initiated the breakup. Observes some hypothesized differences in reports for positive-tone, behavioral de-escalation, and negative identity management strategies. (SR)

Examines impact of variations in perceived intimacy on subjects' responses to a reasonably comprehensive list of compliance-gaining tactics. Questions 544 undergraduate students using an experimental recall method. Shows that situational variation in intimacy is associated with significant, nontrivial cross-situational differences in tactic selections. Notes that these effects were confirmed in a second situation. (PA)

Finds that when undergraduate student interactants had prior information about each other, state-receiver apprehension was positively related to uncertainty and both were negatively related to information-seeking and confirmation of relational predictions. Suggests that state-receiver apprehension may possibly lead to uncertainty. Develops a 13-item test of conversational state-receiver apprehension. (SR)

Investigates the relationship between general styles of communicating and more situation-specific conflict management styles. Finds substantial relationships between general communication styles and conflict management styles, as well as very substantial relationships between the style constructs and task attraction of supervisors. (SR)