Influence Of Wind Turbines On Mammalian Occupancy Patterns

Wind energy is among the most rapidly growing energy industries in the United States, with support for development coming from both state and federal governments. While the industry depicts an environmentally friendly image, the addition of infrastructure associated with wind farms alters landscapes in novel ways. Numerous studies have documented impacts wind turbines have on bird and bat mortality; however, far less attention has been directed towards responses of non-volant, terrestrial organisms. Mammalian mesocarnivores are model organisms to assess the alteration of communities surrounding wind turbines as they respond to addition of turbines and human activity, addition and improvement of roadways, and increases in turbine-induced carrion. In September 2011, I established a yearlong study surrounding the Central Plains Wind Facility in western Kansas to document patterns associated with the occupancy of terrestrial mammals within turbine and turbine-free habitats. I placed 34 scent-baited trail cameras among turbine and control habitats, with a randomly placed subset along roadways. Detection histories during 28-day survey periods and habitat covariates were analyzed with PRESENCE 5.5. Canis latrans and Vulpes velox were the most abundant mesocarnivores detected. Canis latrans had a higher probability of occupancy at the control area, while V. velox had higher probabilities of occupancy at the turbine area. Detection probabilities were impacted strongly by mean precipitation as well as between field and roadway locations for V. velox. Vulpes velox detection probabilities were conditional on C. latrans presence and detection, although the two species occupied sites independently

Sex-based differences in anti-predator response of crickets to chemical cues of a mammalian predator

Anti-predator behaviors like vigilance or hiding come at the expense of other fitness increasing behaviors such as foraging. To compensate for this trade-off, prey assess predation risk and modify the frequency of anti-predator behaviors according to the likelihood of the threat. In this study, we tested the ability of house crickets (Acheta domesticus) to indirectly assess predation risk via odors from a mammalian predator, Elliot\u27s short-tailed shrew (Blarina hylophaga). As natural differences in encounter rates and predation risk differs between sexes, we tested if male and female crickets perceive similar rates of predation risk from the presence of shrew odor measured via anti-predator behavioral response. Crickets were placed in enclosed, cardboard-lined chambers either treated with shrew odor or control, along with a food source. Time until foraging was measured for each individual and compared across treatment and sex. We found that in the presence of shrew odor, female crickets delayed foraging while males showed no response. These results suggest adult crickets can use chemical cues to detect mammalian predators. Furthermore, we demonstrate that female crickets associate greater predation risk from shrew predators than do male crickets, which are more stationary yet acoustically conspicuous. As predation risk potentially differs drastically for each sex, changes to the operational sex ratios of wild cricket populations could be influenced by the identity of the predator community

Dogs, Death, and Dietary Breadth: Insights into the Macroecology and Macroevolution of Canidae

The size, shape, and stability of a species’ dietary niche can both influence and reflect a variety of biological patterns, including species interactions, extinction risk, and ecosystem function. This is particularly apparent when dietary changes manifest at ecosystem and clade scales to profoundly affect macroecological and macroevolutionary trajectories. However, many studies exploring interactions, extinction, and ecosystem function rarely take into account dietary breadth across broad temporal and spatial scales, despite the fact that many ecological processes unfold over temporal and spatial scales that are beyond the scope of traditional ecology. This dissertation addresses this gap by testing the hypothesized drivers of two macroecological and macroevolutionary patterns using dietary niche breadth reconstructed from historical and paleontological canid specimens. Canid predators represent a model system for exploring broad patterns of ecology and evolution given their strong interspecific interactions coupled with a historical legacy of human-driven exterminations resulting in novel community dynamics. Additionally, North American canids offer a rich and diverse fossil history complete with iterative patterns of extinction and radiation used to describe macroevolutionary theory. I quantified dietary niche breadth for western North American canids via stable isotope analysis (SIA) and dental microwear texture analysis (DMTA) and applied these techniques across the spatial and temporal extent of canid distributions. Across space, I explored how mesopredator release has altered the dietary niche breadth of coyotes following the historical extirpation of gray wolves from the Pacific Northwest. Through time, I utilized the 33 million years of evolutionary history preserved in the North American canid fossil record to test the hypothesized link between dietary breadth and the ultimate extinction of canid lineages. In order to make more complete use of fossil, historical, and modern museum collections, which can contain fragmentary specimens, I also developed a novel approach to DMTA, devised to increase sample sizes while not biasing reconstructed dietary behaviors. I demonstrated that multiple facets along the cheek teeth in canids yield comparable microwear signals regardless of molar type or bite force (chapter 2). Thus scans from multiple molars can be combined to increase sample sizes among taxa with limited material. Looking across a latitudinal gradient along Western North America, I found that coyotes sympatric with wolves have reduced dietary niche breadth compared with coyotes sympatric with wolves. Furthermore, DMTA and SIA independently suggest released coyotes increased dietary plasticity following a reduction in scavenging behavior, previously facilitated by wolves (chapter 3). Extinction risk has been hypothesized to be positively correlated with dietary specialization, known as the macroevolutionary ratchet. The fossil record of canids has revealed iterative ratchets as multiple clades evolved towards hypercarnivory followed by rapid lineage extinctions. Morphological traits previously used to describe the macroevolutionary ratchet in canid evolution, however, are unable to capture the dietary breadth of a species. I found morphological traits were inferior to DMTA parameters at explaining extinction risk. Counter to expectations, I observed a positive correlation between specialization and lineage duration and that specialization was not correlated with traditionally-used dietary categories, suggesting that overspecialization in diet alone did not drive iterative extinctions in canids. Outcomes of this dissertation offer direct hypotheses for management officials dealing with proliferating mesopredators and trophic restructuring today. Additionally, my temporal analysis advances our fundamental understanding of macroevolutionary ratchets, and will enable future community-level studies of how species interactions influenced past evolutionary trajectories

Outcomes of patients with perforated colon cancer:A systematic review

Introduction: Perforated colon cancer (PCC) is a distinct clinical entity with implications for treatment and prognosis, however data on PCC seems scarce. The aim of this systematic review is to provide a comprehensive overview of the recent literature on clinical outcomes of PCC. Materials and methods: A systematic literature search of MEDLINE (PubMed), Embase, Cochrane library and Google scholar was performed. Studies describing intentionally curative treatment for patients with PCC since 2010 were included. The main outcome measures consisted of short-term surgical complications and long-term oncological outcomes. Results: Eleven retrospective cohort studies were included, comprising a total of 2696 PCC patients. In these studies, various entities of PCC were defined. Comparative studies showed that PCC patients as compared to non-PCC patients have an increased risk of 30-day mortality (8–33% vs 3–5%), increased post-operative complications (33–56% vs 22–28%), worse overall survival (36–40% vs 48–65%) and worse disease-free survival (34–43% vs 50–73%). Two studies distinguished free-perforations from contained perforations, revealing that free-perforation is associated with significantly higher 30-day mortality (19–26% vs 0–10%), lower overall survival (24–28% vs 42–64%) and lower disease-free survival (15% vs 53%) as compared to contained perforations. Conclusion: Data on PCC is scarce, with various PCC entities defined in the studies included. Heterogeneity of the study population, definition of PCC and outcome measures made pooling of the data impossible. In general, perforation, particularly free perforation, seems to be associated with a substantial negative effect on outcomes in colon cancer patients undergoing surgery. Better definition and description of the types of perforation in future studies is essential, as outcomes seem to differ between types of PCC and might require different treatment strategies.</p

Is surgeon annual case volume related with intra and postoperative complications after ventral hernia repair?:Uni- and multivariate analysis of prospective registry-based data

Background Literature on a potential relationship between surgeon case volume and intra- or postoperative complications after ventral hernia repair remains scarce. Methods Patients who underwent ventral hernia repair between 2011 and 2023 were selected from the prospectively maintained French Hernia-Club Registry. Outcome variables were: intraoperative events, postoperative general complications, surgical site occurrences, surgical site infections, length of intensive care unit (ICU), and patient-reported scar bulging during follow-up. Surgeons' annual case volume was categorized as 1-5, 6-50, 51-100, 101-125, and &gt; 125 cases, and its association with outcome volume was evaluated using uni- and multivariable analyses. Results Over the study period, 199 titular or temporary members registered 15,332 ventral hernia repairs, including 7869 primary, 6173 incisional, and 212 parastomal hernia repairs. In univariate analysis, surgeons' annual case volume was significantly related with all the postoperative studied outcomes. After multivariate regression analysis, annual case volume remained significantly associated with intra-operative complications, postoperative general complications and length of ICU stay. A primary repair was independently associated with fewer intra- and post-operative complications. Conclusion In the present multivariable analysis of a large registry on ventral hernia repairs, higher surgeon annual case volume was significantly related with fewer postoperative general complications and a shorter length of stay, but not with fewer surgical site occurrences, nor with less patient-reported scar bulging. Factors in the surgeons' case mix such as the type of hernia have significant impact on complication rates

Local recurrence at the site of the Lone Star device through implantation of exfoliated cells during local excision for early rectal cancer:A case report

Introduction: Invasive procedures for colorectal cancer can cause iatrogenic tumor cell seeding. Implantation of these exfoliated cells in the surrounding tissue can result in locoregional cancer recurrence. This has been described in endoscopic procedures and major surgical resections, however recurrence in iatrogenic lesions of the anal canal during minimal invasive rectal surgery has not been shown in literature yet. This is the first reported case of recurrent rectal cancer that developed into an anal metastasis at the site where hooks of the Lone Star Retractor disrupted the epithelial lining of the anal canal during a local excision of early rectal cancer using TAMIS. Presentation of case: A 57 year old male was diagnosed with a high risk early stage rectal adenocarcinoma. He was treated with transanal minimally invasive surgery (TAMIS) with the use of a Lone Star retractor and he received subsequent chemo-radiotherapy. 23 months later the patient developed a bleeding mass bulging out of the anus. A true cut and incision biopsy was performed and the pathology report revealed localization of adenocarcinoma at the anal canal which was similar to the earlier diagnosed rectal carcinoma. The patient underwent an abdominal perineal resection and left-sided lymph node dissection. Discussion and conclusion: This shows that local recurrence through implantation of exfoliated tumor cells can occur in iatrogenic lesions of the anal canal not only in major but also in minimal invasive rectal surgery. Careful tissue handling and rectal washout may reduce the chance of this implantation metastasis.</p

Local recurrence at the site of the Lone Star device through implantation of exfoliated cells during local excision for early rectal cancer:A case report

Introduction: Invasive procedures for colorectal cancer can cause iatrogenic tumor cell seeding. Implantation of these exfoliated cells in the surrounding tissue can result in locoregional cancer recurrence. This has been described in endoscopic procedures and major surgical resections, however recurrence in iatrogenic lesions of the anal canal during minimal invasive rectal surgery has not been shown in literature yet. This is the first reported case of recurrent rectal cancer that developed into an anal metastasis at the site where hooks of the Lone Star Retractor disrupted the epithelial lining of the anal canal during a local excision of early rectal cancer using TAMIS. Presentation of case: A 57 year old male was diagnosed with a high risk early stage rectal adenocarcinoma. He was treated with transanal minimally invasive surgery (TAMIS) with the use of a Lone Star retractor and he received subsequent chemo-radiotherapy. 23 months later the patient developed a bleeding mass bulging out of the anus. A true cut and incision biopsy was performed and the pathology report revealed localization of adenocarcinoma at the anal canal which was similar to the earlier diagnosed rectal carcinoma. The patient underwent an abdominal perineal resection and left-sided lymph node dissection. Discussion and conclusion: This shows that local recurrence through implantation of exfoliated tumor cells can occur in iatrogenic lesions of the anal canal not only in major but also in minimal invasive rectal surgery. Careful tissue handling and rectal washout may reduce the chance of this implantation metastasis.</p

Usefulness of CT scan as part of an institutional protocol for proactive leakage management after low anterior resection for rectal cancer

Purpose: Highly selective fecal diversion after low anterior resection (LAR) for rectal cancer requires a strict postoperative protocol for early detection of anastomotic leakage (AL). The purpose of this study was to evaluate C-reactive protein (CRP)–based CT imaging in diagnosis and subsequent management of AL. Methods: All patients that underwent a CT scan for suspicion of AL after transanal total mesorectal excision for rectal cancer in a university center (2015–2020) were included. Outcome parameters were diagnostic yield of CT and timing of CT and subsequent intervention. Results: Forty-four out of 125 patients underwent CT (35%) with an overall median interval of 5 h (IQR 3–6) from CRP measurement. The anastomosis was diverted in 7/44 (16%). CT was conclusive or highly suspicious for AL in 23, with confirmed AL in all those patients (yield 52%), and was false-negative in one patient (sensitivity 96%). CT initiated subsequent intervention after median 6 h (IQR 3–25). There was no or minor suspicion of AL on imaging in all 20 patients without definitive diagnosis of AL. After CT imaging on day 2, AL was confirmed in 0/1, and these proportions were 6/6 for day 3, 7/10 for day 4, 2/4 for day 5, and 9/23 beyond day 5. Conclusion: In the setting of an institutional policy of highly selective fecal diversion and pro-active leakage management, the yield of selective CT imaging using predefined CRP cut-off values was 52% with a sensitivity of 96%, enabling timely and tailored intervention after a median of 6 h from imaging.</p