A firebreak placement model for optimizing biodiversity protection at landscape scale.

A solution approach is proposed to optimize the selection of landscape cells for inclusion in firebreaks. It involves linking spatially explicit information on a landscape's ecological values, historical ignition patterns and fire spread behavior. A firebreak placement optimization model is formulated that captures the tradeoff between the direct loss of biodiversity due to the elimination of vegetation in areas designated for placement of firebreaks and the protection provided by the firebreaks from losses due to future forest fires. The optimal solution generated by the model reduced expected losses from wildfires on a biodiversity combined index due to wildfires by 30% relative to a landscape without any treatment. It also reduced expected losses by 16% compared to a randomly chosen solution. These results suggest that biodiversity loss resulting from the removal of vegetation in areas where firebreaks are placed can be offset by the reduction in biodiversity loss due to the firebreaks' protective function.

Minor head injury transfers: Trends and outcomes.

BACKGROUND: Children with traumatic head injury are often transferred from community Emergency Departments (ED) to a Pediatric Emergency Department (PED). The primary objective of this study was to describe the outcomes of minor head injury (MHI) transfers to a PED. The secondary objective was to report Computed Tomography (CT) utilization rates for MHI. METHODS: We conducted a retrospective study of children aged ≤18 years transferred to our PED for MHI from 2013 to 2018. Patients with Glasgow Coma Scale (GCS) < 14, coagulopathies, history of brain mass/shunt and suspected non-accidental trauma were excluded. Data collected included demographics, interventions performed, and disposition. MHI risk stratification and clinically important traumatic brain injury (ciTBI) were defined per the Pediatric Emergency Care Applied Research Network (PECARN) head injury guidelines. Descriptive statistics were reported using general measures of frequency and central tendency. RESULTS: A total of 1078 children with MHI were analyzed based on eligibility criteria. The majority of patients were male (62%) and ≥ 2 years of age (69.3%). Subspecialist consultation (57.2%) and neuroimaging (27.4%) were the most commonly performed interventions in the PED. Only 14 children (1.3%) required neurosurgical intervention. One-third of the transferred patients required no additional work-up. Two-thirds of the patients (66.6%) were directly discharged from the PED. Though the total number of MHI transfers per year declined steadily during the study period (from 271/year to 119/year), CT head utilization remained relatively similar across the study years (60.3% to 70.8%). A higher proportion of children received CT in the ED when compared to the PED for low-risk (28.9% vs 15.8%) and intermediate-risk groups (42.8% vs 29.4%). CONCLUSIONS: The majority of pediatric MHI transfers are discharged home following a subspecialty consultation and/or neuroimaging. Despite guidelines and a low incidence of ciTBI, CT utilization remains high in the intermediate and low risk MHI groups, especially in the community settings. Targeted interventions are needed to reduce the potentially avoidable transfers and low-value performance of CT in children with MHI.

Exploring the multidimensional effects of human activity and land cover on fire occurrence for territorial planning.

The strong link between climate change and increased wildfire risk suggests a paradigm change on how humans must co-exist with fire and the environment. Different studies have demonstrated that human-induced fire ignitions can account for more than 90 % of forest fires, so human co-existence with wildfires requires informed decision making via preventive policies in order to minimize risk and adapt to new conditions. In this paper, we address the multidimensional effects of three groups of drivers (human activity, geographic and topographic, and land cover) that can be managed to assist in territorial planning under fire risk. We found critical factors of strong interactions with the potential to increase the likelihood of starting a fire. Our solution approach included the application of a Machine Learning method called Random Undersampling and Boosting (RUSBoost) to assess risk (fire occurrence probability), which was subsequently accompanied by a sensitivity analysis that revealed interactions of various levels of risk. The prediction performance of the proposed model was assessed using several statistical measures such as the Receiver Operating Characteristic curve (ROC) and the Area Under the Curve (AUC). The results confirmed the high accuracy of our model, with an AUC of 0.967 and an overall accuracy over test data of 93.01 % after applying a Bayesian approach for hyper-parameter optimization. The study area to test our solution approach comprised the entire geographical territory of central Chile.

Surgical approaches to the calcaneus and the sural nerve: There is no safe zone.

BACKGROUND: Sural nerve related symptoms following the extensile lateral approach to the calcaneus (ELA) and the sinus tarsi approach (STA) are a known postoperative complication despite awareness of the course the sural nerve. While the main trunk of the sural nerve and its location relative to the approaches have been previously described, the nerve gives rise to lateral calcaneal branches (LCBs) and an anastomotic branch (AB) that may be at risk of injury. The purpose of this study was to describe the course of the sural nerve, its LCBs and the AB in relation to the ELA and STA. METHODS: 17 cadaveric foot specimens were dissected, exposing the sural nerve, the LCBs and the AB. A line representing the ELA and STA incision was then created. It was noted if the line crossed the sural nerve trunk, any of the LCBs, and the AB, and at what distance they were crossed using the distal tip of the fibula as a reference. RESULTS: The sural nerve was identified in all specimens, and the main trunk was noted to cross the path of the ELA in no specimens and the path of the STA in 2 (12%) specimens. At least one LCB of the sural nerve was identified in all specimens. The ELA crossed the path of at least one LCB in 15 specimens (88%). An AB was present in 9 specimens (53%). If an AB was present, this was crossed by the STA in every instance. CONCLUSIONS: The ELA and the STA traverses the path of either the main trunk of the sural nerve, the LCBs, or the AB in the majority of specimens, potentially accounting for the presence of sural nerve postoperative symptoms regardless of the approach used.

[Assessment of moral competence of physicians]. / Índice C en médicos de dos centros hospitalarios chilenos según el test de competencia moral de Lind.

BACKGROUND: Moral competence (MC) in physicians is fundamental, given the increasing complexity of medicine. The "Moral Competence Test" (MCT © Lind) evaluates this feature and its indicator is the C Index (CI). AIM: To explore moral competence and its associated factors among physicians working in Chile. MATERIAL AND METHODS: The MCT was answered by 236 physicians from two medical centers who voluntarily participated in the study. Besides the test, participants completed an encrypted form giving information about gender, years in practice and post-graduate studies. RESULTS: The average CI value of the participants was 20,9. Post-graduate studies had a significant positive influence on CI. There was a significant decrease in CI, between 16 and 20 years of professional exercise. Gender and the area of post-graduate studies did not have a significant influence. CONCLUSIONS: The studied physicians showed a wide range of CI which was positively affected by the postgraduate studies performed. The years of professional practice had a negative influence. Expanding training opportunities during professional practice could have a positive effect on CM as measured by CI.

Anatomical Study of the Princeps Pollicis Artery Perforator Flap.

BACKGROUND: The volar aspect of the thumb often requires local flaps for reconstruction. This study characterizes perforators of the princeps pollicis artery (PPA) and evaluates the potential of a local propeller-type flap raised using these perforators for reconstruction of these defects. METHODS: Cadavers underwent whole-body lead-oxide injection and were then imaged using a 64-slice spiral computed tomographic scanner. The DICOM images were imported into Materialise's Interactive Medical Imaging Control System (Materialise, Belgium) for 3-dimensional reconstruction of the microvasculature. The number, length, caliber, and location of perforators arising from the PPA were determined and a plot was generated illustrating the relative distribution of perforators. RESULTS: A total of 16 PPA perforators were identified in the 8 specimen hands. Perforators had a mean (SD) diameter of 1.2 (0.4) mm and mean (SD) length of 8.9 (4.8) mm. The PPA perforators were consistently identified along the radial aspect of the thenar region. Seventy percent of all PPA perforators can be found over the distal 50% of the MC [20%-54%; mean (1SD)]. CONCLUSIONS: Perforators of the PPA were found in all hands and the average caliber and length of the perforators identified is sufficient for the creation of a local perforator flap. This, coupled with the mean location of these perforators, arising near the base of the thumb, confirms that a cutaneous flap from the thenar region can be raised based on this perforator as a propeller flap to obtain coverage of distal cutaneous defects of the thumb.

The invasive species Ulex europaeus (Fabaceae) shows high dynamism in a fragmented landscape of south-central Chile.

Ulex europaeus (gorse) is an invasive shrub deemed as one of the most invasive species in the world. U. europaeus is widely distributed in the south-central area of Chile, which is considered a world hotspot for biodiversity conservation. In addition to its negative effects on the biodiversity of natural ecosystems, U. europaeus is one of the most severe pests for agriculture and forestry. Despite its importance as an invasive species, U. europaeus has been little studied. Although information exists on the potential distribution of the species, the interaction of the invasion process with the spatial dynamic of the landscape and the landscape-scale factors that control the presence or absence of the species is still lacking. We studied the spatial and temporal dynamics of the landscape and how these relate to U. europaeus invasion in south-central Chile. We used supervised classification of satellite images to determine the spatial distribution of the species and other land covers for the years 1986 and 2003, analysing the transitions between the different land covers. We used logistic regression for modelling the increase, decrease and permanence of U. europaeus invasion considering landscape variables. Results showed that the species covers only around 1 % of the study area and showed a 42 % reduction in area for the studied period. However, U. europaeus was the cover type which presented the greatest dynamism in the landscape. We found a strong relationship between changes in land cover and the invasion process, especially connected with forest plantations of exotic species, which promotes the displacement of U. europaeus. The model of gorse cover increase presented the best performance, and the most important predictors were distance to seed source and landscape complexity index. Our model predicted high spread potential of U. europaeus in areas of high conservation value. We conclude that proper management for this invasive species must take into account the spatial dynamics of the landscape within the invaded area in order to address containment, control or mitigation of the invasion.

National Trends in Foot and Ankle Arthrodesis: 17-Year Analysis of the National Survey of Ambulatory Surgery and National Hospital Discharge Survey.

Foot and ankle arthrodesis reliably reduces pain and functional disability among patients with arthritis and deformity. Since its introduction in 1953, improvements in surgical technique have enhanced the outcomes and reduced complications. However, little is known regarding US national trends of foot and ankle arthrodesis. The present study sought to use the most recently available Centers for Disease Control and Prevention data to investigate changes in the usage of inpatient and ambulatory foot and ankle arthrodesis. Cases of foot and ankle arthrodesis were identified using the National Hospital Discharge Survey and National Survey of Ambulatory Surgery, and the data were analyzed for trends in demographics, treatment, and usage. From 1994 to 2006, the population-adjusted rates of foot and ankle arthrodeses increased by 146% (8.2/100,000 capita to 20.2/100,000 capita). The number of outpatient arthrodeses performed with arthroscopic assistance increased by 858%. The population-adjusted rate of outpatient and inpatient procedures increased by 415% and 17%, respectively. The gender-adjusted rates increased by 59% for males and 209% for females. The age-adjusted rates increased among patients >35 years old in both settings. The use of peripheral nerve blocks during ambulatory procedures increased from 3.3% to 10.1%. Private insurance was the largest compensator. In conclusion, the rate of foot and ankle arthrodesis increased dramatically from 1990 to 2007 using the most up-to-date publicly available data. Knowledge of these national practice patterns could aid policy-makers and surgeons in appropriately allocating healthcare resources to ensure quality patient care.

Equivalent impacts of logging and beaver activities on aboveground carbon stock loss in the southernmost forest on Earth.

The conservation of forest landscapes is crucial for global climate strategies, and the forest in Tierra del Fuego, located in Patagonia, represents the southernmost example on Earth. These ecosystems are critical for Chile's roadmap toward carbon neutrality. Unfortunately, these ecosystems have been impacted by logging and beaver activities. Currently, the precise contribution of each driver to forest cover and carbon stock loss remains insufficiently quantified, impeding effective policymaking and the implementation of strategies to safeguard and enhance carbon stocks in these ecosystems. In this study, we conducted an assessment of forest carbon stock loss resulting from both logging and beaver activities in Chilean Tierra del Fuego from 1986 to 2019. While beavers have received significant attention for their substantial contribution to forest cover loss (56.1% forest cover, ≈ 1.4 MtC), our findings suggest that logging has nearly equally contributed to carbon stock depletion (43.8% forest cover, ≈ 1.2 MtC). Consequently, the prevailing focus on beavers has obscured the ongoing logging-induced carbon stock loss. The implications of our study highlight the urgency for comprehensive consideration of both drivers in Chile's climate strategy to fulfill the country's mitigation commitments.

Widespread synchronous decline of Mediterranean-type forest driven by accelerated aridity.

Large-scale, abrupt ecosystem change in direct response to climate extremes is a critical but poorly documented phenomenon1. Yet, recent increases in climate-induced tree mortality raise concern that some forest ecosystems are on the brink of collapse across wide environmental gradients2,3. Here we assessed climatic and productivity trends across the world's five Mediterranean forest ecosystems from 2000 to 2021 and detected a large-scale, abrupt forest browning and productivity decline in Chile (>90% of the forest in <100 days), responding to a sustained, acute drought. The extreme dry and warm conditions in Chile, unprecedented in the recent history of all Mediterranean-type ecosystems, are akin to those projected to arise in the second half of the century4. Long-term recovery of this forest is uncertain given an ongoing decline in regional water balance. This dramatic plummet of forest productivity may be a spyglass to the future for other Mediterranean ecosystems.

Multiple ERK substrates execute single biological processes in Caenorhabditis elegans germ-line development.

RAS-extracellular signal regulated kinase (ERK) signaling governs multiple aspects of cell fate specification, cellular transitions, and growth by regulating downstream substrates through phosphorylation. Understanding how perturbations to the ERK signaling pathway lead to developmental disorders and cancer hinges critically on identification of the substrates. Yet, only a limited number of substrates have been identified that function in vivo to execute ERK-regulated processes. The Caenorhabditis elegans germ line utilizes the well-conserved RAS-ERK signaling pathway in multiple different contexts. Here, we present an integrated functional genomic approach that identified 30 ERK substrates, each of which functions to regulate one or more of seven distinct biological processes during C. elegans germ-line development. Our results provide evidence for three themes that underlie the robustness and specificity of biological outcomes controlled by ERK signaling in C. elegans that are likely relevant to ERK signaling in other organisms: (i) multiple diverse ERK substrates function to control each individual biological process; (ii) different combinations of substrates function to control distinct biological processes; and (iii) regulatory feedback loops between ERK and its substrates help reinforce or attenuate ERK activation. Substrates identified here have conserved orthologs in humans, suggesting that insights from these studies will contribute to our understanding of human diseases involving deregulated ERK activity.

[Euthanasia, assisted suicide, and the principle of double effect: a reply to Rodolfo Figueroa]. / Eutanasia, suicidio asistido y principio del doble efecto: réplica al profesor Rodolfo Figueroa.

The purpose of this paper is to defend the traditional application of the principle of double effect as a criterion for assessing the permissibility of actions that have as their common aim to end the suffering of seriously ill patients. According to this principle, euthanasia and physician-assisted suicide are always illicit acts, while the same is not said for other actions that bring about patient's death as a foreseen effect, namely, palliative treatments that hasten death or failure or interruption of life support. The reason for this difference is that, in the first two cases, the patient's death is intended as a means of pain relief; whereas, in the latter two, death is only a side effect of a medical act, an act justifiable if it is necessary to achieve a proportionate good. In a recent issue of this Journal, Professor Rodolfo Figueroa denied the soundness of the principle of double effect and maintained that all actions described above should be considered equivalent in law enforcement. Here, the author presents a reply to that argument, and also offers a justification of the afore said principle's core, that is, the moral and legal relevance of the distinction between intended effects and foreseen side effects.

Moving towards the ecological intensification of tree plantations.

The growing demand for timber and the boom in massive tree-planting programs could mean the spreading of mismanaged tree plantations worldwide. Here, we apply the concept of ecological intensification to forestry systems as a viable biodiversity-focused strategy that could be critical to develop productive, yet sustainable, tree plantations. Tree plantations can be highly productive if tree species are properly combined to complement their ecological functions. Simultaneously considering soil biodiversity and animal-mediated biocontrol will be critical to minimize the reliance on external inputs. Integrating genetic, functional, and demographic diversity across heterogeneous landscapes should improve resilience under climate change. Designing ecologically intensified plantations will mean breaking the timber productivity versus conservation dichotomy and assuring the maintenance of key ecosystem services at safe levels.

Outcomes of Surgically Treated Fifth Metatarsal Fractures in Major League Soccer Athletes.

BACKGROUND: Sports-related fractures of the fifth metatarsal are common in professional athletes. Data regarding outcomes of surgical management including refracture, complications, and return-to-play statistics are available for other professional American sports with a notable exception of soccer. PURPOSE: To quantify the burden of operative fifth metatarsal fractures in Major League Soccer (MLS) athletes, to compare outcomes as well as refracture and complication rates with other professional sports, to analyze factors that may contribute to treatment failure, and to report on return-to-play characteristics for affected players. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We searched all injuries in the prospectively collected HealtheAthlete database for MLS for operative fifth metatarsal fractures for seasons 2013 to 2017. Additional information regarding each fracture including demographics, treatment, postoperative course, and return-to-play statistics were compiled from HealtheAthlete and supplemented by teams' chief medical officers, coaches, trainers, and online sources. RESULTS: There were 21 fractures in 18 players during the study period. Mean time to radiographic healing was 8.5 weeks (n = 17). Mean time to return to play was 11.1 weeks (n = 19). Of 21 fractures, 20 (95%) players returned to sport. Of 18 players, 4 (22.2%) experienced refracture. Of 18 players, 5 (27.8%) and 2 (11.1%) reported previous stress injuries on the contralateral and ipsilateral limb, respectively. Player performance characteristics showed small declines in the first year of return that improved by the second year. CONCLUSION: MLS athletes who sustain a sports-related fifth metatarsal fracture can expect a high rate of return to sport with time to radiographic healing and return to play as well as risk of refracture similar to other professional cohorts.

Fire-induced loss of the world's most biodiverse forests in Latin America.

Fire plays a dominant role in deforestation, particularly in the tropics, but the relative extent of transformations and influence of fire frequency on eventual forest loss remain unclear. Here, we analyze the frequency of fire and its influence on postfire forest trajectories between 2001 and 2018. We account for ~1.1% of Latin American forests burnt in 2002-2003 (8,465,850 ha). Although 40.1% of forests (3,393,250 ha) burned only once, by 2018, ~48% of the evergreen forests converted to other, primarily grass-dominated uses. While greater fire frequency yielded more transformation, our results reveal the staggering impact of even a single fire. Increasing fire frequency imposes greater risks of irreversible forest loss, transforming forests into ecosystems increasingly vulnerable to degradation. Reversing this trend is indispensable to both mitigate and adapt to climate change globally. As climate change transforms fire regimes across the region, key actions are needed to conserve Latin American forests.

Outcomes following surgical management of inguinal-related groin pain in athletes: a case series.

To determine the outcomes of a limited surgical intervention, consisting of neurolysis, inguinal wall repair and/or adductor debridement of adhesions based on intraoperative findings. Retrospective case series. Outpatient orthopedic/general surgery clinic. Fifty-one athletes treated surgically for inguinal-related groin pain from 2009 to 2015. Limited surgical intervention, consisting of neurolysis, inguinal wall repair and/or adductor debridement based on intra-operative findings. Ability to return to sport at the same level, time to return to play. Fifty-one athletes were included in the study with an average follow-up of 4.42 years (range 2.02-7.01). The average age was 24.2 years (range 16-49) and consisted of 94.0% males and 6.0% females. Nerve entrapment was demonstrated in 96.2% of cases with involvement of the ilioinguinal in 92.5%, the iliohypogastric in 30.8% and the genitofemoral in 13.2%. Attenuation of the posterior inguinal wall was present and repaired in 79.3% of cases. Scar tissue was present around the adductor origin and required debridement in 56.7% of cases. Forty-nine (96.1%) athletes returned to sport at the same level of play at an average of 5.9 weeks. Two athletes required a revision surgery. High rates of return to sport were achieved after surgery for inguinal-related groin pain that addresses the varying pathology and associated nerve entrapment.

Landscape restoration in a mixed agricultural-forest catchment: Planning a buffer strip and hedgerow network in a Chilean biodiversity hotspot.

Guidance for large-scale restoration of natural or semi-natural linear vegetation elements that takes into account the need to maintain human livelihoods such as farming is often lacking. Focusing on a Chilean biodiversity hotspot, we assessed the landscape in terms of existing woody vegetation elements and proposed a buffer strip and hedgerow network. We used spatial analysis based on Google Earth imagery and QGIS, field surveys, seven guidelines linked to prioritization criteria and seedling availability in the region's nurseries, and estimated the budget for implementing the proposed network. The target landscapes require restoring 0.89 ha km-2 of woody buffer strips to meet Chilean law; 1.4 ha km-2 of new hedgerows is also proposed. The cost of restoration in this landscape is estimated in ca. USD 6900 per planted ha of buffer strips and hedgerows. Financial incentives, education, and professional training of farmers are identified as key issues to implement the suggested restoration actions.

[Association between wound size after open cholecystectomy with severity of iatrogenic biliary tract lesions]. / Efecto del tamaño de la incisión en la gravedad de la lesin de la vía biliar iatrogénica posterior a colecistectomía abierta.

BACKGROUND: Transoperative biliary tract injury during open or laparoscopic cholecystectomy is a catastrophic event associated with significant morbidity and mortality. Our objective was to determine if wound size during open cholecystectomy is associated with more complex biliary tract injuries. METHODS: Prospective cohort study performed between March 2006 and February 2007. Sixty-six patients with biliary tract injuries after open cholecystectomy were included. Wound size was analyzed. RESULTS: Sixty six patients were included, 70% were female with a median age of 44. Seventy four percent were treated for acute cholecystitis. Most participants were overweight or had various degrees of obesity. Biliary tract injuries were not recognized during the primary surgical procedure in 76% of cases. All patients with severe biliary tract injuries (Strasberg E-3 and E-4) had a wound size less than 10 cm in length. Wound size was associated with unrecognized injuries (p=0.000), as well as with injury severity (p=0.000). We were notable to demonstrate a statistically significant association between biliary tract injuries and elective or emergency surgical procedures and midline or subcostal surgical incision for cholecystectomy. CONCLUSIONS: Our findings suggest that minor surgical access during open cholecystectomy may constitute a risk factor since smaller incisions were associated with more severe biliary tract injuries and an inability to observe this damage during the surgical procedure. We suggest to adhere strictly to the guidelines of an adequate surgical exposure during open cholecystectomy to prevent biliary tract injuries.