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Economic Co-Benefits of Nature-Based Carbon Removal Projects in the Brazilian Amazon
No full textMombak is a Brazil-based carbon removal startup with a mission to reforest the Amazon through the conversion of unproductive, low-yield farmland back into rainforest. Their business model relies heavily on the sale of carbon credits on the voluntary carbon market (VCM) to multi-national companies with net-zero targets. While carbon removal projects generally garner a price premium on the VCM as compared to carbon reduction projects, price levels among all offsets remain stubbornly low due both to lack of government policy intervention as well as the nascent and inefficient nature of the VCM. Nature-based solutions, as Mombak offers, additionally generate co-benefits which are of economic value to communities locally and abroad. Through a review of the most relevant economic valuation studies on the Amazon rainforest, this analysis seeks to answer what value added a Mombak carbon credit may generate beyond just its ability to sequester carbon. Our findings demonstrate that the value to society of a Mombak carbon credit far exceeds what is reflected by the VCM today and suggest that a price premium for a Mombak generated carbon credit is more than justified
Problemáticas: Multi-scalar, affective and performative politics of collective action among fishing cooperatives in Mexico
No full text The world’s fisheries face complex and high-stakes governance problems that increasingly require mobilizing diverse collectives of governance actors. How fishers and fishing organizations understand and articulate governance problems has implications for how they engage with governance institutions and the kinds of collective action they enact. In Mexico, cooperatives are a major form of organization for small-scale fishers. Fishing cooperatives form regional organizations (federations), which in turn form national organizations (confederations). These are nested or multi-scalar organizations that represent fishers’ interests and negotiate with other governance actors. Drawing on longitudinal data from assemblies of a national organization (2016–2019) – which represents more than 30,000 fishers in Mexico organized in about 300 cooperatives – as well as regional meetings involving federations and cooperatives, this study examines how cooperativist fishers in Mexico articulate problems in the governance of fisheries and to what effect. More specifically, the paper builds on scholarship about the performativity of collective action to examine the strategic discursive and affective practices through which fishers engage with major governance problems and the implications for collective action. Through the politics of multi-level cooperative institutions, specific issues are prioritized as leaders of fishers’ organizations translate diverse local-regional concerns to advance the interests of the sector at the national level. Using examples of (1) conflicts surrounding environmental conservation in the Gulf of California and (2) legacies of privatization and the decline of cooperatives in shrimp fisheries, the analysis demonstrates how discourses and affects are incorporated into specific storylines and mobilized in political spaces. Cooperativist fishers become contingently aligned along these storylines, which shapes the translation of local-regional concerns into national priorities, giving rise to a multi-scalar performative politics of collective action. </jats:p
Cell Saver for Adult Spinal Deformity Surgery Reduces Cost.
No full textStudy designRetrospective cohort.ObjectivesTo determine if the use of cell saver reduces overall blood costs in adult spinal deformity (ASD) surgery.Summary of background dataRecent studies have questioned the clinical value of cell saver during spine procedures.MethodsASD patients enrolled in a prospective, multicenter surgical database who had complete preoperative and surgical data were identified. Patients were stratified into (1) cell saver available during surgery, but no intraoperative autologous infusion (No Infusion group), or (2) cell saver available and received autologous infusion (Infusion group).ResultsThere were 427 patients in the Infusion group and 153 in the No infusion group. Patients in both groups had similar demographics. Mean autologous infusion volume was 698 mL. The Infusion group had a higher percentage of EBL relative to the estimated blood volume (42.2%) than the No Infusion group (19.6%, p ConclusionCompared to transfusing allogeneic blood, cell saver autologous infusion did not reduce the proportion or the volume of allogeneic transfusion for patients undergoing surgery for adult spinal deformity. The use of cell saver becomes cost-efficient above an EBL of 614 mL, producing a cost savings of 422.Level of evidenceLevel III
Are the Arbeitsgemeinschaft Für Osteosynthesefragen (AO) Principles for Long Bone Fractures Applicable to 3-Column Osteotomy to Reduce Rod Fracture Rates?
No full textObjectiveThe aim was to determine whether applying Arbeitsgemeinschaft für Osteosynthesefragen (AO) principles for external fixation of long bone fracture to patients with a 3-column osteotomy (3CO) would be associated with reduced rod fracture (RF) rates.Summary of background dataAO dictate principles to follow when fixating long bone fractures: (1) decrease bone-rod distance; (2) increase the number of connecting rods; (3) increase the diameter of rods; (4) increase the working length of screws; (5) use multiaxial fixation. We hypothesized that applying these principles to patients undergoing a 3CO reduces the rate of RF.MethodsPatients were categorized as having RF versus no rod fracture (non-RF). Details on location and type of instrumentation were collected. Dedicated software was used to calculate the distance between osteotomy site and adjacent pedicle screws, angle between screws and the distance between the osteotomy site and rod. Classic sagittal spinopelvic parameters were evaluated.ResultsThe study included 170 patients (34=RF, 136=non-RF). There was no difference in age (P=0.224), sagittal vertical axis correction (P=0.287), or lumbar lordosis correction (P=0.36). There was no difference in number of screws cephalad (P=0.62) or caudal (P=0.31) to 3CO site. There was a lower rate of RF for patients with >2 rods versus 2 rods (PConclusionsA portion of AO principles can be applied to 3CO to reduce RF rates. Placing more rods around a 3CO site, placing rods in multiple planes, and placing adjacent screws with a larger working length around the 3CO site is associated with lower RF rates
A New Approach to Digitizing Cultural Heritage: Constructing Immersive VR Experiences of Traditional Huizhou Architecture
No full textVernacular architectural studies are an integral part of the world’s cultural heritage research. Compared with other tangible or intangible cultural heritage, the physical properties of vernacular architecture and its site-specific nature make it difficult to be physically exhibited in museums, thus limiting the dissemination of vernacular culture and impeding the potential conservation awareness of its audiences. The development of new media technology in the 21st century, represented by virtual reality in particular, has helped to alleviate this cultural communication deadlock. This thesis focuses on the traditional architecture of Huizhou, and consists of a written paper and a digital project. The written paper explores the origins of Huizhou culture and discusses how long-term developments in ethnography, social history, and the natural environment have influenced the unique appearance and design concepts of Huizhou architecture. Moreover, based on the spatial affordances of digital media, the paper discusses how virtual reality (VR) technology can enhance the experience of, accessibility to, and interactivity with Huizhou architecture as represented through 3D reconstruction. The digital part of the thesis is a VR application called “Virtual Huizhou,” and was developed in Unreal Engine 5. This application is a 3D reconstruction of Yin Yu Tang. It will also demonstrate the role of VR in enhancing visitors’ interests and evoking cultural and emotional experiences through the following aspects: 3D models, interface design, and user experience functionalities.</p
Alterations in Magnitude and Shape of Thoracic Kyphosis Following Surgical Correction for Adult Spinal Deformity.
No full textStudy designRetrospective review of prospective multicenter data.ObjectivesThis study aimed to investigate the shape of TK before and after fusion in ASD patients treated with long fusion.MethodsASD patients undergoing posterior spinal fusions including at least T5 to L1 without prior fusion extending to the thoracic spine were included. Patients were categorized based on the preoperative T1-T12 kyphosis into: Hypo-TK (if 70°). Regional kyphosis at T10-L1 (Distal), T5-T10 (Middle), and T1-T5 (Proximal) and their relative contributions to total kyphosis were compared between groups, and the pre-to postoperative changes were investigated using paired t test.ResultsIn total, 329 patients were included in this analysis (mean age: 57 ± 16 years, 79.6% female). Preoperative T1-T12 TK for the entire cohort was 40.9 ± 2° (32% Hypo-TK, 11% Hyper-TK, 57% Normal-TK). The Hypo-TK group had the smallest distal TK (5.9 vs 17.1 & 26.0), and middle TK (8.0 vs 25.3 & 45.4), but the percentage of contribution to total kyphosis was not significantly different (Distal: 24.1% vs 34.1% vs 32.8%; Middle: 46.6% vs 53.9% vs 56.8%, all P > .1). Postoperatively, T1-12 TK increased significantly (40.9 ± 2.0° vs 57.8 ± 17.6°). Each group had a decrease in distal kyphosis (Hypo-TK 2.6 ± 10.4°; Normal-TK 8.9 ± 11.5°; Hyper-TK 14.9 ± 12°, all P P = .032).ConclusionsPosterior spinal fusion for ASD alters the magnitude and shape of thoracic kyphosis. While 60% of patients had a normal TK at baseline, 30% of those patients developed iatrogenic hyperkyphosis postoperatively. Patients with baseline hypokyphosis were more likely to be corrected to normal TK than hyperkyphotic patients. Future research should investigate TK restoration in ASD and its impact on clinical outcomes and complications
Kickstand rods and correction of coronal malalignment in patients with adult spinal deformity.
No full textPurposeCoronal malalignment (CM) is a challenging spinal deformity to treat. The kickstand rod (KR) technique is powerful for correcting truncal shift. This study tested the hypothesis that the KR technique provides superior coronal alignment correction in adult deformity compared with traditional rod techniques.MethodsA retrospective evaluation of a prospectively collected multicenter database was performed. A 2:1 matched cohort of non-KR accessory rod and KR patients was planned based on preoperative coronal balance distance (CBD) and a vector of global shift. Patients were subgrouped according to CM classification with a 30-mm CBD threshold defining CM, and comparisons of surgical and clinical outcomes among groups was performed.ResultsTwenty-one patients with preoperative CM treated with a KR were matched to 36 controls. KR-treated patients had improved CBD compared with controls (18 vs. 35 mm, P 30 mm) in the KR cohort (P = 0.70), the control cohort (P = 0.35), or the overall population (P = 0.31).ConclusionsApplication of the KR technique to coronal spinal deformity in adults allows for successful treatment of CM. Compared to traditional rod techniques, the use of KRs did not improve clinical outcome measures 1 year after spinal deformity surgery but was associated with better postoperative coronal alignment
Cancer Clonal Theory, Immune Escape, and Their Evolving Roles in Cancer Multi-Agent Therapeutics
No full textSyntactic rules predict song type matching in a songbird
No full textAbstract: Song type matching has been hypothesized to be a graded signal of aggression; however, it is often the case that variation in matching behavior is unrelated to variation in aggressiveness. An alternative view is that whether an individual matches a song is determined mainly by syntactic rules governing how songs are sequenced. In song sparrows (Melospiza melodia), two such rules are the cycling rule, which directs that a bird cycles through its song types in close to the minimum number of bouts, and the bout length rule, which directs that a long bout of a song type is followed by a long interval before that song type is sung again. The effect of these rules on matching is confirmed here for a population of eastern song sparrows. Territorial males were challenged at the end of a recording session with playback of one of their own song types. Logistic regression showed that the probability of matching the playback song type increased with the length of the interval since the subject had last sung that song type, as predicted by the cycling rule. The probability of matching decreased as prior bout length increased, as predicted by the bout length rule. In a multivariate logistic regression, interval length and prior bout length were both associated with matching and together correctly predicted matching in 81.3% of cases. The results support the syntactic constraints hypothesis, which proposes that matching is a non-signaling by-product of internal rules governing the ordering of song type sequences. Significance statement: Vocal matching has attracted widespread interest in large part because it seems an effective method of directing an aggressive message at a particular recipient. Here, we show that in an eastern population of song sparrows, decisions on whether to match another bird are largely determined by internal rules of syntax governing how a singer sequences its song types, rather than by variation in aggressiveness or other individual traits. These results support the view that vocal matching is an incidental byproduct of internal mechanisms controlling the ordering of vocalization types and so is not a signal at all. This hypothesis may be broadly applicable to vocal matching in other species