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Abstract The ocean’s major circulation system, the Atlantic Meridional Overturning Circulation (AMOC), is slowing down. Such weakening is consistent with warming associated with increasing greenhouse gases, as well as with recent decreases in industrial aerosol pollution. The impact of biomass burning aerosols on the AMOC, however, remains unexplored. Here, we use the Community Earth System Model version 1 Large Ensemble to quantify the impact of both aerosol types on the AMOC. Despite relatively small changes in North Atlantic biomass burning aerosols, significant AMOC evolution occurs, including weakening from 1920 to ~1970 followed by AMOC strengthening. These changes are largely out of phase relative to the corresponding AMOC evolution under industrial aerosols. AMOC responses are initiated by thermal changes in sea surface density flux due to altered shortwave radiation. An additional dynamical mechanism involving the North Atlantic sea-level pressure gradient is important under biomass-burning aerosols. AMOC-induced ocean salinity flux convergence acts as a positive feedback. Our results show that biomass-burning aerosols reinforce early 20th-century AMOC weakening associated with greenhouse gases and also partially mute industrial aerosol impacts on the AMOC. Recent increases in wildfires suggest biomass-burning aerosols may be an important driver of future AMOC variability.

Abstract Many regions of the planet have experienced an increase in fire activity in recent decades. Although such increases are consistent with warming and drying under continued climate change, the driving mechanisms remain uncertain. Here, we investigate the effects of increasing atmospheric carbon dioxide concentrations on future fire activity using seven Earth system models. Centered on the time of carbon dioxide doubling, the multi-model mean percent change in fire carbon emissions is 66.4 ± 38.8% (versus 1850 carbon dioxide concentrations, under fixed 1850 land-use conditions). A substantial increase is associated with enhanced vegetation growth due to carbon dioxide biogeochemical impacts at 60.1 ± 46.9%. In contrast, carbon dioxide radiative impacts, including warming and drying, yield a negligible response of fire carbon emissions at 1.7 ± 9.4%. Although model representation of fire processes remains uncertain, our results show the importance of vegetation dynamics to future increases in fire activity under increasing carbon dioxide, with potentially important policy implications.

The evolution of imaging actively shapes clinical management in the field. Ultrasonography (US), computed tomography angiography (CTA), and magnetic resonance angiography (MRA) stand out as the most extensively researched imaging modalities for ABR. Ongoing advancements include “real-time” angiography and three-dimensional (3D) surface imaging, and future prospects incorporate augmented or virtual reality (AR/VR) and artificial intelligence (AI). These technologies may further enhance perioperative efficiency, reduce donor-site morbidity, and improve surgical outcomes in ABR.

Higher concentrations of dust and secondary organic aerosol in the atmosphere, resulting from an intensified West African monsoon and enhanced emissions of biogenic volatile organic compounds, respectively, are projected to contribute to degrading air quality in a warmer world, suggest analyses of Earth system model simulations.

Summary:. Autologous reconstruction accounts for nearly one-quarter of all breast reconstruction cases in the United States, with the abdomen functioning as the most popular donor site. This case describes a 62-year-old woman who presented to our clinic with a remote history of estrogen receptor+/progesterone+ breast cancer and bilateral implant-based reconstruction. After grade IV capsular contracture of her left breast, she presented for autologous reconstruction. Due to her body habitus and prior belt lipectomy, deep inferior epigastric perforator flap reconstruction was contra-indicated. The thoracodorsal artery perforator (TDAP) flap is well described in the literature, and was chosen as an alternative salvage procedure to avoid latissimus harvest and the need for implants. The TDAP flap is often limited in volume and prone to distal tip necrosis, limiting its use in breast reconstruction. We have previously demonstrated the utility of the surgical delay phenomenon in improving the reliability of superficial inferior epigastric artery free flap breast reconstruction. In this case, we demonstrate the surgically delayed TDAP flap as a viable alternative to the latissimus flap with implants for bilateral total autologous breast reconstruction.

Background:. Since its introduction for autologous breast reconstruction in 2010, the profunda artery perforator (PAP) flap has emerged as a preferred choice when an abdominal flap is suboptimal. The traditional transverse design (tPAP) was popularized, given the inconspicuous donor scar. A diagonal design (dPAP) has since evolved to address some of the shortcomings of the tPAP. The authors aimed to compare outcomes of tPAP/dPAP flaps harvested for breast reconstruction by a single surgeon. Methods:. A retrospective review was conducted from 2017 to 2022 of patients undergoing tPAP versus dPAP-based breast reconstruction by a single surgeon at a tertiary cancer center. Patient variables and operative variables were assessed. Need for additional symmetrizing breast procedures were compared. Complications and BREAST-Q patient-reported outcome measures were analyzed. Results:. Thirty-nine flaps were used to reconstruct 35 breasts in 24 patients. Average follow-up for the group was 1.8 years. The groups were similar with respect to demographics. The majority of dPAP flaps had two perforators, whereas most tPAP flaps had one perforator. The dPAP flaps had greater average weights, width, and overall surface area. There were no cases of partial/total flap loss. Complications and PROM results were similar between the two groups. Conclusions:. The dPAP design allows for a larger skin paddle and greater tissue harvest and capture of cutaneous perforators, without increasing the risk of complications or compromising satisfaction. It should be considered as a viable option in patients unable to undergo abdominal-based reconstruction. Additional patients and multi-institutional efforts are necessary to better compare advantages of either design.

Improved air quality is projected to weaken Atlantic Meridional Overturning Circulation but the effects can be offset by methane reductions, according to air quality control simulations based on the Shared Socio-economic Pathways.

Summary:. The thoracodorsal artery perforator (TDAP) flap has a long vascular pedicle that is ideal for lower extremity reconstruction, but it generally relies on the presence of a dominant septocutaneous perforator vessel. Surgical delay optimizes flap survival by creating relative ischemia to augment perforator vessels. In this report, we describe the use of a delayed free TDAP flap in the setting of an absent dominant perforator vessel for the reconstruction of a calcaneal degloving injury. A 22-year-old actively smoking patient with a body mass index of 33.5 presented with a nonhealing left heel wound with overlying necrotic changes after traumatic degloving injury. The entire weight-bearing portion of the calcaneal fat pad and the flanking regions were debrided. The TDAP flap was elevated, revealing three small thoracodorsal artery perforators. Given that a dominant perforator was absent, the flap was surgically delayed. Free-tissue transfer occurred 8 days later. This operation was conducted entirely in left lateral decubitus with simultaneous wound preparation and flap harvest. The flap was elevated on two perforators to elongate the pedicle’s length and inset to cover exposed calcaneus and pad the heel. Six months postoperatively, the patient is doing well without flap compromise or ulceration. The TDAP flap is a versatile microsurgical tool, and surgical delay extends the utility of this flap when a dominant septocutaneous perforator is unavailable. Recipient site debridement may occur simultaneously with the TDAP delay procedure. Importantly, only one position is required for flap elevation, microsurgical anastomosis, and insetting, thus obviating intraoperative repositioning.

We investigate the effective radiative forcing (ERF) of anthropogenic aerosols using simulations from seven Earth System Models participating in the Coupled Model Intercomparison Project Phase 6 (CMIP6). The ERF of individual aerosol species (black carbon, organic carbon, sulphates) is quantified along with the all-aerosol ERF and decomposed into its aerosol–radiation interactions (ARI), aerosol–cloud interactions (ACI) and surface albedo (ALB) components, using the method proposed by Ghan in 2013. We find that the total anthropogenic aerosol ERF at the top of the atmosphere (TOA) is negative, mainly due to aerosol–cloud interactions. Sulphates exhibit a strongly negative ERF especially over industrialized regions of the Northern Hemisphere, such as Europe, North America, East and South Asia, while black carbon exerts a positive ERF predominantly over East and South Asia.

Abstract Air pollution is largely attributed to anthropogenic aerosols, with the role of natural aerosols, including sea salt, dust, and other terrestrial emissions considered to be less important. However, natural aerosols have strong geographic gradients and this suggests that spatially invariant air quality guidelines may handicap regions close to natural sources. We use climate models to construct a view of pre‐industrial “pristine” air quality, including fine particulate matter with diameters less than 2.5 µm (PM2.5). Under pristine conditions, PM2.5 levels over regions in geographic proximity to dust sources, including parts of Africa and Asia, exceed World Health Organization air quality guidelines. We estimate that this pristine air pollution, which is unassociated with human activities, impacts up to about one billion people globally. The results show that natural aerosols, with strong geographic gradients, can lead to poor air quality over regions close to sources, and that in many areas no amount of anthropogenic emission reductions will result in clean air.

Summary:. Historically, immediate dental implants have been reserved for patients with benign disease, with full dental rehabilitation rarely being accomplished in the oncologic setting due to concerns related to implant survival, flap compromise, and delay in initiation of adjuvant therapy. Recent developments in technology have made immediate dental implants using virtual surgical planning safe and reliable. At Memorial Sloan Kettering Cancer Center, we have implemented a workflow for immediate dental implant placement in the oncologic patient population that has become a routine part of maxillary and mandibular reconstruction. This approach begins with a multidisciplinary virtual surgical planning session and custom dental splints to be used for cutting and inset guides. Dental implants are placed intraoperatively at the time of tumor resection and reconstruction with the fibula flap. A temporary prosthesis, which can be worn during radiation therapy, is placed following a vestibuloplasty, approximately 4–6 weeks after the initial reconstruction. After the completion of radiation therapy and the resolution of edema, a permanent prosthesis is placed. When critically evaluating our experience, we have found that patients undergoing immediate dental implant placement have higher rates of implant survival and no delay in adjuvant therapy. The protocol described here in detail has successfully expanded the indications for immediate dental rehabilitation in the oncologic patient population.

Summary:. Virtual surgical planning (VSP) with computer-aided design and computer-aided modeling (CAD/CAM) enables the opportunity to provide personalized medicine in complex head and neck reconstruction. This innovative technology allows ablative and reconstructive surgeons to virtually create and manipulate three-dimensional anatomic models to plan both the resection and reconstruction of complicated maxillofacial defects. Studies demonstrate improvements in preoperative planning, operative efficiency and accuracy, and postoperative outcomes. VSP facilitates immediate dental implantation in selected patients, which can improve the likelihood of achieving dental restoration. This article outlines strategies for technique optimization as well as the applications, advantages and disadvantages of VSP in complex oncologic head and neck reconstruction.

Summary:. Reconstruction of segmental maxillary or mandibular defects with osteocutaneous free flaps can be reliably accomplished; however, buccal or lingual rotation of the fibula during rigid fixation can render immediate endosseous implant position unusable for functional dental rehabilitation. To address this issue, a custom inset guide is introduced which utilizes surface topography of the immediately placed dental implant abutments and the patient’s dentition to orient the fibula segments during inset. Use of this technique facilitates successful endosseous implant position to optimize postoperative functional rehabilitation.

Summary:. Although the deep inferior epigastric artery perforator flap remains the gold standard for autologous breast reconstruction, many patients are not candidates for this surgery. A variety of thigh-based flaps have been used including the diagonal upper gracilis (DUG) flap, vertical upper gracilis flap, profunda artery perforator (PAP) flap, and lateral thigh perforator flap. However, each of these techniques has a unique set of benefits and drawbacks in terms of wound healing, donor site morbidity, and potential for lymphedema. We describe the first report of a sensate diagonal PAP flap for breast reconstruction: combining the benefits of the DUG (wider skin paddle and reliable wound healing) with the benefits of the PAP (muscle-sparing technique and greater distance from the lymphatic collectors). This was the authors' sentinel case in a woman with paraplegia and chronic leg swelling. Preoperative imaging, markings, and technical details are presented along with postoperative results. In the appropriately selected patient, this flap offers several advantages: a 2-team approach to reconstruction, ample tissue for breast reconstruction, potential neurotization for breast sensibility, wound closure in resting skin tension lines, and avoidance of the lymphatic drainage to the lower extremity. The diagonal PAP flap provides a muscle-sparing alternative to the DUG flap while minimizing the risk of lymphedema. Future studies are needed to assess the donor site morbidity of this flap; however, this case proves the safety and reliability of the diagonal PAP flap in our breast reconstruction population.

The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb) is the smallest chromosome in Drosophila melanogaster, but it is substantially larger (>18.7 Mb) in D. ananassae. To identify the major contributors to the expansion of the F element and to assess their impact, we improved the genome sequence and annotated the genes in a 1.4-Mb region of the D. ananassae F element, and a 1.7-Mb region from the D element for comparison. We find that transposons (particularly LTR and LINE retrotransposons) are major contributors to this expansion (78.6%), while Wolbachia sequences integrated into the D. ananassae genome are minor contributors (0.02%). Both D. melanogaster and D. ananassae F-element genes exhibit distinct characteristics compared to D-element genes (e.g., larger coding spans, larger introns, more coding exons, and lower codon bias), but these differences are exaggerated in D. ananassae. Compared to D. melanogaster, the codon bias observed in D. ananassae F-element genes can primarily be attributed to mutational biases instead of selection. The 5′ ends of F-element genes in both species are enriched in dimethylation of lysine 4 on histone 3 (H3K4me2), while the coding spans are enriched in H3K9me2. Despite differences in repeat density and gene characteristics, D. ananassae F-element genes show a similar range of expression levels compared to genes in euchromatic domains. This study improves our understanding of how transposons can affect genome size and how genes can function within highly repetitive domains.

California lies in the transition zone where mid-latitude regions are expected to become wetter and subtropical regions drier, and precipitation projections for the region remain uncertain. Here the authors use a multitude of models to show consistent increases in California precipitation under a business-as-usual scenario.

Objectives:. The authors seek to highlight some of the ongoing challenges related to complex oncologic reconstruction and the current solutions to these problems. Summary:. The standard of care in reconstruction following oncologic resection is continually evolving. Current frontiers in breast reconstruction include addressing animation deformity through prepectoral reconstruction, offering autologous reconstruction to patients with limited donor sites, and improving postoperative sensation with innervation of free tissue transfer. Facial nerve reconstruction and contour defects pose an ongoing challenge in patients undergoing parotidectomy requiring complex nerve transfers and autologous reconstruction. Lymphedema is not a monolithic disease, and as our understanding of the pathophysiology improves, our surgical algorithms continue to evolve.

Summary:. Perforator-free flaps, in autologous breast reconstruction, have expanded to exploit tissue available at smaller donor sites while retaining high success and low risk rates. Abdominal based flaps, such as the deep inferior epigastric perforator, remain the most common; however, when the abdomen is not an appropriate donor site, lower extremity flaps are options. The profunda artery perforator has the benefit of hiding unsightly scar in the gluteal crease but has the drawback of poor donor site volume. Our mosaic fleur-de-profunda artery perforator flap technique for breast reconstruction has shown to increase volume with the addition of a vertical limb, include full angiosome of perforators, and exhibit donor site morbidity equivalent to a medial thigh lift.

Summary:. Full dental rehabilitation following segmental mandibulectomy or maxillectomy for oncologic tumor ablation should be the goal for every patient. But despite advances in technology and reconstructive techniques, many patients do not achieve timely or complete oral rehabilitation. Recognizing this fault, we recently adopted an innovative workflow to increase the number of patients undergoing dental restoration, irrespective of tumor pathology or need for adjuvant radiotherapy. Preoperatively, every osseous jaw reconstruction undergoes virtual surgical planning to incorporate the placement of endosseous implants into the fibula osteocutaneous free flap. The dental implants are then placed intraoperatively at the time of tumor ablation and reconstruction. Four-to-six weeks following the initial surgery, the patient returns to the operating room for vestibuloplasty and exposure of the dental implants. Within 3 days of the vestibuloplasty, a temporary dental prosthesis is placed in the dental clinic, and the patient can then begin radiation therapy if needed. Following adjuvant radiation therapy, the temporary prosthesis can be replaced with a permanent one. At our institution, this innovative workflow has allowed for earlier aesthetic restoration of the jaw and greatly expanded the number of patients able to achieve oral rehabilitation. Herein, we describe this innovative workflow and provide technical pearls for successful execution.

Abstract Background Nipple-sparing mastectomy (NSM) allows for complete preservation of the nipple-areola complex and is increasing in popularity. Autologous options in NSM provide an aesthetic reconstruction in a single stage; however, donor tissue may be scarce in these patients. Stacked microsurgical breast reconstruction, especially in unilateral cases, is an attractive alternative in NSM that is yet to be described. Methods Patients undergoing NSM with stacked autologous flap reconstruction were identified with demographics, intraoperative variables, and outcomes analyzed. Results Six patients who underwent unilateral NSM with stacked autologous free flaps were identified. The average patient age was 50.17 years and body mass index was 21.67. Average follow-up was 28.62 months. Five (83.3%) patients underwent unilateral NSM and reconstruction for a therapeutic indication. The average mastectomy weight was 235.67 grams. All patients were reconstructed with stacked deep inferior epigastric perforator flaps. The average total flap weight was 397.33 grams. Anastomoses in five stacked flaps (83.3%) were performed in an anterograde/retrograde fashion to the internal mammary (IMA) vessels. In one (16.7%) stacked flap, the two flaps were anastomosed in series to the IMA. There were no major complications and three incidences of minor complications. There were no incidences of partial or complete flap loss. The average number of secondary procedures was 0.83 per patient. Conclusion Stacked microsurgical autologous breast flaps provide an optimal reconstruction after NSM and may be considered the reconstruction of choice in patients undergoing unilateral NSM with inadequate donor site tissue for single-flap reconstruction.

The authors present the case of a 42-year-old female patient who underwent autologous breast reconstruction using a new perforator flap designed from the medial and posterior thigh. Due to a prior abdominoplasty, the patient's abdominal donor site was unavailable to reconstruct her large, ptotic breasts, so an alternate approach was undertaken. The fleur-de-PAP flap is based on the same perforators employed by the standard profunda artery perforator (PAP) flap, but simultaneously incorporates tissue from both the transverse and vertical PAP flap skin paddles. This design maximizes flap volume at a single donor site and provides a reasonable secondary option for autologous reconstruction in large-breasted patients in whom the abdomen is not available.