We present new JVLA observations of the high-mass cluster-forming region W51A from 2 to 16 GHz with resolution θfwhm ≈ 0.3−0.5″. The data reveal a wealth of observational results: (1) Currently ...forming, very massive (proto-O) stars are traced by o - H2CO21,1−21,2 emission, suggesting that this line can be used efficiently as a massive protostar tracer; (2) there is a spatially distributed population of ≲mJy continuum sources, including hypercompact H ii regions and candidate colliding wind binaries, in and around the W51 proto-clusters; and (3) there are two clearly detected protoclusters, W51e and W51 IRS2, that are gas-rich but may have most of their mass in stars within their inner ≲0.05 pc. The majority of the bolometric luminosity in W51 most likely comes from a third population of OB stars between these clusters. The presence of a substantial population of exposed O-stars coincident with a population of still-forming massive stars, together with a direct measurement of the low mass loss rate via ionized gas outflow from W51 IRS2, implies that feedback is ineffective at halting star formation in massive protoclusters. Instead, feedback may shut off the large-scale accretion of diffuse gas onto the W51 protoclusters, implying that they are evolving toward a state of gas exhaustion rather than gas expulsion. Recent theoretical models predict gas exhaustion to be a necessary step in the formation of gravitationally bound stellar clusters, and our results provide an observational validation of this process.
We report the first experimental observation of a doubly-charged defect in diamond, SiV2-, in silicon and nitrogen co-doped samples. We measure spectroscopic signatures we attribute to substitutional ...silicon in diamond, and identify a silicon-vacancy complex decorated with a nearest-neighbor nitrogen, SiVN, supported by theoretical calculations. Samples containing silicon and nitrogen are shown to be heavily photochromic, with the dominant visible changes due to the loss of SiV0/- and gain in the optically-inactive SiV2-.
The ongoing debate about costs and benefits of wood‐pellet based bioenergy production in the southeastern United States (SE USA) requires an understanding of the science and context influencing ...market decisions associated with its sustainability. Production of pellets has garnered much attention as US exports have grown from negligible amounts in the early 2000s to 4.6 million metric tonnes in 2015. Currently, 98% of these pellet exports are shipped to Europe to displace coal in power plants. We ask, ‘How is the production of wood pellets in the SE USA affecting forest systems and the ecosystem services they provide?’ To address this question, we review current forest conditions and the status of the wood products industry, how pellet production affects ecosystem services and biodiversity, and what methods are in place to monitor changes and protect vulnerable systems. Scientific studies provide evidence that wood pellets in the SE USA are a fraction of total forestry operations and can be produced while maintaining or improving forest ecosystem services. Ecosystem services are protected by the requirement to utilize loggers trained to apply scientifically based best management practices in planning and implementing harvest for the export market. Bioenergy markets supplement incomes to private rural landholders and provide an incentive for forest management practices that simultaneously benefit water quality and wildlife and reduce risk of fire and insect outbreaks. Bioenergy also increases the value of forest land to landowners, thereby decreasing likelihood of conversion to nonforest uses. Monitoring and evaluation are essential to verify that regulations and good practices are achieving goals and to enable timely responses if problems arise. Conducting rigorous research to understand how conditions change in response to management choices requires baseline data, monitoring, and appropriate reference scenarios. Long‐term monitoring data on forest conditions should be publicly accessible and utilized to inform adaptive management.
Category:
Lesser Toes
Introduction/Purpose:
Lesser toe metatarsophalangeal joint instability, secondary to plantar plate tear, has been the focus of numerous recent publications, majority reporting ...on repair through a dorsal approach. A plantar approach has been described with the advantage of direct ligamentous repair or repair to bone, which follows conventional techniques employed throughout the body. Previous clinical studies have shown success in deformity correction and longevity of both approaches. The proponents of the dorsal approach advocate that indirect repair of the plantar plate avoids perceived risks of complications with a plantar incision, without evidence of superior outcomes. The purpose of this study was to investigate the safety and efficacy of direct plantar approach to plantar plate repairs by reporting the rate of specific complications in a large clinical series.
Methods:
This was an IRB approved retrospective study of 204 plantar plate repairs, in 185 patients, (194 lesser MTP, 10 hallux MTP) with average age of 56 and mean BMI of 28. Surgical technique involved repair with absorbable braided suture (88%) versus suture anchor (12%) with or without MTPJ pinning (80%). Mean follow up was 53 weeks (range 5-170). Patients were screened for associated risk factors including diabetes mellitus (8%), tobacco use (5%), neuropathy (1%) and additional concurrent procedures (96%). Complications were defined as superficial or deep infection, painful scar, and reoperation. Analysis was conducted by using Wilcoxon-Mann-Whitney test or Fisher’s exact tests for continuous and categorical variables, respectively. Risk factors were analyzed using univariate logistic analysis to produce odds ratios (OR) with 95% confidence interval (CI) and an inclusion criterion of a p-value > 0.2 for multivariate analysis as determined by Wald tests (significance at p<0.05 for final modeling).
Results:
Overall, there were 31 total complications (15%) demonstrated by 14 superficial infections (6.8%) and 17 painful scars (8.3%) along with three reoperations (1.4%). All reoperations were performed for deformity or instability, not scar revision. There were no deep infections. No increased odds of complications were found with suture anchor repair, MTPJ pinning, neuropathy, or diabetes. Patients that used tobacco had 7.5 (CI 1.66- 34.06) the odds of developing any wound complication compared with nonsmokers. Tobacco use was also found to significantly increase the odds for superficial infection by 9.8 (CI 2.08 - 46.15). There was no increase in painful scar or reoperation in tobacco users. This study did not find an increased complication rate with additional ipsilateral procedures performed at the time of surgery.
Conclusion:
To our knowledge, this is the largest study evaluating the direct plantar approach to plantar plate repair, as well as the evaluation of associated complications with the plantar incision. With low complication and minimal reoperation rates, the results of this study have demonstrated the clinical viability of plantar based incisions. Previous studies have demonstrated the success of plantar plate repair and correction of deformity with a direct approach. This case series further demonstrates the safety and efficacy of plantar based incisions, particularly for direct plantar plate repairs.
Background:
Lesser toe metatarsophalangeal joint (MTPJ) instability, secondary to plantar plate tear, has been the focus of numerous recent publications, the majority reporting on repair through a ...dorsal approach. A plantar approach has been described with the advantage of direct ligamentous repair or repair to bone, which follows conventional techniques employed throughout the body. Previous clinical studies have shown success in deformity correction and the longevity of both approaches. The proponents of the dorsal approach advocate that indirect repair of the plantar plate avoids perceived risks of complications with a plantar incision without evidence of superior outcomes. The purpose of this study was to investigate the safety and efficacy of the direct plantar approach to plantar plate repairs (PPRs) by reporting the rate of specific complications in a large clinical series.
Methods:
This was the institutional review board (IRB) approved retrospective study of 204 PPRs in 185 patients (194 lesser MTP, 10 hallux MTP) with an average age of 56 and a mean body mass index (BMI) of 28. Surgical technique involved repair with absorbable braided suture (88%) versus suture anchor (12%) with or without MTPJ pinning (80%). Mean follow up was 53 weeks (range 5–170). Patients were screened for associated risk factors, including diabetes mellitus (8%), tobacco use (5%), neuropathy (1%), and additional concurrent procedures (96%). Complications were defined as superficial or deep infection, painful scars, and reoperation. Analysis was conducted using the Wilcoxon-Mann-Whitney test or Fisher’s exact tests for continuous and categorical variables, respectively. Risk factors were analyzed using univariate logistic analysis to produce odds ratios (OR) with a 95% confidence interval (CI) and an inclusion criterion of a P-value, P > .2 for multivariate analysis as determined by Wald tests (significance at P < .05 for final modeling).
Results:
Overall, there were 31 total complications (15%) demonstrated by 14 superficial infections (6.8%) and 17 painful scars (8.3%) along with three reoperations (1.4%). All reoperations were performed for deformity or instability, not scar revision. There were no deep infections. No increased odds of complications were found with suture anchor repair, MTPJ pinning, neuropathy, or diabetes. Patients that used tobacco had 7.5 (CI 1.66, 34.06) the odds of developing any wound complication compared with nonsmokers. Tobacco use was also found to significantly increase the odds of superficial infection by 9.8 (CI 2.08, 46.15). There was no increase in painful scars or reoperation in tobacco users. This study did not find an increased complication rate with additional ipsilateral procedures performed at the time of surgery.
Conclusion:
To our knowledge, this is the largest study evaluating the direct plantar approach to PPR as well as the evaluation of associated complications with the plantar incision. With low complication and minimal reoperation rates, the results of this study have demonstrated the clinical viability of plantar-based incisions. Previous studies have demonstrated the success of PPR and correction of deformity with a direct approach. This case series further demonstrates the safety and efficacy of plantar-based incisions, particularly for direct PPRs.
Level of Evidence:
IV Retrospective Case Series
Category:
Lesser Toes
As the global population increases and becomes more affluent, biomass demands for food and biomaterials will increase. Demand growth is further accelerated by the implementation of climate policies ...and strategies to replace fossil resources with biomass. There are, however, concerns about the size of the prospective biomass demand and the environmental and social consequences of the corresponding resource mobilization, especially concerning impacts from the associated land‐use change. Strategically integrating perennials into landscapes dominated by intensive agriculture can, for example, improve biodiversity, reduce soil erosion and nutrient emissions to water, increase soil carbon, enhance pollination, and avoid or mitigate flooding events. Such “multifunctional perennial production systems” can thus contribute to improving overall land‐use sustainability, while maintaining or increasing overall biomass productivity in the landscape. Seven different cases in different world regions are here reviewed to exemplify and evaluate (a) multifunctional production systems that have been established to meet emerging bioenergy demands, and (b) efforts to identify locations where the establishment of perennial crops will be particularly beneficial. An important barrier towards wider implementation of multifunctional systems is the lack of markets, or policies, compensating producers for enhanced ecosystem services and other environmental benefits. This deficiency is particularly important since prices for fossil‐based fuels are low relative to bioenergy production costs. Without such compensation, multifunctional perennial production systems will be unlikely to contribute to the development of a sustainable bioeconomy.
This article is categorized under:
Bioenergy > Systems and Infrastructure
Bioenergy > Climate and Environment
Energy Policy and Planning > Climate and Environment
Seven different cases in different world regions are here reviewed to exemplify and evaluate (a) establishment of multifunctional production systems to meet emerging bioenergy demands, and (b) efforts to identify specific locations where the establishment of perennial crops will be particularly beneficial
With the development of the Edmonton Protocol, pancreatic islet transplantation (PIT) now offers insulin-dependent diabetic patients metabolic stability. The PIT Food and Drug Administration (FDA) ...regulations, pancreatic islet isolation (PII) techniques, and clinical PIT protocols are challenging and make PIT program development daunting.
Review of the establishment of a PIT program through a collaborative relationship with a remote PIT/PII center.
Four key elements are required: (1) development of a collaborative relationship with an established PIT/PII center, (2) achievement of institutional review board and FDA approval at both centers, (3) generation of standard operating procedures, and (4) development of a multidisciplinary PIT team.
Securing a collaborative relationship with an experienced PIT/PII center permitted our program to develop in less than 18 months. Twenty-two PITs were completed in the first clinical year.
Collaboration with an experienced PIT/PII center allows developing programs to focus on patient safety and care, prudent use of pancreata, and consolidates PII expertise and experience.
Cotinine, the principal metabolite of nicotine found in smokers' seminal plasma, has been shown to adversely affect sperm functionality while quercetin, a flavonoid with diverse properties is ...associated with several in vivo and in vitro health benefits. The aim of this study was to investigate the potential benefits of quercetin supplementation against damage caused by the by-products of tobacco smoke in human sperm cells.
Washed human spermatozoa from 10 normozoospermic donors were treated with nutrient medium (control), quercetin (30 μmol/L) and cotinine (190 μg/mL, 300 ng/mL) with or without quercetin for 60 and 180 min incubation periods. Computer-aided sperm analysis was used to assess sperm motility while acrosome-reacted cells were identified under a fluorescent microscope using fluorescein isothiocyanate-labelled Pisum Sativum Agglutinin as a probe, viability was assessed by means of a dye exclusion staining technique (eosin/nigrosin) and oxidative stress by flow cytometry using dihydroethidium as a probe. Values were expressed as mean ± S.E.M. as compared by ANOVA.
Higher cotinine concentrations reduced the number of viable cells after 60 and 180 min of exposure while viability of cells was increased in the cotinine aliquots supplemented with quercetin after 180 min of exposure when compared with cotinine only treated group.
This study indicates that the ameliorating ability of quercetin on cotinine-induced decline in sperm function is associated with increased number of viable cells.
We present new JVLA observations of the high-mass cluster-forming region W51A from 2 to 16 GHz with resolution \({\theta}_{fwhm} \approx\) 0.3 - 0.5". The data reveal a wealth of observational ...results: (1) Currently-forming, very massive (proto-O) stars are traced by o-H2CO \(2_{1,1}-2_{1,2}\) emission, suggesting that this line can be used efficiently as a massive protostar tracer. (2) There is a spatially distributed population of \(\sim\)mJy continuum sources, including hypercompact H ii regions and candidate colliding wind binaries, in and around the W51 proto-clusters. (3) There are two clearly detected protoclusters, W51e and W51 IRS2, that are gas-rich but may have most of their mass in stars within their inner \(\sim\) 0.05 pc. The majority of the bolometric luminosity in W51 most likely comes from a third population of OB stars between these clusters. The presence of a substantial population of exposed O-stars coincident with a population of still-forming massive stars, along with a direct measurement of the low mass loss rate via ionized gas outflow from W51 IRS2, together imply that feedback is ineffective at halting star formation in massive protoclusters. Instead, feedback may shut off the large-scale accretion of diffuse gas onto the W51 protoclusters, implying that they are evolving towards a state of gas exhaustion rather than gas expulsion. Recent theoretical models predict gas exhaustion to be a necessary step in the formation of gravitationally bound stellar clusters, and our results provide an observational validation of this process.
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