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The article focuses on comparing the accuracy of Invisalign in achieving predicted tooth movement of the maxillary central incisors and locating the center of rotation in labio-palatal direction, analyzing the impact of different wear protocols. Topics include assessing the discrepancy between predicted and achieved angular movements, exploring root movement control, and comparing wear protocols' efficacy in achieving predicted tooth movements and center of rotation.

Hydrofluorocarbons (HFCs) are widely used as cooling agents in refrigeration and air conditioning, as solvents in industrial processes, as fire-extinguishing agents, for foam blowing, and as aerosol propellants. They have been used in large quantities as the primary substitutes for ozone-depleting substances regulated under the Montreal Protocol. However, many HFCs are potent greenhouse gases (GHGs) and as such subject to global phase-down under the Kigali Amendment (KA) to the Montreal Protocol. In this study, we develop a range of long-term scenarios for HFC emissions under varying degrees of stringency in climate policy and assess co-benefits in the form of electricity savings and associated reductions in GHG and air pollutant emissions. Due to technical opportunities to improve energy efficiency in cooling technologies, there exist potentials for significant electricity savings under a well-managed phase-down of HFCs. Our results reveal that the opportunity to simultaneously improve energy efficiency in stationary cooling technologies could bring additional climate benefits of about the same magnitude as that attributed to the HFCs phase-down. If technical energy efficiency improvements are fully implemented, the resulting electricity savings could exceed 20 % of future global electricity consumption, while the corresponding figure for economic energy efficiency improvements would be about 15 %. The combined effect of HFC phase-down, energy efficiency improvement of the stationary cooling technologies, and future changes in the electricity generation fuel mix would prevent between 411 and 631 PgCO2 equivalent of GHG emissions between 2018 and 2100, thereby making a significant contribution towards keeping the global temperature rise below 2 ∘C. Reduced electricity consumption also means lower air pollution emissions in the power sector, estimated at about 5 %–10 % for sulfur dioxide (SO2), 8 %–16 % for nitrogen oxides (NOx), and 4 %–9 % for fine particulate matter (PM2.5) emissions compared with a pre-Kigali baseline. [ABSTRACT FROM AUTHOR]

Myelofibrosis is an indicator of poor prognosis in myeloproliferative neoplasms (MPNs), but the precise mechanism(s) contributing to extracellular matrix remodeling and collagen deposition in the bone marrow (BM) niche remains unanswered. In this study, we isolated mesenchymal stromal cells (MSCs) from mice transplanted with wild-type thrombopoietin receptor (MPLWT) and MPLW515L retroviral-transduced bone marrow. Using MSCs derived from MPLW515-transplant recipients, excessive collagen deposition was maintained in the absence of the virus and neoplastic hematopoietic cells suggested that the MSCs were reprogrammed in vivo. TGFβ production by malignant megakaryocytes plays a definitive role promoting myelofibrosis in MPNs. However, TGFβ was equally expressed by MSCs derived from MPLWT and MPLW515L expressing mice and the addition of neutralizing anti-TGFβ antibody only partially reduced collagen secretion in vitro. Interestingly, profibrotic MSCs displayed increased levels of pSmad3 and pSTAT3 suggesting that inflammatory mediators cooperating with the TGFβ-receptor signaling may maintain the aberrant phenotype ex vivo. FGFb is a known suppressor of TGFβ signaling. Reduced collagen deposition by FGFb-treated MSCs derived from MPLW515L mice suggests that the activating pathway is vulnerable to this suppressive mediator. Therefore, our findings have implications for the future investigation of therapies to reverse fibrosis in MPNs. [ABSTRACT FROM AUTHOR]

Long-distance road-freight transport emits a large share of Germany's greenhouse gas (GHG) emissions. A potential solution for reducing GHG emissions in this sector is to use green hydrogen in fuel cell electric vehicles (FC-HDV) and establish an accompanying hydrogen refueling station (HRS) network. In this paper, we apply an existing refueling network design model to a HDV-HRS network for Germany until 2050 based on German traffic data for heavy-duty trucks and estimate its costs. Comparing different fuel supply scenarios (pipeline vs. on-site), The on-site scenario results show a network consisting of 137 stations at a cost of 8.38 billion € per year in 2050 (0.40 € per vehicle km), while the centralized scenario with the same amount of stations shows a cheaper cost with 7.25 billion euros per year (0.35 € per vehicle km). The hydrogen cost (LCOH) varies from 5.59 €/kg (pipeline) to 6.47 €/kg (on-site) in 2050. • Assessment of new refueling network design model and its cost for Germany in 2050. • Results show a network consisting of 137 stations. • Cost of an HDV-HRS network for on-site production is 8.38 bn€/a (6.47 €/kgH 2). • Cost of an HDV-HRS network for centralized production is 7.25 bn€/a (5.59 €/kg H 2). • Centralized production needs H 2 pipeline of 5381 km with 0.23 m average diameter. [ABSTRACT FROM AUTHOR]

• Simulated hydrogen (H 2) demand from 2030 California fuel cell vehicle deployment. • Simulated electrolysis H 2 production using PLEXOS power system model of Western US. • Flexible electrolysis operation can reduce system costs, carbon dioxide emissions. Hydrogen fuel cell electric vehicles (FCEVs) have been proposed as an option for lowering carbon dioxide (CO 2) and pollutants emissions from the transportation sector, when implemented in combination with green hydrogen production methods such as water electrolysis powered by renewable electricity. FCEVs also have the added advantages of high specific energy density and rapid refueling, two important challenges that battery electric vehicles have not yet fully overcome. Moreover, flexible operation of electrolysis could support the grid and lower electricity costs. In this paper, we simulate time-varying FCEV hydrogen refueling demand for light, medium- and heavy-duty vehicles met using electrolysis systems distributed throughout the Western U.S. power system. We find that by oversizing electrolyzers the resulting load flexibility results in different hydrogen generation temporal profiles, average electricity costs, renewable curtailment levels, and CO 2 emissions. Our results indicate that increasing hydrogen production flexibility lowers hydrogen and electricity generation cost and CO 2 emissions, but there is a tradeoff between lowering operational cost and increasing electrolyzer capital cost, yielding a minimum total system cost at a size corresponding to between 80% and 90% annual capacity factor assuming a future electrolyzer cost of $300/kW. [ABSTRACT FROM AUTHOR]