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Climate change is a global issue affecting our lives, surrounding environments, and socioeconomic sectors. Accordingly, the recently published IPCC sixth assessment report emphasizes the role of forests as a source of greenhouse gas sink and shows the importance of climate resilient development pathways (CRDPs). South Korea is also putting forth policies such as the ‘2030 NDC’ and ‘2050 LED’ and is trying to find sustainable forest management measures to respond to the new climate change regime. Therefore, this study sought strategic measures to solve problems such as age class imbalance and mortality increase due to climate change in forests using the Korean dynamic stand growth model. Furthermore, CRDP was selected through recently announced SSP climate data and policy-based forest management scenarios to respond to the new climate change regime. As a result, the climate scenario is SSP1, the forest management scenario is when clear-cut harvest according to the legal final cutting age and thinning is implemented about 200,000 ha, reforestation of appropriate species to respond to climate change, and access to the forest road is within 1km, it was found that the overall growth of the forest increased. Although the current growth of 4.3m3 ha-1 decreases to 2.39m3 ha-1 in 2050, it is predicted to increase to 3.16m3 ha-1 in 2100 through the growth of species suitable for the climate and balance of age classes. In addition, it was analyzed to contribute to the increase in sequestration and carbon storage in logs due to harvest. In conclusion, this study is meaningful in that it presents a future strategy for responding to the new climate regime by reflecting the environmental and ecological characteristics of South Korea.

Recently, the action on climate crisis response was emphasized with spread of carbon neutrality from the international community, and the role of forests which is carbon sink was further accentuated. Forest is an important role to respond climate change. Therefore, it could be utilized for the strategy for achieving carbon neutrality. Forest in South Korea account for approximately 63 percent (6,286,438 ha) of land area. In this study, KO–G–Dynamics (Korean dynamic stand growh) model was used for estimating carbon sink with forest management considering watershed, which could help decision making through not fragmented but consistent forest management. Korean reach file (KRF) and forest functions (production forest, disaster prevention for forest etc.) classification map were used for considering watershed and each function. Especially, forest having different functions is applied to different methods of forest management. In addition, in the study, the data including species and age etc., which are representing the forest characteristics, based on 1 ha (100 m x 100m) resolution were used. Compared with a proceeding studies and national statistics, more accurate stem volumes (1,058 million m3 in 2020) and biomass (1,245 million ton in 2020) were estimated. In addition, the study is significant in the sense that diverse management methods in accordance with forest functions and watershed are considered. Furthermore, accurate modeling is possible through understanding of inhomogeneity on forest stands and forest in island area. It could help decision making of forest policy

Due to the land degradation, the land use conflicts have intensified, and there is an increasing necessity to adapt sustainable land management. Sustainable land management deals with the demands for land in terms of not only human society but also the nature conservation and biodiversity. To persue and realize sustainable land management, the indicators and evaluation system are necessary, and ecosystem services has emerged as the proper indicator for sustainable land management. This study focused on the balance between the demand and supply of ecosystem services. If the balance between them was maintained or supply exceeded demand, the land can be assessed to be managed sustainably. In this study, CO2 sequestration, Heat mitigation, and water provision were assessed as ecosystem service in South Korea. The supply of each ecosystem service was evaluated by using related models which had been developed and used widely in previous studies. The demand of each ecosystem service was defined based on specific figures which had already suggested as policy goals in South Kroea in purpose of drawing social consensus. Afterwards, the ecosystem services supply and demand ratio (ESDR) were calculated to show the balance between supply and demand quantified by region. As a result, the exessive demand for CO2 sequestration service was found compared to supply. The supply of heat mitigation service was found to be sufficient for the demand nationwide. However, in specific areas such as cities, the demand was higher than the supply. In the case of water provision service, the national demand was being met by some regional suppliers. Through these results, it is possible to find out the ecosystem services that need to be supplemented spatially and regionally, and ultimately, it is expected to support the establishment of urban space, green space, and environmental planning at the regional and national levels.

OBJECTIVES: America’s overdose crisis spurred rapid expansion in the number and scope of prescription drug monitoring programs (PDMPs). As their public health impact remains contested, little is known about PDMP user experiences and perspectives. We explore perspectives of PDMP end-users in Massachusetts. METHODS: Between 2016–2017, we conducted semi-structured qualitative interviews on overdose crisis dynamics and PDMP experiences with a purposive sample of 18 stakeholders (prescribers, pharmacists, law enforcement, and public health regulators). Recordings were transcribed and double-coded using a grounded hermeneutic approach. RESULTS: Perspectives on prescription monitoring as an element of overdose crisis response differed across sectors, but narratives often critiqued PDMPs as poorly conceived to serve end-user needs. Respondents indicated that PDMP: 1) lacked clear orientation towards health promotion; 2) was not optimally configured or designed as a decision support tool, resulting in confusion over interpreting data to guide health care or law enforcement actions; and, 3) problematized communication and relationships between prescribers, pharmacists, and patients. CONCLUSION: User insights must inform design, programmatic, and policy reform to maximize PDMP benefits while minimizing harm. Their collateral impact may be compounded by COVID-19.

As climate change progresses, the form of forests has been changing. Developmental studies of remote sensing methods are needed to accurately estimate the changing form of forests. Recently, studies for estimating the forest vegetation height of forest area using Landsat data have been actively conducted. Therefore, this study calculated the SLAVI index composed of 4 (red), 5 (NIR), 7 (SWIR2) band combinations of Landsat 8. The relationship between the height of trees was estimated by linear regression analysis. Based on the result, a comparison in the height of the forest stands measured by the National Forest Inventory (NFI) shows a very high accuracy by the height of trees over 9 meters. The applicability of the study was investigated with the results, and the accuracy of the study will be compared through field surveys. The estimated accuracy of the height of trees in this study is not as high as 0.5-0.6 (R2), but it has an advantage of low cost and less effort to estimate the ​​height of trees in a large area and to acquire image data easily. Information about the height of trees is an important parameter for estimating forest biomass and carbon stocks, which is significant in studies of forest under climate change.

We investigated the effect of Mg 2+ on calcite hillock growth over a broad range of solution conditions in terms of supersaturation (Ω calcite ) and Mg/Ca ratios using atomic force microscopy and secondary ion mass spectrometry. We found that both the incorporation pattern/incorporated Mg 2+ quantity in the hillock structure and the Mg 2+ -induced morphological change of the hillock surface showed strong dependence of the growth conditions. Specifically, when Mg/Ca was high (i.e., >5) and Ω calcite was low (i.e., ~0.45), Mg 2+ was predominantly incorporated into the negative sectors of the hillock structure, resulting in gradual loss of step structure and morphological amorphism on these vicinal surfaces. When Mg/Ca and Ω calcite were in intermediate ranges (i.e., Mg/Ca calcite calcite were high (i.e., Mg/Ca > 5, and Ω calcite > 1.1), the growing hillocks experienced two phases of morphological changes, initiated with the formation of “tear-drops” followed by the development of linear ruptures along [481] and [441] directions. And the occurrence of these ruptures segmented the hillock surface effectively into multiple isolated plateaus. Significantly, we revealed the underlying mechanisms for these condition-specific effects of Mg 2+ on calcite growth, which mainly resulted from the interplay among three major factors: (1) the size-mismatch between Mg 2+ and Ca 2+ that causes structural strains in magnesian calcite and leads to morphological amorphism in high-Mg carbonate; (2) the asymmetry of the calcite crystal structure that sets a physical limitation for Mg 2+ incorporation patterns in the hillock structure; and (3) the step advancing rate (i.e., the calcite growth kinetics) that affects both Mg 2+ incorporation and the accommodation of Mg 2+ -induced structural strains in the hillock structure. Detailed discussions were given for each growth scenario. The results of our study provide a theoretical base to decipher the roles of Mg 2+ in CaCO 3 mineralization, and thus, have important implication for a range of processes that involve the growth of Mg-Ca-CO 3 systems, such as biomineralization, carbon capture and storage, and scale controls in industrial settings.

Heteroepitaxial BiFeO 3 thick films were prepared on (100) LaAlO 3 substrates using magnetron sputtering. The sputtering atmosphere, i.e. Ar/O 2 flow ratio, showed significant influence on the charge transport behaviors of BiFeO 3 films. The distinct current density–electric field (J–E) characteristics of films were fitted to three charge transport models: ionic conduction, Schottky emission, and space-charge-limited-current (SCLC). These models were verified by an Auger depth profiling study, which revealed the chemical compositions of the films across their thicknesses. The apparent flow ratio dependence of charge transport in these films is well explained by the models with the supporting Auger data.

The effect of magnesium on calcite growth morphology was known to occur as step rounding in some cases and surface segmentation in others. What remains unknown are the conditions for and the relations between the different effects, suggesting a lack of comprehensive understanding of the fundamental cause. Here we investigated the evolution of spiral hillock morphology on calcite cleavage surfaces in solutions with increasing Ca to Mg ratios and supersaturation levels using in situ atomic force microscopy. We isolated the effects of Mg and saturation by conducting experiments under conditions of constant pH, ionic strength, and Ca 2+ /CO 3 2− . Our results revealed three types of morphological variations, ranging from step rounding in one direction (type I), to all directions (type II), and finally to a mosaic-like surface segmentation associated with monolayer buckling and step bunching (type III). These results suggest that the effect of magnesium on calcite growth depends upon multiple parameters including the concentration of Mg in solution, the step speed, as well as the extensiveness of Mg for Ca substitution in calcite lattice. We propose that the morphological variation may be understood by a model taken into consideration of (1) the lifespan and flux size of Mg ions at kinks in comparison to step kinetics, and (2) the diffusion and alignment of point defects created by the substitution of Mg for Ca in the crystal lattice. Stress calculations show that the maximum amount of Mg which calcite lattice can sustain before plastic deformation is ∼40%, suggesting that lattice stress due to the mismatch between MgCO 3 and CaCO 3 is likely the ultimate cause for the difficulty of ambient condition dolomite crystallization.

The use of superparamagnetic iron oxide nanoparticles (SPIONs) has gained increasing attention in the scientific community with experimental success recorded in medical science through magnetic hyperthermia in cancer treatment and targeted drug delivery. Determining how the nanoparticles and their capping agents react with their surroundings is imperative to optimizing treatments as well as researching new applications for inductively heated nanoparticles. Suspensions of iron oxide nanoparticles capped with TX-100 were prepared in both deionized (DI) water and saline solutions to create a comparison study. The samples were heated via induction, followed by TEM characterization and diffraction pattern analysis for the particles removed after exposure to the high-frequency oscillating magnetic fields. Additional characterization was performed with dynamic light scattering (DLS), magnetic force microscopy (MFM), and X-ray photoelectron spectroscopy (XPS), for determining subsequent changes in their colloidal properties, magnetic interaction, and composition. The introduction of a saline environment promoted clustering, of which its appearance was unique from the DI suspension. This clustering accompanied an increased specific absorption rate for the suspension; moreover, smaller nanoparticles were also observed around the exterior of the clusters. The change in the agglomeration of the nanoparticles within the saline suspensions, and knowledge of previous research into the behavior of TX-100 in the presence of electrolytes, suggests that the addition of sodium chloride salt brought about a chemical change within the samples. MFM measurements show that the particle clusters within the saline suspensions possess higher magnetic attractive forces, and when coupled with the calorimetric measurements gathered, it can be concluded that this positively affected the nanoparticles’ heat output. Such implications and conclusions found will prove useful in optimizing nanoparticle heating for applications such as magnetic hyperthermia.

We investigated the roles of three proteins associated with the formation of otoconia including fetuin A, osteopontin (OPN), and otoconin 90 (OC90). In situ atomic force microscopy (AFM) studies of the effects of these proteins on the growth of atomic steps on calcite surfaces were performed to obtain insight into their effects on the growth kinetics. We also used scanning electron microscopy to examine the effects of these proteins on crystal morphology. All three proteins were found to be potent inhibitors of calcite growth, although fetuin A promoted growth at concentrations below about 40 nM and only became an inhibitor at higher concentrations. We then used in situ optical microscopy to observe calcite nucleation on films of these proteins adsorbed onto mica surfaces. By measuring the calcite nucleation rate as a function of supersaturation, the value of the interfacial energy that controls the free energy barrier to heterogeneous nucleation was determined for each protein. OPN and OC90 films led to significantly reduced interfacial energies as compared to the value for homogeneous calcite nucleation in bulk solution. The value for fetuin A was equal to that for bulk solution within experimental error. Zeta potential measurements showed all of the proteins possessed negative surface charge and varied in magnitude according to sequence fetuin A > OC90 > OPN. In addition, the interfacial energies exhibited an inverse scaling with the zeta potential. In analogy to previous measurements on polysaccharide films, this scaling indicates the differences between the proteins arise from the effect of protein surface charge on the solution–substrate interfacial energy., We investigated effects of three otoconial proteins on calcite growth kinetics by in situ atomic force microscopy and on crystal morphology by scanning electron microscopy. We used in situ optical microscopy to determine the free energy barriers and interfacial energies controlling calcite nucleation on films of the proteins. The results were rationalized through zeta potential measurements relating surface charge to solution−substrate interfacial energy for each protein.

Classical crystallization models successfully depict the dependence of growth kinetics on thermodynamic driving force but cannot predict the roles of solution chemistry. Yet, it has become increasingly clear that crystal growth rate at fixed supersaturations depends on pH, ionic strength, and the relative abundance of cations and anions in the parent solutions. We conducted experiments to isolate the effect of individual solution-chemistry parameters on calcite step growth kinetics. Our results revealed a distinct correlation between step velocity and pH in acute and obtuse directions and a simultaneous trend change at pH ∼9.5. Step speeds varied with solution stoichiometry, and each direction reached its maximal rate at a different [ Ca 2 + ] / [ CO 3 2 - ] value. In addition, the solution cation/anion at which maximal step speed occurred appeared to be pH dependent as well. Limited effect of ionic strength on step growth was observed in the obtuse direction at low background electrolyte concentrations, but no obvious change was found for growth at the acute side. We proposed a growth model based upon independent incorporation of cations and anions and interpreted these observations as: (1) solute constituents enter kinks through direct solution diffusion at obtuse steps but surface diffusion at acute steps; (2) growth is limited by Ca2+ dehydration at the obtuse side, but by surface adsorption and reorientation and rearrangement of CO32− in the acute direction; and (3) background electrolyte (NaCl in our study) competes with solutes for surface sites at more easily accessible kinks.

Forests play an important role in regulating the carbon (C) cycle. The main objective of this study was to quantify the effects of South Korean national reforestation programs on carbon budgets. We estimated the changes in C stocks and annual C sequestration in the years 1961&ndash, 2014 using Korea-specific models, a forest cover map (FCM), national forest inventory (NFI) data, and climate data. Furthermore, we examined the differences in C budgets between Cool forests (forests at elevations above 700 m) and forests in lower-altitude areas. Simulations including the effects of climate conditions on forest dynamics showed that the C stocks of the total forest area increased from 6.65 Tg C in 1961 to 476.21 Tg C in 2014. The model developed here showed a high degree of spatiotemporal reliability. The mean C stocks of the Cool forests and other forests increased from 4.03 and 0.43 Mg C ha&minus, 1, respectively, to 102.43 and 73.76 Mg C ha&minus, 1 at a rate of 1.82 and 1.36 Mg C ha&minus, 1 yr&minus, 1 during the same period. These results imply that, although the total Cool forest area of South Korea occupied only about 12.3% (772,788 ha) of the total forest area, the Cool forests play important roles in C balances and forest ecosystems in South Korea. Annual C sequestration totals are projected to decrease at a low rate in the near future because the overall growth rate of a mature forest decreases as the stand ages. Our results quantified forest C dynamics in South Korean forests before and after national reforestation programs. Furthermore, our results can help in development of regional and national forest management strategies to allow for sustainable development of society and to cope with climate change in South Korea.

Background: The neural crest (NC) is a multipotent embryonic cell population, which is induced by an integration of secreted signals including BMP, Wnt, and FGF and, subsequently, NC cell fates are specified by a regulatory network of specific transcription factors. This study was undertaken to identify a role of Sp5 transcription factor in vertebrates. Results: Xenopus Sp5 is expressed in the prospective neural crest regions from gastrulation through the tadpole stages in early development. Knockdown of Sp5 caused severe defects in craniofacial cartilage, pigmentation, and dorsal fin. Gain- and loss-of-function of Sp5 led to up- and down-regulation of the expression of NC markers in the neural fold, respectively. In contrast, Sp5 had no effect on neural induction and patterning. Sp5 regulated the expression of neural plate border (NPB) specifiers, Msx1 and Pax3, and these regulatory factors recovered the expression of NC marker in the Sp5-deficient embryos. Depletion of Sp5 impaired NC induction by Wnt/β-catenin or FGF signal, whereas its co-expression rescued NC markers in embryos in which either signal was blocked. Conclusions: These results suggest that Sp5 functions as a critical early factor in the genetic cascade to regulate NC induction downstream of Wnt and FGF pathways. Developmental Dynamics 242:1382–1394, 2013. © 2013 Wiley Periodicals, Inc.

Efficient cell corpse clearance is critical for health in organisms. Apoptotic cells displaying phosphatidylserine (PS) are recognized by engulfment receptors and ingested through two conserved pathways. In one pathway, engulfment receptor brain-specific angiogenesis inhibitor 1 (BAI-1) or integrin functions upstream of ELMO/DOCK180 and activate the small GTPase Rac1. In the other pathway, engulfment receptor CED-1 or stabilin-2 acts in concert with the adaptor protein GULP to activate Rac1. Stabilin-2, a PS receptor, facilitates phagocytosis of apoptotic cells and mediates the production of anti-inflammatory cytokines. Here, we propose that the stabilin-2 extracellular domain consisting of integrin-binding fasciclin 1 (FAS1) domains coordinates the activities of the two phagocytic pathways via direct interactions with integrin. Interactions between stabilin-2 and integrin were determined using biochemical assays, including coimmunoprecipitation and fluorescence resonance energy transfer (FRET). These interactions appear to have functional relevance, since knockdown of endogenous αvβ5 expression or treatment with a function-blocking αvβ5 antibody significantly decreased stabilin-2-mediated phagocytosis in the absence of soluble factors. Our data collectively suggest that the engulfment receptors of the two phagocytic pathways communicate with each other to orchestrate engulfment of damaged erythrocytes. Coordinated phagocytic signaling would be advantageous for physiological and pathological circumstances that require rapid clearance of abnormal (apoptotic or aged) cells.

Clearance of apoptotic cells is involved in the resolution of inflammation, and this mechanism is controlled by the regulation of pro- and anti-inflammatory cytokine production during the ingestion of apoptotic cells. Inflamed areas show extracellular acidity, and low pH stimulates cellular functions of immune cells. However, little is known about the influence of extracellular acidic pH on the function of phagocytic cells. In this study, we showed that stabilin-2-mediated phagocytosis is activated in low pH media (pH 6.8) and examined the molecular mechanisms underlying this pH-dependent enhancement of phagocytic activity. Stabilin-2, which is expressed in human monocyte derived macrophages (HMDM), is a phosphatidylserine (PS) receptor that mediates phagocytosis of apoptotic cells, and releases the anti-inflammatory cytokine, TGF-β. The PS binding activity of stabilin-2 is enhanced in low pH, and a conserved histidine1403 in close proximity to the PS binding loop is critical for pH-dependent activity. We propose that protonation of His1403 may rearrange the PS binding loop to enhance binding affinity in low pH, indicating that acidic pH might act as a danger signal to stimulate stabilin-2-mediated phagocytosis to resolve inflammation. Considering that phosphatidylserine is an important target molecule for apoptotic cells in the acidic microenvironment of inflammation and tumors, our results also have implications for pH sensitive targeting of apoptotic cells.

Objective To describe the extent of pharmacy detection and monitoring of medication non-adherence, and solutions offered to improve adherence. Methods Participants were 60 residents of the Boston area who had a generic chronic medication with 30 day supplies from their usual pharmacy. Participants received a duplicate prescription which they filled at a different pharmacy. For 5 months, participants alternated between the two pharmacies, creating gaps in their refill records at both pharmacies but no gaps in their medication adherence. Participants followed a scripted protocol and after each pharmacy visit reported their own and the pharmacy staff’s behavior. Results Across 78 unique community pharmacies and 260 pharmacy visits, pharmacies were inconsistent and inadequate in asking if participants had questions, discussing the importance of adherence, providing adequate consultations with new medication, and detecting and intervening on non-adherence. Insurers rarely contacted the participants about adherence concerns. Conclusion There is a need for more structured intervention systems to ensure pharmacists are consistently and adequately educating patients and detecting/managing potential medication non-adherence. Practice Implications The present study calls for more attention to building infrastructure in pharmacy practice that helps pharmacists more consistently identify, monitor, and intervene on medication adherence.

The use of an argon cluster ion sputtering source has been demonstrated to perform superiorly relative to traditional oxygen and cesium ion sputtering sources for ToF-SIMS depth profiling of insulating materials. The superior performance has been attributed to effective alleviation of surface charging. A simulated nuclear waste glass (SON68) and layered hole-perovskite oxide thin films were selected as model systems because of their fundamental and practical significance. Our results show that high sputter rates and accurate interfacial information can be achieved simultaneously for argon cluster sputtering, whereas this is not the case for cesium and oxygen sputtering. Therefore, the implementation of an argon cluster sputtering source can significantly improve the analysis efficiency of insulating materials and, thus, can expand its applications to the study of glass corrosion, perovskite oxide thin film characterization, and many other systems of interest.

Otoconia are formed embryonically and are instrumental in detecting linear acceleration and gravity. Degeneration and fragmentation of otoconia in elderly patients leads to imbalance resulting in higher frequency of falls that are positively correlated with the incidence of bone fractures and death. In this work we investigate the roles otoconial proteins Otolin-1 and Otoconin 90 (OC90) perform in the formation of otoconia. We demonstrate by rotary shadowing and atomic force microscopy (AFM) experiments that Otolin-1 forms homomeric protein complexes and self-assembled networks supporting the hypothesis that Otolin-1 serves as a scaffold protein of otoconia. Our calcium carbonate crystal growth data demonstrate that Otolin-1 and OC90 modulate in vitro calcite crystal morphology but neither protein is sufficient to produce the shape of otoconia. Coadministration of these proteins produces synergistic effects on crystal morphology that contribute to morphology resembling otoconia.

The Wnt/β-catenin signaling pathway plays critical roles in early embryonic development, stem cell biology and human diseases including cancers. Although Rap2, a member of Ras GTPase family, is essential for the Wnt/β-catenin pathway during the body axis specification in Xenopus embryo, the mechanism underlying its regulation of Wnt signaling remains poorly understood. Here, we show that Rap2 is implicated in control of the stability of Wnt receptor, low-density lipoprotein receptor-related protein 6 (LRP6). Knockdown of Rap2 resulted in the proteasome and/or lysosome-dependent degradation of LRP6 both in the presence and absence of Wnt ligand stimulation. In line with this, constitutively active LRP6 lacking its extracellular domain, which is constitutively phosphorylated and resides in intracellular vesicles, was also degraded in the Rap2-silenced cells. In addition, Rap2 and LRP6 associated physically with each other. Furthermore, we found that TRAF2/Nck-interacting kinase (TNIK), a member of the Ste20 protein family, acts as a downstream effector of Rap2 in control of LRP6 stabilization. Consistently, TNIK could rescue the inhibitory effects of Rap2 depletion on Wnt-dependent gene transcription, reporter activation and neural crest induction. Taken together, these results suggest that Rap2 acts via TNIK to regulate the stability of LRP6 receptor for Wnt/β-catenin signaling.

The neural crest (NC) is a multipotent embryonic cell population, which is induced by an integration of secreted signals including BMP, Wnt, and FGF and, subsequently, NC cell fates are specified by a regulatory network of specific transcription factors. This study was undertaken to identify a role of Sp5 transcription factor in vertebrates.Xenopus Sp5 is expressed in the prospective neural crest regions from gastrulation through the tadpole stages in early development. Knockdown of Sp5 caused severe defects in craniofacial cartilage, pigmentation, and dorsal fin. Gain- and loss-of-function of Sp5 led to up- and down-regulation of the expression of NC markers in the neural fold, respectively. In contrast, Sp5 had no effect on neural induction and patterning. Sp5 regulated the expression of neural plate border (NPB) specifiers, Msx1 and Pax3, and these regulatory factors recovered the expression of NC marker in the Sp5-deficient embryos. Depletion of Sp5 impaired NC induction by Wnt/β-catenin or FGF signal, whereas its co-expression rescued NC markers in embryos in which either signal was blocked.These results suggest that Sp5 functions as a critical early factor in the genetic cascade to regulate NC induction downstream of Wnt and FGF pathways.

Isolation and structures of two novel neolignans, asatone (1) and isoasatone (2), are described. The structure of the latter, established by means of an X-ray crystallographic analysis of its dihydroxy derivative, is in full agreement with its chemical and spectral data. From a biogenetic point of view, furthermore, thermal and photochemical reactions of these neolignans and their derivatives were carried out. In particular,asatone was photochemically converted into isoasatone.

In den beiden Arbeiten werden Struktur und Umwandlungsreaktion von Isoasaton (I) beschrieben.

Isolation and structures of two novel neolignans, asatone (1) and isoasatone (2), are described. The structure of the latter, established by means of an X-ray crystallographic analysis of its dihydroxy derivative, is in full agreement with its chemical and spectral data. From a biogenetic point of view, furthermore, thermal and photochemical reactions of these neolignans and their derivatives were carried out. In particular,asatone was photochemically converted into isoasatone.