Sphagnum farming on cut-over bog in NW Germany: Long-term studies on Sphagnum growth

Sphagnum farming allows sustainable and climate-friendly land use on bogs while producing a renewable substitute for peat in horticultural growing media. We studied Sphagnum productivity on an experimental Sphagnum culture established on a cut-over bog in Germany with strongly humified peat at the surface. Preparation of the site included levelling of the peat surface, construction of an irrigation system, spreading of Sphagnum papillosum fragments, covering them with straw, and finally rewetting. Provided there was an adequate (95 %) initial cover of Sphagnum fragments, the most relevant variables for Sphagnum productivity were found to be water supply and regular mowing of vascular plants. As long as sufficient water was supplied, the dry biomass accumulation of the established Sphagnum lawn remained high, reaching 3.7 t ha-1 yr-1 between 2007 and 2011. Annual dry Sphagnum biomass productivity over the period 2010–2011 was up to 6.9 t ha-1. During periods when high water table could not be maintained, substantial decomposition of the previously accumulated biomass occurred. After nine years the net accumulated dry mass per hectare was on average 19.5 t of pure Sphagnum and 0.7 t of subsurface vascular-plant biomass. Nitrogen deposition in the study region is apparently sufficient to support fast Sphagnum growth, whereas phosphorus and potassium may be limiting

Sphagnum regrowth after cutting

Sphagnum biomass is commercially harvested from semi-natural and natural peatlands. In this article we analyse the effects of harvesting Sphagnum by cutting off the top parts of the plants and leaving the cut stems to regenerate. We tested regrowth of Sphagnum palustre and Sphagnum papillosum in natural peatlands with high Sphagnum productivity in Kolkheti (Georgia, Transcaucasus) using two cutting depths (5, 10 cm) and two cutting intervals (1, 2 years). In Germany we measured regrowth of S. papillosum in an experimental Sphagnum farming field 2.5 years after cutting off the top 5 cm. Regrowth of Sphagnum was similar in both regions, with new capitula attaining 80 % cover one year after cutting and similar biomass productivities (Kolkheti: S. palustre 169–329 g m-2 yr-1, S. papillosum 152–246 g m-2 yr-1; Germany: S. papillosum 249 g m 2 yr-1). In Kolkheti, regrowth was independent of cutting depth. No relationship between site conditions and biomass regrowth was identified in either Kolkheti or Germany, probably because of the overarching effect of favourable hydrological conditions. This study shows that cutting is an appropriate method for harvesting Sphagnum and allows repeated harvests with fast Sphagnum regrowth. For S. palustre, it may even be possible to harvest annually without reducing yields

Differences in single and aggregated nanoparticle plasmon spectroscopy

Vibrational spectroscopy usually provides structural information averaged over many molecules. We report a larger peak position variation and reproducibly smaller FWHM of TERS spectra compared to SERS spectra indicating that the number of molecules excited in a TERS experiment is extremely low. Thus, orientational averaging effects are suppressed and micro ensembles are investigated. This is shown for a thiophenol molecule adsorbed on Au nanoplates and nanoparticles

Overcoming establishment thresholds for peat mosses in human-made bog pools

Globally, peatlands have been affected by drainage and peat extraction, with adverse effects on their functioning and services. To restore peat‐forming vegetation, drained bogs are being rewetted on a large scale. Although this practice results in higher groundwater levels, unfortunately it often creates deep lakes in parts where peat was extracted to greater depths than the surroundings. Revegetation of these deeper waters by peat mosses appears to be challenging due to strong abiotic feedbacks that keep these systems in an undesired bare state. In this study, we theoretically explore if a floating peat mat and an open human‐made bog lake can be considered two alternative stable states using a simple model, and experimentally test in the field whether stable states are present, and whether a state shift can be accomplished using floating biodegradable structures that mimic buoyant peat. We transplanted two peat moss species into these structures (pioneer sp. Sphagnum cuspidatum and later‐successional sp. S. palustre) with and without additional organic substrate. Our model suggests that these open human‐made bog lakes and floating peat mats can indeed be regarded as alternative stable states. Natural recovery by spontaneous peat moss growth, i.e., a state shift from open water to floating mats, is only possible when the water table is sufficiently shallow to avoid light limitation (<0.29 m at our site). Our experiment revealed that alternative stable states are present and that the floating structures facilitated the growth of pioneer S. cuspidatum and vascular plants. Organic substrate addition particularly facilitated vascular plant growth, which correlated to higher moss height. The structures remained too wet for the late‐successional species S. palustre. We conclude that open water and floating peat mats in human‐made bog lakes can be considered two alternative stable states, and that temporary floating establishment structures can induce a state shift from the open water state to peat‐forming vegetation state. These findings imply that for successful restoration, there is a clear water depth threshold to enable peat moss growth and there is no need for addition of large amounts of donor‐peat substrate. Correct species selection for restoration is crucial for success

Atomic-scale confinement of optical fields

In the presence of matter there is no fundamental limit preventing confinement of visible light even down to atomic scales. Achieving such confinement and the corresponding intensity enhancement inevitably requires simultaneous control over atomic-scale details of material structures and over the optical modes that such structures support. By means of self-assembly we have obtained side-by-side aligned gold nanorod dimers with robust atomically-defined gaps reaching below 0.5 nm. The existence of atomically-confined light fields in these gaps is demonstrated by observing extreme Coulomb splitting of corresponding symmetric and anti-symmetric dimer eigenmodes of more than 800 meV in white-light scattering experiments. Our results open new perspectives for atomically-resolved spectroscopic imaging, deeply nonlinear optics, ultra-sensing, cavity optomechanics as well as for the realization of novel quantum-optical devices

Results of an Early Access Treatment Protocol of Daratumumab Monotherapy in Spanish Patients With Relapsed or Refractory Multiple Myeloma

Daratumumab is a human CD38-targeted monoclonal antibody approved as monotherapy for heavily pretreated relapsed and refractory multiple myeloma. We report findings for the Spanish cohort of an open-label treatment protocol that provided early access to daratumumab monotherapy and collected safety and patient-reported outcomes data for patients with relapsed or refractory multiple myeloma. At 15 centers across Spain, intravenous daratumumab (16 mg/kg) was administered to 73 patients who had >= 3 prior lines of therapy, including a proteasome inhibitor and an immunomodulatory drug, or who were double refractory to both. The median duration of daratumumab treatment was 3.3 (range: 0.03-13.17) months, with a median number of 12 (range: 1-25) infusions. Grade 3/4 treatment-emergent adverse events were reported in 74% of patients and included lymphopenia (28.8%), thrombocytopenia (27.4%), neutropenia (21.9%), leukopenia (19.2%), and anemia (15.1%). Common (>5%) serious treatmentemergent adverse events included respiratory tract infection (9.6%), general physical health deterioration (6.8%), and back pain (5.5%). Infusion-related reactions occurred in 45% of patients. The median change from baseline in all domains of the EQ-5D-5L and EORTC QLQ-C30 was mostly 0. A total of 18 (24.7%) patients achieved a partial response or better, with 10 (13.7%) patients achieving a very good partial response or better. Median progression-free survival was 3.98 months. The results of this early access treatment protocol are consistent with previously reported trials of daratumumab monotherapy and confirm its safety and antitumoral efficacy in Spanish patients with heavily treated relapsed or refractory multiple myeloma

Daratumumab Monotherapy for Relapsed or Refractory Multiple Myeloma: Results of an Early Access Treatment Protocol in Europe and Russia

Introduction Daratumumab is a human IgGκ monoclonal antibody targeting CD38. Despite the demonstrated benefit of daratumumab in multiple myeloma, not all patients have access to commercially available daratumumab. Here we report a pooled analysis of patients from the UK, Spain, Italy, and Russia enrolled in an open-label, early access treatment protocol (EAP) that provided daratumumab (16 mg/kg) monotherapy to patients with heavily pre-treated relapsed or refractory multiple myeloma (RRMM). Methods Intravenous daratumumab 16 mg/kg was administered to patients who had received ≥ 3 prior lines of therapy, including a proteasome inhibitor (PI) and an immunomodulatory drug (IMiD), or who were double refractory to both a PI and an IMiD. Safety and patient-reported outcomes data were collected. Results A total of 293 patients received  ≥ 1 dose of daratumumab. The median duration of daratumumab exposure was 4.2 (range 0.03–24.1) months, with a median number of 13 (range 1–37) infusions. The overall response rate was 33.1%, and the median progression-free survival was 4.63 months. Grade 3/4 treatment-emergent adverse events occurred in 60.1% of patients, of which the most common were thrombocytopenia (18.8%), anemia (11.9%), and neutropenia (11.6%). The most common serious adverse events were pneumonia (4.4%) and pyrexia (4.1%). Infusion-related reactions occurred in 45.1% of patients. The median change from baseline in all domains of patient-reported outcome instruments (European Quality of Life Five Dimensions Questionnaire [EQ-5D–5L], European Organisation for Research and Treatment of Cancer [EORTC] Quality of Life Questionnaire [QLQ-C30], and EORTC Multiple Myeloma Module [QLQ-MY20]) was generally 0 or close to 0. Conclusion These EAP results are consistent with those from previous trials of daratumumab monotherapy and confirm its safety in patients from Europe and Russia with heavily pre-treated RRMM. Trial Registration ClinicalTrials.gov identifier, NCT02477891