Not only the butterflies: managing ants on road verges to benefit Phengaris (Maculinea) butterflies

Obligate myrmecophilic butterfly species, such as Phengaris (Maculinea) teleius and P. nausithous, have narrow habitat requirements. Living as a caterpillar in the nests of the ant species Myrmica scabrinodis and M. rubra, respectively, they can only survive on sites with both host ants and the host plant Great Burnet Sanguisorba officinalis. After having been reintroduced into a nature reserve in the Netherlands in 1990, both butterfly species expanded their distribution to linear landscape elements such as road verges and ditch edges outside this reserve. As additional habitat of both butterfly species, vegetation management of these landscape elements became important. Our results show that a management beneficial for Phengaris butterflies should aim to increase the nest density of Myrmica species, at the same time reducing the density of nests of the competitor Lasius niger or at least keeping them at a low density. Unfavourable grassland management under which L. niger thrives, includes not mowing or flail-cutting the grass, or depositing dredgings along the side of the ditch. Management favourable for the two Myrmica species differs, demanding some flexibility if both species are to benefit. M. scabrinodis is best supported with early mowing of the road verge vegetation or late mowing in the nature reserve, both of which result in an open vegetation and warm microclimate. In contrast, the nest sites of M. rubra should be left undisturbed during the summer, and mown in late autumn. Mowing of butterfly habitat should be avoided between mid-June and mid-September as this would remove the flowerheads of the Sanguisorba plants, on which the butterflies lay their eggs

The Incidence of Antibody-Mediated Rejection Is Age-Related, Plateaus Late After Kidney Transplantation, and Contributes Little to Graft Loss in the Older Recipients

It is not known whether antibody-mediated rejection (ABMR) is age-related, whether it plateaus late after transplantation, and to what extent it contributes to graft loss in older recipients. Patients transplanted between 2010 and 2015 (n = 1,054) in a single center had regular follow-up until January 2023. Recipients were divided into age groups at transplantation: 18-39 years ("young"), 40-55 years ("middle age"), and >55 years ("elderly"). Ten years after transplantation the cumulative % of recipients with ABMR was 17% in young, 15% in middle age, and 12% in elderly recipients (p < 0.001). The cumulative incidence of ABMR increased over time and plateaued 8-10 years after transplantation. In the elderly, with a median follow-up of 7.5 years, on average 30% of the recipients with ABMR died with a functional graft and ABMR contributed only 4% to overall graft loss in this group. These results were cross-validated in a cohort of recipients with >15 years follow-up. Multivariate cox-regression analysis showed that increasing recipient age was independently associated with decreasing risk for ABMR. In conclusion, the cumulative risk for ABMR is age-dependent, plateaus late after transplantation, and contributes little to overall graft loss in older recipients

Measurement of the Neutron Lifetime by Counting Trapped Protons in a Cold Neutron Beam

A measurement of the neutron lifetime $\tau_{n}$ performed by the absolute counting of in-beam neutrons and their decay protons has been completed. Protons confined in a quasi-Penning trap were accelerated onto a silicon detector held at a high potential and counted with nearly unit efficiency. The neutrons were counted by a device with an efficiency inversely proportional to neutron velocity, which cancels the dwell time of the neutron beam in the trap. The result is $\tau_{n} = (886.6\pm1.2{\rm [stat]}\pm3.2{\rm [sys]})$ s, which is the most precise measurement of the lifetime using an in-beam method. The systematic uncertainty is dominated by neutron counting, in particular the mass of the deposit and the $^{6}$Li({\it{n,t}}) cross section. The measurement technique and apparatus, data analysis, and investigation of systematic uncertainties are discussed in detail.Comment: 71 pages, 20 figures, 9 tables; submitted to PR

Metal transfer to sediments, invertebrates and fish following waterborne exposure to silver nitrate or silver sulfide nanoparticles in an indoor stream mesocosm.

The fate of engineered nanomaterials in ecosystems is unclear. An aquatic stream mesocosm was explored the fate and bioaccumulation of silver sulfide nanoparticles (Ag2S NPs) compared to silver nitrate (AgNO3). The aims were to determine the total Ag in water, sediment and biota, and to evaluate the bioavailable fractions of silver in the sediment using a serial extraction method. The total Ag in the water column from a nominal daily dose of 10 μg L-1 of Ag for the AgNO3 or Ag2S NP treatments reached a plateau of around 13 and 12 μg L-1, respectively, by the end of the study. Similarly, the sediment of both Ag-treatments reached ~380 μg Ag kg-1, and with most of it being acid-extractable/labile. The biota accumulated 4-59 μg Ag g-1 dw, depending on the type of Ag-treatment and organism. The oligochaete worm, Lumbriculus variegatus, accumulated Ag from the Ag2S exposure over time, which was similar to the AgNO3 treatment by the end of the experiment. The planarian, Girardia tigrina, and the chironomid larva, Chironomus riparius, showed much higher Ag concentrations than the oligochaete worms; and with a clearer time-dependent statistically significant Ag accumulation relative to the untreated controls. For the pulmonated snail, Physa acuta, bioaccumulation of Ag from AgNO3 and Ag2S NP exposures was observed, but was lower from the nano treatment. The AgNO3 exposure caused appreciable Ag accumulation in the water flea, Daphnia magna, but accumulation was higher in the Ag2S NP treatment (reaching 59 μg g-1 dw). In the rainbow trout, Oncorhynchus mykiss, AgNO3, but not Ag2S NPs, caused total Ag concentrations to increase in the tissues. Overall, the study showed transfer of total Ag from the water column to the sediment, and Ag bioaccumulation in the biota, with Ag from Ag2S NP exposure generally being less bioavailable than that from AgNO3

Alternative Living Kidney Donation Programs Boost Genetically Unrelated Donation

Donor-recipient ABO and/or HLA incompatibility used to lead to donor decline. Development of alternative transplantation programs enabled transplantation of incompatible couples. How did that influence couple characteristics? Between 2000 and 2014, 1232 living donor transplantations have been performed. In conventional and ABO-incompatible transplantation the willing donor becomes an actual donor for the intended recipient. In kidney-exchange and domino-donation the donor donates indirectly to the intended recipient. The relationship between the donor and intended recipient was studied. There were 935 conventional and 297 alternative program transplantations. There were 66 ABO-incompatible, 68 domino-paired, 62 kidney-exchange, and 104 altruistic donor transplantations. Waiting list recipients (n=101) were excluded as they did not bring a living donor. 1131 couples remained of whom 196 participated in alternative programs. Genetically unrelated donors (486) were primarily partners. Genetically related donors (645) were siblings, parents, children, and others. Compared to genetically related couples, almost three times as many genetically unrelated couples were incompatible and participated in alternative programs (P<0.001). 62% of couples were genetically related in the conventional donation program versus 32% in alternative programs (P<0.001). Patient and graft survival were not significantly different between recipient programs. Alternative donation programs increase the number of transplantations by enabling genetically unrelated donors to donate

Involvement of Complexin 2 in Docking, Locking and Unlocking of Different SNARE Complexes during Sperm Capacitation and Induced Acrosomal Exocytosis

Acrosomal exocytosis (AE) is an intracellular multipoint fusion reaction of the sperm plasma membrane (PM) with the outer acrosomal membrane (OAM). This unique exocytotic event enables the penetration of the sperm through the zona pellucida of the oocyte. We previously observed a stable docking of OAM to the PM brought about by the formation of the trans-SNARE complex (syntaxin 1B, SNAP 23 and VAMP 3). By using electron microscopy, immunochemistry and immunofluorescence techniques in combination with functional studies and proteomic approaches, we here demonstrate that calcium ionophore-induced AE results in the formation of unilamellar hybrid membrane vesicles containing a mixture of components originating from the two fused membranes. These mixed vesicles (MV) do not contain the earlier reported trimeric SNARE complex but instead possess a novel trimeric SNARE complex that contained syntaxin 3, SNAP 23 and VAMP 2, with an additional SNARE interacting protein, complexin 2. Our data indicate that the earlier reported raft and capacitation-dependent docking phenomenon between the PM and OAM allows a specific rearrangement of molecules between the two docked membranes and is involved in (1) recruiting SNAREs and complexin 2 in the newly formed lipid-ordered microdomains, (2) the assembly of a fusion-driving SNARE complex which executes Ca2+-dependent AE, (3) the disassembly of the earlier reported docking SNARE complex, (4) the recruitment of secondary zona binding proteins at the zona interacting sperm surface. The possibility to study separate and dynamic interactions between SNARE proteins, complexin and Ca2+ which are all involved in AE make sperm an ideal model for studying exocytosis

A model of impairment and functional limitation in rheumatoid arthritis

BACKGROUND: We have previously proposed a theoretical model for studying physical disability and other outcomes in rheumatoid arthritis (RA). The purpose of this paper is to test a model of impairment and functional limitation in (RA), using empirical data from a sample of RA patients. We based the model on the disablement process framework. METHODS: We posited two distinct types of impairment in RA: 1) Joint inflammation, measured by the tender, painful and swollen joint counts; and 2) Joint deformity, measured by the deformed joint count. We hypothesized direct paths from the two impairments to functional limitation, measured by the shirt-button speed, grip strength and walking velocity. We used structural equation modeling to test the hypothetical relationships, using empirical data from a sample of RA patients recruited from six rheumatology clinics. RESULTS: The RA sample was comprised of 779 RA patients. In the structural equation model, the joint inflammation impairment displayed a strong significant path toward the measured variables of joint pain, tenderness and swelling (standardized regression coefficients 0.758, 0.872 and 0.512, P ≤ 0.001 for each). The joint deformity impairment likewise displayed significant paths toward the measured upper limb, lower limb, and other deformed joint counts (standardized regression coefficients 0.849, 0.785, 0.308, P ≤ 0.001 for each). Both the joint inflammation and joint deformity impairments displayed strong direct paths toward functional limitation (standardized regression coefficients of -0.576 and -0.564, respectively, P ≤ 0.001 for each), and explained 65% of its variance. Model fit to data was fair to good, as evidenced by a comparative fit index of 0.975, and the root mean square error of approximation = 0.058. CONCLUSION: This evidence supports the occurrence of two distinct impairments in RA, joint inflammation and joint deformity, that together, contribute strongly to functional limitations in this disease. These findings may have implications for investigators aiming to measure outcome in RA