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Background and Purpose: The aim was to determine the value of autologous haematopoietic stem cell transplantation (aHSCT) as a therapeutic intervention for progressive multiple sclerosis (PMS) based on a systematic review of the current literature. Methods: All studies from the databases PubMed and Google Scholar published in English before February 2024 which provided individual data for PMS patients were systematically reviewed. PICO was defined as population (P), primary progressive MS and secondary progressive MS patients; intervention (I), treatment with aHSCT; comparison (C), none, disease‐modifying therapy treated/relapsing–remitting MS cohorts if available; outcome (O), transplant‐related mortality, progression‐free survival (PFS) and no evidence of disease activity. Results: A total of 15 studies met the criteria including 665 patients with PMS (74 primary progressive MS, 591 secondary progressive MS) and 801 patients with relapsing–remitting MS as controls. PFS data were available for 647 patients. PMS patients showed more severe disability at baseline than relapsing–remitting MS patients. The average transplant‐related mortality for PMS in 10 studies was 1.9%, with 10 deaths in 528 patients. PFS ranged from 0% to 78% in PMS groups 5 years after treatment initiation, demonstrating a high variability. No evidence of disease activity scores at 5 years ranged from 0% to 75%. Conclusion: Based on the available data, aHSCT does not halt progression in people with PMS. However, there appears to be evidence of improved outcome in selected patients. Due to the heterogeneity of the available data, more comprehensive clinical trials assessing the efficacy of aHSCT across different patient groups are urgently needed to reduce variability and improve patient stratification. [ABSTRACT FROM AUTHOR]

Objective: Regulation of postprandial (pp) plasma glucose excursions is complex. Insulin and glucagon are thought to play the predominant role. Nevertheless, only 50% of the variation in pp plasma glucose excursions is explained by variations by the latter. Theoretically, gastric emptying (GE) should be another important factor. However, its impact on pp glucose homeostasis is unknown. Research Design and Methods: We examined the consequences of pramlintide-induced delay in GE on pp glycemia and glucose fluxes, determined isotopically. GE was recorded by scintigraphy. Fourteen healthy subjects (8 men, 6 women; age 40 [+ or -] 3 yr, body mass index 27.8 [+ or -] 1.1 kg/[m.sup.2]) ate a mixed meal, and 30 [micro]g of pramlintide (PRAM) or placebo (PBO) were injected subcutaneously. Results: At 60 min, greater proportions of the initial gastric contents remained in the stomach (PBO vs. PRAM). Thereafter, GE slopes paralleled until 240 min. Fifty percent retention times were lower when PBO was given (P < 0.001). GE was greater from 240 min to the end of the PRAM experiments, so that only slightly greater proportions of the meal remained in the stomach at 330 min. Reductions of GE lowered pp glucose (7.5 [+ or -] 0.3 vs. 6.0 [+ or -] 0.2 mmol/1, P < 0.001), even though plasma insulin was lower with PRAM (164 [+ or -] 13 vs. 138 [+ or -] 13 pmol/ml, both P < 0.01). Reduction in total glucose appearance (P < 0.001) was due to reduced meal-derived glucose appearance (10.2 [+ or -] 0.5 vs. 7.0 [+ or -] 0.4 [micro]mol x [kg.sup.-1] x [min.sup.-1], P < 0.001). Endogenous glucose appearance was greater with PRAM (P < 0.001). Splanchnic glucose uptake was greater with PRAM (26.5 [+ or -] 1.6 vs. 32.5 [+ or -] 2.1%, P = 0.014). Conclusions: These data support the concept that GE is an important physiological regulator of pp glucose homeostasis in humans.

BACKGROUND: The presence of TP53 mutations is associated with an unfavorable outcome in patients allografted for acute myeloid leukemia (AML), leading some to question the benefit of an allogeneic stem cell transplantation (allo‐SCT) for this patient group, although this has not been studied in a large cohort. METHODS: A total of 780 patients with AML in first complete remission, with either intermediate‐ or adverse‐risk cytogenetics, whose TP53 mutation status was reported, were included in this study from the European Society for Blood and Marrow Transplantation. RESULTS: Two‐year overall survival (OS) was impaired in patients (n = 179) with evidence of a TP53 mutation at diagnosis (35.1%; 95% confidence interval [CI], 26.7–43.7) as compared to the cohort without (n = 601) (64%; 95% CI, 59.1–68.4; P =.001). In patients with mutant TP53 AML with no evidence of either chromosome 17p loss (17p–) and/or complex karyotype (CK) (n = 53, 29.6%), 2‐year OS was 65.2% (95% CI, 48.4–77.6). This was not significantly different to patients without TP53 mutations. In patients with mutant TP53 AML with either 17p– and/or CK (n = 126, 70.4%), the OS was lower (24.6%; 95% CI, 16.2–34; P =.001). CONCLUSIONS: In summary, the adverse prognostic effect of TP53 mutations in AML following an allo‐SCT is not evident in patients with neither co‐occurring 17p– and/or CK, and these data inform decisions regarding allo‐SCT in patients with TP53 mutant AML. [ABSTRACT FROM AUTHOR]

Melt ponds have a strong impact on the Arctic surface energy balance and the ice‐associated ecosystem because they transmit more solar radiation compared to bare ice. In the existing literature, melt ponds are considered as bright windows to the ocean, even during freeze‐up in autumn. In the central Arctic during the summer‐autumn transition in 2018, we encountered a situation where more snow accumulated on refrozen melt ponds compared to the adjacent bare ice, leading to a reduction in light transmittance of the ponds even below that of bare ice. Results from a radiative transfer model support this finding. This situation has not been described in the literature before, but has potentially strong implications for example on autumn ecosystem activity, oceanic heat budget, and thermodynamic ice growth. Plain Language Summary: Arctic sea ice is covered with snow during autumn, winter and spring. During summer, melt ponds evolve in response to surface melting. After snow fall starts again in autumn, these ponds can be filled with a lot of snow compared to bare ice because of their recessed surface. Indeed, during an expedition close to the North Pole in summer and autumn 2018, we measured a thick snow cover on ponds. This thick snow cover reduced the light availability underneath the ponds to levels below that underneath adjacent bare ice. This is a surprising finding, because it is different from the established theory of high light availability underneath melt ponds during both summer and autumn and how this is described in most computer models. It has consequences for our understanding of the ice‐associated ecosystem (organisms that live in and under sea ice). It might also impact the mass and energy balance of central Arctic sea ice during summer‐autumn transition when new sea ice starts forming. Key Points: Refrozen melt ponds may collect a thicker snow cover compared to bare sea ice due to their recessed topographySuch snow‐covered melt ponds transmit less light compared to bare ice of similar typeThis scenario has not been documented before and should be accounted for in studies involving light in a refreezing Arctic Ocean [ABSTRACT FROM AUTHOR]

Abstract Background Adolescent pregnancy is a serious reproductive health problem in Tanzania. However, the risk factors for multidimensional attitudes and behaviors of reproductive health toward pregnancy in Tanzanian adolescents remain unexplored. Methods We collected baseline characteristics and information on attitudes and behaviors of reproductive health from 4161 Tanzanian adolescents in all 54 primary and secondary schools in the Korogwe district. We applied mixed effect multiple regression analyses stratified by sex to find the factors related to reproductive health attitudes and behaviors toward pregnancy. Results In female students, regarding the attitudes of reproductive health, higher age, hope for marriage in the future, a talk with a parent about sex or pregnancy, and a higher hope score were significantly associated with a lower score. For the behaviors of reproductive health, higher age, a talk with a parent about sex or pregnancy, time to talk with a parent about daily life, and a higher hope score were significantly associated with a lower score. In male students, regarding the attitudes of reproductive health, a higher hope score was significantly associated with a lower score. For the behaviors of reproductive health, higher age, time to talk with a parent about daily life, and a higher hope score was significantly associated with a lower score. Conclusions The heterogeneous factor-outcomes association between female and male students suggested that sex-specialized interventions may be required to change their risky attitudes or behaviors of reproductive health. Although we cannot conclude as points of intervention, our study suggested that it may be practical to improve parent-adolescents communication about sex or reproductive health and change adolescents’ views of pregnancy or marriage for gaining financial or social status.

• NEDA-3 status at five years was higher in the aHSCT group compared to alemtuzumab (p = 0.012). • Relapse free survival at five years was significantly higher in the aHSCT group. • aHSCT-treated patients showed improved QoL on HAQUAMS scaling for up to 10 years. • aHSCT showed improvements over alemtuzumab in five out of 12 cognitive tests. Autologous hematopoietic stem cell transplantation (aHSCT) exhibits promising results for multiple sclerosis (MS) in the short term. We investigated the long-term outcome differences in disease progression and cognitive impairment after aHSCT and alemtuzumab treatment. 20 patients receiving aHSCT and 21 patients treated with alemtuzumab between 2007 and 2020 were included in this monocentric observational cohort study. The primary objective was to compare the outcome of both groups with regards to achieving No Evidence of Disease Activity (NEDA-3), defined by the absence of relapses, EDSS progression, and MRI activity. Secondary endpoints in the study included the assessment of neurocognitive functioning, quality of life (QoL), Multiple Sclerosis Functional Composite (MSFC), and EDSS improvement. Baseline characteristics between both groups were comparable, except for a longer disease duration in the alemtuzumab group of 11.3 years compared to 5.4 years in aHSCT-treated patients (p = 0.002) and a longer mean follow-up time in the aHSCT cohort of 9.0 (range 2.8–15.7) years compared to 5.9 years (range 0.9–9.2) in alemtuzumab patients. NEDA-3 was more frequently observed in the aHSCT group with 75.0 % and 55.0 % at five and 10 years, respectively, than in the alemtuzumab group with only 40.0 % at five years (p = 0.012). Relapse free survival was higher in the aHSCT group (p < 0.001). None of the aHSCT-treated patients showed new T2-lesions six months after therapy initiation until the end of the observational period in contrast to 35.0 % of the alemtuzumab-treated patients showing new T2-lesions (95 %CI 14.2–98.9, p = 0.002). aHSCT-treated patients showed significantly improved cognitive performance in five out of 12 cognitive tests whereas alemtuzumab treated patients deteriorated in four out of 12 tests. Quality of life remained on a constant level for up to 10 years in patients receiving aHSCT with improved scores for the subscale fatigue (p = 0.013). aHSCT seems to be superior to alemtuzumab in maintaining long-term NEDA-3 status, improving cognition and stabilizing quality of life for up to 10 years. [ABSTRACT FROM AUTHOR]

Besides welding, high temperature vacuum repair-brazing is already established for nickel-based alloy turbine blades in the aerospace and power plant industries. After the worn turbine blade has been decoated to its substrate material, the filler metal is deposited as a paste, (melt-spin) foil or tape which also consists of a nickel-based alloy. Following this, the hot-gas corrosion protective coating (e.g. NiCoCrAlY) is applied using thermal spraying. The brazed turbine blade is ground or milled to size and subsequently aluminized to further increase its corrosion resistance. Using the current state of technology, a turbine blade can undergo approximately 3 to 4 repair cycles. In the present study, the development of a two-stage hybrid technology for repairing turbine blades is considered which incorporates, on the one hand, a process technology and manufacturing aspects and, on the other hand, considers material-technological mechanisms. During the first stage of this hybrid technology, the filler metal together with the hot-gas corrosion protective coating is applied using thermal spraying. The subsequent second stage combines the brazing and aluminizing processes. The technology developed here brings technical and economic advantages whilst enabling the current state-of-the-art's corresponding process chain for repairing turbine blades to be shortened. [ABSTRACT FROM AUTHOR]

In vertebrates, darker individuals are often found to be more active and willing to take risks (representing characteristics of a 'proactive' coping style), whereas lighter individuals are instead more cautious and less active (representing characteristics of a 'reactive' coping style). It is thus generally expected that melanin-based coloration and proactivity form a suite of positively integrated traits at the among-individual level. Here, we use a multigenerational pedigree of free-living great tits ( Parus major) to partition variation in, and the correlation between, melanin-based breast stripe ('tie') size and exploration behaviour (a proxy for coping style) into its among- and within-individual components. We show that both traits harbour heritable variation. Against predictions, tie size and speed of exploration were negatively correlated at the among-individual level due to the combined influences of permanent environmental and additive genetic effects. By contrast, the two traits were weakly positively correlated within individuals (i.e. individuals increasing in tie size after moult tended to become more explorative). The patterns of among-individual covariance were not caused by correlational selection as we found additive and opposite selection pressures acting on the two traits. These findings imply that testing hypotheses regarding the existence of a 'syndrome' at the among-individual level strictly requires variance partitioning to avoid inappropriate interpretations as the negative 'unpartitioned' phenotypic correlation between exploration and tie size resulted from counteracting effects of within- and among-individual correlations. Identifying sources and levels of (co)variation in phenotypic traits is thus critical to our understanding of biological patterns and evolutionary processes. [ABSTRACT FROM AUTHOR]

The ice-covered central Arctic Ocean is characterized by low primary productivity due to light and nutrient limitations. The recent reduction in ice cover has the poten-tial to substantially increase phytoplankton primary production, but little is yet known about the fate of the ice-associated primary production and of the nutrient supply with increasing warming. This study presents results from the central Arctic Ocean collected during summer 2012, when sea-ice extent reached its lowest ever recorded since the onset of satellite observations. Net primary productivity (NPP) was measured in the water column, sea ice and melt ponds by 14CO2 uptake at different irradiances. Photosynthesis vs. irradiance (PI) curves were established in laboratory experiments and used to upscale measured NPP to the deep Eurasian Basin (north of 78° N) using the irradiance-based Central Arctic Ocean Primary Productivity (CAOPP) model. In addition, new annual production has been calculated from the seasonal nutrient drawdown in the mixed layer since last winter. Results show that ice algae can contribute up to 60 % to primary production in the central Arctic Ocean at the end of the productive season (August-September). The ice-covered water column has lower NPP rates than open water due to light limitation in late summer. As indicated by the nutrient ratios in the euphotic zone, nitrate was limiting primary production in the deep Eurasian Basin close to the Laptev Sea area, while silicate was the main limiting nutrient at the ice margin near the Atlantic inflow. Although sea-ice cover was substantially reduced in 2012, total annual new production in the Eurasian Basin was 17 ± 7 Tg C yr-1, which is within the range of estimates of previous years. However, when adding the contribution by sub-ice algae, the annual production for the deep Eurasian Basin (north of 78° N) could double previous estimates for that area with a surplus of 16 Tg C yr-1. Our data suggest that sub-ice algae are an important component of the productivity in the ice-covered Eurasian Basin of the central Arctic Ocean. It remains an important question whether their contribution to productivity is on the rise with thinning ice, or whether it will decline due to overall sea-ice retreat and be replaced by phytoplankton. [ABSTRACT FROM AUTHOR]

The ice-covered Central Arctic Ocean is characterized by low primary productivity due to light and nutrient limitations. The recent reduction in ice cover has the potential to substantially increase phytoplankton primary production, but little is yet known about the fate of the ice-associated primary production and of the nutrient supply with increasing warming. This study presents results from the Central Arctic Ocean collected during summer 2012, when sea-ice reached a minimum extent since the onset of satellite observations. Net primary productivity (NPP) was measured in the water column, sea ice and melt ponds by 14CO2 uptake at different irradiances. Photosynthesis vs. irradiance (PI) curves were established in laboratory experiments and used to upscale measured NPP to the deep Eurasian Basin (north of 78° N) using the irradiance-based Central Arctic Ocean Primary Productivity (CAOPP) model. In addition, new annual production was calculated from the seasonal nutrient drawdown in the mixed layer since last winter. Results show that ice algae can contribute up to 60% to primary production in the Central Arctic at the end of the season. The ice-covered water column has lower NPP rates than open water due to light limitation. As indicated by the nutrient ratios in the euphotic zone, nitrate was limiting primary production in the deep Eurasian Basin close to the Laptev Sea area, while silicate was the main limiting nutrient at the ice margin near the Atlantic inflow. Although sea-ice cover was substantially reduced in 2012, total annual new production in the Eurasian Basin was 17 ± 7TgCyr-1 which is within the range of estimates of previous years. However, when adding the contribution by sub-ice algae, the annual production for the deep Eurasian Basin (north of 78° N) could double previous estimates for that area with a surplus of 16 TgCyr-1. Our data suggest that sub-ice algae are an important component of the ice-covered Central Arctic productivity. It remains an important question if their contribution to productivity is on the rise with thinning ice, or if it will decline due to overall sea-ice retreat and be replaced by phytoplankton. [ABSTRACT FROM AUTHOR]

The amount of solar radiation transmitted through Arctic sea ice is determined by the thickness and physical properties of snow and sea ice. Light transmittance is highly variable in space and time since thickness and physical properties of snow and sea ice are highly heterogeneous on variable time and length scales. We present field measurements of under-ice irradiance along transects under undeformed land-fast sea ice at Barrow, Alaska (March, May, and June 2010). The measurements were performed with a spectral radiometer mounted on a floating under-ice sled. The objective was to quantify the spatial variability of light transmittance through snow and sea ice, and to compare this variability along its seasonal evolution. Along with optical measurements, snow depth, sea ice thickness, and freeboard were recorded, and ice cores were analyzed for chlorophyll a and particulate matter. Our results show that snow cover variability prior to onset of snow melt causes as much relative spatial variability of light transmittance as the contrast of ponded and white ice during summer. Both before and after melt onset, measured transmittances fell in a range from one third to three times the mean value. In addition, we found a twentyfold increase of light transmittance as a result of partial snowmelt, showing the seasonal evolution of transmittance through sea ice far exceeds the spatial variability. However, prior melt onset, light transmittance was time invariant and differences in under-ice irradiance were directly related to the spatial variability of the snow cover. [ABSTRACT FROM AUTHOR]

A comprehensive measurement program was conducted during 16 days of a 3 week long ice pack drift, from 15 August to 1 September 2008 in the central Amundsen Basin, Arctic Ocean. The data, sampled as part of the Arctic Summer Cloud Ocean Study (ASCOS), included upper ocean stratification, mixing and heat transfer as well as transmittance solar radiation through the ice. The observations give insight into the evolution of the upper layers of the Arctic Ocean in the transition period from melting to freezing. The ocean mixed layer was found to be heated from above and, for summer conditions, the net heat flux through the ice accounted for 22% of the observed change in mixed layer heat content. Heat was mixed downward within the mixed layer and a small, downward heat flux across the base of the mixed layer accounted for the accumulated heat in the upper cold halocline during the melting season. On average, the ocean mixed layer was cooled by an ocean heat flux at the ice/ocean interface (1.2 W m-2) and heated by solar radiation through the ice (-2.6 W m-2). An abrupt change in surface conditions halfway into the drift due to freezing and snowfall showed distinct signatures in the data set and allowed for inferences and comparisons to be made for cases of contrasting forcing conditions. Transmittance of solar radiation was reduced by 59 % in the latter period. From hydrographic observations obtained earlier in the melting season, in the same region, we infer a total fresh water equivalent of 3.3 m accumulated in the upper ocean, which together with the observed saltier winter mixed layer indicates a transition towards a more seasonal ice cover in the Arctic. [ABSTRACT FROM AUTHOR]

In many seabird species, the genetic structure of the populations remains poorly known despite potential consequences for conservation. The globally threatened wandering albatross Diomedea exulans displays specific traits, including limited population size, strong philopatry, adults almost always returning to breed on the island where they made their first breeding attempt, delayed maturity, high longevity and low fecundity. Using both genetic and demographic methods, we evaluated how these traits might affect the structure within (inbreeding, low variability) and among (restricted gene flow) discrete wandering albatross colonies. Our study was conducted on Possession Island, Crozet archipelago, and in the Kerguelen archipelago. The genetic approach was based on three colonies and 10 microsatellite loci. The demographic approach used data from a 36-year capture–mark–recapture survey of the entire population from Possession Island. Inbreeding occurred as often as expected under random pairing. Genetic variability in each colony did not exceed 6.3 alleles per locus. However, no genetic bottleneck was detected. No significant genetic differentiation occurred between the two main colonies from Possession Island ( Fst<0.01), consistent with our demographic estimates of dispersal. Conversely, the genetic differentiation between Possession Island and Kerguelen was significant. Although males are more philopatric than females, genetic differentiation among colonies was not higher in males and no significant genetic differentiation between sexes was observed. Finally, we propose that the population from Crozet and that from Kerguelen are considered as distinct management units. [ABSTRACT FROM AUTHOR]