Picoheterotroph (Bacteria and Archaea) biomass distribution in the global ocean

We compiled a database of 39 766 data points consisting of flow cytometric and microscopical measurements of picoheterotroph abundance, including both Bacteria and Archaea. After gridding with 1° spacing, the database covers 1.3% of the ocean surface. There are data covering all ocean basins and depths except the Southern Hemisphere below 350m or from April until June. The average picoheterotroph biomass is 3.9 ± 3.6 µg Cl-1 with a 20-fold decrease between the surface and the deep sea. We estimate a total ocean inventory of about 1.3 × 1029 picoheterotroph cells. Surprisingly, the abundance in the coastal regions is the same as at the same depths in the open ocean. Using an average of published open ocean measurements for the conversion from abundance to carbon biomass of 9.1 fg cell-1, we calculate a picoheterotroph carbon inventory of about 1.2 Pg C. The main source of uncertainty in this inventory is the conversion factor from abundance to biomass. Picoheterotroph biomass is ? 2 times higher in the tropics than in the polar oceans

A continuous isotropic-nematic liquid crystalline transition of F-actin solutions

The phase transition from the isotropic (I) to nematic (N) liquid crystalline suspension of F-actin of average length $3~\mu$m or above was studied by local measurements of optical birefringence and protein concentration. Both parameters were detected to be continuous in the transition region, suggesting that the I-N transition is higher than 1st order. This finding is consistent with a recent theory by Lammert, Rokhsar & Toner (PRL, 1993, 70:1650), predicting that the I-N transition may become continuous due to suppression of disclinations. Indeed, few line defects occur in the aligned phase of F-actin. Individual filaments in solutions of a few mg/ml F-actin undergo fast translational diffusion along the filament axis, whereas both lateral and rotational diffusions are suppressed.Comment: 4 pages with 4 figures. Submitted to Physical Review Letter

Anisotropic Pair Correlations and Structure Factors of Confined Hard-Sphere Fluids: An Experimental and Theoretical Study

We address the fundamental question: how are pair correlations and structure factors of hard-sphere fluids affected by confinement between hard planar walls at close distance? For this purpose, we combine x-ray scattering from colloid-filled nanofluidic channel arrays and first-principles inhomogeneous liquid-state theory within the anisotropic Percus-Yevick approximation. The experimental and theoretical data are in remarkable agreement at the pair-correlation level, providing the first quantitative experimental verification of the theoretically predicted confinement-induced anisotropy of the pair-correlation functions for the fluid. The description of confined fluids at this level provides, in the general case, important insights into the mechanisms of particle-particle interactions in dense fluids under confinement

Gripforce reduction in children with an upper neonatal brachial plexus palsy

Objective: To assess gripforce in children with a C5 and C6 neonatal brachial plexus palsy, as it may affect hand use. Applying classic innervation patterns, gripforce should not be affected, as hand function is not innervated by C5 or C6. This study compares gripforce in children with a neonatal brachial plexus palsy with that in a healthy control group, and assesses correlations with hand sensibility, bimanual use and external rotation.Methods: A total of 50 children with neonatal brachial plexus palsy (mean age 9.8 years) and 25 controls (mean age 9.6 years) were investigated. Nerve surgery had been performed in 30 children, and 20 children had been treated conservatively. Gripforce of both hands was assessed using a Jamar dynamometer. Sensibility of the hands was assessed with 2-point discrimination and Semmes-Weinstein monofilaments. External rotation was assessed using the Mallet score. Bimanual use was measured by using 1 of 3 dexterity items of the Movement Assessment Battery for Children-2. The affected side of the neonatal brachial plexus palsy group was compared with the non-dominant hand of the control group using 1-way analysis of variance (ANOVA), x(2) and Mann-Whitney tests.Results: The mean gripforce of the affected non-dominant hand of children with neonatal brachial plexus palsy was reduced compared with healthy controls (95 N and 123 N, respectively, with p = 0.001). The mean gripforce of the non-dominant hand in the control group was 92% of that of the dominant hand, while it was only 76% in the neonatal brachial plexus palsy group (p =0.04). There was no relationship between gripforce reduction and sensibility, bimanual use or shoulder external rotation.Discussion: The gripforce in neonatal brachial plexus palsy infants with a C5 and C6 lesion is lower than that of healthy controls, although classic interpretation of upper limb innervation excludes this finding. The reduction in gripforce in upper neonatal brachial plexus palsy lesions is not widely appreciated as a factor inherently compromising hand use. The reduction in gripforce should be taken into consideration in planning the type of rehabilitation and future activities.Scientific Assessment and Innovation in Neurosurgical Treatment Strategie

Drivers and uncertainties of future global marine primary production in marine ecosystem models

Past model studies have projected a global decrease in marine net primary production (NPP) over the 21st century, but these studies focused on the multi-model mean rather than on the large inter-model differences. Here, we analyze model-simulated changes in NPP for the 21st century under IPCC's high-emission scenario RCP8.5. We use a suite of nine coupled carbon–climate Earth system models with embedded marine ecosystem models and focus on the spread between the different models and the underlying reasons. Globally, NPP decreases in five out of the nine models over the course of the 21st century, while three show no significant trend and one even simulates an increase. The largest model spread occurs in the low latitudes (between 30° S and 30° N), with individual models simulating relative changes between −25 and +40 %. Of the seven models diagnosing a net decrease in NPP in the low latitudes, only three simulate this to be a consequence of the classical interpretation, i.e., a stronger nutrient limitation due to increased stratification leading to reduced phytoplankton growth. In the other four, warming-induced increases in phytoplankton growth outbalance the stronger nutrient limitation. However, temperature-driven increases in grazing and other loss processes cause a net decrease in phytoplankton biomass and reduce NPP despite higher growth rates. One model projects a strong increase in NPP in the low latitudes, caused by an intensification of the microbial loop, while NPP in the remaining model changes by less than 0.5 %. While models consistently project increases NPP in the Southern Ocean, the regional inter-model range is also very substantial. In most models, this increase in NPP is driven by temperature, but it is also modulated by changes in light, macronutrients and iron as well as grazing. Overall, current projections of future changes in global marine NPP are subject to large uncertainties and necessitate a dedicated and sustained effort to improve the models and the concepts and data that guide their developmen

Reading, Trauma and Literary Caregiving 1914-1918: Helen Mary Gaskell and the War Library

This article is about the relationship between reading, trauma and responsive literary caregiving in Britain during the First World War. Its analysis of two little-known documents describing the history of the War Library, begun by Helen Mary Gaskell in 1914, exposes a gap in the scholarship of war-time reading; generates a new narrative of "how," "when," and "why" books went to war; and foregrounds gender in its analysis of the historiography. The Library of Congress's T. W. Koch discovered Gaskell's ground-breaking work in 1917 and reported its successes to the American Library Association. The British Times also covered Gaskell's library, yet researchers working on reading during the war have routinely neglected her distinct model and method, skewing the research base on war-time reading and its association with trauma and caregiving. In the article's second half, a literary case study of a popular war novel demonstrates the extent of the "bitter cry for books." The success of Gaskell's intervention is examined alongside H. G. Wells's representation of textual healing. Reading is shown to offer sick, traumatized and recovering combatants emotional and psychological caregiving in ways that she could not always have predicted and that are not visible in the literary/historical record

Corrigendum: Short-lived positron emitters in beam-on PET imaging during proton therapy (2015 Phys. Med. Biol. 60 8923)

Because of strong indications of multiple counting by the multi-channel scaler (MCS) during most of the experiments described in Dendooven et al (2015 Phys. Med. Biol. 60 8923–47), the production of short-lived positron emitters in the stopping of 55 MeV protons in water, carbon, phosphorus and calcium was remeasured. The new results are reported here. With proper single counting of the MCS, the new production rates are 1.1 to 2.9 times smaller than reported in Dendooven et al (2015 Phys. Med. Biol. 60 8923–47). The omission of the conversion from MCS time bin to time unit in the previous data analysis was corrected, leading to an increase of the production rate by a factor of 2.5 or 10 for some nuclides. The most copiously produced short-lived nuclides and their production rates relative to the relevant long-lived nuclides are: 12N (T 1/2  =  11 ms) on carbon (5.3% of 11C), 29P (T 1/2  =  4.1 s) on phosphorus (23% of 30P) and 38mK (T 1/2  =  0.92 s) on calcium (173% of 38gK). The number of decays integrated from the start of an irradiation as a function of time during the irradiation of PMMA and 4 tissue materials has been determined. For (carbon-rich) adipose tissue, 12N dominates up to 70 s. On bone tissue, 38mK dominates the beam-on PET counts from 0.2–0.7 s until about 80–110 s. Considering nuclides created on phosphorus and calcium, the short-lived ones provide 8 times more decays than the long-lived ones during a 70 s irradiation. Bone tissue will thus be much better visible in beam-on PET compared to PET imaging after an irradiation. From the estimated number of 12N PET counts, we conclude that, for any tissue, except carbon-poor ones, 12N PET imaging potentially provides equal quality proton range information as prompt gamma imaging with an optimized knife-edge slit camera

What range of motion is achieved 5 years after external rotationplasty of the shoulder in infants with an obstetric brachial plexus injury?

Background Obstetric brachial plexus injuries result from traction injuries during delivery, and 30% of these children have persisting functional limitations related to an external rotation deficit of the shoulder. Little is known about the long-term effect of soft-tissue procedures of the shoulder in patients with obstetric brachial plexus injuries. Questions/purposes (1) After soft-tissue release for patients with passive external rotation less than 20 degrees and age younger than 2 years and for patients older than 2 years with good external rotation strength, what are the improvements in passive external rotation and abduction arcs at 1 and 5 years? (2) For patients who underwent staged tendon transfer after soft-tissue release, what are the improvements in active external rotation and abduction arcs at 1 and 5 years? (3) For patients with passive external rotation less than 20 degrees and no active external rotation, what are the improvements in active external rotation and abduction arcs at 1 and 5 years? Methods This was a retrospective analysis of a longitudinally maintained institutional database. Between 1996 and 2009, 149 children underwent a soft-tissue procedure of the shoulder for an internal rotation contracture. The inclusion criteria were treatment with an internal contracture release and/or tendon transfer, a maximum age of 18 years at the time of surgery, and a minimum follow-up period of 2 years. Six patients were older than 18 years at the time of surgery and 31 children were seen at our clinic until 1 year postoperatively, but because they had good clinical results and lived far away from our center, these children were discharged to physical therapists in their hometown for annual follow-up. Thus, 112 children (59 boys) were available for analysis. Patients with passive external rotation less than 20 degrees and age younger than 2 years and patients older than 2 years with good external rotation strength received soft-tissue release only (n = 37). Of these patients, 17 children did not have adequate active external rotation, and second-stage tendon transfer surgery was performed. For patients with passive external rotation less than 20 degrees with no active external rotation, single-stage contracture release with tendon transfer was performed (n = 68). When no contracture was present (greater than 20 degrees of external rotation) but the patient had an active deficit (n = 7), tendon transfer alone was performed; this group was not analyzed. A functional assessment of the shoulder was performed preoperatively and postoperatively at 6 weeks, 3 months, and annually thereafter and included abduction, external rotation in adduction and abduction, and the Mallet scale. Results Internal contracture release resulted in an improvement in passive external rotation in adduction and abduction of 29 degrees (95% confidence interval, 21 to 38; p < 0.001) and 17 degrees (95% CI, 10 to 24; p < 0.001) at 1 year of follow-up and 25 degrees (95% CI, 15-35; p < 0.001) and 15 degrees (95% CI, 7 to 24; p = 0.001) at 5 years. Because of insufficient strength of the external rotators after release, 46% of the children (17 of 37) underwent an additional tendon transfer for active external rotation, resulting in an improvement in active external rotation in adduction and abduction at each successive follow-up visit. Patients with staged transfers had improved active function; improvements in active external rotation in adduction and abduction were 49 degrees (95% CI, 28 to 69; p < 0.05) and 45 degrees (95% CI, 11 to 79; p < 0.001) at 1 year of follow-up and 38 degrees (95% CI, 19 to 58; p < 0.05) and 23 degrees (95% CI, -8 to 55; p < 0.001) at 5 years. In patients starting with less than 20 degrees of passive external rotation and no active external rotation, after single-stage contracture release and tendon transfer, active ROM was improved. Active external rotation in adduction and abduction were 75 degrees (95% CI, 66 to 84; p < 0.001) and 50 degrees (95% CI, 43 to 57; p < 0.001) at 1 year of follow-up and 65 degrees (95% CI, 50 to 79; p < 0.001) and 40 degrees (95% CI, 28 to 52; p < 0.001) at 5 years. Conclusion Young children with obstetric brachial plexus injuries who have internal rotation contractures may benefit from soft-tissue release. When active external rotation is lacking, soft-tissue release combined with tendon transfer improved active external rotation in this small series. Future studies on the degree of glenohumeral deformities and functional outcome might give more insight into the level of increase in external rotation.Development and application of statistical models for medical scientific researc