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The composition of communities of fruit‐feeding butterflies in the Brazilian Atlantic forest changes in response to landscape fragmentation and can be used as an indicator of habitat quality. Landscape fragmentation, aridity, and early signs of global warming at the northernmost distribution of this biome may impose extra challenges for species persistence.We aim to clarify the drivers of fruit‐feeding butterflies' metacommunity structure in the northernmost portion of the Brazilian Atlantic Forest. We propose to disentangle consequences of habitat loss from fragmentation per se by using both habitat amount and patch scale metrics.We sampled fruit‐feeding butterflies in 15 forest fragments of up to ~30 ha during 1 year. We used fragment size, shape, distance to nearest perennial stream, Euclidean distance to nearest neighbour, forest habitat amount, proximity index, and the percentage of sugarcane within a buffer to elucidate patterns of species richness, abundance, and beta diversity.A configuration metric, stream distance, was the only variable predicting metacommunity total abundance and richness: fragments farther from water had fewer species and individuals. However, forest habitat amount and sugar cane were important to rarefied richness and species replacement between fragments.Our findings suggest that streams and associated riparian zones provide source populations for the butterfly metacommunities in this landscape, which fits the mass effect model. We also emphasise that small forest patches have high conservation value for persistence of butterfly populations, because each fragment preserves a substantial portion of the total species pool. [ABSTRACT FROM AUTHOR]

The impact of midline shift (MLS) on long-term survival and progression in glioblastoma (GBM) is unknown. The objective of this study was to analyze the influence of mass effect on survival and progression with consideration of the patient demographics, tumor morphology, operative techniques, molecular pathology, and postoperative treatment. One hundred ninety-eight patients with GBM were analyzed retrospectively. Both MLS groups (< or ≥ 10 mm) were compared with regard to survival, progression-free survival (PFS), and postoperative course of Karnofsky Performance Status (KPS). A two-sided Fisher exact test showed no statistically significant differences in the confounders between the low- and high-MLS groups. The median survival was 18.0 months (95% confidence interval (CI) = 15.3–20.7) in the low-MLS group (n = 173) and 9.0 months (95% CI = 4.8–13.2) in the high-MLS group (n = 25) (p = 0.045). In the high-MLS group, 59.1% (13/22) with an initially high MLS had a KPS of less than 70% after 3 months, whereas 20.5% of the low-MLS group had a KPS of less than 70% (p < 0.001). Binary logistic regression analysis including the O-6-methylguanine-DNA methyltransferase (MGMT) status, extent of resection, baseline KPS, and MIB-I index showed low MLS as the only predictor for survival at 12 months (p = 0.046, odds ratio (OR) = 2.70, 95% CI = 1.0–7.2). Median PFS was 6.0 months in the high-MLS group and 9.0 months in the low-MLS group (log-rank test; p = 0.08). An initial midline shift of 10 mm or greater seems to be an imaging characteristic that independently predicts the survival in glioblastoma. [ABSTRACT FROM AUTHOR]

Elevation is involved in determining plant diversity in montane ecosystems. This study examined whether the distribution of plants in the Yatsugatake Mountains, central Japan, substantiated hypotheses associated with an elevational diversity gradient. Species richness of trees, shrubs, herbs, ferns, and bryophytes was investigated in study plots established at 200‐m elevational intervals from 1,800 to 2,800 m. The changes in plant diversity (alpha and beta diversities, plant functional types, and elevational ranges) with elevation were analyzed in relation to climatic factors and elevational diversity gradient hypotheses, that is, mass effect, mid‐domain effect, and Rapoport's elevational rule. In addition, the elevational patterns of dominance of plant functional types were also analyzed. A comparison of alpha and beta diversities revealed that different plant groups responded variably to elevation; the alpha diversity of trees and ferns decreased, that of herbs increased, whereas the alpha diversity of shrubs and bryophytes showed a U‐shaped relationship and a hump‐shaped pattern. The beta diversity of shrubs, herbs, and bryophytes increased above the subalpine–alpine ecotone. In accordance with these changes, the dominance of evergreen shrubs and graminoids increased above this ecotone, whereas that of evergreen trees and liverworts decreased. None of the plant groups showed a wide elevational range at higher elevations. These elevational patterns of plant groups were explained by climatic factors, and not by elevational diversity gradient hypotheses. Of note, the changes in the dominance of plant groups with elevation can be attributed to plant–plant interactions via competition for light and the changes in physical habitat. These interactions could alter the elevational diversity gradient shaped by climatic factors. [ABSTRACT FROM AUTHOR]

The paper offers a reading of Mass Effect: Andromeda (BioWare, 2017) vis-à-vis lost world romance (also dubbed "lost race romance", or "imperial romance"), a late-Victorian era novelistic genre originating from H. Rider Haggard's King Solomon's Mines and serving as a major tool for British Empire propaganda and a source of early science-fiction conventions. We claim that the narrative failure of this ill-received game stems from its adherence to the rigid principles and forceful themes of the genre and the colonial and imperial imaginary informing it. Our analysis aims at highlighting the way 19th-century novelistic convention can be remediated as contemporary digital games, and to expose the link between the imperial imaginary and the ways in which open-world digital games are structured, on both the narrative and gameplay levels, even when they do not directly refer to the historical colonial legacy. [ABSTRACT FROM AUTHOR]

Demyelinating lesions which present as solitary contrast-enhancing masses pose a diagnostic challenge for both radiologists and surgical neuropathologists and can mimic a number of intracranial space occupying lesions either neoplastic/inflammatory. Herein, a series of seven cases with particular emphasis on histopathological and immunohistochemical characterisation of these lesions was presented. The seven cases of Tumefactive Demyelinating Lesions (TDLs) diagnosed on histopathology include three males and four females with age ranging from 10 to 58 years (median-25 years) chiefly presenting with focal neurological deficits. Radiologically, the lesions were predominantly localised in the temporo-parietal region. Histologically, the lesions were well-demarcated, hypercellular with infiltration by foamy macrophages and reactive astrocytes. In addition, Creutzfeldt astrocytes and granular mitoses were seen. Additional special stains for myelin (Luxol fast blue), demonstrated focal, sharply marginated loss of myelin, and Immunohistochemistry (IHC) with Neurofilament (NF) for axons showed relative preservation of axons in areas of myelin loss. IHC with Glial Fibrillary Acidic Protein (GFAP) highlighted the fibrillary processes of the reactive astrocytes and the cytoplasm of the Creutzfeldt cells. Knowledge of the characteristic features such as welldemarcated lesions with histological characterisation by large number of macrophages, including Creutzfeldt astrocytes, granular mitoses and perivascular inflammation should raise index of suspicion and prompt pathologist to do additional myelin stains and IHC to confirm demyelination and preservation of intact axons thereby, differentiating from neoplasms and other non-neoplastic inflammatory lesions.

Demyelinating lesions which present as solitary contrast-enhancing masses pose a diagnostic challenge for both radiologists and surgical neuropathologists and can mimic a number of intracranial space occupying lesions either neoplastic/inflammatory. Herein, a series of seven cases with particular emphasis on histopathological and immunohistochemical characterisation of these lesions was presented. The seven cases of Tumefactive Demyelinating Lesions (TDLs) diagnosed on histopathology include three males and four females with age ranging from 10 to 58 years (median-25 years) chiefly presenting with focal neurological deficits. Radiologically, the lesions were predominantly localised in the temporo-parietal region. Histologically, the lesions were well-demarcated, hypercellular with infiltration by foamy macrophages and reactive astrocytes. In addition, Creutzfeldt astrocytes and granular mitoses were seen. Additional special stains for myelin (Luxol fast blue), demonstrated focal, sharply marginated loss of myelin, and Immunohistochemistry (IHC) with Neurofilament (NF) for axons showed relative preservation of axons in areas of myelin loss. IHC with Glial Fibrillary Acidic Protein (GFAP) highlighted the fibrillary processes of the reactive astrocytes and the cytoplasm of the Creutzfeldt cells. Knowledge of the characteristic features such as welldemarcated lesions with histological characterisation by large number of macrophages, including Creutzfeldt astrocytes, granular mitoses and perivascular inflammation should raise index of suspicion and prompt pathologist to do additional myelin stains and IHC to confirm demyelination and preservation of intact axons thereby, differentiating from neoplasms and other non-neoplastic inflammatory lesions. [ABSTRACT FROM AUTHOR]

• "Giant" gallbladder development in the context of acute on chronic cholecystitis is extremely rare and may present with atypical symptoms secondary to mass effect. • Current grading systems for acute cholecystitis severity do not include assessment based on size making them insufficient in predicting "giant" gallbladder surgical prognosis. • Laparoscopic cholecystectomy was performed successfully despite the large gallbladder size without intraoperative/postoperative complications. Gallbladder disease is a common surgical pathology. Gallstones can remain asymptomatic or develop into an acute cholecystitis and need for surgical intervention. Significant enlargement of the gallbladder well beyond the normal volume is rare. Such "giant" gallbladders can affect feasibility of subsequent management options. An 80-year-old female presented to the emergency department with a two-day history of acute on chronic gastric reflux with nausea and vomiting. On examination, she had right upper quadrant abdominal pain. CT imaging identified an enormous gallbladder creating mass effect and compression on the distal stomach. She underwent successful laparoscopic cholecystectomy and was discharged from the hospital the next day, doing well. On two-week follow up, her reflux symptoms had completely resolved and she had no complaints. Giant gallbladders are a rare entity. Our patient's case is unique in both its occurrence as well as presentation with predominant reflux symptoms secondary to mass effect by the enlarged gallbladder. Current cholecystitis grading systems do not utilize size as a means of predicting severity and risk of operative complications or difficulty of procedure. Laparoscopic cholecystectomy was a successful approach in managing this extreme pathology. Updated classifications systems that include size and mass effect as a predictive measure are needed to better assess surgical outcomes, especially in "giant" gallbladder disease. Despite the large size and potential mass effect on surrounding structures, laparoscopic cholecystectomy can still be attempted if no other contraindications exist. [ABSTRACT FROM AUTHOR]

Understanding how species richness changes along altitudinal gradients and what mechanisms answer for those patterns has intrigued increasing attention from numerous researchers, however, there is still no consistent agreement on these questions. Here, based on available distribution records, we explored the elevational pattern of species richness for seed plants in the Mt. Namjagbarwa region (Eastern Himalayas, China), a previously unexplored region. Species richness in each 100 m elevation band was estimated by spatial interpolation method according to their recorded elevation range over a large altitudinal gradient from 700 to 5000 m. In each elevation band, species richness was related to several explanatory factors, including temperature, humidity, spatially related variables and biogeographical distributions. Regression analyses were performed to obtain a quantitative assessment of the relative contribution of each predictor to the empirical richness pattern. Overall, species richness along elevation showed a hump-shaped pattern, with a peak at 1600–2000 m. In all sub-groups (life form, biogeographical affinity, and range-size category), species richness showed unimodal patterns with increasing elevation generally, but with different peak positions. Regression models indicated species richness patterns are highly correlated with energy-related factor in most data sets, explaining the observed richness patterns, but also more or less associated with other variables (climatic variation, area, precipitation, and mid-domain effect). The water-energy dynamics model was found to explain the elevational species richness patterns. Meantime, there was an elevational coincidence between maximum species richness and floristic overlap index, which proving the role of the biotic process in shaping the species richness gradient. Our findings reconfirmed that the elevational richness gradient is influenced by many processes, including ecological factors and evolutionary history, and suggested the need to consider more factors in order to determine key mechanisms in future studies.

Background: Mass effect associated with large or giant aneurysms is an intractable problem for traditional endovascular treatments. Preventing recurrence of aneurysms requires dense coiling, which may aggravate the mass effect. However, the flow diverter (FD) is a new device that avoids the need for dense coiling. This study was performed to investigate whether use of FDs with adjunctive coil embolization can relieve the aneurysmal mass effect and to explore the factors that affect the variation of compressional symptoms.Methods: We retrospectively evaluated patients with compressional symptoms caused by unruptured aneurysms who underwent endovascular treatment with an FD with adjunctive coil embolization at our center from January 2015 to December 2017. Imaging follow-up included digital subtraction angiography (DSA) ranging from 11 to 14 months and magnetic resonance imaging (MRI) ranging from 24 to 30 months; the former was used to evaluate the intracavitary volume, and the latter was used to measure the variation of the mass effect. Follow-up physical examinations were performed to observe variations of symptoms.Results: In total, 22 patients with 22 aneurysms were treated by an FD combined with coil embolization. All 22 patients underwent the last clinical follow-up. Regarding compressional symptoms, 12 (54.54%) patients showed improvement, 6 (27.27%) were fully recovered, and 6 (27.27%) showed improvement but with incomplete cranial palsy. However, five (22.72%) patients showed no change, four (18.18%) showed worsening symptoms compared with their preoperative state, and one (4.55%) died of delayed rupture. Seventeen of the 22 patients underwent MRI. Of these 17 patients, the aneurysm shrank in 13 (76.47%) and no significant change occurred in 4 (23.53%). In the multivariate analysis, a short duration from symptom occurrence to treatment (p = 0.03) and younger patient age (p = 0.038) were statistically significant factors benefiting symptom improvement, and shrinkage of the aneurysm was associated with favorable clinical outcomes (p = 0.006).Conclusions: Use of the FD with adjunctive loose coil embolization might help to alleviate the compressional symptoms caused by intracranial aneurysms. Shrinkage of the aneurysm, a short duration of symptoms, and younger patient age might contribute to favorable outcomes of mass effect-related symptoms.

Background: Brain metastasis (BM) from colorectal cancer (CRC) is rare with the incidence ranging from 0.6% to 3.2%. There is also an increased incidence of BM with rectal primaries and is consistent with this patient’s presentation. Overall, there is scarce literature on the symptoms of patients who present with CRC BMs. Objectives: We present a case of brain metastasis in colorectal cancer presenting with hypertensive urgency and severe headache. Methods and results: This case highlights that neurological deficits are not necessary for BMs in patients with CRC and summarizes and reviews the associated literature regarding BM in CRC. A 57-year-old female with a past medical history of recently diagnosed stage IV moderately differentiated distal rectal adenocarcinoma with liver and lung metastasis was admitted with the primary complaint of hypertensive urgency, severe headache, intractable nausea and vomiting, and diarrhea. Magnetic resonance imaging brain showed a left cerebellar lesion measuring 3.6 × 3.2 × 2.9 cm, ipsilateral transtentorial herniation, and obliteration of the fourth ventricle. The patient was started on steroids and transferred for an urgent neurosurgical intervention to a tertiary care center. Conclusions: Even though BMs are rare in CRC, clinicians should have a high index of suspicion with complaints like hypertensive urgency, headache, nausea, vomiting, vertigo, and blurring of vision triggering imaging studies to rule out BM. The approach to BM has become increasingly individualized as surgical and radiosurgical therapies have continued to evolve Abbreviations: CRC: Colorectal cancer; BM: Brain metastasis; FOLFOX: Folinic acid, fluorouracil and oxaliplatin; CT: Computed tomography; IV: Intravenous; PO: By mouth; BAER: Brain auditory evoked response hearing testing; SSEP’s: Somatosensory evoked potentials; BMFI: Brain metastasis free interval; WBRT: Whole-brain radiation therapy; SRS: Stereotactic radiosurgery.

No abstract available. Article truncated after 150 words. A 20-year-old man presented with a continuous, mild, dull aching pain affecting the left chest pain for 15 days duration. There were no aggravating or relieving factors nor any history of fever, respiratory or cardiac symptoms. The patient’s vital signs were normal and examination of the respiratory and the cardiovascular systems revealed no abnormality. Electrocardiography and biochemical investigations, including cardiac enzymes, were normal. Chest radiography (Figure 1) revealed a subtle opacity causing fullness of the aorto-pulmonary window with subtle, smooth prominence of the left upper cardiac border; the left hilum was visualised discretely through the opacity (Figure 2). The patient underwent enhanced contrast chest CT (CECT, Figure 3) for further evaluation, revealing a large mass measuring 13 x 7.9 x 5 cm in the anterior mediastinum, extending from thoracic inlet to the left cardiophrenic angle. The mass consisted predominantly of fat density, with an average attenuation of - 84 Hounsfield …

Mass effect, allowing species to persist in unfavourable habitats, and dispersal limitation, preventing species from reaching favourable habitats, are the two major dispersal processes. While dispersal limitation can be detected by experimental or modelling techniques, mass effect is more challenging to evaluate, which hampers our ability to disentangle the influence of the environment versus dispersal on species distribution. This is undesirable for biomonitoring programs built on known species–environment relationships.We developed an approach for detection of species influenced by mass effect. We tested it on stream diatoms, a widely used taxonomic group for stream biomonitoring, from four French watersheds. This approach combined (a) an appropriate spatial framework, the asymmetric eigenvector map (AEM), used in species distribution modelling to measure the relative influence of dispersal versus niche processes, (b) an analysis of negative co‐occurrence patterns to separate mass effect from dispersal limitation and (c) a measurement of niche breadths to distinguish between non‐spatially structured generalists and species influenced by mass effect.We propose that species characterized by low negative co‐occurrence values, a high correlation to spatial factors and average to low niche breadths are sensitive to mass effect.Synthesis and applications. We suggest that the sensitivity of species towards mass effect should represent a new ecological trait to be considered for fundamental and applied issues concerning ecology and water quality assessment. Almost all of the species identified here as influenced by mass effect are contributing to the calculation of different diatom‐based indices (e.g. Biological Diatom Index or Specific Pollution‐sensitivity Index) and should be treated with caution when assigning ecological status classes to water bodies. [ABSTRACT FROM AUTHOR]

• The processes that structure rodent metacommunities change across the region. • Environmental processes determine the species composition in each local community. • Environmental processes determine relative abundance of each species in each local community. • Spatial processes vary among ecoregions. • Species-specific dispersal characteristics act differentially in each ecoregion. We studied the role of spatial (regional) and environmental (local) processes in the structuring of rodent metacommunities in three contiguous ecoregions that share the same species pool. The two northern ecoregions are mainly affected by anthropogenic processes (agriculture and urbanization) while the southern one is mainly affected by natural processes (flood and drought pulses). Local communities were described based on the analysis of 77 samples of barn owl pellets. To identify which processes (patch dynamics, species sorting, mass effect or neutral theory) structure each metacommunity we evaluated the percentage of variance explained by space (spatial arrangement of communities) and environment (topography, climate and land cover) in three Variation Partitioning Redundancy Analyses. The percentage of variance in rodent metacommunities composition explained by space and environment was between 38 and 61%, and was significant in all three analyses. The pure space fraction was significant for two of the three ecoregions, while the pure environmental fraction was significant for all three ecoregions. The processes that structure rodent metacommunities change across the region. In all three ecoregions the species sorting played a key role, while, mass effect was a structuring factor for northern metacommunities. These results can be explained by species-specific dispersal characteristics and environmental filtering. [ABSTRACT FROM AUTHOR]

Biotic and abiotic interactions are important factors that explain community assembly. For example, epiphytic communities are shaped by tree traits that can act as environmental filters, but also by positive and/or negative interactions among coexisting epiphytes on a tree.Here, we studied interactions among three widespread atmospheric bromeliads with overlapping niches (Tillandsia recurvata, T. tricholepis and T. pohliana), using experimental data about facilitation through seed capture, interspecific interaction during seed germination and competition among adult individuals. We aim to understand how species interactions are reflected in the natural coexisting patterns of epiphytes in communities at high and low tree densities.Tillandsia pohliana showed higher facilitation by capturing almost all wind‐dispersing seeds, and had the largest reduction in seed germination in the presence of any adult individual, also presenting a relatively high rate of adult mortality in the presence of other individuals. Our results indicate higher colonisation ability for T. pohliana and distinct strategies of rapid exploitation of T. recurvata and T. tricholepis individuals.In natural communities, the coexistence among atmospheric bromeliads may be hampered by dispersal limitations in wind‐dispersed epiphytes at high tree density conditions, but a negative effect of T. recurvata on T. pohliana is still reflected in their reduced coexistence. However, competitive patterns observed in the experimental data may be overshadowed by a possible mass effect driving large communities under such conditions. Our results show the joint effect of positive interactions and high dispersal levels on the community patterns of atmospheric bromeliads. [ABSTRACT FROM AUTHOR]

Different metacommunity perspectives have been developed to describe the relationship between environmental and spatial factors and their relative roles for local communities. However, only little is known about temporal variation in metacommunities and their underlying drivers. We examined temporal variation in the relative roles of environmental and spatial factors for diatom community composition among brackish-watered rock pools on the Baltic Sea coast over a 3-month period. We used a combination of direct ordination, variation partition, and Mantel tests to investigate the metacommunity patterns. The studied communities housed a mixture of freshwater, brackish, and marine species, with a decreasing share of salinity tolerant species along both temporal and spatial gradients. The community composition was explained by both environmental and spatial variables (especially conductivity and distance from the sea) in each month; the joint effect of these factors was consistently larger than the pure effects of either variable group. Community similarity was related to both environmental and spatial distance between the pools even when the other variable group was controlled for. The relative influence of environmental factors increased with time, accounting for the largest share of the variation in species composition and distance decay of similarity in July. Metacommunity organization in the studied rock pools was probably largely explained by a combination of species sorting and mass effect given the small spatial study scale. The found strong distance decay of community similarity indicates spatially highly heterogeneous diatom communities mainly driven by temporally varying conductivity gradient at the marine-freshwater transition zone. [ABSTRACT FROM AUTHOR]

Background: Mass effect associated with large or giant aneurysms is an intractable problem for traditional endovascular treatments. Preventing recurrence of aneurysms requires dense coiling, which may aggravate the mass effect. However, the flow diverter (FD) is a new device that avoids the need for dense coiling. This study was performed to investigate whether use of FDs with adjunctive coil embolization can relieve the aneurysmal mass effect and to explore the factors that affect the variation of compressional symptoms. Methods: We retrospectively evaluated patients with compressional symptoms caused by unruptured aneurysms who underwent endovascular treatment with an FD with adjunctive coil embolization at our center from January 2015 to December 2017. Imaging follow-up included digital subtraction angiography (DSA) ranging from 11 to 14 months and magnetic resonance imaging (MRI) ranging from 24 to 30 months; the former was used to evaluate the intracavitary volume, and the latter was used to measure the variation of the mass effect. Follow-up physical examinations were performed to observe variations of symptoms. Results: In total, 22 patients with 22 aneurysms were treated by an FD combined with coil embolization. All 22 patients underwent the last clinical follow-up. Regarding compressional symptoms, 12 (54.54%) patients showed improvement, 6 (27.27%) were fully recovered, and 6 (27.27%) showed improvement but with incomplete cranial palsy. However, five (22.72%) patients showed no change, four (18.18%) showed worsening symptoms compared with their preoperative state, and one (4.55%) died of delayed rupture. Seventeen of the 22 patients underwent MRI. Of these 17 patients, the aneurysm shrank in 13 (76.47%) and no significant change occurred in 4 (23.53%). In the multivariate analysis, a short duration from symptom occurrence to treatment (p = 0.03) and younger patient age (p = 0.038) were statistically significant factors benefiting symptom improvement, and shrinkage of the aneurysm was associated with favorable clinical outcomes (p = 0.006). Conclusions: Use of the FD with adjunctive loose coil embolization might help to alleviate the compressional symptoms caused by intracranial aneurysms. Shrinkage of the aneurysm, a short duration of symptoms, and younger patient age might contribute to favorable outcomes of mass effect-related symptoms. [ABSTRACT FROM AUTHOR]

Objective: With today's modern imaging modalities, patients diagnosed with renal cell carcinoma (RCC) rarely present symptomatically. In some cases, however, they can develop paraneoplastic syndromes with associated symptoms. To date, only three cases of RCC presenting with chronic dry cough have been reported. We describe six patients who presented with cough that improved following radical nephrectomy. Methods: A retrospective review of patients undergoing partial or radical nephrectomy for renal masses between January 2015 and March 2016 was performed, and patients presenting with a cough were examined. Results: Six patients presented with chronic cough and were discovered to have a large renal mass. Postoperative spontaneous resolution of cough was noted in all but one patient, in whom coughing was reduced and limited to the mornings. Cough duration ranged from 3 months to just over a year. All patients were treated with radical nephrectomy, which was cytoreductive in four patients. Average tumor size was 10.9 cm (SD = 2.2 cm). Five of the tumors had clear cell pathology, and every tumor was Fuhrman grade IV, unifocal, and demonstrated necrosis. Sarcomatoid features were reported in four of the tumors. Conclusion: Our study presents the largest series of patients with RCC who presented with a chronic cough that was significantly improved following radical nephrectomy. We believe the cause of cough is multifactorial and further investigation is needed to clearly elucidate the etiology.

A new dynamic model for vibration analyses of rotating flexible beams with partially covered enhanced active constrained layer damping (EACLD) treatment is developed. To improve the previous EACLD beam modeling method that only considers the edge element stiffness, the edge element of the EACLD patch is modeled as an equivalent spring with attached point mass so that the mass effect of the two added edge elements are included. The discrete rigid-flexible coupled dynamic equations of the hub-beam systems with EACLD treatment in the open-loop and closed-loop cases are derived by using the assumed mode method and Lagrange's equations. The effect of the angular velocity, edge element stiffness, edge element mass, and coverage ratio of the EACLD on the vibration characteristics of the system are investigated. Simulation results show that the edge element stiffness will increase the natural frequencies of the system and make the system become stiffer, while the edge element mass will decrease the natural frequencies of the system. Results from the traditional ACLD beam model, the EACLD beam model without edge element mass and the present EACLD beam model with edge element mass are also compared with each other. It is indicated that the mass effect of the added edge elements should be considered in practical applications and it could even play a positive role in stiffness or damping regulation of systems in conjunction with the vibration controller design. Image 1 • A new dynamic model for beams with partially covered EACLD treatment is developed. • The mass effect of the two added edge elements are included for the first time. • The edge element mass will decrease the natural frequencies of the system. • Influences of parameters on the open-and closed-loop systems are discussed. [ABSTRACT FROM AUTHOR]

In this article, we present a multispecies reaction–advection–diffusion partial differential equation coupled with linear elasticity for modeling tumor growth. The model aims to capture the phenomenological features of glioblastoma multiforme observed in magnetic resonance imaging (MRI) scans. These include enhancing and necrotic tumor structures, brain edema and the so-called "mass effect", a term-of-art that refers to the deformation of brain tissue due to the presence of the tumor. The multispecies model accounts for proliferating, invasive and necrotic tumor cells as well as a simple model for nutrition consumption and tumor-induced brain edema. The coupling of the model with linear elasticity equations with variable coefficients allows us to capture the mechanical deformations due to the tumor growth on surrounding tissues. We present the overall formulation along with a novel operator-splitting scheme with components that include linearly-implicit preconditioned elliptic solvers, and a semi-Lagrangian method for advection. We also present results showing simulated MRI images which highlight the capability of our method to capture the overall structure of glioblastomas in MRIs. [ABSTRACT FROM AUTHOR]

Radiolabeling of nanobodies with radiometals by chelation has the advantage of being simple, fast and easy to implement in clinical routine. In this study, we validated 68Ga/111In-labeled anti-VCAM-1 nanobodies as potential radiometal-based tracers for molecular imaging of atherosclerosis. Both showed specific targeting of atherosclerotic lesions in ApoE−/− mice. Nevertheless, uptake in lesions and constitutively VCAM-1 expressing organs was lower than previously reported for the 99mTc-labeled analog. We further investigated the impact of different radiolabeling strategies on the in vivo biodistribution of nanobody-based tracers. Comparison of the pharmacokinetics between 68Ga-, 18F-, 111In- and 99mTc-labeled anti-VCAM-1 nanobodies showed highest specific uptake for 99mTc-nanobody at all time-points, followed by the 68Ga-, 111In- and 18F-labeled tracer. No correlation was found with the estimated number of radioisotopes per nanobody, and mimicking specific activity of other radiolabeling methods did not result in an analogous biodistribution. We also demonstrated specificity of the tracer using mice with a VCAM-1 knocked-down phenotype, while showing for the first time the in vivo visualization of a protein knock-down using intrabodies. Conclusively, the chosen radiochemistry does have an important impact on the biodistribution of nanobodies, in particular on the specific targeting, but differences are not purely due to the tracer's specific activity. [ABSTRACT FROM AUTHOR]

Highlights • There is an indirect effect of plant diversity on litter decomposition. • Taxonomic, functional components and environmental factors affect litter decomposition. • The effects of diversity on the decomposition process vary with time. Abstract One of the challenges in predicting the effects of biodiversity on ecosystem functioning is understanding the balance between the importance of various diversity components and variations in the environment. In mega-diverse tropical forests, these relationships between plant diversity and ecosystem processes, such as litter decomposition, are poorly explored. While the direct effects of plant diversity on litter decomposition are relatively well known, the indirect effects of diversity, and the local community and microenvironment have rarely been investigated. We evaluated the indirect effects of plant diversity on litter decomposition in a tropical forest. We assessed diversity using different components (plant species richness, functional composition, and functional diversity), evaluated the environmental gradient (soil attributes, topography and canopy cover) and related it to the dynamics of litter decomposition. A 230-day in situ experiment was performed in the southern areas of the Brazilian Atlantic forest using litterbags filled with standard substrate (to test the indirect effects) to evaluate the decomposition rates. In parallel, we also conducted a taxonomic and functional survey of the vegetation in the area of influence of the decomposition experiment. We demonstrated that there is an indirect effect of plant diversity, via taxonomic and functional diversities, on litter decomposition. The indirect effect is more pronounced at the beginning of the decomposition process, and the influences of different components of diversity and ecological mechanisms (niche complementarity, mass effect and selection effect) vary over time. Our study revealed the importance of not only small-scale variations in the biotic component but also those of soil in ecosystem functioning in a megadiverse forest. In this way, we have contributed to a better understanding of the determinants of the decomposition process, in addition to those suggested by classical theoretical models (i.e., climate, litter composition and decomposers). [ABSTRACT FROM AUTHOR]

We present an efficient numerical method to quantify the spatial variation of glioma growth based on subject-specific medical images using a mechanically-coupled tumor model. The method is illustrated in a murine model of glioma in which we consider the tumor as a growing elastic mass that continuously deforms the surrounding healthy-appearing brain tissue. As an inverse parameter identification problem, we quantify the volumetric growth of glioma and the growth component of deformation by fitting the model predicted cell density to the cell density estimated using the diffusion-weighted magnetic resonance imaging data. Numerically, we developed an adjoint-based approach to solve the optimization problem. Results on a set of experimentally measured, in vivo rat glioma data indicate good agreement between the fitted and measured tumor area and suggest a wide variation of in-plane glioma growth with the growth-induced Jacobian ranging from 1.0 to 6.0. [ABSTRACT FROM AUTHOR]

The differential scanning calorimetry (DSC), microcalorimeter and cook-off (CO) oven are used to study the influence of mass on the thermal decomposition characteristics of ammonium nitrate (AN), and DSC and microcalorimenter are used to study the effect of thermal history on the thermal decomposition characteristics of AN. The results show that the mass has a significant effect on the thermal stability of AN, and the measured decomposition temperatures of samples, including onset decomposition temperature and peak decomposition temperature, decrease with the increase in their mass sizes. The large mass sample is easy to explode, which ultimately decreases the thermal stability of AN. The decomposition temperatures drifts to low temperature direction greater and greater with the increase in temperature. This is mainly due to the autocatalytic chemical reactions which generate intermediate products during heating. It is necessary to avoid the storage of large mass of AN and keep the heat source off the storage location in the process of industrial production and storage. [ABSTRACT FROM AUTHOR]

Mass effect after intracerebral hemorrhage (ICH) not only mechanically induces the brain damage, but also influences the progress of secondary brain damage. However, the influence of mass effect on the iron overload after ICH is still unclear. Here, a fixed volume of ferrous chloride solution and different volumes of poly(N-isopropylacrylamide) (PNIPAM) hydrogel were co-injected into the right basal ganglia of rats to establish the ICH model with certain degree of iron deposition but different degrees of mass effect. We found that mass effect significantly increased the iron deposition on neuronal cells at 6 h after ICH in a volume-dependent manner. Furthermore, the upregulation of Piezo-2, divalent metal transporter 1 (DMT1), transferrin receptor (TfR), and ferroptosis expressions were noted as the increase of mass effect. In addition, the pERK1/2 inhibitor PD98059 treated ICH rats reversed the upregulation of iron uptake protein and ferroptosis. Our findings revealed the relationship between mass effect and the iron uptake and ferroptosis, which are benefit to understand the brain damage process after ICH. • Mass effect exacerbated the neuronal iron deposition and the expression of iron uptake proteins. • Mass effect mediated the activation of the Piezo-2 and the phosphorylation of ERK1/2. • PD98059 could reverse the iron uptake proteins upregulation and ferroptosis. [ABSTRACT FROM AUTHOR]

Phytoplankton is a crucial primary producer in wetland ecosystems and is highly sensitive to changes in water quality. It has long been considered one of the most important biological indicators for monitoring water pollution. However, our understanding of the various aspects of phytoplankton communities assembly and the factors driving them remains limited. In this study, we conducted collection and analysis of phytoplankton samples from a temperate wetland cluster encompassing both lake and marsh types under the backdrop of industrial pollution from the petroleum industry. Our aim was to investigate the influence of spatial factors, land use patterns, and local environmental variables on the taxonomic and functional structure of the phytoplankton community, utilizing structural equation modeling (SEM) and variation partitioning. Our results revealed that environmental filtering exerts a greater relative impact on shaping the taxonomic composition of phytoplankton compared to mass effects. Human activities, such as industrial and agricultural production, can lead to landscape modifications that increase water nutrient levels and consequently influence the community composition. Taxonomic beta diversity is determined by both mass effects and environmental filtering. In contrast, functional beta diversity responds more to local environmental gradients, while the land use pattern was not important for facets of beta diversity in the wetland cluster. These results validate the concordance and complementarity between functional and taxonomy-based biome structures, highlighting the significance of integrating multiple ecological drivers. The results of this study contribute to a deeper understanding of wetland community assembly and the processes of biogeography, and are of crucial significance for the biological monitoring and management of freshwater ecosystem environmental pollution. [Display omitted] • Environmental filtering dominated in controlling community assembly in wetlands. • Different types of land use increase community heterogeneity among-wetland. • Wetland connectivity can exert controls on high dispersal rate community dynamics. • Taxonomic species replacements are less associated with turnover in functional traits. [ABSTRACT FROM AUTHOR]

Studying an opportunity to optimize the treatment of the patients with severe traumatic brain injuries is a topical issue in modern neurosurgery. Traumatic tension pneumocephalus is one of life-threatening conditions which accompanies severe TB1 and is often complicated with posttraumatic liquorrhea and mass effect. Materials and methods. We carried out systematic search in Russian and foreign medical databases (Medline, Russian Science Citation Index, EMedicine, UMKB) concerning our theme. We included the following words in our search request: tension pneumocephalus, mass effect, valve mechanism, treatment. The result of conducted review of literature was writing the clinic lecture, studying current status of the problem of etiopathogenesis, diagnostics and surveillance of the patients with tension pneumocephalus. The article presenas clinical case of successful surgical treatment of a patient with traumatic tension pneumocephalus. Conclusion. There are no uniform standards of urveillance of the patients with tension pneumocephalus. Based on our own experience, we determined that minimally invasive surgery is a method of choice among reconstructive craniofacial surgeries in the treatment of patients with traumatic tension pneumocephalus. It decreases the risks of intra- and postoperative complication. Compliance, using external ventricular drainage and repeated lumbar punctures with prevention of inflammatory complications helped stopping nasal liquorrhea and eliminating mass effect which caused absolute regression of neurological signs.

Although cerebral edema is a major cause of death and deterioration following hemispheric stroke, there remains no validated biomarker that captures the full spectrum of this critical complication. We recently demonstrated that reduction in intracranial cerebrospinal fluid (CSF) volume (∆CSF) on serial computed tomography (CT) scans provides an accurate measure of cerebral edema severity, which may aid in early triaging of stroke patients for craniectomy. However, application of such a volumetric approach would be too cumbersome to perform manually on serial scans in a real-world setting. We developed and validated an automated technique for CSF segmentation via integration of random forest (RF) based machine learning with geodesic active contour (GAC) segmentation. The proposed RF + GAC approach was compared to conventional Hounsfield Unit (HU) thresholding and RF segmentation methods using Dice similarity coefficient (DSC) and the correlation of volumetric measurements, with manual delineation serving as the ground truth. CSF spaces were outlined on scans performed at baseline (

Background and Purpose: Midline shift determined on magnetic resonance imaging (MRI) or computed tomography (CT) images is a well-validated marker of mass effect after large hemispheric infarction and associated with mortality. In this study, we targeted a population with moderately sized strokes. We compared midline shift to other imaging markers and determined their ability to predict long-term outcome.Methods: MRI scans were studied from the Echoplanar Imaging Thrombolysis Evaluation Trial (EPITHET) cohort. Midline shift, acute stroke lesion volume, lesional swelling volume, change in ipsilateral hemisphere volume, the ratio of ipsilateral to contralateral hemisphere volume, and the reduction in lateral ventricle volume were measured. The relationships of these markers with poor outcome (modified Rankin scale score 3-6 at day 90) were assessed. Receiver-operating characteristic (ROC) curves were generated to compare the performance of each metric.Results: Of the 71 included patients, 59.2% had a poor outcome that was associated with significantly larger values for midline shift, lesional swelling volume, and ratio of hemisphere volumes. Lesional swelling volume, change in hemisphere volume, ratio of hemisphere volumes, and lateral ventricle displacement were each correlated with midline shift (Spearman r = .60, .49, .61, and -.56, respectively; all P < .0001). ROC curve analysis showed that lesional swelling volume (area under the curve [AUC] = .791) predicted poor outcome better than midline shift (AUC = .682). For predicting mortality, ROC curve analysis showed that these three markers were equivalent.Conclusion: The ratio of ipsilateral to contralateral hemisphere volume, baseline lesion volume and lesional swelling volume best predicted poor outcome across a spectrum of stroke sizes. [ABSTRACT FROM AUTHOR]