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Background Most sarcomas metastasize predominantly to the lungs, and chest x-ray, or computed tomography, is the most commonly used staging investigation. Myxoid liposarcomas (MLSs) are rare tumors with a tendency to metastasize to extrapulmonary loci. The aim of this study was to assess the locations of the first metastases in MLS patients, to guide the design of effective staging and follow-up imaging protocols. Methods Patients treated for MLS between 1987 and 2017 were identified in a prospectively maintained register. Histology of the tumors was reassessed. In addition, the presence of one of the pathognomonic gene translocations was confirmed, uniquely for a retrospective series. The surgical and oncological outcomes were reviewed. A comprehensive review of the literature was performed on the metastatic pattern of MLS, including series with 10 or more MLS patients with metastatic disease. Results A total of 32 patients with genetically confirmed MLS were identified, with a median follow-up of 7.6 years. Seven patients (22%) developed metastatic disease, five initially intra-abdominally and only one to the lungs. The comprehensive review included 14 series with 1853 patients, 348 (19%) of whom had metastases. The location of the first metastases was soft tissues in 32% of patients, intra-abdominal in 26%, pulmonary in 24%, and bone in 17%. Conclusions MLSs metastasize often intra-abdominally and to extra-abdominal soft tissues. Thus, whole-body imaging may be indicated during the initial assessment and follow-up of these patients.

Population isolates such as those in Finland benefit genetic research because deleterious alleles are often concentrated on a small number of low-frequency variants (0.1% ≤ minor allele frequency < 5%). These variants survived the founding bottleneck rather than being distributed over a large number of ultrarare variants. Although this effect is well established in Mendelian genetics, its value in common disease genetics is less explored1,2. FinnGen aims to study the genome and national health register data of 500,000 Finnish individuals. Given the relatively high median age of participants (63 years) and the substantial fraction of hospital-based recruitment, FinnGen is enriched for disease end points. Here we analyse data from 224,737 participants from FinnGen and study 15 diseases that have previously been investigated in large genome-wide association studies (GWASs). We also include meta-analyses of biobank data from Estonia and the United Kingdom. We identified 30 new associations, primarily low-frequency variants, enriched in the Finnish population. A GWAS of 1,932 diseases also identified 2,733 genome-wide significant associations (893 phenome-wide significant (PWS), P < 2.6 × 10-11) at 2,496 (771 PWS) independent loci with 807 (247 PWS) end points. Among these, fine-mapping implicated 148 (73 PWS) coding variants associated with 83 (42 PWS) end points. Moreover, 91 (47 PWS) had an allele frequency of

Varicose veins is the most common manifestation of chronic venous disease that displays female-biased incidence. To identify protein-inactivating variants that could guide identification of drug target genes for varicose veins and genetic evidence for the disease prevalence difference between the sexes, we conducted a genome-wide association study of varicose veins in Finns using the FinnGen dataset with 17,027 cases and 190,028 controls. We identified 50 associated genetic loci (P −8) of which 29 were novel including one near ERG with female-specificity (rs2836405-G, OR[95% CI] = 1.09[1.05–1.13], P = 3.1 × 10−8). These also include two X-chromosomal (ARHGAP6 and SRPX) and two autosomal novel loci (TGFB2 and GJD3) with protein-coding lead variants enriched above 56-fold in Finns over non-Finnish non-Estonian Europeans. A low-frequency missense variant in GJD3 (p.Pro59Thr) is exclusively associated with a lower risk for varicose veins (OR = 0.62 [0.55–0.70], P = 1.0 × 10−14) in a phenome-wide scan of the FinnGen data. The absence of observed pleiotropy and its membership of the connexin gene family underlines GJD3 as a potential connexin-modulating therapeutic strategy for varicose veins. Our results provide insights into varicose veins etiopathology and highlight the power of isolated populations, including Finns, to discover genetic variants that inform therapeutic development.

BackgroundTestosterone levels are linked with diverse characteristics of human health, yet, whether these associations reflect correlation or causation remains debated. Here, we provide a broad perspective on the role of genetically determined testosterone on complex diseases in both sexes.MethodsLeveraging genetic and health registry data from the UK Biobank and FinnGen (total N = 625,650), we constructed polygenic scores (PGS) for total testosterone, sex-hormone binding globulin (SHBG) and free testosterone, associating these with 36 endpoints across different disease categories in the FinnGen. These analyses were combined with Mendelian Randomization (MR) and cross-sex PGS analyses to address causality.ResultsWe show testosterone and SHBG levels are intricately tied to metabolic health, but report lack of causality behind most associations, including type 2 diabetes (T2D). Across other disease domains, including 13 behavioral and neurological diseases, we similarly find little evidence for a substantial contribution from normal variation in testosterone levels. We nonetheless find genetically predicted testosterone affects many sex-specific traits, with a pronounced impact on female reproductive health, including causal contribution to PCOS-related traits like hirsutism and post-menopausal bleeding (PMB). We also illustrate how testosterone levels associate with antagonistic effects on stroke risk and reproductive endpoints between the sexes.ConclusionsOverall, these findings provide insight into how genetically determined testosterone correlates with several health parameters in both sexes. Yet the lack of evidence for a causal contribution to most traits beyond sex-specific health underscores the complexity of the mechanisms linking testosterone levels to disease risk and sex differences.Plain language summaryHormones, such as testosterone, travel around the body communicating between the different parts. Testosterone is present at higher levels in men, but also present in women. Variable testosterone levels explain some differences in human traits and disease prevalence. Here, we study how adult testosterone levels relate to health and disease. Genetic, i.e. inherited, differences in testosterone levels contribute to many traits specific to men or women, such as women's reproductive health, hormonal cancers, and hair growth typical in males. However, testosterone levels do not appear as a major cause of most traits studied, including psychiatric diseases and metabolic health. Normal variation in baseline testosterone levels thus seems to have a relatively minor impact on health and disease.Leinonen et al. investigate correlations between testosterone levels and disease using genetic and health registry data from the UK Biobank and FinnGen. There is a lack of evidence for normal variation in testosterone levels having a causal contribution to most non-sex-specific traits.

BackgroundFew studies have focused on patient-related factors in analyzing long-term functional outcome and health-related quality of life (HRQoL) in patients with postoperative lower extremity soft tissue sarcoma (STS).ObjectiveThe purpose of this study was to investigate factors associated with postoperative functional outcome and HRQoL in patients with lower extremity STS.MethodsThis cross-sectional study was performed in a tertiary referral center using the Toronto Extremity Salvage Score (TESS), Quality-of-Life Questionnaire (QLQ)-C30 and 15 Dimension (15D) measures. Functional outcome and HRQoL data were collected prospectively. All patients were treated by a multidisciplinary team according to a written treatment protocol.ResultsA total of 141 patients who had undergone limb-salvage surgery were included. Depending on the outcome measure used, 19–51% of patients were completely asymptomatic and 13–14% of patients had an unimpaired HRQoL. The mean score for TESS, 15D mobility score, and QLQ-C30 Physical Functioning scale were 86, 0.83, and 75, respectively, while the mean score for 15D was 0.88, and 73 for QLQ-C30 QoL. Lower functional outcome was statistically significantly associated with higher age, higher body mass index (BMI), and the need for reconstructive surgery and radiotherapy, while lower HRQoL was statistically significantly associated with higher age, higher BMI, and reconstructive surgery.ConclusionFunctional outcome and HRQoL were generally high in this cross-sectional study of patients with STS in the lower extremity. Both tumor- and treatment-related factors had an impact but patient-related factors such as age and BMI were the major determinants of both functional outcome and HRQoL.

BackgroundRadiation-associated angiosarcoma of the breast (RAASB) is an aggressive malignancy that is increasing in incidence. Only a few previous population-based studies have reported the results of RAASB treatment.MethodsA search for RAASB patients was carried out in the Finnish Cancer Registry, and treatment data were collected to identify prognostic factors for survival.ResultsOverall, 50 RAASB patients were identified. The median follow-up time was 5.4 years (range 0.4–15.6), and the 5-year overall survival rate was 69%. Forty-seven (94%) patients were operated on with curative intent. Among these patients, the 5-year local recurrence-free survival, distant recurrence-free survival, and overall survival rates were 62%, 75%, and 74%, respectively. A larger planned surgical margin was associated with improved survival.ConclusionsWe found that the majority of RAASB patients were eligible for radical surgical management in this population-based analysis. With radical surgery, the prognosis is relatively good.

Background Treatment of gunshot wounds of the brain (GSWB) remains controversial and there is high variation in reported survival rates (from 90%) depending on the etiology and country. We retrospectively analyzed the outcome of a series of consecutive GSWB patients admitted alive to a level 1 trauma center in a safe high-income welfare country with a low rate of homicidal gun violence. Methods Patients admitted due to a GSWB to the HUS Helsinki University Hospital during 2000–2012 were identified from hospital discharge registry and log books of the emergency room and ICU. CT scans and medical records of these patients were reviewed. Univariate analysis and backward logistic regression were performed, and their results compared with that of a systematic literature review of factors related to the outcome of GSWB patients. Results Sixty-four patients admitted alive after GSWB were identified. Eighty percent had self-inflicted GSWB, 81% were contact shots, and 70% were caused by handguns. In-hospital mortality was 72%. Factors associated with mortality in our series were low GCS (≤ 8) at admission, transventricular bullet trajectory, and associated damage to deep brain structures, as reported before in the literature. Of the 64 patients admitted alive, 42% (27/64) were admitted to ICU, 34% (22/64) underwent surgery, and in 25% (16/64), craniotomy and hematoma evacuation was performed. Mortality in the surgically treated group was 32% but near 100% without surgery and ICU treatment. Median GOS in the surgically treated patients was 3 (range 1–5). Conclusions GSWB caused by contact shot from handguns has a high mortality rate, but can be survived with reasonable outcome if limited to lobar injury without significant damage to deep brain structures or brain stem. In such GSWB patients, initial aggressive resuscitation, ICU admission, and surgery seem indicated. Electronic supplementary material The online version of this article (10.1007/s00701-019-03952-y) contains supplementary material, which is available to authorized users.

A numerical study of metal front contacts grid spacing for photovoltaic (PV) converter of relatively small area is presented. The model is constructed based on Solcore, an open-source Python-based library. A three-step-process is developed to create a hybrid quasi-3D model. The grid spacing under various operating conditions was assessed for two similar p–n and n–p structures. The key target was finding optimal configuration to achieve the highest conversion efficiency at different temperatures and illumination profiles. The results show that the n–p structure yields wider optimal spacing range and the highest output power. Also, it was found that temperature increase and illumination nonuniformity results in narrower optimal spacing for both structure architectures. Analyzing the current–voltage characteristics, reveals that resistive losses are the dominant loss mechanism bringing restriction in terms of ability to handle nonuniform illumination.

Context: ‘Conserving Nature’s stage’ has been advanced as an important conservation principle because of known links between biodiversity and abiotic environmental diversity, especially in sensitive high-latitude environments and at the landscape scale. However these links have not been examined across gradients of human impact on the landscape. Objectives: To (1) analyze the relationships between land-use intensity and both landscape-scale biodiversity and geodiversity, and (2) assess the contributions of geodiversity, climate and spatial variables to explaining vascular plant species richness in landscapes of low, moderate and high human impact. Methods: We used generalized additive models (GAMs) to analyze relationships between land-use intensity and both geodiversity (geological, geomorphological and hydrological richness) and plant species richness in 6191 1-km² grid squares across Finland. We used linear regression-based variation partitioning (VP) to assess contributions of climate, geodiversity and spatial variable groups to accounting for spatial variation in species richness. Results: In GAMs, geodiversity correlated negatively, and plant species richness positively, with land-use intensity. Both relationships were non-linear. In VP, geodiversity best accounted for species richness in areas of moderate to high human impact. These overall contributions were mainly due to variation explained jointly with climate, which dominated the models. Independent geodiversity contributions were highest in pristine environments, but low throughout. Conclusions: Human action increases biodiversity but may reduce geodiversity, at landscape scale in high-latitude environments. Better understanding of the connections between biodiversity and abiotic environment along changing land-use gradients is essential in developing sustainable measures to conserve biodiversity under global change.

Educational data mining (EDM) processes have shifted towards open-ended processes with visualizations and parameter and predictive model adjusting. Data and models in hyperdimensions can be visualized for end-users with popular data mining platforms such as Weka and RapidMiner. Multiple studies have shown how the adjusting and even creating the decision tree classifiers help EDM end-users to better comprehend the dataset and the context where the data has been collected. To harness the power of such open-ended approach in EDM, we introduce a novelAugmented Intelligencemethod and a cluster analysis algorithmNeural N-Tree. These contributions allow EDM end-users to analyze educational data in an iterative process where the knowledge discovery and the accuracy of the predictive model generated by the algorithm increases over time through the interactions between the models and the end-users. In contrast to other similar approaches, the key in our method is in the model adjusting and not in parameter tuning. We report a study where the potential EDM end-users clustered data from an education setting and interacted with Neural N-Tree models by following Augmented Intelligence method. The findings of the study suggest that the accuracy of the models evolve over time and especially the end-users who have a adequate level of knowledge from data mining benefit from the method. Moreover, the study indicates that the knowledge discovery is possible through AUI.

A single-institution series using a (neo)adjuvant chemotherapy and interdigitated hyperfractionated split-course radiation therapy (CRT) treatment protocol for soft tissue sarcoma was reviewed. Our specific aims were to study recurrence rates and long-term toxicity. Between 1998 and 2016, 89 patients with non-metastatic soft tissue sarcoma were treated with surgery combined with six courses of doxorubicin and ifosfamide and hyperfractionated radiation therapy (42–60 Gy/1.5 Gy twice daily). Patients were considered being at high risk if tumour malignancy grade was high and the tumour fulfilled at least two of the following criteria: size >8 cm, presence of necrosis or vascular invasion. The mean age of the patients was 50.7 years. With a median follow-up of 5.4 years for survivors, the local control rate was 81.4%. Six (7%) patients progressed during neoadjuvant CRT. Seven (8%) patients discontinued the treatment due to toxicity. Eighty-six patients were operated and three (3%) of these developed a long-term complication. The estimated metastasis-free survival was 47.6% and overall survival 53.0% at five years. The limb-salvage rate was 93%. The limb-salvage rate, local control and complication rates were good in these patients with high risk soft tissue sarcoma. Metastases-free survival and overall survival rates were less satisfactory, reflecting the aggressive nature of these tumours.

The aim of the present study was to investigate the effect of moisture content and temperature on the fracture behaviour of thermally modified Norway spruce (Picea abies [L.] Karst.) in the transverse plane. Spruce was thermally modified at two heat treatment temperatures, 190 and 210 °C. Mode I fracture tests were carried out at temperatures of 22 and 50 °C on air-dried and fully water-saturated (>fibre saturation point) material. Small CT specimens were used, and load–CMOD curves were recorded. Characteristic fracture parameters were calculated. The fracture surfaces were subsequently examined using optical microscopy. Thermal modification altered all the calculated fracture parameter values and the changes increased as the severity of heat treatment increased. The parameters were altered more in the radial-tangential (RT) than in tangential-radial (TR) orientation. The failure mode changed due to heat treatment in the TR orientation but in the RT orientation the failure mode of unmodified and heat treated material differs only at high moisture content and elevated temperature.

We compared the clinical findings and survival in patients with Mycobacterium avium complex (MAC) and other non-tuberculous mycobacteria (NTM). A total of 167 adult non-human immunodeficiency virus (HIV) patients with at least one positive culture for NTM were included. Medical records were reviewed. The patients were categorised according to the 2007 American Thoracic Society (ATS) criteria. MAC comprised 59 % of all NTM findings. MAC patients were more often female (70 % vs. 34 %, p

We study the limitations of deterministic programmability of quantum circuits, e.g., quantum computer. More precisely, we analyse the programming of quantum observables and channels via quantum multimeters. We show that the programming vectors for any two different sharp observables are necessarily orthogonal, whenever post-processing is not allowed. This result then directly implies that also any two different unitary channels require orthogonal programming vectors. This approach generalizes the well-known orthogonality result first proven by Nielsen and Chuang. In addition, we give size-bounds for a multimeter to be efficient in quantum programming., Comment: Corrected version V2

Developments in micro-neurosurgical microscopes have improved operating precision and ensured the quality of outcomes. Using the stereoscopic magnified view, however, necessitates frequent manual adjustments to the microscope during an operation.This article reports on an investigation of the interaction details concerning a state-of-the-art micro-neurosurgical microscope. The video data from detailed observations of neurosurgeons' interaction patterns with the microscope were analysed to examine disruptive events caused by adjusting the microscope.The primary findings show that interruptions caused by adjusting the microscope handgrips and mouth switch prolong the surgery time up to 10%. Surgeons, we observed, avoid interaction with the microscope's controls, settings, and configurations by working at the edge of the view, operating on a non-focused view, and assuming unergonomic body postures.The lack of an automatic method for adjusting the microscope is a major problem that causes interruptions during micro-neurosurgery. From this understanding of disruptive events, we discuss the opportunities and limitations of interactive technologies that aim to reduce the frequency or shorten the duration of interruptions caused by microscope adjustment.

Protein-truncating variants protective against human disease provide in vivo validation of therapeutic targets. Here we used targeted sequencing to conduct a search for protein-truncating variants conferring protection against inflammatory bowel disease exploiting knowledge of common variants associated with the same disease. Through replication genotyping and imputation we found that a predicted protein-truncating variant (rs36095412, p.R179X, genotyped in 11,148 ulcerative colitis patients and 295,446 controls, MAF=up to 0.78%) in RNF186, a single-exon ring finger E3 ligase with strong colonic expression, protects against ulcerative colitis (overall P=6.89 × 10(-7), odds ratio=0.30). We further demonstrate that the truncated protein exhibits reduced expression and altered subcellular localization, suggesting the protective mechanism may reside in the loss of an interaction or function via mislocalization and/or loss of an essential transmembrane domain.

Merkel cell carcinoma (MCC) is an aggressive dermal tumour of neuroendocrine origin. The recently found Merkel cell polyomavirus (MCV) integrates clonally in the tumour genome, which suggests an important role in the pathogenesis of the disease. Previous small-scale studies have detected anti-apoptotic protein bcl-2 in 80 % of MCC tumours, but its correlation to the prognosis of MCC remains controversial. Our aim was to clarify the correlation of immunohistochemical expression of bcl-2 to MCV presence and MCC prognosis. We analyzed 116 primary MCC specimens with corresponding clinical data by immunohistochemistry for bcl-2. The presence of MCV DNA had been analyzed by quantitative PCR for 108 tumours. The correlations were analyzed statistically. Of the primary MCC samples, 85 % were bcl-2 positive. No significant differences in MCV DNA occurred between the bcl-2-positive and bcl-2-negative tumours. Local and systemic metastasis was more common in patients with bcl-2 negative tumours (33 %) than in patients with bcl-2-positive tumours (12 %; p = 0.04) at the time of diagnosis. The mean overall survival was higher in patients with bcl-2-positive tumours than of those with negative tumours (mean survival 1,814 days (5.0 years) vs. 769 days (2.1 years), p = 0.01). Bcl-2 positivity indicates better clinical stage at the time of diagnosis and a longer survival in MCC.

BACKGROUND: We developed a web-based, prognostic tool for extremity and trunk wall soft tissue sarcoma to predict 10-year sarcoma-specific survival. External validation was performed. METHODS: Patients referred during 1987-2002 to Helsinki University Central Hospital are included. External validation was obtained from the Lund University Hospital register. Cox proportional hazards models were fitted with the Helsinki data. The previously described model (SIN) includes size, necrosis, and vascular invasion. The extended model (SAM) includes the SIN factors and in addition depth, location, grade, and size on a continuous scale. Models were statistically compared according to accuracy (area under the ROC curve = AUC) of 10-year sarcoma-specific survival prediction. RESULTS: The AUC of the SAM model in 10-year survival prediction in the Helsinki patient series was 0.81 as compared with 0.74 for the SIN model (P = 0.0007). The corresponding AUCs in the external validation series were 0.77 for the SAM model and 0.73 for the SIN model (P = 0.03). A web-based calculator for the SAM model is available at http://www.prognomics.org/sam. CONCLUSION: Addition of grade, depth, and location as well as tumour size on a continuous scale significantly improved the accuracy of the prognostic model when compared with a model that includes only size, necrosis, and vascular invasion. British Journal of Cancer (2012) 106, 1076-1082. doi:10.1038/bjc.2012.48 www.bjcancer.com Published online 21 February 2012 (C) 2012 Cancer Research UK

Planned ventral hernia is a management strategy in which the abdominal fascial layer has been left unclosed and the viscera are covered only with original or grafted skin. Leaving the fascia open can be deliberate or unavoidable and most commonly results from staged repair of the abdominal wall due to trauma, peritonitis, pancreatitis, abdominal vascular emergencies, or abdominal compartment syndrome. The abdominal wall defects can be categorized as type I or II defects depending on whether there is intact, stable skin coverage. In defects with intact skin coverage, the most commonly used methods are the components separation technique and a prosthetic repair, sometimes used in combination. The advantages of the components separation technique is the ability to close the linea alba at the midline, creating a better functional result than a repair with inert mesh. Although the reherniation risk seems higher after components separation, the risk of infection is considerably lower. With a type II defect, with absent or unstable skin coverage, fascial repair alone is inadequate. Of the more complex reconstruction techniques, the use of a free tensor fasciae latae (TFL) flap utilizing a saphenous vein arteriovenous loop is the most promising. The advantages of the TFL flap include constant anatomy of the pedicle, a strong fascial layer, large-caliber vessels matching the size of the AV loop, and the ability to use large flaps (up to 20 × 35 cm). Whatever technique is used, the repair of complex abdominal wall defects requires close collaboration with plastic and abdominal surgeons, which is best managed in specialized centers.

Merkel cell carcinoma (MCC) is a rare neuroendocrine carcinoma typically affecting the elderly. Only 5% to 10% of the patients are younger than 50 years at the time of the diagnosis. The purpose of this study was to compare the tumour and disease characteristics between exceptionally young and the typical elderly MCC population. Further, quantitative polymerase chain reaction analysis was used to study for Merkel cell polyomavirus (MCPyV) in their primary MCC tumours. Patients diagnosed with MCC in Finland from 1979 to 2004 were identified from the files of the Finnish Cancer Registry. Presence of MCPyV DNA in tumour samples was investigated using quantitative polymerase chain reaction. Six of 181 MCC patients were ≤50 years, with male-to-female ratio of 1:1. An altered immune condition state was observed in five patients. The Kaplan–Meier analysis showed a trend towards worse MCC-specific survival both in 5- and 10-year surveillance for younger patients. Five primary tumour tissue samples, available for analysis, contained MCPyV DNA. Our data shows that MCC, ≤50 years of age, is rarer then previously estimated. Moreover, our data showed marked differences both in patient demographics and in primary tumour characteristics as compared to surveys including older MCC patients. Course of disease seemed to be worse in the exceptionally young patients. All MCC primary tumours in this study contained MCPyV DNA.

Nature 550, 244–248 (2017); doi:10.1038/nature24265 In this Letter, the Source Data associated with Fig. 2a and d were incorrect. This was due to an error during manuscript preparation, when transformed data instead of the raw values plotted in the figure were included in the Source Data file. The figure panels are correct and remain unchanged, and these errors do not affect the results or conclusions of the Letter.

Background: Immunosuppression and Merkel-cell polyomavirus (MCPyV) infection may have a role in the pathogenesis of Merkel-cell carcinoma (MCC), a rare neuroendocrine carcinoma of the skin. Methods: We studied incidence of chronic lymphocytic leukaemia (CLL) and MCC from the files of the Finnish Cancer Registry and the largest hospital of Finland, Helsinki University Central Hospital, from 1979 to 2006. Presence of MCPyV DNA in MCCs was investigated by quantitative PCR. Results: We identified 4164 patients diagnosed with CLL and 172 diagnosed with MCC. Six patients diagnosed with both diseases were found; CLL was the first diagnosis in four cases and MCC in two. The standardised incidence ratio (SIR) for CLL after the diagnosis of MCC was highly elevated, 17.9 (95% confidence interval (CI), 2.2–64.6; P

The increase in semiconductor conductivity that occurs when a hard indenter is pressed into its surface has been recognized for years, and nanoindentation experiments have provided numerous insights into the mechanical properties of materials. In particular, such experiments have revealed so called pop-in events, where the indenter suddenly enters deeper into the material without any additional force being applied; these mark the onset of the elastic-plastic transition. Here, we report the observation of a current spike--a sharp increase in electrical current followed by immediate decay to zero at the end of the elastic deformation--during the nanoscale deformation of gallium arsenide. Such a spike has not been seen in previous nanoindentation experiments on semiconductors, and our results, supported by ab initio calculations, suggest a common origin for the electrical and mechanical responses of nanodeformed gallium arsenide. This leads us to the conclusion that a phase transition is the fundamental cause of nanoscale plasticity in gallium arsenide, and the discovery calls for a revision of the current dislocation-based understanding of nanoscale plasticity.