Coordinated Movements Prevent Jamming in an Emperor Penguin Huddle

For Emperor penguins (Aptenodytes forsteri), huddling is the key to survival during the Antarctic winter. Penguins in a huddle are packed so tightly that individual movements become impossible, reminiscent of a jamming transition in compacted colloids. It is crucial, however, that the huddle structure is continuously reorganized to give each penguin a chance to spend sufficient time inside the huddle, compared with time spent on the periphery. Here we show that Emperor penguins move collectively in a highly coordinated manner to ensure mobility while at the same time keeping the huddle packed. Every 30–60 seconds, all penguins make small steps that travel as a wave through the entire huddle. Over time, these small movements lead to large-scale reorganization of the huddle. Our data show that the dynamics of penguin huddling is governed by intermittency and approach to kinetic arrest in striking analogy with inert non-equilibrium systems, including soft glasses and colloids

Pan-cancer analysis of whole genomes

Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

Relação entre qualidade de vida e auto-percepção da qualidade vocal de pacientes laringectomizados totais: estudo piloto Relation between life quality and self-perception of vocal quality in total laryngectomized patients: pilot study

OBJETIVO: investigar os indicativos da qualidade de vida em indivíduos submetidos a laringectomia total e a relação destes com os aspectos perceptivo-auditivos da qualidade vocal. MÉTODOS: a população estudada foi constituída por seis indivíduos laringectomizados totais com idades compreendidas entre 40 e 60 anos, de ambos os gêneros, falantes por meio da fala esofágica ou traqueoesofágica. Foram aplicados o protocolo Qualidade de Vida e Voz (QVV) (Behlau et al., 2001) e um roteiro escala de fluência (Robe et al.,1956) para julgamentos de estudantes de graduação e pós-graduação em Fonoaudiologia; e roteiro de auto-percepção da voz para julgamentos dos laringectomizados totais. RESULTADOS: os valores do Domínio Físico do QVV foram em média 63.19 e no Domínio Sócio-Emocional 80.20, tendo como máximo 100. Os sujeitos que apresentaram um escore global baixo são aqueles que sentem um maior desconforto na voz, referido como tensão e rouquidão e os juízes classificaram como sujeitos com limitações para se comunicar. Os sujeitos com valores do escore global alto possuem uma melhor percepção de sua voz e fizeram fonoterapia, tendo sido classificados pelo grupo de juízes como bons falantes que conseguem emitir sentenças ou possuem uma fala fluente, sem hesitação. CONCLUSÃO: o escore no Domínio Físico foi maior do que no Domínio Sócio-Emocional, e tais dados revelam que o desconforto maior apresenta-se no Domínio Físico. Os julgamentos efetuados pelos profissionais e pelos laringectomizados totais correlacionaram-se entre si e com o QVV.<br>PURPOSE: to investigate life quality indications in individuals that underwent a total laryngectomy and their relationship with the vocal quality hearing-perceptive aspects. METHODS: the studied population was made up by six total laryngectomized individuals between 40 and 60-year old, of both genders, esophageal or tracheae-esophageal speech speakers. Life and Voice Quality (QVV) protocol (Behlau et al., 2001) and a fluency scale guide (Robe et al. ,1956) were applied for trials of Speech Therapy graduation and post-graduation students; and voice self-perception guide for trials of total laryngectomized individuals. RESULTS: the values for Physical Dominion of QVV were on average 63.19 and in the Social-Emotional Dominion 80.20, considering 100 as threshold. The subjects that showed a low global score are those that feel a major voice discomfort, referred to as tension and hoarseness and that the examiners classified as subjects with limitations to communicate. The subjects with values within the global high score have a better perception of their voice and underwent speech therapy, having been classified by the group of examiners as good speakers who get to give out sentences or have a fluent speech, with no hesitation. CONCLUSION: the score in the Physical Dominion was higher than in the Social-Emotional Dominion, and such data show that the major discomfort appears in the Physical Dominion. The trials carried through by the professionals and by the total laryngectomized individuals were correlated amongst themselves and with QVV

Statistical Dynamics of Flowing Red Blood Cells by Morphological Image Processing

Blood is a dense suspension of soft non-Brownian cells of unique importance. Physiological blood flow involves complex interactions of blood cells with each other and with the environment due to the combined effects of varying cell concentration, cell morphology, cell rheology, and confinement. We analyze these interactions using computational morphological image analysis and machine learning algorithms to quantify the non-equilibrium fluctuations of cellular velocities in a minimal, quasi-two-dimensional microfluidic setting that enables high-resolution spatio-temporal measurements of blood cell flow. In particular, we measure the effective hydrodynamic diffusivity of blood cells and analyze its relationship to macroscopic properties such as bulk flow velocity and density. We also use the effective suspension temperature to distinguish the flow of normal red blood cells and pathological sickled red blood cells and suggest that this temperature may help to characterize the propensity for stasis in Virchow's Triad of blood clotting and thrombosis