Avoiding catastrophic failure in correlated networks of networks

Networks in nature do not act in isolation but instead exchange information, and depend on each other to function properly. An incipient theory of Networks of Networks have shown that connected random networks may very easily result in abrupt failures. This theoretical finding bares an intrinsic paradox: If natural systems organize in interconnected networks, how can they be so stable? Here we provide a solution to this conundrum, showing that the stability of a system of networks relies on the relation between the internal structure of a network and its pattern of connections to other networks. Specifically, we demonstrate that if network inter-connections are provided by hubs of the network and if there is a moderate degree of convergence of inter-network connection the systems of network are stable and robust to failure. We test this theoretical prediction in two independent experiments of functional brain networks (in task- and resting states) which show that brain networks are connected with a topology that maximizes stability according to the theory.Comment: 40 pages, 7 figure

Spinning strings and integrable spin chains in the AdS/CFT correspondence

In this introductory review we discuss dynamical tests of the AdS_5 x S^5 string/N=4 super Yang-Mills duality. After a brief introduction to AdS/CFT we argue that semiclassical string energies yield information on the quantum spectrum of the string in the limit of large angular momenta on the S^5. The energies of the folded and circular spinning string solutions rotating on a S^3 within the S^5 are derived, which yield all loop predictions for the dual gauge theory scaling dimensions. These follow from the eigenvalues of the dilatation operator of N=4 super Yang-Mills in a minimal SU(2) subsector and we display its reformulation in terms of a Heisenberg s=1/2 spin chain along with the coordinate Bethe ansatz for its explicit diagonalization. In order to make contact to the spinning string energies we then study the thermodynamic limit of the one-loop gauge theory Bethe equations and demonstrate the matching with the folded and closed string result at this loop order. Finally the known gauge theory results at higher-loop orders are reviewed and the associated long-range spin chain Bethe ansatz is introduced, leading to an asymptotic all-loop conjecture for the gauge theory Bethe equations. This uncovers discrepancies at the three-loop order between gauge theory scaling dimensions and string theory energies and the implications of this are discussed. Along the way we comment on further developments and generalizations of the subject and point to the relevant literature.Comment: 40 pages, invited contribution to Living Reviews in Relativity. v2: improvements in the text and references adde

An Extended Photoperiod Increases Milk Yield and Decreases Ovulatory Activity in Dairy Goats

Short day length is associated with reduced milk production in dairy ruminants. Dairy ruminants have been kept in lit sheds during winter to extend the day length and stimulate milk production. However, there studies are few on the effect of an extended photoperiod on the ensuing reproductive performance of dairy goats. The aim of this study was to examine the effect of long day photoperiod (LDPP) and exposure to bucks on milk production and plasma progesterone and prolactin in dairy goats. The study was conducted in 122 non-pregnant lactating dairy goats over 18 weeks from April to August (late autumn and winter in the Southern Hemisphere). The goats were kept in open sided sheds in which the control treatment received ambient lighting while the LDPP treatment received 16 h of light, including artificial lighting. In June, July and August synchronised does were randomly assigned each month to the presence or absence of a buck and ovulatory activity determined from plasma progesterone. Plasma progesterone concentrations were reduced (0.73 vs. 0.46 pmol, p < 0.001) while prolactin concentrations were increased (0.095 vs. 1.33 ng/mL, p < 0.001) in LDPP goats. The former response was most marked in late winter (0.58 vs. 0.004 pmol, p < 0.001) indicating a lack of functional corpora lutea. While there was no overall effect of buck exposure on plasma progesterone concentrations there was a three-way interaction such that plasma progesterone concentrations were increased (p < 0.05) by exposure to bucks in LDPP goats in August (late winter) but not at other times. Milk production was increased in LDPP goats over the latter stages of the study (1. 55 vs. 1.82 L/d, p < 0.05). Also, persistency of lactation was greater in LDPP goats with fewer goats drying off (13 vs. 0%, p < 0.05). These findings suggest that LDPP can increase milk production and persistence while decreasing ovulatory activity in dairy goats

Questionnaire Hearing Handicap Inventory for the Elderly - Screening version (HHIE-S): sensitivity and specificity study

PURPOSE: To investigate the sensitivity and specificity of the questionnaire Hearing Handicap Inventory for the Elderly - Screening version (HHIE-S) in the hearing screening of elderly people who seek for different health care services (audiological clinic and other clinics). METHODS: The hearing of 78 elderly - 23 attended at the Discipline of Geriatrics and Gerontology of the institution who did not, necessarily, have complaints regarding their hearing, and 55 attended at the Audiology Clinic of the same institution with complaints related to the auditory and/or vestibular systems - was assessed. The HHIE-S questionnaire was applied, and its total score was divided into three categories, according to the handicap perception. RESULTS: A statistically significant relationship was found between handicap and degree of hearing loss in both patients from the Audiology Clinic (p=0.009*) and from the Geriatrics Clinic (p=0.002). In the first group, the HHIE-S questionnaire showed low sensitivity (23.5%) and high specificity (73.7%). In the group of patients from the Geriatrics Clinic, the values of sensitivity (94.7%) and specificity (75%) were both high. CONCLUSIONS: There was positive association between the degree of hearing loss and the handicap referred by both groups of subjects. The HHIE-S questionnaire is a hearing screening instrument with high sensitivity and specificity in identifying hearing loss in elderly people that seek health care services that are not specific for attention related to hearing disorders.OBJETIVO: Investigar a sensibilidade e especificidade do questionário Hearing Handicap Inventory for the Elderly - Screening version (HHIE-S) na triagem auditiva de idosos que procuram diferentes serviços de atenção à saúde (clínica audiológica e outras clínicas). MÉTODOS: Foi avaliada a audição de 78 idosos - 23 atendidos na disciplina de Geriatria e Gerontologia da instituição de origem, que não tinham, necessariamente, queixas relacionadas à audição, e 55 atendidos no Ambulatório de Audiologia da mesma instituição, com queixas relacionadas aos sistemas auditivo e/ou vestibular. Foi aplicado o HHIE-S, cujo escore total foi dividido em três categorias, de acordo com a percepção do handicap. RESULTADOS: Houve relação estatisticamente significante entre handicap e grau de perda auditiva no grupo de pacientes do Ambulatório de Audiologia (p=0,009), e no grupo de pacientes do Ambulatório de Geriatria (p=0,002). No primeiro grupo, o questionário HHIE-S revelou baixa sensibilidade (23,5%) e alta especificidade (73,7%). No grupo de pacientes do setor de Geriatria, foram altos os valores de sensibilidade (94,7%) e de especificidade (75%). CONCLUSÕES: Há associação positiva entre o grau de perda auditiva e o handicap referido em ambos os grupos. O questionário HHIE-S é um instrumento de triagem auditiva com alta especificidade e sensibilidade na identificação de perdas auditivas em idosos que procuram serviços de saúde que não são específicos para atendimentos relacionados às alterações auditivas.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Irmandade da Santa Casa de Misericórdia de São PauloUniversidade Federal de São Paulo (UNIFESP)Universidade Federal de São Paulo (UNIFESP) Departamento de FonoaudiologiaUNIFESP, Depto. de FonoaudiologiaSciEL

Performance of the CMS Cathode Strip Chambers with Cosmic Rays

The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

Regulation of mammary gland branching morphogenesis by the extracellular matrix and its remodeling enzymes.

A considerable body of research indicates that mammary gland branching morphogenesis is dependent, in part, on the extracellular matrix (ECM), ECM-receptors, such as integrins and other ECM receptors, and ECM-degrading enzymes, including matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs). There is some evidence that these ECM cues affect one or more of the following processes: cell survival, polarity, proliferation, differentiation, adhesion, and migration. Both three-dimensional culture models and genetic manipulations of the mouse mammary gland have been used to study the signaling pathways that affect these processes. However, the precise mechanisms of ECM-directed mammary morphogenesis are not well understood. Mammary morphogenesis involves epithelial 'invasion' of adipose tissue, a process akin to invasion by breast cancer cells, although the former is a highly regulated developmental process. How these morphogenic pathways are integrated in the normal gland and how they become dysregulated and subverted in the progression of breast cancer also remain largely unanswered questions

Management of the Sickle Cell Trait: An Opinion by Expert Panel Members

Abstract: The number of individuals with the sickle cell trait exceeds 300 million worldwide, making sickle cell disease one of the most common monogenetic diseases globally. Because of the high frequency of sickle cell disease, reproductive counseling is of crucial importance. In addition, unlike other carrier states, Sickle Cell Trait (SCT) seems to be a risk factor for several clinical complications, such as extreme exertional injury, chronic kidney disease, and complications during pregnancy and surgery. This expert panel believes that increasing knowledge about these clinical manifestations and their prevention and management can be a useful tool for all healthcare providers involved in this issue

Management of the Sickle Cell Trait: An Opinion by Expert Panel Members.

The number of individuals with the sickle cell trait exceeds 300 million worldwide, making sickle cell disease one of the most common monogenetic diseases globally. Because of the high frequency of sickle cell disease, reproductive counseling is of crucial importance. In addition, unlike other carrier states, Sickle Cell Trait (SCT) seems to be a risk factor for several clinical complications, such as extreme exertional injury, chronic kidney disease, and complications during pregnancy and surgery. This expert panel believes that increasing knowledge about these clinical manifestations and their prevention and management can be a useful tool for all healthcare providers involved in this issue

Pelvic trauma : WSES classification and guidelines

Complex pelvic injuries are among the most dangerous and deadly trauma related lesions. Different classification systems exist, some are based on the mechanism of injury, some on anatomic patterns and some are focusing on the resulting instability requiring operative fixation. The optimal treatment strategy, however, should keep into consideration the hemodynamic status, the anatomic impairment of pelvic ring function and the associated injuries. The management of pelvic trauma patients aims definitively to restore the homeostasis and the normal physiopathology associated to the mechanical stability of the pelvic ring. Thus the management of pelvic trauma must be multidisciplinary and should be ultimately based on the physiology of the patient and the anatomy of the injury. This paper presents the World Society of Emergency Surgery (WSES) classification of pelvic trauma and the management Guidelines.Peer reviewe