Domain-Wall Topology Induced by Spontaneous Symmetry Breaking in Polariton Graphene.

We present a numerical study of exciton-polariton (polariton) condensation in a staggered polariton graphene showing a gapped s band. The condensation occurs at the kinetically favorable negative mass extrema (K and K^{'} valleys) of the valence band. Considering attractive polariton-polariton interaction allows us to generate a spatially extended condensate. The symmetry breaking occurring during the condensate buildup leads to the formation of valley-polarized domains. This process can either be spontaneous, following the Kibble-Zurek scenario, or triggered, leading to a controlled spatial distribution of valley-polarized domains. The selection of a single valley breaks time-reversal symmetry, and the walls separating domains exhibit a reconfigurable topologically protected chiral current. This current emerges as a result of the interplay between the nontrivial valley topology and the condensation-induced symmetry breaking.

[Attitude and beliefs of healthcare workers toward influenza vaccination in Internal Medicine: A cross-sectional survey]. / Attitude et croyances du personnel soignant en Médecine Interne vis-à-vis de la vaccination antigrippale saisonnière : étude transversale descriptive.

INTRODUCTION: The rate of vaccination in HCWs in France remains low. We aimed to analyze the attitude and beliefs of HCWs toward influenza vaccination in Internal Medicine wards. METHODS: We conducted a cross-sectional survey of HCWs in the departments of Internal Medicine of two tertiary hospitals in France. An anonymous questionnaire designed for this study was used to collect demographic, health beliefs and attitudes, and medical knowledge related to the influenza and influenza vaccine. The survey started shortly prior the 2019 influenza season. RESULTS: The surveys were completed by 158 (29[18-62] years-old ; 75.9% female ; 69.6% non-medical workers) of 187 (84.5%) HCWs. Overall, influenza vaccination coverage rate was 50.6% (n=80/158). Higher vaccination coverage was found in physician and in HCWs who had a better knowledge about the virus transmission. The reason to fulfill vaccination recommendations was to protect the patients, their relatives and themselves for more than 80% of HCWs compliant to vaccination recommendation. More than a third of HCWs (n=59/158; 37.3%) refused to be vaccinated or hesitated. Among them, 12 (12/59, 20.3%) believed that influenza vaccine could cause flu. The main reasons for reluctant HCWs to eventually accept to be vaccinated were a mandatory vaccination program and the demonstration of a better vaccine efficacy to prevent the disease. CONCLUSION: Influenza vaccination coverage among HCWs in Internal Medicine remains low. Education campaigns targeting in priority nurses and nurse assistants is mandatory to improve the compliance of HCWs to vaccination recommendation.

Management and prevention of imported malaria in children. Update of the French guidelines.

Since the 2007 French guidelines on imported Falciparum malaria, the epidemiology, treatment, and prevention of malaria have changed considerably requiring guidelines for all Plasmodium species to be updated. Over the past decade, the incidence of imported malaria has decreased in all age groups, reflecting the decrease in the incidence of malaria in endemic areas. The rates of severe pediatric cases have increased as in adults, but fatalities are rare. The parasitological diagnosis requires a thick blood smear (or a rapid immunochromatographic test) and a thin blood film. Alternatively, a rapid antigen detection test can be paired with a thin blood film. Thrombocytopenia in children presenting with fever is highly predictive of malaria following travel to a malaria-endemic area and, when detected, malaria should be strongly considered. The first-line treatment of uncomplicated P. falciparum malaria is now an artemisinin-based combination therapy (ACT), either artemether-lumefantrine or artenimol-piperaquine, as recommended by the World Health Organization in endemic areas. Uncomplicated presentations of non-falciparum malaria should be treated either with chloroquine or ACT. The first-line treatment of severe malaria is now intravenous artesunate which is more effective than quinine in endemic areas. Quinine is restricted to cases where artesunate is contraindicated or unavailable. Prevention of malaria in pediatric travelers consists of nocturnal personal protection against mosquitoes (especially insecticide-treated nets) combined with chemoprophylaxis according to the risk level.

Subtle temperature increase can interact with individual size and social context in shaping phenotypic traits of a coldwater fish.

Temperature and individual egg size have been long studied in the development of fishes because of their direct effects on individual fitness. Here we studied the combined effects of three important factors for fish development, i.e. egg size, social environment and water temperature. Arctic charr (Salvelinus alpinus), a coldwater fish known to be phenotypically plastic, was used to investigate how these factors may affect growth and foraging behaviour of juvenile fish in a benign environment. We accounted for the social environment during early development by comparing fish raised in groups and in isolation. We examined the effect of egg size and a 2 °C difference on foraging behaviour, activity and growth a few weeks after first feeding. Growth trajectories of fish originating from large and small eggs were similar within each temperature: larger fish coming large eggs were at all time larger than smaller fish. There was no indication that small fish raised at a higher temperature grew faster than larger fish raised at a lower temperature. A 2 °C difference in temperature affected the behaviour of fish differently according to body size and/or social context. The foraging probability difference between fish raised in groups and fish briefly isolated was higher at 4.5 °C than at 6.5 °C for both size fish. Finally, there was no repeatability in foraging behaviour and mobility for isolated individuals. These results highlight the importance of small changes in temperature when evaluating growth and behaviour of fishes, and reveal the importance of considering the interaction of temperature with other factors, e.g. individual size and social environment, especially at early stages of development in fishes. We discuss these findings in the context of rapid changes in temperature and how temperature and its interaction with other factors may affect the phenotypes, ecology and evolution of coldwater fishes.

Development of locomotion over inclined surfaces in laying hens.

The purpose of the present study was to evaluate locomotor strategies during development in domestic chickens (Gallus gallus domesticus); we were motivated, in part, by current efforts to improve the design of housing systems for laying hens which aim to reduce injury and over-exertion. Using four strains of laying hens (Lohmann Brown, Lohmann LSL lite, Dekalb White and Hyline Brown) throughout this longitudinal study, we investigated their locomotor style and climbing capacity in relation to the degree (0 to 70°) of incline, age (2 to 36 weeks) and the surface substrate (sandpaper or wire grid). Chicks and adult fowl performed only walking behavior to climb inclines ⩽40° and performed a combination of wing-assisted incline running (WAIR) or aerial ascent on steeper inclines. Fewer birds used their wings to aid their hind limbs when climbing 50° inclines on wire grid surface compared with sandpaper. The steepness of angle achieved during WAIR and the tendency to fly instead of using WAIR increased with increasing age and experience. White-feathered strains performed more wing-associated locomotor behavior compared with brown-feathered strains. A subset of birds was never able to climb incline angles >40° even when using WAIR. Therefore, we suggest that inclines of up to 40° should be provided for hens in three-dimensional housing systems, which are easily negotiated (without wing use) by chicks and adult fowl.

The internet as a source of support for youth with chronic conditions: A qualitative study.

BACKGROUND: Adolescents living with chronic conditions often portray themselves as "healthy" online, yet use the Internet as one of their top sources of health information and social communication. There is a need to develop online support programs specific to adolescents with chronic conditions in order to provide a private space to discuss concerns. This paper endeavors to increase our understanding of the online support needs and wants of these adolescents and their interest in and preferences for an online support program. METHODS: A qualitative descriptive study using semistructured interviews was completed. Stratified purposive sampling was utilized to ensure a representative sample based on age and diagnosis. English speaking adolescents (aged 12-18 years) diagnosed with a chronic condition were recruited from clinic and inpatient areas across 3 paediatric hospitals in Canada. RESULTS: Thirty-three participants aged 15.3 ± 1.8 years (64% female) completed the study. The main topics identified were (a) the purpose of current online activity, (b) the benefits and challenges of existing online supports, and (c) a description of ideal online resources. The purpose of online activity was social networking, information, online gaming, and social support. When accessing health information online, participants prioritized websites that were easy to access and understand despite the trustworthiness of the site. The reported benefits and challenges varied across participants with many areas perceived as both a benefit and a challenge. The majority of participants were interested in participating in an online support program that included both accurate disease-related information and a community of other adolescents to provide social support. CONCLUSIONS: Adolescents with chronic conditions are interested in online support that encompasses health information and social support that is flexible and easy to navigate. Findings can be used to develop or adapt existing online support programs for adolescents with chronic conditions to help increase engagement and utilization.

Disequilibrium in the uranium and actinium series in oil scale samples.

We have investigated the disequilibrium of the uranium and actinium series and have found both 226Ra (90,200 ± 4300 Bq/kg) and 228Ra have activity concentrations orders of magnitude higher that 238U (1.83 ± 0.36 Bq/kg) and 232Th (7.0 ± 0.4) which are at the head of the decay series. As well the activity concentration of 210Pb (24,400 ± 1200 Bg/kg) was about 3.6 times less than 226Ra. Once an efficiency curve was constructed summing corrections for specific isotopes in the decay change also needed to be taken in consideration. Furthermore, self-attenuation of the photons especially the 46.5 keV belonging to 210Pb was calculated to be 78% since the scale had elevated elemental concentrations of high-Z elements such as barium and strontium.

Active pulmonary tuberculosis: Role for amikacin in early treatment.

OBJECTIVE: To evaluate the efficacy of amikacin on sputum conversion during initial sputum smear positive tuberculosis treatment. MATERIAL AND METHODS: Single-center observational cohort study (2012-2013) evaluating time to sputum smear conversion with standard treatment (ST) versus standard treatment+amikacin (IV 15mg/kg/day) for seven days (STamK). RESULTS: Forty-five patients were included. Median time to smear negative samples was 26.5 days (14-56) for the 30 (66.7%) patients included in the ST group and 48 days (19.5-69.5) for the 15 patients (33.3%) included in the STamK group (P=0.76). Time to negative culture was only known for 27 patients (61.4%): 47.5 days (26-58) for 18 patients in the ST group and 40 days (14-77) for nine patients in the STamK group. CONCLUSION: Despite our small sample size, the addition of amikacin in active tuberculosis treatment did not seem to impact time to smear conversion or period of contagiousness.

[Visceral leishmaniasis without splenomegaly. A pediatric case report]. / Leishmaniose viscérale sans splénomégalie. À propos d'un cas chez un nourrisson.

Pediatric visceral leishmaniasis is caused by Leishmania infantum, a dog parasite transmitted to humans by the bite of the female phlebotomine sand fly. The well-known clinical triad is fever, pallor, and splenomegaly. A secondary macrophage activation syndrome (MAS) can complicate this infection, which is lethal when not treated. When MAS is observed without any explanation, a visceral leishmaniasis is highly recommended. We report a case of visceral leishmaniasis in a 21-month-old child complicated by a macrophage activation syndrome without splenomegaly. No immunodeficiency was diagnosed that could explain this unusual clinical condition. To our knowledge, this is the first case of visceral leishmaniasis without splenomegaly reported to date.

The value of cough peak flow measurements in the assessment of extubation or decannulation readiness.

Insufficient cough strength has a major role in extubation and decannulation outcomes. Cough capacity can be easily evaluated by measuring flows during coughing. Values vary depending on whether cough flows are measured through the mouth or through a tracheostomy or endotracheal tube. It is important to standardize these measurements and start using them routinely in the extubation and decannulation processes. Values of cough peak flow >160 L/min measured at the mouth or a value of cough PEF >60 L/min measured at the endotracheal tube suggest successful decannulation or extubation.

Serial evaluation of neutrophil function in tumour-bearing dogs undergoing chemotherapy.

We hypothesized that neutrophil function in tumour-bearing dogs is negatively impacted by chemotherapy. Flow cytometric techniques were used to assess neutrophil oxidative burst and phagocytic activities at baseline, 7 and 21 days after induction chemotherapy in 20 dogs with lymphoma. Dogs had a lower percentage of neutrophils exhibiting oxidative burst activity after stimulation with Escherichia coli (day 7; P = 0.009) and phorbol 12-myristate 13-acetate (PMA) (days 7 and 21; P = 0.0003 and P = 0.01, respectively), compared with healthy controls. From day 0 to 7, the percentage of neutrophils exhibiting oxidative burst activity decreased after stimulation with E. coli (P = 0.016) and PMA (P = 0.0006). Induction chemotherapy suppresses the percentage of neutrophils capable of oxidative burst in dogs with lymphoma, with improvement in phagocytic activity over time (P = 0.03). The impact of neutrophil dysfunction on incidence and severity of sepsis in dogs receiving chemotherapy should be investigated.

The development of bone mineral lateralization in the arms.

UNLABELLED: Bone mineral content (BMC) is known to be greater in the dominant arm after the age of 8 years. We studied a group of children and found that BMC sidedness gradually increased up to the age of 6 years and then remained stable into late adolescence. INTRODUCTION: Bone mineral content (BMC) exhibits sidedness in the arms after the age of 8 years, but it is not known whether BMC is greater in the dominant arm from birth or whether lateralization develops in early childhood. To address this, we examined bone mineral status in relation to handedness and age. METHODS: Subjects (N = 158) were children recently initiating glucocorticoids for underlying disease (leukemia 43 %, rheumatic conditions 39 %, nephrotic syndrome 18 %). Handedness was determined by questionnaire and BMC by dual-energy X-ray absorptiometry. RESULTS: Median age was 7.2 years (range, 1.5 to 17.0 years), 49 % was male, and the spine BMD Z-score was -0.9 (SD, 1.3). By linear regression, BMC sidedness in the arms was significantly related to age (r = 0.294, p = 0.0005). Breakpoint analysis revealed two lines with a knot at 6.0 years (95 % CI, 4.5-7.5 years). The formula for the first line was: dominant:nondominant arm BMC ratio = 0.029 × age [in years] + 0.850 (r = 0.323, p = 0.017). The slope of the second line was not different from 0 (p = 0.332), while the slopes for the two lines were significantly different (p = 0.027). CONCLUSIONS: These results show that arm BMC sidedness in this patient group develops up to age 6 years and then remains stable into late adolescence. This temporal profile is consistent with mechanical stimulation of the skeleton in response to asymmetrical muscle use as handedness becomes manifest.

Interleukin-15 plays an essential role in the pathogenesis of autoimmune diabetes in the NOD mouse.

AIMS/HYPOTHESIS: IL-15, induced by innate immune stimuli, promotes rheumatoid arthritis and inflammatory bowel disease. However, its role in autoimmune type 1 diabetes is unclear. Our aim is to define the role of IL-15 in the pathogenesis of diabetes in the NOD mouse model. METHODS: We generated NOD.Il15(-/-) mice expressing a polyclonal repertoire of T cell antigen receptor (TCR) or a transgenic TCR and monitored diabetes onset and insulitis. NOD Scid.Il15(-/-) (full name NOD.CB17-Prkdc (scid)/NCrCrl) and NOD Scid.gamma (full name NOD.Cg-Prkdc(scid) Il2rg ( tm1Wjl )/SzJ) mice were used to distinguish the requirement for IL-15 signalling in CD8(+) T cells and antigen-presenting cells (APCs) to induce disease. We examined the effect of blocking IL-15 signalling on diabetes onset in NOD mice. RESULTS: At 7 months of age, more than 75% of the NOD Il15(-/-) female mice remained diabetes free compared with only 30% in the control group. Diabetes incidence was also decreased in 8.3-NOD (full name NOD Cg-Tg[TcraTcrbNY8.3]-1Pesa/DvsJ).Il15(-/-) mice expressing a highly pathogenic transgenic TCR on CD8(+) T cells. Adoptive transfer of splenocytes from diabetic NOD and 8.3-NOD donors induced disease in NOD Scid recipients but not in NOD Scid.Il15(-/-) or NOD Scid.gamma mice. Transient blockade of IL-15 signalling at the onset of insulitis prevented diabetes in NOD mice. CONCLUSIONS/INTERPRETATION: Our results show that IL-15 is needed for the initial activation of diabetogenic CD8(+) T cells as well as for sustaining the diabetogenic potential of antigen-stimulated cells, acting on both CD8(+) T cells and on APCs. Our findings demonstrate a critical role for IL-15 in the pathogenesis of autoimmune diabetes and suggest that IL-15 is a promising therapeutic target.

Permeation properties of the hair cell mechanotransducer channel provide insight into its molecular structure.

Mechanoelectric transducer (MET) channels, located near stereocilia tips, are opened by deflecting the hair bundle of sensory hair cells. Defects in this process result in deafness. Despite this critical function, the molecular identity of MET channels remains a mystery. Inherent channel properties, particularly those associated with permeation, provide the backbone for the molecular identification of ion channels. Here, a novel channel rectification mechanism is identified, resulting in a reduced pore size at positive potentials. The apparent difference in pore dimensions results from Ca(2+) binding within the pore, occluding permeation. Driving force for permeation at hyperpolarized potentials is increased because Ca(2+) can more easily be removed from binding within the pore due to the presence of an electronegative external vestibule that dehydrates and concentrates permeating ions. Alterations in Ca(2+) binding may underlie tonotopic and Ca(2+)-dependent variations in channel conductance. This Ca(2+)-dependent rectification provides targets for identifying the molecular components of the MET channel.

Radiotherapy-induced myelosuppression in dogs: 103 cases (2002-2006).

Definitive radiotherapy refers to delivery of large doses, typically 48-62 Gray, of ionizing radiation over several weeks using a daily or alternate-day fractionation schedule. The impact of definitive radiotherapy alone on haematopoiesis in tumour-bearing dogs is unknown. Medical records from 103 dogs receiving definitive (60) Cobalt teletherapy for cancer over a 5-year period were reviewed for signalment, tumour type and location, total radiotherapy dose and fractionation scheme. Complete blood count data were collected before, halfway through, and at the end of radiation treatment, and analysed for changes associated with patient variables. The results demonstrate significant reductions in haematocrit, total white blood cell count, neutrophils, eosinophils, monocytes, lymphocytes and platelets occurred during definitive radiotherapy but remained within laboratory reference intervals. These data are important for anticipation of toxicity associated with combinations of radiotherapy and chemotherapy in dogs but do not support the routine monitoring of haematology parameters during definitive radiotherapy.

Leukocyte and platelet changes following low-dose lipopolysaccharide administration in five dogs.

Effects of low-dose LPS (0.1 µg/kg i.v.) on leukocyte and platelet parameters measured using an Advia 120 hematology analyzer were investigated. Five dogs received a saline sham treatment prior to LPS, and blood was collected before and 3, 6, and 24 h post-treatment. LPS-treated dogs had mild neutrophil toxic change and increased neutrophil bands at 3 and 6 h. Compared to saline-treated controls, total leukocyte, neutrophil, and monocyte counts of LPS-treated dogs were significantly decreased at 3 h and increased at 24 h. Compared to baseline, total leukocyte counts of LPS-treated dogs were significantly decreased at 3 h and increased at 24 h. Mean platelet volume was significantly increased and mean platelet component concentration was decreased at 3 h compared to baseline. Platelet count was significantly decreased at 3 and 6 h; plateletcrit did not change significantly. High dosage is not required in order to detect LPS-mediated hematologic effects in dogs. Low-dose LPS administration causes significant changes in leukocyte and platelet indices in dogs without causing severe clinical signs or death.

Prevalent vertebral fractures among children initiating glucocorticoid therapy for the treatment of rheumatic disorders.

OBJECTIVE: Vertebral fractures are an under-recognized problem in children with inflammatory disorders. We studied spine health among 134 children (87 girls) with rheumatic conditions (median age 10 years) within 30 days of initiating glucocorticoid therapy. METHODS: Children were categorized as follows: juvenile dermatomyositis (n = 30), juvenile idiopathic arthritis (n = 28), systemic lupus erythematosus and related conditions (n = 26), systemic arthritis (n = 22), systemic vasculitis (n = 16), and other conditions (n = 12). Thoracolumbar spine radiograph and dual x-ray absorptiometry for lumbar spine (L-spine) areal bone mineral density (BMD) were performed within 30 days of glucocorticoid initiation. Genant semiquantitative grading was used for vertebral morphometry. Second metacarpal morphometry was carried out on a hand radiograph. Clinical factors including disease and physical activity, calcium and vitamin D intake, cumulative glucocorticoid dose, underlying diagnosis, L-spine BMD Z score, and back pain were analyzed for association with vertebral fracture. RESULTS: Thirteen vertebral fractures were noted in 9 children (7%). Of these, 6 patients had a single vertebral fracture and 3 had 2-3 fractures. Fractures were clustered in the mid-thoracic region (69%). Three vertebral fractures (23%) were moderate (grade 2); the others were mild (grade 1). For the entire cohort, mean +/- SD L-spine BMD Z score was significantly different from zero (-0.55 +/- 1.2, P < 0.001) despite a mean height Z score that was similar to the healthy average (0.02 +/- 1.0, P = 0.825). Back pain was highly associated with increased odds for fracture (odds ratio 10.6 [95% confidence interval 2.1-53.8], P = 0.004). CONCLUSION: In pediatric rheumatic conditions, vertebral fractures can be present prior to prolonged glucocorticoid exposure.