bluuebunny/crossref_metadata_2025 huggingface dataset:
Ageing adversely affects the migration and function of marginal zone B cells
Authors: Turner Vivian M. , Mabbott Neil A.
Published: April 2017

Marginal zone (MZ) B cells are positioned within the spleen to capture blood‐borne antigen and immune complexes and deliver them to follicular dendritic cells in the B‐cell follicles. We show that within the spleens of aged mice antigen capture by MZ B cells, and their ability to shuttle between the follicle and MZ, were impaired. The ability of aged MZ B cells to migrate towards the MZ chemoattractant sphingosine‐1‐phosphate was increased, suggesting that aged MZ B cells had a greater propensity to be retained within the MZ. An extrinsic impairment in aged B‐cell migration towards the MZ was demonstrated using bone marrow chimeras. The follicular shuttling of MZ B cells derived from either young or aged bone marrow was similarly reduced in aged recipient spleens, showing that ageing effects on splenic stromal cells were responsible for the impaired follicular shuttling of MZ B cells. MZ B cells rapidly mount T‐cell‐independent (TI) antibody‐responses to microbial polysaccharide antigen. In aged mice the ability to produce immunoglobulins in response to the TI type 1 antigen TNP‐LPS was impaired. These ageing‐related changes to the MZ and MZ B cells have implications for the clearance of blood‐borne pathogens. Indeed elderly people have increased susceptibility to Streptococcus pneumoniae, a TI antigen, and decreased responses to vaccination. A thorough analysis of the mechanisms that underpin the ageing‐related decline in the status of the MZ and MZ B cells will help the design of novel treatments to improve immunity in the elderly.
Phenotypic characterization of regulatory T cells from antiretroviral‐naive HIV‐1‐infected people
Authors: Ambada Georgia N. , Ntsama Claudine E. , Nji Nadesh N. , Ngu Loveline N. , Sake Carole N. , Lissom Abel , Tchouangeu Flaurent T. , Tchadji Jules , Sosso Martin , Etoa François‐Xavier , Nchinda Godwin W.
Published: April 2017

Regulatory T (Treg) cells play a key role in dampening excessive immune activation. However, antiretroviral therapy (ART) ‐naive HIV‐1 infection maintains the immune system in a sustained state of activation that could alter both Treg cell surface markers and functions. As Treg cell surface markers are directly linked to their functions the overall objective of this study was to determine how ART‐naive HIV infection affects the phenotypic properties of Treg cells. Our data showed that in ART‐naive HIV‐1 infection, Treg cells are dominated by effector (CD45RA+ CD27− CCR7− CD62L−) and effector memory (CD45RA− CD27− CCR7− CD62L−) cells. In contrast Treg cells from HIV‐negative individuals were mainly naive (CD45RA+ CD27+ CCR7+ CD62L+) and central memory (CD45RA− CD27+ CCR7+ CD62L+) cells. Whereas effector and effector memory Treg cells showed enhanced expression of CD39 (P < 0·05), CD73 (P < 0·001), HLA‐DR and CD38 (P < 0·001); naive and central memory Treg cells showed a significant reduction in the expression of these markers. Overall Treg cell frequencies within total CD4+ T cells correlated positively with plasmatic HIV‐1 viral load. As increased viral load is associated with augmented CD4+ T‐cell destruction; this could suggest a resistance of peripheral Treg cells to HIV‐1 destruction. Hence the modulation of Treg cell phenotype and frequencies could be considered in designing immunotherapeutic strategies targeting immune system restoration during HIV‐1 infection.
CD8 T‐cell regulation by T regulatory cells and the programmed cell death protein 1 pathway
Authors: Penaloza‐MacMaster Pablo
Published: April 2017

The primary function of the immune system is to protect the host from infectious microorganisms and cancers. However, a major component of the immune response involves the direct elimination of cells in the body and the induction of systemic inflammation, which may result in life‐threatening immunopathology. Therefore, the immune system has developed complex mechanisms to regulate itself with a specialized subset of CD4 T lymphocytes (referred to as regulatory T cells) and immune checkpoint pathways, such as the programmed cell death protein 1 pathway. These immune regulatory mechanisms can be exploited by pathogens and tumours to establish persistence in the host, warranting a deeper understanding of how to fine‐tune immune responses during these chronic diseases. Here, I discuss various features of immune regulatory pathways and what important aspects must be considered in the next generation of therapies to reverse immune exhaustion, understanding that this process is a natural mechanism to prevent the host from destroying itself.
Inflammatory responses to influenza vaccination at the extremes of age
Authors: McDonald Jacqueline U. , Zhong Ziyun , Groves Helen T. , Tregoning John S.
Published: April 2017

Age affects the immune response to vaccination, with individuals at the extremes of age responding poorly. The initial inflammatory response to antigenic materials shapes the subsequent adaptive response and so understanding is required about the effect of age on the profile of acute inflammatory mediators. In this study we measured the local and systemic inflammatory response after influenza vaccination or infection in neonatal, young adult and aged mice. Mice were immunized intramuscularly with inactivated influenza vaccine with and without the adjuvant MF59 and then challenged with H1N1 influenza. Age was the major factor affecting the inflammatory profile after vaccination: neonatal mice had more interleukin‐1α (IL‐1α), C‐reactive protein (CRP) and granulocyte–macrophage colony‐stimulating factor (GMCSF), young adults more tumour necrosis factor‐α (TNF), and elderly mice more interleukin‐1 receptor antagonist (IL‐1RA), IL‐2RA and interferon‐γ‐induced protein 10 (IP10). Notably the addition of MF59 induced IL‐5, granulocyte colony‐stimulating factor (G‐CSF), Keratinocyte Chemotractant (KC) and monocyte chemoattractant protein 1 (MCP1) in all ages of animals and levels of these cytokines correlated with antibody responses. Age also had an impact on the efficacy of vaccination: neonatal and young adult mice were protected against challenge, but aged mice were not. There were striking differences in the localization of the cytokine response depending on the route of exposure: vaccination led to a high serum response whereas intranasal infection led to a low serum response but a high lung response. In conclusion, we demonstrate that age affects the inflammatory response to both influenza vaccination and infection. These age‐induced differences need to be considered when developing vaccination strategies for different age groups.
Sample Size, Statistical Power, and False Conclusions in Infant Looking‐Time Research
Authors: Oakes Lisa M.
Published: April 2017

Infant research is hard. It is difficult, expensive, and time‐consuming to identify, recruit, and test infants. As a result, ours is a field of small sample sizes. Many studies using infant looking time as a measure have samples of 8–12 infants per cell, and studies with more than 24 infants per cell are uncommon. This paper examines the effect of such sample sizes on statistical power and the conclusions drawn from infant looking‐time research. An examination of the state of the current literature suggests that most published looking‐time studies have low power, which leads in the long run to an increase in both false positive and false negative results. Three data sets with relatively large samples (>30 infants) were used to simulate experiments with smaller sample sizes; 1,000 random subsamples of 8, 12, 16, 20, and 24 infants from the overall samples were selected, making it possible to examine the systematic effect of sample size on the results. This approach revealed that despite clear results with the original large samples, the results with smaller subsamples were highly variable, yielding both false positive and false negative outcomes. Finally, a number of emerging possible solutions are discussed.
Estimates of influenza and respiratory syncytial virus incidences with fraction modeling approach in Baguio City, the Philippines, 2012‐2014
Authors: Kamigaki Taro , Aldey Portia P. , Mercado Edelwisa S. , Tan Alvin G. , Javier Jenaline B. , Lupisan Socorro P. , Oshitani Hitoshi , Tallo Veronica L.
Published: April 2017

Background

Estimation of the incidences of influenza and respiratory syncytial virus (RSV) infection is important for disease control. Previous estimate in the city showed a substantial burden of influenza in both outpatients and inpatients while it did not account for individuals who do not seek medical attention nor RSV.

Patients/Methods

A total of 17 674 influenza‐like illness (ILI) and 13 242 severe acute respiratory illness (SARI) cases were recruited, and samples were collected from 6267 and 2962 of ILI and SARI cases, respectively. RT‐PCR assays were performed to detect influenza and RSV in the samples. A health‐seeking behavior survey was conducted from February 2014 to April 2014 to estimate the fraction of infected individuals who did not seek medical attention between rainy and dry season.

Results

Average influenza and RSV incidence rates in outpatients were 1.6 and 1.4 per 1000 individuals, respectively, and the highest incidence rate for both viruses was found in the of 6‐23 month age group. Average influenza and RSV hospitalization incidence rates were 1.7 and 1.9 per 1000 individuals, respectively. Further, we estimated that the incidence rates of influenza and RSV in individuals who did not seek medical attention were threefold and 1.6‐fold those in the medically attended population.

Conclusions

Respiratory syncytial virus and influenza pose a substantial disease burden, particularly in hospitalized cases. The implementation of either a community‐based approach or an enhanced surveillance system in combination with a community survey will allow a better understanding of the disease burdens of RSV and influenza in the Philippines.
Influence of time to diagnosis of severe influenza on antibiotic use, length of stay, isolation precautions, and mortality: a retrospective study
Authors: Akers Isabel E. , Weber Rainer , Sax Hugo , Böni Jürg , Trkola Alexandra , Kuster Stefan P.
Published: April 2017

Background

Timely diagnosis of influenza infection in patients might help reduce antibiotic use during influenza seasons and, consequently, antibiotic selection pressure. In this retrospective cohort study, we aimed to evaluate whether time to influenza diagnosis in patients with severe influenza is associated with the duration of antibiotic therapy.

Methods

We retrospectively included all hospitalized patients >16 years who tested positive for influenza A or B by polymerase chain reaction during influenza seasons 2013/2014 or 2014/2015 at the University Hospital Zurich. The primary aim was to assess the association between timing of laboratory‐confirmed influenza diagnosis and duration of antibiotic therapy. Secondary outcomes were length of hospital stay, duration of isolation precautions, and mortality. Early diagnosis was defined as laboratory confirmation on the day of or the day after hospital admission or symptom onset.

Results

A total of 126 patients were included (median age 57 years). Timing of influenza diagnosis was not associated with the duration of antibiotic treatment, the duration of isolation precautions, or mortality. Early influenza was associated with reduced length of hospital stay (median 7 vs 9 days [P=.014]) in patients with community‐acquired influenza.

Conclusions

Although the duration of antibiotic therapy and mortality were found unaffected by early influenza diagnosis, our data indicate that it is linked with a reduction in the length of hospitalization in patients with community‐acquired influenza. This highlights a need to also fully understand the effect of time to diagnosis of bacterial pathogens on antibiotic prescribing patterns in order to exploit the potential of early influenza diagnosis in patient care.
“Hans was a Storyteller; He Turned Statistics into a Performing Art”
Authors: Tarran Brian
Published: April 2017

Remembering Hans Rosling, who died 7 February aged 68
Investigation of optical properties: Eu with Al codoping in aluminum silicate glasses and glass‐ceramics
Authors: Gao Yuan , Qiu Jianbei , Zhou Dacheng
Published: April 2017

Eu‐doped transparent oxyfluoride aluminosilicate glass was prepared by controlling with Al codoping of melt‐quenched glass fabricated under air atmosphere. In the presence of Al input, the photoluminescence emission spectra under 393 nm excitation shows a blue shift by adjusting the ratio of Eu3+ and Eu2+. After heat treatment of glass, the ratio of Eu3+ and Eu2+ of luminescence emission were changed by controlling treatment temperature. The PL intensity of Eu3+ and Eu2+ ions in the glass‐ceramics (GC) was much stronger than in the precursor glass (PG). The possible mechanism responsible for color tuneability of the ratio of Eu3+ and Eu2+ doped was discussed.
The influence of composition and temperature on hydrated phase assemblages in magnesium oxychloride cements
Authors: Liu Zhuangzhuang , Balonis Magdalena , Huang Jian , Sha Aimin , Sant Gaurav
Published: April 2017

Due to their nonhydraulic nature, magnesium oxychloride cements (MOCs) are susceptible to degradation following contact with water. Improving the water resistance of these materials requires better understanding of hydrated phase relations and the sensitivity of hydrated phases to water. Toward this end, a series of targeted experiments and complementary thermodynamic calculations were carried out to assess hydrated phase assemblages in the system MgO‐MgCl2‐H2O across a range of compositions. Focus is placed on appraising the effects of composition and reaction temperature. In broad agreement with literature data, under ambient conditions, hydrated MOCs are noted to contain Phase 3 (P3), Phase 5 (P5), and brucite, but the mass partitioning of these phases is highly dependent on H2O/MgCl2 and MgO/MgCl2 molar ratio as well as curing temperature and age. At room temperature, P3 is favored at lower water contents, however, P5 and/or brucite are favored to form as water availability increases. Thermodynamic calculations indicate that P3 is “more stable” than P5 at lower temperatures—an outcome which impacts the engineering properties, for example, strength and volume stability. The impacts of the accuracy and self‐consistency of currently available thermodynamic data and their implications on predicted phase assemblages are discussed.
Abnormal reoxidation effects in Ba‐excess La‐doped BaTiO3 ceramics prepared by the reduction‐reoxidation method
Authors: Zu Hao , Chen Tao , Gao Chao , Fu Qiuyun , Zhou Dongxiang , Hu Yunxiang , Zheng Zhiping , Luo Wei
Published: April 2017

Ba‐excess La‐doped BaTiO3 ceramics have been successfully applied to prepare laminated chip thermistor. Ceramics were firstly fired in a high‐purity N2 flow and then reoxidized in air to obtain positive temperature coefficient of resistivity effect. However, an abnormal reduction trend of room‐temperature (RT) resistivity was found to be always beginning at ~800°C during reoxidation. This anomaly was found closely correlated with the insulating second phase (Ba2TiO4) at grain boundary, which destroyed conducting pathways between semiconducting BaTiO3 grains. When reoxidation temperature was up to ~800°C, the insulating Ba2TiO4 could be gradually consumed and then conducting pathways reestablished leading to RT resistivity reduction. To further prove the proposed explanation, the reoxidation effects of TiO2‐added ceramics were also studied, in which no Ba2TiO4 existed and certainly the abnormal RT resistivity reduction disappeared.
Synthesis of TaB2 powders by borothermal reduction
Authors: Guo Wei‐Ming , Zeng Ling‐Yong , Su Guo‐Kang , Li Hao , Lin Hua‐Tay , Wu Shang‐Hua
Published: April 2017

Borothermal reduction processes of Ta2O5 with boron under vacuum were investigated. Ta2O5 reacted with boron to form various borides (TaB2, Ta3B4, and TaB), depending on the boron/Ta2O5 molar ratio and temperature. In order to prepare pure TaB2 powders, two routes were developed. The first route was one‐step heat treatment at 1550°C. With boron/Ta2O5 molar ratio of 9.0, pure TaB2 powders with strong agglomeration were synthesized by the first route, and the particle size and oxygen content were 0.7 μm and 0.9 wt%, respectively. The second route consisted of two‐step heat treatment at 800°C and 1550°C plus intermediate water washing. With lower boron/Ta2O5 molar ratio of 8.2, pure TaB2 powders with less agglomeration and more uniform distribution were synthesized by the second route, and the particle size and oxygen content were 0.8 μm and 0.8 wt%, respectively. Moreover, the particle size similarity of TaB2 powders by the two routes suggested that byproduct boron oxides, which were previously reported as the most important factor in promoting the coarsening of ZrB2 powders by borothermal reduction, did not lead to the significant coarsening of TaB2 powders.
CuO‐added KNbO3‐BaZrO3 lead‐free piezoelectric ceramics with low loss and large electric field‐induced strain
Authors: Park Jongseong , Kim Dae‐Hyeon , Lee Tae‐Gon , Cho Sung‐Hoon , Park Su‐Jin , Ryu Jungho , Nahm Sahn
Published: April 2017

CuO‐added (1‐x)KNbO3‐x mol%BaZrO3 ceramics with 0.0≤x≤7.0 were sintered at 960°C. Large double polarization vs electric field (P‐E) and sprout‐shaped strain vs electric field (S‐E) hysteresis curves were obtained from the specimens with x≤2.0. They exhibited large polarizing electric fields (EP) owing to the presence of a large number of defect dipoles (PDs) that formed between Cu2+ ions and oxygen vacancies. Small double P‐E hysteresis curves were observed for the specimens with x≥3.0 with reduced EP because of the decreased number of PDs and the presence of a polymorphic phase structure containing both orthorhombic and pseudocubic structures. In particular, the specimen with x=5.0 exhibited a large strain of 0.16% at 8.0 kV/mm with a small EP of 1.2 kV/mm and good fatigue property: this specimen maintained a strain of 0.13% at 6.0 kV/mm after 106 cycles of 3.0 kV/mm.
Oxygen permeation mechanism in polycrystalline mullite at high temperatures
Authors: Kitaoka Satoshi , Matsudaira Tsuneaki , Yokoe Daisuke , Kato Takeharu , Takata Masasuke
Published: April 2017

The oxygen permeability of polycrystalline mullite wafers, serving as a model environmental barrier coating layer on SiC fiber‐reinforced SiC matrix composites, was evaluated at temperatures above 1673 h with an oxygen tracer gas (18O2). Oxygen permeation occurred by grain‐boundary (GB) diffusion of oxygen from the high oxygen partial pressure (high‐Po2) surface to the low‐Po2 surface, with simultaneous GB diffusion of aluminum in the opposite direction. This GB interdiffusion of both oxygen and aluminum proceeded without acceleration or retardation, maintaining the Gibbs‐Duhem relationship. Oxygen permeation related to the GB diffusion of silicon was negligibly small compared to that generated by aluminum GB diffusion, resulting in decomposition of the mullite near the low‐Po2 surface. The GB diffusion coefficients for oxygen in the vicinity of the high‐Po2 surface were determined directly from the SIMS‐18O line profiles along individual GBs, as assessed from cross sections of the exposed wafer. The coefficients thus obtained were comparable to those determined in the absence of an oxygen potential gradient and those calculated from an oxygen permeation trial under the assumption of nearly ionic conductivity.
Low energy ion‐solid interactions and chemistry effects in a series of pyrochlores
Authors: Dong Liyuan , Li Yuhong , Devanathan Ram , Setyawan Wahyu , Gao Fei
Published: April 2017

The effect of chemistry on low energy recoil events was investigated at 10 K for each type of atom in pyrochlores, using molecular dynamics simulation. Contour plots of the threshold displacement energy (Ed) in Gd2Zr2O7 have been produced along more than 80 directions for each individual species. The Ed surface for each type of atom in Gd2Zr2O7 is highly anisotropic; Ed of Zr exhibits the largest degree of anisotropy, while that of O8b exhibits the smallest. The recommended values of Ed in Gd2Zr2O7 based on the observed minima are 56, 94 and 25 eV, respectively, for Gd, Zr, and O. The influence of cation radius on Ed in pyrochlores A2B2O7 (with A‐site ranging from Lu3+ to La3+ and B‐site ranging from Ti4+ to Ce4+) was also investigated along three directions [100], [110], and [111]. The Ed in pyrochlores strongly depended on the atom type, atom mass, knock‐on direction, and lattice position. The defects produced after low energy displacement events included cation antisite defects, cation Frenkel pairs, anion Frenkel pairs, various vacancies, and interstitials. Ce doping in pyrochlores may affect the radiation response, because it resulted in drastic changes in cation and anion displacement energies and formation of an unusual type of anti‐site defect. This work demonstrates links between Ed and amorphization resistance.
Preparation, luminescence properties and energy transfer of Ca9Y(PO4)7: Eu2+‐Tb3+ phosphors
Authors: Tang Miao , Fan Yanting , Qiu Zhongxian , Zhang Jilin , Yu Liping , Li Chengzhi , Lian Shixun , Zhou Wenli
Published: April 2017

Tb3+‐doped and Eu2+, Tb3+ co‐doped Ca9Y(PO4)7 phosphors were synthesized by conventional solid‐state method. Additionally, the luminescence properties, decay behavior and energy transfer mechanism have already been investigated in detail. The green emission intensity of Tb3+ ions under NUV excitation is weak due to its spin‐forbidden f‐f transition. While Eu2+ can efficiently absorb NUV light and yield broad blue emission, most of which can be absorbed by Tb3+ ions. Thus, the emission color can be easily tuned from cyan to green through the energy transfer of Eu2+→Tb3+ in Ca9Y(PO4)7:Eu2+,Tb3+ phosphor. In this work, the phenomenon of cross‐relaxation between 5D3 and 5D4 are also mentioned. The energy transfer is confirmed to be resulted from a quadrupole‐quadrupole mechanism.
First‐principles investigation of chemical stability and proton conductivity of M‐doped BaZrO3 (M=K, Rb, and Cs)
Authors: Kang Sung Gu , Sholl David S.
Published: April 2017

First‐principles calculations were carried out to examine the chemical stability and proton conductivity of A‐site‐doped BaZrO3. In a previous study, we investigated these two properties of B‐site‐doped BaZrO3. [RSC Adv. 3 [10] 3333‐3341 (2013)] Here, we investigated BaZrO3 doped with K, Rb, and Cs at A‐sites. We found that K‐doped BaZrO3 showed the highest proton conductivity and chemical stability among the examined A‐site dopants with respect to the carbonate formation reaction. Remarkably, there is a lack of a trade‐off relationship between chemical stability and proton conductivity in A‐site‐doped BaZrO3.
Crystallization of calcium silicate hydrates on the surface of nanomaterials
Authors: Li Hui , Du Tao , Xiao Huigang , Zhang Qiangqiang
Published: April 2017

The poorly crystalline calcium silicate hydrate (C‐S‐H) is the primary binding phase in portland cement concrete. In this paper, the influence of adding anatase phase nano‐TiO2, nano‐SiO2, graphene oxide (GO), and multiwalled carbon nanotubes (CNT) on the crystallization and morphology of C‐S‐H are systematically investigated through tests. C‐S‐H gels were prepared using the double decomposition method, and the nanomaterial additions of nano‐TiO2, nano‐SiO2, GO, and CNT were 2 wt%, 2 wt%, 0.5 wt%, and 0.5 wt%, respectively. X‐ray diffraction (XRD) results show that a more crystalline nanostructure of C‐S‐H is induced by the addition of nano‐TiO2 or GO. This phenomenon is further confirmed by the transmission electron microscopy (TEM) observations. The TEM observations demonstrate that C‐S‐H would grow on the crystal face of TiO2 to form nanocrystalline regions with a lattice fringe spacing of 3.0 Å. When incorporated with GO, it will form a square lattice structure with a lattice constant of 3.1 Å on the surface of GO and later change to the lattice fringe structure with a spacing of 3.1 Å on the region bit away the GO surface. However, when adding nano‐SiO2 or CNT, these nanocrystalline regions are not observed. Further characterization through scanning electron microscopy (SEM) and atomic force microscopy (AFM) has been performed to investigate the effect of nanomaterials on C‐S‐H morphology. Different nanomaterials take a different morphology of C‐S‐H: sheet‐shape structures for pure C‐S‐H, rod‐shape with for C‐S‐H with nano‐TiO2, and granular agglomeration for C‐S‐H with nano‐SiO2. C‐S‐H with GO or CNT forms a structure of C‐S‐H growing on the templates.
Niobium and divalent‐modified titanium dioxide ceramics: Colossal permittivity and composition design
Authors: Li Zhenwei , Luo Xuan , Wu Wenjuan , Wu Jiagang
Published: April 2017

Colossal permittivity (CP) (εr=104~105) is attained in (A1/3Nb2/3)xTi1‐xO2 (A=Ba2+, Ca2+, Zn2+, Mg2+) ceramics. Here, (Ca1/3Nb2/3)xTi1‐xO2 material was studied as a typical example, and effects of Ca and Nb on their microstructure, dielectric properties and stability were studied. Both backscattering and elements mapping strongly confirmed the formation of secondary phases due to the addition of Ca and/or Nb. Secondary phases‐induced by Ca cannot affect dielectric properties of the ceramics when low Ca and Nb contents were doped, while secondary phases formed by Ca and Nb strongly affected their dielectric properties in a high doping level. In particular, their dielectric properties can be well modified by the optimization of sintering temperatures. In addition, the (Ca1/3Nb2/3)xTi1‐xO2 ceramics with x=0.01 exhibited the optimum dielectric properties (εr=130500 and tan δ=0.19). Electron‐pinned defect‐dipoles may be suitable to explain CP phenomenon of this work. We believed that this profound investigation can benefit the development of new TiO2 ceramics as a CP material.
Effects of phase transition on discharge properties of PLZST antiferroelectric ceramics
Authors: Xu Ran , Tian Jingjing , Zhu Qingshan , Zhao Tian , Feng Yujun , Wei Xiaoyong , Xu Zhuo
Published: April 2017

The effects of electric field‐induced phase transition on discharge properties of Pb0.94La0.04[(Zr0.52Sn0.48)0.84Ti0.16]O3 antiferroelectric (AFE) ceramics were investigated. Due to the forward phase transition, high polarization and energy density are achieved. The backward phase transition results in nonlinear increase of current in underdamped circuit. The stored charge (14.2 μC under 40 kV/cm at 22°C) can be released completely in very short duration due to the low remanent polarization. With increasing temperature, the polarization and releasable energy decline. However, the current amplitude reaches maximum at 40°C, which is attributed to the backward phase transition. The maximum current and power density are as high as 143.8 A/cm2 and 2.4 MW/cm3, which indicates the potential of the ceramics for pulsed capacitors.
Challenges in building interpersonal care in organized hospital stroke units: The perspectives of stroke survivors, family caregivers and the multidisciplinary team
Authors: Ryan Tony , Harrison Madeleine , Gardiner Clare , Jones Amanda
Published: April 2017

Aims

To explore the organized stroke unit experience from the multiple perspectives of stroke survivor, family carer and the multi‐disciplinary team.

Background

Organized stroke unit care reduces morbidity, mortality and institutionalization and is promoted globally as the most effective form of acute and postacute provision. Little research has focused on how care is experienced in this setting from the perspectives of those who receive and provide care.

Design

This study used a qualitative approach, employing Framework Analysis. This methodology allows for a flexible approach to data collection and a comprehensive and systematic method of analysis.

Method

Semi‐structured interviews were undertaken during 2011 and 2012 with former stroke unit stroke survivors, family carers and senior stroke physicians. In addition, eight focus groups were conducted with members of the multi‐disciplinary team.

Results

One hundred and twenty‐five participants were recruited. Three key themes were identified across all data sets. First, two important processes are described: responses to the impact of stroke and seeking information and stroke‐specific knowledge. These are underpinned by a third theme: the challenge in building relationships in organized stroke unit care.

Conclusions

Stroke unit care provides satisfaction for stroke survivors, particularly in relation to highly specialized medical and nursing care and therapy. It is proposed that moves towards organized stroke unit care, particularly with the emphasis on reduction of length of stay and a focus on hyper‐acute models, have implications for interpersonal care practices and the sharing of stroke‐specific knowledge.
Physical and psychological health of family carers co‐residing with an adult relative with an intellectual disability
Authors: Grey Jillian M. , Totsika Vasiliki , Hastings Richard P.
Published: April 2017

Background

Providing long‐term care to an adult relative with intellectual disability can impact negatively on caregivers’ health and well‐being.

Methods

Data were collected via online and postal questionnaires on 110 family carers’ physical and psychological health, family stress and perceived positive gains from caring. Psychological adaptation and carers’ satisfaction with available support were also examined.

Results

Study participants reported more health problems than general populations. Higher support needs of care recipients were associated with increased family stress. Carers being female were associated with lower family stress. Older age and better socio‐economic position were associated with better psychological outcomes. Other associations were consistent with psychological adaption and perceived helpfulness of support buffering negative outcomes and facilitating positive gains from caring.

Conclusions

Family carers of adults with intellectual disability appear to experience poorer health outcome than population norms. Adaption to the caregiving role may buffer negative outcomes. Further large scale, population‐based, longitudinal research is needed.
Individuality in northern lapwing migration and its link to timing of breeding
Authors: Eichhorn Götz , Bil Willem , Fox James W.
Published: April 2017

We tracked eight adult northern lapwings Vanellus vanellus (six females and two males) from a Dutch breeding colony by light‐level geolocation year‐round, three of them for multiple years. We show that birds breeding virtually next to each other may choose widely separated wintering grounds, stretching from nearby the colony west towards the UK and Ireland, and southwest through France into Iberia and Morocco. However, individual lapwings appeared relatively faithful to a chosen wintering area, and timing of outward and homeward migration can be highly consistent between years. Movements of migratory individuals were usually direct and fast, with some birds covering distances of approximately 2000 km within 2 to 4 days of travel. The two males wintered closest and returned earliest to the breeding colony. The female lapwings returned well before the onset of breeding, spending a pre‐laying period of 19 to 54 days in the wider breeding area. Despite the potential for high migration speeds, the duration that birds were absent from the breeding area increased with distance to wintering areas, a pattern which was mainly driven by an earlier outward migration of birds heading for more distant wintering grounds. Moreover, females that overwintered closer to colony bred earlier. A large variation in migration strategies found even within a single breeding colony has likely supported the species’ responsiveness to recent climate change as evidenced by a shortened migration distance and an advanced timing of reproduction in Dutch lapwings since the middle of the 20th century.
Exploring fire adaptation in a land with little fire: serotiny in Leptospermum scoparium (Myrtaceae)
Authors: Battersby Paul F. , Wilmshurst Janet M. , Curran Timothy J. , McGlone Matthew S. , Perry George L. W.
Published: April 2017

Aim

Immigrant floras often have distinctive traits, well suited to the host region but absent from the autochthonous flora. An example is serotiny in the New Zealand (NZ) small tree, Leptospermum scoparium (Myrtaceae) belonging to a strongly fire‐adapted Australian clade. Serotiny in L. scoparium has been attributed either to strong selection by fire since human settlement, or taken as evidence that pre‐human fire in NZ was more important than assumed. By integrating field data, experimental analyses and long‐term fire histories, we sought to explain the spatial pattern of serotiny in L. scoparium in NZ, and evaluate these two explanations.

Location

New Zealand.

Methods

We quantified the distribution of serotiny in L. scoparium by analysing 137 populations distributed across NZ (two previous studies and ours), including 31 with Holocene fire histories. We assessed the relationship of serotiny with a suite of fire and climate environmental predictors, and between serotiny and shoot‐level flammability.

Results

Serotiny was strongly positively associated with latitude (more in the north), lower rainfall and higher temperatures. Serotinous populations were rare at sites with no history of fire. Serotiny was most prevalent in northern wetlands, where fire was recurrent during the Holocene, but was nearly absent from the southwestern Southern Alps. Shoot‐level flammability and serotiny were not correlated.

Main conclusions

The distribution of serotiny in L. scoparium relates not only to current environments but also to the legacy of regional shifts in vegetation during Quaternary glacial–interglacial cycles. Serotiny was maintained where the landscape experienced sporadic fire, but it is absent from NZ's southern South Island because the sparse, open vegetation during the glacials did not support fire. Serotinous L. scoparium populations were therefore more common in the northern North Island. Human transformation of the fire regime over the last 750 years has likely favoured the spread of serotinous populations.
Relationship among LRP1 expression, Pyk2 phosphorylation and MMP‐9 activation in left ventricular remodelling after myocardial infarction
Authors: Revuelta‐López Elena , Soler‐Botija Carol , Nasarre Laura , Benitez‐Amaro Aleyda , de Gonzalo‐Calvo David , Bayes‐Genis Antoni , Llorente‐Cortés Vicenta
Published: April 2017

Left ventricular (LV) remodelling after myocardial infarction (MI) is a crucial determinant of the clinical course of heart failure. Matrix metalloproteinase (MMP) activation is strongly associated with LV remodelling after MI. Elucidation of plasma membrane receptors related to the activation of specific MMPs is fundamental for treating adverse cardiac remodelling after MI. The aim of current investigation was to explore the potential association between the low‐density lipoprotein receptor‐related protein 1 (LRP1) and MMP‐9 and MMP‐2 spatiotemporal expression after MI. Real‐time PCR and Western blot analyses showed that LRP1 mRNA and protein expression levels, respectively, were significantly increased in peri‐infarct and infarct zones at 10 and 21 days after MI. Confocal microscopy demonstrated high colocalization between LRP1 and the fibroblast marker vimentin, indicating that LRP1 is mostly expressed by cardiac fibroblasts in peri‐infarct and infarct areas. LRP1 also colocalized with proline‐rich tyrosine kinase 2 (pPyk2) and MMP‐9 in cardiac fibroblasts in ischaemic areas at 10 and 21 days after MI. Cell culture experiments revealed that hypoxia increases LRP1, pPyk2 protein levels and MMP‐9 activity in fibroblasts, without significant changes in MMP‐2 activity. MMP‐9 activation by hypoxia requires LRP1 and Pyk2 phosphorylation in fibroblasts. Collectively, our in vivo and in vitro data support a major role of cardiac fibroblast LRP1 levels on MMP‐9 up‐regulation associated with ventricular remodelling after MI.
A Novel CXCR4 antagonist enhances angiogenesis via modifying the ischaemic tissue environment
Authors: Yan Xiaoqing , Dai Xiaozhen , He Luqing , Ling Xiao , Shao Minglong , Zhang Chi , Wang Yuehui , Xiao Jian , Cai Lu , Li Xiaokun , Tan Yi
Published: April 2017

Endothelial progenitor cells (EPCs) play a capital role in angiogenesis via directly participating in neo‐vessel formation and secreting pro‐angiogenic factors. Stromal cell‐derived factor 1 (SDF‐1) and its receptor CXCR4 play a critical role in the retention and quiescence of EPCs within its niche in the bone marrow. Disturbing the interaction between SDF‐1 and CXCR4 is an effective strategy for EPC mobilization. We developed a novel CXCR4 antagonist P2G, a mutant protein of SDF‐1β with high antagonistic activity against CXCR4 and high potency in enhancing ischaemic angiogenesis and blood perfusion. However, its direct effects on ischaemic tissue remain largely unknown. In this study, P2G was found to possess a robust capability to promote EPC infiltration and incorporation in neo‐vessels, enhance the expression and function of pro‐angiogenic factors, such as SDF‐1, vascular endothelial growth factor and matrix metalloprotein‐9, and activate cell signals involved in angiogenesis, such as proliferating cell nuclear antigen, protein kinase B (Akt), extracellular regulated protein kinases and mammalian target of rapamycin, in ischaemic tissue. Moreover, P2G can attenuate fibrotic remodelling to facilitate the recovery of ischaemic tissue. The capability of P2G in direct augmenting ischaemic environment for angiogenesis suggests that it is a potential candidate for the therapy of ischaemia diseases.
The impact of cortisol in steatotic and non‐steatotic liver surgery
Authors: Cornide‐Petronio María Eugenia , Bujaldon Esther , Mendes‐Braz Mariana , Avalos de León Cindy G. , Jiménez‐Castro Mónica B. , Álvarez‐Mercado Ana I. , Gracia‐Sancho Jordi , Rodés Juan , Peralta Carmen
Published: April 2017

The intent of this study was to examine the effects of regulating cortisol levels on damage and regeneration in livers with and without steatosis subjected to partial hepatectomy under ischaemia–reperfusion. Ultimately, we found that lean animals undergoing liver resection displayed no changes in cortisol, whereas cortisol levels in plasma, liver and adipose tissue were elevated in obese animals undergoing such surgery. Such elevations were attributed to enzymatic upregulation, ensuring cortisol production, and downregulation of enzymes controlling cortisol clearance. In the absence of steatosis, exogenous cortisol administration boosted circulating cortisol, while inducing clearance of hepatic cortisol, thus maintaining low cortisol levels and preventing related hepatocellular harm. In the presence of steatosis, cortisol administration was marked by a substantial rise in intrahepatic availability, thereby exacerbating tissue damage and regenerative failure. The injurious effects of cortisol were linked to high hepatic acethylcholine levels. Upon administering an α7 nicotinic acethylcholine receptor antagonist, no changes in terms of tissue damage or regenerative lapse were apparent in steatotic livers. However, exposure to an M3 muscarinic acetylcholine receptor antagonist protected livers against damage, enhancing parenchymal regeneration and survival rate. These outcomes for the first time provide new mechanistic insight into surgically altered steatotic livers, underscoring the compelling therapeutic potential of cortisol–acetylcholine–M3 muscarinic receptors.
Role of endothelial‐to‐mesenchymal transition induced by TGF‐β1 in transplant kidney interstitial fibrosis
Authors: Wang Zijie , Han Zhijian , Tao Jun , Wang Jun , Liu Xuzhong , Zhou Wanli , Xu Zhen , Zhao Chunchun , Wang Zengjun , Tan Ruoyun , Gu Min
Published: April 2017

Chronic allograft dysfunction (CAD) induced by kidney interstitial fibrosis is the main cause of allograft failure in kidney transplantation. Endothelial‐to‐mesenchymal transition (EndMT) may play an important role in kidney fibrosis. We, therefore, undertook this study to characterize the functions and potential mechanism of EndMT in transplant kidney interstitial fibrosis. Proteins and mRNAs associated with EndMT were examined in human umbilical vein endothelial cells (HUVECs) treated with transforming growth factor‐beta1 (TGF‐β1) at different doses or at different intervals with western blotting, qRT‐PCR and ELISA assays. Cell motility and migration were evaluated with motility and migration assays. The mechanism of EndMT induced by TGF‐β1 was determined by western blotting analysis of factors involved in various canonical and non‐canonical pathways. In addition, human kidney tissues from control and CAD group were also examined for these proteins by HE, Masson's trichrome, immunohistochemical, indirect immunofluorescence double staining and western blotting assays. TGF‐β1 significantly promoted the development of EndMT in a time‐dependent and dose‐dependent manner and promoted the motility and migration ability of HUVECs. The TGF‐β/Smad and Akt/mTOR/p70S6K signalling pathways were found to be associated with the pathogenesis of EndMT induced by TGF‐β1, which was also proven in vivo by the analysis of specimens from the control and CAD groups. EndMT may promote transplant kidney interstitial fibrosis by targetting the TGF‐β/Smad and Akt/mTOR/p70S6K signalling pathways, and hence, result in the development of CAD in kidney transplant recipients.
Placental growth factor silencing ameliorates liver fibrosis and angiogenesis and inhibits activation of hepatic stellate cells in a murine model of chronic liver disease
Authors: Li Xi , Yao Qun‐Yan , Liu Hong‐Chun , Jin Qian‐Wen , Xu Bei‐Li , Zhang Shun‐Cai , Tu Chuan‐Tao
Published: April 2017

Placental growth factor (PlGF) is a member of the vascular endothelial growth factor (VEGF) family and is involved in pathological angiogenesis associated with chronic liver diseases. However, the precise mechanisms underlying PlGF signalling contributing to liver fibrosis and angiogenesis remain largely unexplored. This study aimed to assess the effect of reducing PlGF expression using small interfering RNA (siRNA) on experimental liver fibrosis and angiogenesis, and to elucidate the underlying molecular mechanisms. Fibrosis was induced in mice by carbon tetrachloride (CCl4) for 8 weeks, and mice were treated with PlGF siRNA or non‐targeting control siRNA starting two weeks after initiating CCl4 injections. The results showed that PlGF was highly expressed in cirrhotic human and mice livers; which mainly distributed in activated hepatic stellate cells (HSCs). PlGF silencing robustly reduced liver inflammation, fibrosis, intrahepatic macrophage recruitment, and inhibited the activation of HSCs in vivo. Moreover, PlGF siRNA‐treated fibrotic mice showed diminished hepatic microvessel density and angiogenic factors, such as hypoxia‐inducible factor‐1α (HIF‐1α), VEGF and VEGF receptor‐1. Moreover, down‐regulation of PlGF with siRNA in HSCs inhibited the activation and proliferation of HSCs. Mechanistically, overexpression of PlGF in activated HSCs was induced by hypoxia dependent on HIF‐1α, and PlGF induces HSC activation and proliferation via activation the phosphatidylinositol 3‐kinase (PI3K)/Akt signalling pathways. These findings indicate that PlGF plays an important role in liver fibrosis‐associated angiogenesis and that blockage of PlGF could be an effective strategy for chronic liver disease.
The impact of the Affordable Care Act on hospital‐led community health evaluation in the U.S. Appalachian Ohio region
Authors: Franz Berkeley , Skinner Daniel , Kelleher Kelly
Published: April 2017

In recent years, policy developments in the United States have dramatically changed how nonprofit hospitals interact with surrounding communities. However, despite the importance of these changes encoded in Internal Revenue Service regulations, little is known about how these requirements have affected how nonprofit hospitals are approaching community health evaluation. We present qualitative findings from interviews with hospital employees and consultants overseeing preliminary rounds of community health needs assessments, as required by the Affordable Care Act. The sample comes from the Appalachian region of Ohio, an area targeted because of significant health challenges. Our findings suggest that the Affordable Care Act has led hospitals to formalize their processes, focus on developing an evidence base, cultivate local partnerships, and reflect on the role of the hospital in public health.
Multi‐temporal synthetic aperture radar flood mapping using change detection
Authors: Clement M.A. , Kilsby C.G. , Moore P.
Published: April 2017

A change detection and thresholding methodology has been adapted from previous studies to determine the extent of flooding for 13 Sentinel‐1 synthetic aperture radar images captured during the floods of winter 2015–2016 in Yorkshire, UK. Both available polarisations, VH and VV, have been processed to allow for a comparison of their respective accuracy for delineating surface water. Peak flood extents are found on 29 December 2015 during the aftermath of storms Eva and Frank. Results have been validated against a Sentinel‐2 optical image, with both polarisations producing a total accuracy of 97%. Of the two polarisations, VV produces fewer misclassifications, mirroring the similar results reported in previous research. Mapped results are compared to the Environment Agency Flood Maps for Planning (EA FMP), with good correlation observed for inundation on the floodplains. Differences occur away from the floodplains, with the satellite data identifying pluvial flooding not highlighted by the EA FMP.
Difficulty Managing Medications and Finances in Older Adults: A 10‐year Cohort Study
Authors: Bleijenberg Nienke , Smith Alexander K. , Lee Sei J. , Cenzer Irena Stijacic , Boscardin John W. , Covinsky Kenneth E.
Published: April 2017

Background

Difficulty managing medicines and finances becomes increasingly common with advanced age, and compromises the ability to live safely and independently. Remarkably little is known how often this occurs.

Objectives

To provide population‐based estimates of the risk of developing incident difficulty managing medications and finances in older adults.

Design

A prospective cohort study.

Setting

The Health and Retirement Study (HRS), a nationally representative study of older adults.

Participants

9,434 participants aged 65 and older who did not need help in managing medications or managing finances in 2002. Follow‐up assessments occurred every 2 years until 2012.

Measurements

The primary outcomes were time to difficulty managing medications and time to difficulty managing finances. Risk factors such as demographics, comorbidities, functional status, and cognitive status were assessed at baseline. Hazard models that considered the competing risk of death were used to estimate both the cumulative incidence of developing difficulty managing medications and finances and to identify potential risk factors. Analyses were adjusted for age, gender, race, marital status, wealth and education.

Results

The 10 years incidence of difficulty increased markedly with age, ranging from 10.3% (95% CI 9.3–11.6) for managing medications and 23.1% (95% CI 21.6–24.7) for managing finances in those aged 65–69, to 38.2% (95% CI 33.4–43.5) for medicines and 69% (95% CI 63.7–74.3) for finances in those over age 85. Women had a higher probability of developing difficulty managing medications and managing finances than men.

Conclusion

This study highlights the importance of preparing older adults for the likelihood they will need assistance with managing their medicines and finances as the risk for having difficulty with these activities over time is substantial.