Inducing critical phenomena in spin chains through sparse alternating fields

We analyze the phase diagram of the exact ground state (GS) of spin-s chains with ferromagnetic XXZ couplings under n-alternating field configurations, i.e., sparse alternating fields having nodes at n − 1 contiguous sites. It is shown that such systems can exhibit a nontrivial magnetic behavior, which can differ significantly from that of the standard (n = 1) alternating case and enable mechanisms for controlling their magnetic and entanglement properties. The boundary in field space of the fully aligned phase can be determined analytically ∀ n, and shows that it becomes reachable only above a threshold value of the coupling anisotropy Jz/J, which depends on n but is independent of the system size. Below this value, the maximum attainable magnetization becomes much smaller. We then show that the GS can exhibit significant magnetization plateaus, persistent for large systems, at which the magnetization per site m obeys the quantization rule 2n(s − m) = integer, consistent with the Oshikawa, Yamanaka, and Affleck criterion. We also identify the emergence of field-induced spin polymerization, which explains the presence of such plateaus. Entanglement and field-induced frustration effects are also analyze

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

Low incidence of congenital toxoplasmosis in children born to women infected with human immunodeficiency virus

In children born to immunocompetent women, congenital toxoplasmosis almost always results from primary infection during pregnancy. However, reactivation of latent toxoplasmosis during pregnancy could occur in HIV-infected pregnant women, particularly in those who are severely immunocompromised, and result in maternal-fetal transmission of the parasite. This mode of infection has been described in case reports but the risk of transmission is unknown. Findings on toxoplasmosis are presented from the European Collaborative Study, a prospective study of children born to women known to be HIV-infected at the time of delivery. In 1058 children followed for a mean duration of 35 months, only one child developed clinical toxoplasmosis. This child was HIV-infected, severely immunocompromised, and acquired toxop]asmosis postnatally. Congenital infection was excluded serologically in a subgroup of 167 children, of whom an estimated 71 had been at risk of infection. These clinical and serological findings indicate a low general risk of maternal-fetal transmission of Toxoplasma infection in HIV-infected women. It is not possible to draw conclusions about the risk of transmission for severely immunocompromised HIV-infected women because most women in the study were asymptomatic.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Neurologic signs in young children with human immunodeficiency virus infection

Neurologic and neurodevelopmental problems were investigated in a cohort of 39 human immunodeficiency virus (HIV)-infected children and 164 antibody-negative children born to HIV-positive women. All children were followed from birth for between 1 month and 4 years. Serious neurologic manifestations were present in 5 of 16 children (31%) who developed acquired immunodeficiency syndrome/acquired immunodeficiency syndrome-related complex, although in 2 the neurologic signs were probably not related to HIV. This can be compared with a prevalence of 0 of 23 in children who remained asymptomatic or who had less severe HIV-related symptoms or signs and 2 of 164 (1%) in uninfected children. Neurologic signs in the uninfected group were associated with the presence of drug withdrawal at birth and prematurity. These findings contrast with reports of a high prevalence of neurologic findings in most studies of HIV-infected children

Pequenos para idade gestacional: fator de risco para mortalidade neonatal Small for gestational age

OBJETIVO: Estudar as variáveis contempladas na Declaração de Nascimento (DN) como possíveis fatores de risco para nascimentos pequenos para a idade gestacional (PIG) e o retardo de crescimento intra-uterino como fator de risco para a mortalidade neonatal. MATERIAL E MÉTODO: As variáveis existentes na DN foram obtidas diretamente de prontuários hospitalares. Os dados referem-se a uma coorte de nascimentos obtida por meio da vinculação das declarações de nascimento e óbito, correspondendo a 2.251 nascimentos vivos hospitalares, de mães residentes, ocorridos no Município de Santo André, Região Metropolitana de São Paulo, no período de l/1 a 30/6/1992, e aos óbitos neonatais verificados nessa coorte. RESULTADOS: Obteve-se a proporção de 4,3% de nascimentos PIG, significativamente maior entre os recém-nascidos de pré-termo e pós-termo, entre os nascimentos cujas mães tinham mais de 35 anos de idade e grau de instrução inferior ao primeiro grau completo. Os recém-nascidos PIG apresentam maior risco de morte neonatal que aqueles que não apresentavam sinais de retardo de crescimento intra-uterino. CONCLUSÕES: Em áreas com menor freqüência de baixo peso ao nascer, é importante investigar a presença de retardo de crescimento intra-uterino entre os nascimentos prematuros e não apenas nos nascimentos de termo. O registro da data da última menstruação (ou da idade gestacional em semanas não agregadas na DN) facilitaria a detecção de PIGs na população de recém-nascidos.<br>INTRODUCTION: Variables of birth certificates were analysed as risk factors of SGA (Small for Gestational Age) infantis, and with a view to discovering if retarded intra-uterine growth was a risk factor neonatal mortality. MATERIAL AND METHOD: Data were obtained directly from 11 hospital medical records. A cohort of 2.251 hospital live births was obtained. Linkage of the death and birth certificates was undertaken to identify the neonatal deaths. The study was carried out in Santo André county in the S. Paulo Metropolitan area in the period from 1/1 to 30/6/1992. RESULTS: There were 4.3% of SGA live births. A higher statistically significant proportion of SGA was found in pre-term and post-term live births, among live births of mothers with 35 years of age and over and in those whose mothers had less than complete primary education. The SGA live births showed a higher risk of neonatal death, even when allowing for gestational age. CONCLUSIONS: In areas where there is a low proportion of low birthweight, the presence of retarded intra-uterine growth may be an important risk factor to pre-term live births, due to the association between the pre-term and SGA. It would be easier to evaluate signs of retarded intra-uterine growth in the live birth population, if the gestational age data were registered, on the birth certificate in weeks

Hospitalization of children born to human immunodeficiency virus- infected women in Europe

Objective. To describe the pattern of inpatient hospital service use in the first 5 years of life of all children born to HIV-infected women in 10 pediatric centers of the European Collaborative Study. Background. Little information is available on the need for hospitalization of children born to HIV-infected women, especially those uninfected, despite the fact that they may be at risk of social deprivation and poor health because of family cicumstances. Methods. Data on 1189 children enrolled between 1986 and 1997 and followed prospectively since birth according to a standard protocol were analyzed. Results. This analysis included 151 HIV-infected and 811 uninfected children. One hundred forty (12%) infants had delayed postnatal discharge, mainly for drug withdrawal symptoms and prematurity. Uninfected children had 0.5 admission per 5 child years compared with 2.4 for infected children. From life table analysis, an estimated 48% of infected and 17% of uninfected children will have been admitted by age 12 months. Nearly 60% (3304 of 5604) of the total inpatient days of infected children occurred after AIDS diagnosis. Infected children were 4 times more likely to be hospitalized than uninfected children of the same age, and children with symptomatic mothers were 13 times more likely to be admitted for a nonmedical reason. Conclusions. Whereas hospitalization of infected children poses an expected burden on the health care system, the use of such services by uninfected children is largely explained by their social background and provides an argument for better support for families affected by HIV.SCOPUS: ar.jinfo:eu-repo/semantics/publishe