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Predictors of Stunting, Wasting and Underweight among Tanzanian Children Born to HIV-Infected Women.
Children born to human immunodeficiency virus (HIV)-infected women are susceptible to undernutrition, but modifiable risk factors and the time course of the development of undernutrition have not been well characterized. The objective of this study was to identify maternal, socioeconomic and child characteristics that are associated with stunting, wasting and underweight among Tanzanian children born to HIV-infected mothers, followed from 6 weeks of age for 24 months. Maternal and socioeconomic characteristics were recorded during pregnancy, data pertaining to the infant's birth were collected immediately after delivery, morbidity histories and anthropometric measurements were performed monthly. Multivariate Cox proportional hazards methods were used to assess the association between potential predictors and the time to first episode of stunting, wasting and underweight. A total of 2387 infants (54.0% male) were enrolled and followed for a median duration of 21.2 months. The respective prevalence of prematurity (<37 weeks) and low birth weight (<2500 g) was 15.2% and 7.0%; 11.3% of infants were HIV-positive at 6 weeks. Median time to first episode of stunting, wasting and underweight was 8.7, 7.2 and 7.0 months, respectively. Low maternal education, few household possessions, low infant birth weight, child HIV infection and male sex were all independent predictors of stunting, wasting and underweight. In addition, preterm infants were more likely to become wasted and underweight, whereas those with a low Apgar score at birth were more likely to become stunted. Interventions to improve maternal education and nutritional status, reduce mother-to-child transmission of HIV, and increase birth weight may lower the risk of undernutrition among children born to HIV-infected women
Perspective on Reversible to Irreversible Transitions in Periodic Driven Many Body Systems and Future Directions For Classical and Quantum Systems
Reversible to irreversible (R-IR) transitions arise in numerous periodically
driven collectively interacting systems that, after a certain number of driving
cycles, organize into a reversible state where the particle trajectories
repeat, or remain irreversible with chaotic motion. R-IR transitions were first
systematically studied for periodically sheared dilute colloids, and appear in
a wide variety of both soft and hard matter systems, including amorphous
solids, crystals, vortices in type-II superconductors, and magnetic textures.
In some cases, the reversible transition is an absorbing phase transition with
a critical divergence in the organization time scale. R-IR systems can store
multiple memories and exhibit return point memory. We give an overview of R-IR
transitions including recent advances in the field, and discuss how the general
framework of R-IR transitions could be applied to a much broader class of
periodically driven nonequilibrium systems, including soft and hard condensed
matter systems, astrophysics, biological systems, and social systems. Some
likely candidate systems are commensurate-incommensurate states, systems
exhibiting hysteresis or avalanches, and nonequilibrium pattern forming states.
Periodic driving could be applied to hard condensed matter systems to see if
R-IR transitions occur in metal-insulator transitions, semiconductors, electron
glasses, electron nematics, cold atom systems, or Bose-Einstein condensates.
R-IR transitions could also be examined in dynamical systems where
synchronization or phase locking occurs. We discuss the use of complex periodic
driving such as changing drive directions or multiple frequencies as a method
to retain complex multiple memories. Finally, we describe features of classical
and quantum time crystals that could suggest the occurrence of R-IR transitions
in these systems.Comment: 25 pages, 27 figure
Phase diagram of multiferroic KCuAsO(OD)
The layered compound KCuAsO(OD), comprising distorted kagome
planes of Cu ions, is a recent addition to the family of type-II
multiferroics. Previous zero field neutron diffraction work has found two
helically ordered regimes in \kns, each showing a distinct coupling between the
magnetic and ferroelectric order parameters. Here, we extend this work to
magnetic fields up to ~T using neutron powder diffraction, capacitance,
polarization, and high-field magnetization measurements, hence determining the
phase diagram. We find metamagnetic transitions in both low temperatures
phases around ~T, which neutron powder diffraction reveals
to correspond to a rotation of the helix plane away from the easy plane, as
well as a small change in the propagation vector. Furthermore, we show that the
sign of the ferroelectric polarization is reversible in a magnetic field,
although no change is observed (or expected on the basis of the magnetic
structure) due to the transition at ~T. We finally justify the temperature
dependence of the polarization in both zero-field ordered phases by a symmetry
analysis of the free energy expansion
Recovery from severe mental health problems: a systematic review of service user and informal caregiver perspectives
Introduction: The recovery approach aims to have users' perspectives at the heart of service development and research; it is a holistic perspective that considers social needs, personal growth and inclusion. In the last decade recovery-oriented research and practice has increased greatly, however, a comprehensive model of recovery considering exclusively the perspectives of people with lived experience has not been devised. Aims: This review aimed to develop a framework and contextualize service users' and informal caregivers' understanding of recovery from severe mental health problems. Methods: We systematically searched 6 databases including key terms related to knowledge, experience and narratives AND mental health AND personal recovery. The search was supplemented with reference sourcing through gray literature, reference tracking and expert consultation. Data analysis consisted of a qualitative meta-synthesis using constant comparative methods. Results: Sixty-two studies were analyzed. A pattern emerged regarding the recovery paradigms that the studies used to frame their findings. The resulting recovery framework included the domains Social recovery; Prosperity (Legal, political, and economic recovery); Individual Recovery; and Clinical Recovery Experience (SPICE). Service users' definitions of recovery tended to prioritize social aspects, particularly being accepted and connecting with others, while caregivers focused instead on clinical definitions of recovery such as symptom remission. Both groups emphasized individual aspects such as becoming self-sufficient and achieving personal goals, which was strongly linked with having economic means for independence. Conclusions: The recovery model provided by this review offers a template for further research in the field and a guide for policy and practice. Predominant definitions of recovery currently reflect understandings of mental health which focus on an individual perspective, while this review found an important emphasis on socio-political aspects. At the same time, only a small number of studies took place in low-income countries, focused on minoritized populations, or included caregivers' perspectives. These are important gaps in the literature that require further attention. Systematic Review Registration: The review protocol was registered on PROSPERO (CRD42017076450); https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=76450
Strong quantum fluctuation of vortices in the new superconductor
By using transport and magnetic measurement, the upper critical field
and the irreversibility line has been determined. A
big separation between and has been found showing the
existence of a quantum vortex liquid state induced by quantum fluctuation of
vortices in the new superconductor . Further investigation on the
magnetic relaxation shows that both the quantum tunneling and the thermally
activated flux creep weakly depends on temperature. But when the melting field
is approached, a drastic rising of the relaxation rate is observed.
This may imply that the melting of the vortex matter at a finite temperature is
also induced by the quantum fluctuation of vortices.Comment: 4 pages, 4 figure
Non-overlapping Distributed Tracking System Utilizing Particle Filter
Tracking people across multiple cameras is a challenging research area in visual computing, especially when these cameras have non-overlapping field of views. The important task is to associate a current subject with other prior appearances of the same subject across time and space in a camera network. Several known techniques rely on Bayesian approaches to perform the matching task. However, these approaches do not scale well when the dimension of the problem increases; e.g. when the number of subject or possible path increases. The aim of this paper is to propose a unified tracking framework using particle filters to efficiently switch between visual tracking (field of view tracking) and track prediction (non-overlapping region tracking). The particle filter tracking system utilizes a map (known environment) to assist the tracking process when targets leave the field of view of any camera. We implemented and tested this tracking approach in an in-house multiple cameras system as well as using on-line data. Promising results were obtained which suggested the feasibility of such an approach
Nucleation of Stable Superconductivity in YBCO-Films
By means of the linear dynamic conductivity, inductively measured on
epitaxial films between 30mHz and 30 MHz, the transition line to
generic superconductivity is studied in fields between B=0 and 19T. It follows
closely the melting line described recently in terms of a blowout of
thermal vortex loops in clean materials. The critical exponents of the
correlation length and time near , however, seem to be dominated by
some intrinsic disorder. Columnar defects produced by heavy-ion irradiation up
to field-equivalent-doses of lead to a disappointing reduction
of while for the generic line of the pristine film
is recovered. These novel results are also discussed in terms of a loop-driven
destruction of generic superconductivity.Comment: 11 pages including 7 EPS figures, accepted for publication in the
Proceedings of the Spring Meeting of the German Physical Society, Muenster
1999,Festkoerperprobleme/Advances in Solid State Physics 199
Cohort profile: the Nigerian HIV geriatric cohort study
Background: The Nigerian HIV Geriatric Cohort (NHGC) is a longitudinal cohort setup to learn how elderly people living with HIV (EPLHIV) in Nigeria fare, despite not being prioritized by the national treatment program, and to deepen knowledge for their differentiated care and achieve better outcomes. In this paper, we describe data collected on sociodemographic and clinical data from EPLHIV from the inception of Nigeria’s national HIV program to 2018. Methods: Patient-level data spanning the period 2004 to 2018, obtained from comprehensive HIV treatment hospitals, that are supported by four major PEPFAR-implementing partners in Nigeria were used. These 4 entities collaborated as member organizations of the Nigeria Implementation Science Alliance. We defined elderly as those aged 50 years and above. From deidentified treatment records, demographic and clinical data of EPLHIV ≥50-year-old at ART initiation during the review period was extracted, merged into a single REDcap® database, and described using STATA 13. Results: A total of 101,652 EPLHIV were analysed. Women accounted for 53,608 (53%), 51,037 (71%) of EPLHIV identified as married and 33,446 (51%) unemployed. Median age was 57.1 years (IQR 52–60 years) with a median duration on ART treatment of 4.1 years (IQR 1.7–7.1 years). ART profile showed that 97,586 (96%) were on 1st-line and 66,125 (65%) were on TDF-based regimens. Median body mass index (BMI) was 22.2 kg/m2 (IQR 19.5–25.4 kg/m2) with 43,012 (55%), 15,081 (19%) and 6803 (9%) showing normal (BMI 18.5 – 140 mmHg or diastolic-BP > 90 mmHg) was 16,201 (21%). EPLHIV median CD4 count was 381 cells/μL (IQR 212–577 cells/μL) and 26,687 (82%) had a viral load result showing < 1000copies/ml within one year of their last visit. As for outcomes at their last visit, 62,821 (62%) were on active-in-treatment, 28,463 (28%) were lost-to-follow-up, 6912 (7%) died and 2456 (3%) had stopped or transferred out. Poor population death records and aversion to autopsies makes it almost impossible to estimate AIDS-related deaths. Conclusions: This cohort describes the clinical and non-clinical profile of EPLHIV in Nigeria. We are following up the cohort to design and implement intervention programs, develop prognostic models to achieve better care outcomes for EPLHIV. This cohort would provide vital information for stakeholders in HIV prevention, care and treatment to understand the characteristics of EPLHIV
Is there a vortex-glass transition in high-temperature superconductors?
We show that DC voltage versus current measurements of a YBCO micro-bridge in
a magnetic field can be collapsed onto scaling functions proposed by Fisher,
Fisher, and Huse, as is widely reported in the literature. We find, however,
that good data collapse is achieved for a wide range of critical exponents and
temperatures. These results strongly suggest that agreement with scaling alone
does not prove the existence of a phase transition. We propose a criterion to
determine if the data collapse is valid, and thus if a phase transition occurs.
To our knowledge, none of the data reported in the literature meet our
criterion.Comment: 4 pages, 4 figure
Ultrametric spaces of branches on arborescent singularities
Let be a normal complex analytic surface singularity. We say that is
arborescent if the dual graph of any resolution of it is a tree. Whenever
are distinct branches on , we denote by their intersection
number in the sense of Mumford. If is a fixed branch, we define when and
otherwise. We generalize a theorem of P{\l}oski concerning smooth germs of
surfaces, by proving that whenever is arborescent, then is an
ultrametric on the set of branches of different from . We compute the
maximum of , which gives an analog of a theorem of Teissier. We show that
encodes topological information about the structure of the embedded
resolutions of any finite set of branches. This generalizes a theorem of Favre
and Jonsson concerning the case when both and are smooth. We generalize
also from smooth germs to arbitrary arborescent ones their valuative
interpretation of the dual trees of the resolutions of . Our proofs are
based in an essential way on a determinantal identity of Eisenbud and Neumann.Comment: 37 pages, 16 figures. Compared to the first version on Arxiv, il has
a new section 4.3, accompanied by 2 new figures. Several passages were
clarified and the typos discovered in the meantime were correcte
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