The Lempel–Ziv universal coding scheme is asymptotically optimal for the class of all stationary ergodic sources. A problem of robustness of this property under small violations of ergodicity is studied. A notion of deficiency of algorithmic randomness is used as a measure of disagreement between data sequence and probability measure. We prove that universal compressing schemes from a large cla...

Recent evidence for the nonskeletal effects of vitamin D, coupled with recognition that vitamin D deficiency is common, has revived interest in this hormone. Vitamin D is produced by skin exposed to ultraviolet B radiation or obtained from dietary sources, including supplements. Persons commonly at risk for vitamin D deficiency include those with inadequate sun exposure, limited oral intake, or...

OBJECTIVE Whether vitamin D deficiency and insufficiency are associated with childhood asthma remains unclear. Thus, we conducted a meta-analysis to summarize the evidence from epidemiological studies of vitamin D deficiency and insufficiency and the risk of childhood asthma. METHODS Pertinent studies were identified by searching of PubMed and Web of Knowledge. The random effect model was use...

Many children in low- and middle-income countries may have inadequate intake of vitamin B12 and folate; data confirming these inadequacies are limited. We used biochemical, demographic, behavioral and anthropometric data to describe the folate and vitamin B12 concentrations among six- to 23-month-old Nepalese children. Vitamin B12 (serum B12 < 150 pmol/L) and folate deficiencies (red blood cell...

UNLABELLED Chronic liver disease (CLD) and several related extrahepatic manifestations such as hepatic osteodystrophy are associated with deficiency of vitamin D, which has therefore been suggested as therapeutic target. Vitamin D undergoes hepatic 25-hydroxylation, rendering the liver critical to the metabolic activation of this vitamin. Vitamin D deficiency is highly prevalent in CLD patients...

The Lempel–Ziv universal coding scheme is asymptotically optimal for the class of all stationary ergodic sources. A problem of robust-ness of this property under small violations of ergodicity is studied. A notion of deficiency of algorithmic randomness is used as a measure of disagreement between data sequence and probability measure. We prove that universal compressing schemes from a large cl...

Vitamin D deficiency affects persons of all ages. Common manifestations of vitamin D deficiency are symmetric low back pain, proximal muscle weakness, muscle aches, and throbbing bone pain elicited with pressure over the sternum or tibia. A 25-hydroxyvitamin D level should be obtained in patients with suspected vitamin D deficiency. Deficiency is defined as a serum 25-hydroxyvitamin D level of ...

OBJECTIVE To review the literature about the prevalence of vitamin D deficiency and its consequences in children and adolescents with sickle-cell disease. DATA SOURCES The literature survey was performed through the bibliographic databases Medline; U.S. National Library of Medicine and National Institutes of Health (PubMed); Literatura Latino-Americana e do Caribe em Ciências da Saúde (Lilacs...

Calcium: What is it? What is the recommended intake for calcium? What foods provide calcium? Helping hints for meeting your calcium needs What affects calcium absorption and excretion? Calcium's role in health and disease prevention When can a calcium deficiency occur? Is there a health risk of too much calcium? Calcium and Medication Interactions Supplemental sources of calcium References Revi...