Temperature effect on phosphate sorption by iron hydroxide

The ion exchange sorption of phosphate on Fe(OH)3 is studied as a function of temperature (25-55 degrees C) and concentration (1.49-3.23 mmol l(-1)). The mechanism of sorption is observed to be the exchange of OH- anions from the adsorbent surface by those of H2PO4- and HPO4(2-) from the aqueous solution. An equation developed in the Langmuir formalism is used to explain the ion exchange sorption of phosphate on Fe(OH)3. The isosteric heat of sorption illustrates that the uptake of phosphate on Fe(OH)3 takes place through an anion exchange process, involving both the phosphate anions H2PO4- and HPO4(2-). Further, at higher temperature the solid prefers the HPO4(2-) anions forming a binuclear bridging complex.

Milk progesterone profiles in various reproductive states in dairy buffaloes under field conditions

Fifty-one dairy buffaloes in the last two months of gestation were selected at seven private peri-urban farms in the Peshawar district. Observations were recorded in buffaloes during normal (NBS, August to January) and low breeding seasons (LBS, February to July). After parturition, rectal examination of reproductive organs was carried out. Estrus detection was made through visual observation and the use of intact bull. Postpartum ovulation was confirmed by ovarian palpation per rectum and milk progesterone levels (MPL), determined through radio-immunoassay. MPL was higher (p < 0.01) at various intervals in NBS calves (1.97 +/- 0.30 ng/ml) as compared to LBS calves (0.68 +/- 0.08 ng/ml). During LBS, MPL remained < 0.30 ng/ml up to the third fortnight and started rising later, reaching a peak of 1.27 ng/ml during the sixth fortnight. During NBS, there was a sharp rise in MPL during the second fortnight, reaching 3.64 ng/ml during the sixth fortnight. MPL was significantly different on different experimental farms (p < 0.01). MPL reached the lowest levels on the day of estrus (0.10 ng/ml), reached it's peak on day 7 and started declining on day 17 of estrus. MPL showed two postpartum elevations. In true anestrus buffaloes, MPL remained consistently low. However, in the anestrus period, silent ovulations were also noted, as reflected by increasing MPL without estrus signs. In pregnant buffaloes, MPL remained > 1 ng/ml. Results of the study showed that the low postpartum reproductive performance in dairy buffaloes during LBS was primarily due to inadequate functioning of the corpus luteum in secreting optimum concentrations of progesterone. The higher incidence of silent estrus during LBS indicated improved management for the detection of estrus.

Prevalence of anaemia in semi-urban areas of Peshawar, Pakistan: a challenge for health professionals and policy makers

Iron deficiency anaemia is a serious problem among Pakistani children. Pre-intervention haematological status of children under two years was assessed as part of a double-blind, randomized controlled community-based study conducted in two semi-urban areas of Peshawar. The primary objective was to assess the impact of iron deficiency anaemia and iron intervention on growth and morbidity. Three hundred and twenty children who met the criteria of a "healthy child" were recruited for the study. Blood samples were drawn from 275 children for haemoglobin (Hb) and serum ferritin (SF) analyses. The children were classified as anaemic (Hb < 11 g/dl); iron deficient (SF < 12 ng/ml) and iron deficient anaemic (Hb < 11 g/dl and SF < 12 ng/ml). Ninety percent of the children were anaemic, 67% iron deficient and 63% iron deficient anaemic. Anaemia was more prevalent in boys who had significantly lower Hb and SF values than girls. The magnitude of anaemia in these children tended to increase with age. The study demonstrates that iron deficiency is the predominant cause of anaemia (69%) in children under two years. Minimization of iron deficiency anaemia should be a public health priority in order to prevent suffering of children and avert the associated cognitive and physical deficits in child development.

Effect of iron supplementation on biochemical indices of iron status in selected pre-adolescent schoolgirls in North West Frontier Province, Pakistan

A study was carried out on eight to 11 year old schoolgirls to assess the prevalence of iron deficiency anemia (IDA) and to study the impact of iron supplementation on the biochemical indices of iron status. The children were characterized iron deficient anemic if their serum ferritin levels (SF) were <= 12 ng/ml and hemoglobin (Hb) < 12 g/dl or hematocrit (Hct) <= 35%. In a double blind trial, the anemic and non-anemic children were randomly selected for the treatment and control groups. All the groups received multivitamin tablets daily, the treatment group received an additional 76 mg elemental iron per day for 11 weeks. The prevalence of IDA in these children was found to be 35% . The supplementation caused a significantly (P<0.05) greater change in SF (20 ng/ml); Hb (1.5 g/dl) and Hct (3%) of the anemic treatment group compared to the corresponding control group. The non-anemic treatment group also showed a significantly greater change in SF (9 ng/ml); Hb (0.78 g/ dl) and Hct (1.3%) than that of the control group. An increase in biochemical indices of the nonanemic treatment indicates that this group's initial iron status was only marginally adequate.