Photonic crystals built by time in ancient Roman glass

Ancient glass objects typically show distinctive effects of deterioration as a result of environmentally induced physicochemical transformations of their surface over time. Iridescence is one of the distinctive signatures of aging that is most commonly found on excavated glass. In this work, we present an ancient glass fragment that exhibits structural color through surface weathering resulting in iridescent patinas caused by silica reprecipitation in nanoscale lamellae. This archaeological artifact reveals an unusual hierarchically assembled photonic crystal with extremely ordered nanoscale domains, high spectral selectivity, and reflectivity (~90%), that collectively behaves like a gold mirror. Optical characterization paired with nanoscale elemental analysis further underscores the high quality of this structure providing a window into this sophisticated natural photonic crystal assembled by time.

Anemia and iron deficiency in adolescent school girls in kavar urban area, southern iran

BACKGROUND

Anemia is one of the most common public health problems especially in developing countries. We investigated the prevalence of anemia, iron deficiency anemia and related risk factors in adolescent school girls in Kavar urban area in southern Iran.

METHODS

A total of 363 adolescent school girls were evaluated by a cross sectional study. Socioeconomic, demographic and related risk factors were obtained by a questionnaire. Hematological parameters and serum iron indices were measured.

RESULTS

There were 21 cases of anemia (5.8%), 31 (8.5%) iron deficiency and 6 (1.7%) iron deficiency anemia.  Most of anemic girls (85.7%) had mild anemia.  MCV, TIBC, age, and BMI had statistically significant relationship with hemoglobin. Only parasites infestation in the last three months had a 6.83 times more risk of anemia than those without this history (95% CI, 1.66-28.11).

CONCLUSION

The prevalence of anemia and iron deficiency anemia in this study were substantially less than what reported in many other regions of Iran as well as other developing countries. It seems that related implemented strategies in the recent years have been successful. More especial attention to prevention of parasite infestation should be considered in this area.

Initial presentation of acute lymphoblastic leukemia with osteoporosis and multiple spontaneous bone fractures

Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy. Skeletal abnormalities have been described in association with ALL including osteoprosis and bone fractures. Different factors including the disease itself or soluble products of malignant cells and treatment agents like cytotoxic drugs, methotroxate, corticosteroids and radiotherapy may be responsible for defective bone homeostasis in these patients. Orthopedic conditions and pain may be the first manifestation of acute leukemia and it is important for physicians to recognize the skeletal manifestation of acute childhood leukemia because of a delay in diagnosis has adverse effect on survival. We present a child with ALL that refer with multi bone fractures as a first manifestation of the disease.