A New Very Sensitive and Selective Spot Test for Mercury

A sensitive and selective test for the detection of mercury has been developed based on the strong catalytic action of mercuric ions on the decomposition of hexacyanoferrate (II) in the presence of nitrosobenzene. The sensitivity for the pure system expressed as limit of identification (in 0.05 ml.) is 0.002 microgram of mercury at a limiting concentration o f 1 to 25,000.000. Of the cations studied only silver and gold give an analogous reaction. By following an appropriate procedure, mercury can be detected even when it is present in mixtures with cations giving coloured precipitates with the hexacyanoferrnte (II)

First record of a pregnant female little sleeper shark Somniosus rostratus (Risso, 1826) on the Spanish Mediterranean coast

This present paper records the catch of a pregnant female little sleeper shark Somniosus rostratus (Risso, 1826) in the waters of the Catalan continental slope (Spain). Eight embryos were found inside the animal. This is the first record of a pregnant female S. rostratus in the western Mediterranean.Se señala la captura de una hembra de tiburón dormilón Somniosus rostratus (Risso, 1826) frente a las costas de Cataluña (España). Dicho ejemplar estaba grávido y era portador de ocho embriones. éste es el primer registro de una hembra preñada de esta especie en el Mediterráneo occidental.Instituto Español de Oceanografí

A New Very Sensitive and Selective Spot Test for Mercury

A sensitive and selective test for the detection of mercury has been developed based on the strong catalytic action of mercuric ions on the decomposition of hexacyanoferrate (II) in the presence of nitrosobenzene. The sensitivity for the pure system expressed as limit of identification (in 0.05 ml.) is 0.002 microgram of mercury at a limiting concentration o f 1 to 25,000.000. Of the cations studied only silver and gold give an analogous reaction. By following an appropriate procedure, mercury can be detected even when it is present in mixtures with cations giving coloured precipitates with the hexacyanoferrnte (II)

Photometric Determination of Microquantities of Cyanides

The catalytic action of mercuric ions upon the reaction of potassium ferrocyanide and nitrosobenzene is strongly inhibited by even small concentrations of cyanide ions. The progress of the inhibitive effect may be observed by measuring the extinction of the violet reaction product [Fe(CN)5NOPh)3. A method for the quantitative photometric determination of microquantities of cyanides has been developed. The coefficient of variation for a concentration of 1x10-5 - 8x10-5 M /l of cyanide ion is shown to be 1.0 - 6.3%

Surprising applications and possible extensions of Dellsarte's method

Paper presented at Strathmore International Math Research Conference on July 23 - 27, 2012This is a short informal survey on some surprising applications of Delsarte's method, written for anyone being interested. I try to keep it as short and as informative as possibleThis is a short informal survey on some surprising applications of Delsarte's method, written for anyone being interested. I try to keep it as short and as informative as possibl

Haptoglobin Polymorphism: A Novel Genetic Risk Factor for Celiac Disease Development and Its Clinical Manifestations

Background: Haptoglobin (Hp) α-chain alleles 1 and 2 account for 3 phenotypes that may influence the course of inflammatory diseases via biologically important differences in their antioxidant, scavenging, and immunomodulatory properties. Hp1-1 genotype results in the production of small dimeric, Hp2-1 linear, and Hp2-2 cyclic polymeric haptoglobin molecules. We investigated the haptoglobin polymorphism in patients with celiac disease and its possible association to the presenting symptoms. Methods: We studied 712 unrelated, biopsy-proven Hungarian celiac patients (357 children, 355 adults; severe malabsorption 32.9%, minor gastrointestinal symptoms 22.8%, iron deficiency anemia 9.4%, dermatitis herpetiformis 15.6%, silent disease 7.2%, other 12.1%) and 384 healthy subjects. We determined haptoglobin phenotypes by gel electrophoresis and assigned corresponding genotypes. Results: Hp2-1 was associated with a significant risk for celiac disease (P = 0.0006, odds ratio [OR] 1.54, 95% CI 1.20–1.98; prevalence 56.9% in patients vs 46.1% in controls). It was also overrepresented among patients with mild symptoms (69.2%) or silent disease (72.5%). Hp2-2 was less frequent in patients than in controls (P = 0.0023), but patients having this phenotype were at an increased risk for severe malabsorption (OR 2.21, 95% CI 1.60–3.07) and accounted for 45.3% of all malabsorption cases. Celiac and dermatitis herpetiformis patients showed similar haptoglobin phenotype distributions. Conclusions: The haptoglobin polymorphism is associated with susceptibility to celiac disease and its clinical presentations. The predominant genotype in the celiac population was Hp2-1, but Hp2-2 predisposed to a more severe clinical course. The phenotype-dependent effect of haptoglobin may result from the molecule’s structural and functional properties

Accelerating progress towards the SDGs: Collaborative policymaking in sanitation for integrated benefits in Sub-Saharan Africa

In 2020, 54% of the world had access to safe sanitation, but access further reduces to 21% in sub-Saharan Africa . With only eight years left to meet the Sustainable Development Goals (SDGs), there is an urgent need to accelerate action in the sanitation sector. Previous academic research highlights sanitation as vital for supporting cross-cutting outcomes in health, economics, climate, gender equality, and the environment. However, there is a gap in knowledge outputs for policymakers to highlights how action in sanitation can leverage investment from agencies and ministries to achieve multiple SDGs. Our transdisciplinary team (academics, policymakers, and practitioners) co-developed actionable outputs for diverse audiences to fill this gap, building on an existing global evidence review identifying 130 synergies between sanitation and the SDGs. We identified priority focus areas influencing sanitation policies and financing in Sub-Saharan Africa to collaboratively develop visual aids, policy briefs, and this academic publication to engage cross-sectoral audiences. Our approach offers insights into the value of theoretical knowledge for policy outcomes in the sanitation sector. It is most likely that SDG6 Targets particularly related to sanitation will not be met by 2030 as the sector suffers from under investment. Co-creation between academia and the development sector is critical for consolidating knowledge/research and development practice to influence investment, progress and innovation

Reef Coral Reproduction in the Eastern Pacific: Costa Rica, Panamá, and the Galápagos Islands (Ecuador). VI. Agariciidae, Pavona clavus

The reproductive ecology of the zooxanthellate reef coral Pavona clavus was investigated at several sites in Costa Rica, Panama, and the Galapagos Islands (Ecuador) over the period 1985–2009. Pavona clavus displayed stable gonochorism as only five hermaphrodites were found in 590 samples. At four of five locations, sex ratios were skewed toward female dominance; however, at Saboga Island (Panama) male colonies predominated. In Panama, sexual maturity was observed in an estimated eight year old female colony, and several colonies of 10–20 years of age demonstrated gametogenesis. Sexual activity was observed at all study sites, but gamete development occurred in only 14–31% of colonies sampled sporadically. Seasonality of gametogenic activity occurred predominantly during the warm/wet season, June to August, at mainland sites (Cano Island, Costa Rica, and Gulfs of Chiriqui and Panama, Panama). This pattern was repeated in the Galapagos Islands, but mainly from March to May when seasonally high sea temperatures and rainfall prevailed there. Histological sampling and field observations indicated that spawning was centered around the full moon, most frequently on lunar day 17, and near sunset (1,800 h). Mean fecundity (mature ova cm-2 live tissue) estimates were significantly different for two sites and ranged from ~1,780 (Saboga Island, Gulf of Panama, seasonally upwelling) to ~4,280 (Uva Is, Gulf of Chiriqui, nonupwelling). Assuming three annual spawning events colony-1 (August, September, October), extrapolation of minimum and maximum fecundities yield 5,340 and 12,840 ova cm-2 year-1. Seasonal, lunar, and diel spawning patterns in nine zooxanthellate species at Uva Island indicate asynchronous coral community spawning