Natural revegetation of placer mined lands of interior Alaska II

To the uninitiated eye an aerial photo of Fairbanks’ surrounding area includes patches of what might appear to be the channels left by the workings of a bark beetle grub. These series of parallel mounds with sequences of smaller undulations on their surfaces are actually composed of coarse gravel and are the product of some forty years of gold dredging. Started in 1928, dredging was concentrated in several of the tributary valleys of the Tanana River and Goldstream Creek. Some of these tailings piles support lush growth while others are relatively bare. At present, no ecologically oriented studies, either qualitative or quantitative, have been published concerning the gold dredge tailings. It was therefore the intent of this study to obtain a broad picture of the present stage of revegetation, in order that further ecological work and, hopefully, assisted rehabilitation may be facilitated.Introduction -- Methods -- Preliminary results -- Stands with little vegetation -- Intermediate stands -- Well developed stands -- Concluding remarks

Nanomolecular detection of human influenza virus type A using reverse transcription loop-mediated isothermal amplification assisted with rod-shaped gold nanoparticles

Reverse transcription loop-mediated isothermal amplification (RT-LAMP) and rod-shaped gold nanoparticles (gold nanorods; GNRs) were employed for nanomolecular detection of human influenza virus type A RNA. After cDNA synthesis from the RNA, the primers targeting the M protein gene were used for LAMP amplification. A blue shift from red to purple from the GNR inserting into the LAMP-DNAs can be seen by the naked eye. Transmission electron microscopy revealed the formation GNR aggregates due to their interactions with LAMP DNA. One pg RNA (10-3 dilution of the viral cDNA) was detected using this colorimetric test. The nanomolecular test showed 100% sensitivity and 95.8% specificity in comparison to results by RT-PCR. Also, the test indicated 100% sensitivity and 100% specificity in comparison to results by RT-LAMP. The described nanomolecular test could detect human influenza virus type A RNA in nearly 1 hour. This journal is © the Partner Organisations 2014

Agreement between ultrasonography and histopatologic findings in diagnosing retinoblastoma

Retinoblastoma is a rare eye tumor of childhood that represents the most common intraocular malignancy ofinfancy and childhood. Diagnosis of retinoblastoma are based on ophthalmological examination and imaging, includingultrasonography (USG). In a typical case of retinoblastoma, it will provide a nearly pathognomonic picture withcottage-cheese calcification, with density higher than the sclera and high internal reflectivity in USG findings.Histopathologic examination is a gold standard formalignany cases and Flexner-Wintersteiner cells is a pathognomonicsign. The aim of this study is to determine the value of an agreement test comparing USG as a preoperativediagnostic tool with histopatologic examination in diagnosing retinoblastoma. This study was an observationalagreement test. All of the patients with clinically suspected intraocular lession were examined with USG followedby surgery and histopathologic examination in Eye Clinic of Dr. Sardjito Hospital, Yogyakarta. The result of USGexaminationswas interpreted by one eye oncologist and the histopathologic readingwas performed by one anatomicalpathologist. Data were analyzed to determine the agreement value. Thirty three eyes, 21 eyes were retinoblastomasuspected and 12 eyes were non-retinoblastoma suspected based on USG examination), were observed in thisstudy. One eye (3.03%) was false positive case and 1 was false negative case. The Kappa value of agreement testwas 0.87. In conclusion, ultrasonography of the eye as a pre-operative diagnostic tool had an excellent agreementcompared with histopathological examination as a gold standard in retinoblastoma.Key words: eye-retina-intraocular malignancy-diagnosis-Kappa valu

Herbert Hoover: Only an Eye for Gold?

Herbert Hoover, 31st President of the United States, was a successful mining engineer and author prior to becoming president. Part of his mining engineering career was spent in the goldfields of Western Australia, where he has become part of the local folklore. Hoover allegedly had an eye for the ladies and fell in love with a barmaid to whom he wrote a love poem

Gold-Nanoparticle-Based Colorimetric Discrimination of Cancer-Related Point Mutations with Picomolar Sensitivity

Point mutations in the Kirsten rat sarcoma viral oncogene homologue (KRAS) gene are being increasingly recognized as important diagnostic and prognostic markers in cancer. In this work, we describe a rapid and low-cost method for the naked-eye detection of cancer-related point mutations in KRAS based on gold nanoparticles. This simple colorimetric assay is sensitive (limit of detection in the low picomolar range), instrument-free, and employs nonstringent room temperature conditions due to a combination of DNA-conjugated gold nanoparticles, a probe design which exploits cooperative hybridization for increased binding affinity, and signal enhancement on the surface of magnetic beads. Additionally, the scheme is suitable for point-of-care applications, as it combines naked-eye detection, small sample volumes, and isothermal (PCR-free) amplification

Agreement between ultrasonography and histopatologic findings in diagnosing retinoblastoma

Retinoblastoma is a rare eye tumor of childhood that represents the most common intraocular malignancy of infancy and childhood. Diagnosis of retinoblastoma are based on ophthalmological examination and imaging, including ultrasonography (USG). In a typical case of retinoblastoma, it will provide a nearly Rathognomonic picture with cottagecheese calcification, with density higher than the sclera and high internal reflectivity in USG findings. Histopathologic examination is a gold standard for malignany cases and Flexner-Wintersteiner cells is a pathognomonic sign. The aim of this study is to determine the value of an agreement test comparing USG as a preoperative diagnostic tool with histopatologic examination in diagnosing retinoblastoma. This study was an observational agreement test. All of the patients with clinically suspected intraocular lession were examined with USG followed by surgery and histopathologic examination in Eye Clinic of Dr. Sardjito Hospital, Yogyakarta. The result of USG examinations was interpreted by one eye oncologist and the histopathologic reading was performed by one anatomical pathologist. Data were analyzed to determine the agreement value. Thirty three eyes, 21 eyes were retinoblastoma suspected and 12 eyes were nonretinoblastoma suspected based on USG examination), were observed in this study. One eye (3.03%) was false positive case and 1 was false negative case. The Kappa value of agreement test was 0.87. In conclusion, ultrasonography of the eye as a pre-operative diagnostic tool had an excellent agreement compared with histopathological examination as a gold standard in retinoblastoma

Occupational exposure risk to radiation in open cast artisanal and small-scale gold mining in Western Kenya

Artisanal and small-scale gold mining (ASSGM) is practiced at open-cast gold mines in Western Kenya. Mining is still going on in deep mines, with huge tailings littering the workplace for most miners. This mining exercise brings to the surface myriad radioactive materials from the earth’s crust, which pose physical and radiation hazards to miners. The aim of this study was to determine occupational exposure to radiation at artisanal gold mining sites. Four sites were studied for a period of six months. Environmental radiation exposure levels were measured using the Geiger Mueller tube (GMT) model; PHYWE, whereas thermoluminescent dosimeter badges (TLB) 802A were used to record personal radiation exposure levels. d-Orbital Limited Company provided UD-716AGL, used to read the radiation levels from the TLB. Exposure levels were reported in terms of monthly skin, eye, and body exposures. Results revealed an increase in counts per minute with an increase in depth in a range of 19.83 ± 3.87 to 27.83 ± 2.10 and a mean of 23.62 ± 5.17 cpm. Personal effective radiation exposure doses for the skin, eye and body were 0.19 ± 0.01, 0.19 ± 0.01 and 0.18 ± 0.015 for two sites in Western Kenya, whereas those in Nyanza had 0.27 ± 0.01, 0.27 ± 0.01 and 0.25 ± 0.05 mSv on skin, eye and body. The maximum dose threshold limit was estimated at 1.67 mSv per month. There was no significant difference in the radiation exposure of the eye, skin, and body between the sites as indicated by χ2 = 2.0 and p = 0.157 (at p<0.05) with df = 1. The study revealed that workers are exposed to ionising radiation, but the measured levels were within safe limits