Influence of pore fluid salinity on shrinkage and water retention characteristics of biochar amended kaolin for landfill liner application.

Biochar amended clay layer has emerged as a sustainable hydraulic barrier for hazardous municipal waste containment system. The effects of pore fluid salinity on soil shrinkage and water retention characteristics of biochar amended clay are unknown. This study aims to investigate the behavior of soil shrinkage and water retention of biochar amended kaolin under different pore fluid salinity. A series of volumetric shrinkage and water retention tests were conducted on biochar amended kaolin in sodium chloride solution at initial concentrations of 1 %, 5 %, and 10 %. Biochar addition increased the shrinkage limit and minimum void ratio of kaolin by up to 17 % and 11 %, respectively. Air entry value of kaolin increased by 6-88 times with an increase in pore fluid salinity, caused by interparticle aggregation. Micrographs showed that biochar intrapore was filled by kaolin particles, partially hindering the interparticle aggregation of clay in the salt solution. Biochar addition lowered zeta potential on the surface of kaolin particles by 50-75 %, indicating that the immobilisation of excess sodium ions was achieved by biochar. Correspondingly, osmotic suction of pore fluid decreased by 21-64 % due to biochar's ion absorption. The findings highlighted that biochar addition to kaolin specimens minimises NaCl-induced soil shrinkage and reduces the pore fluid salinity. This study indicates that biochar could be potentially helpful for desalinisation and mitigating volumetric change issues for geo-environmental infrastructures.

Design of a 3D printed smartphone microscopic system with enhanced imaging ability for biomedical applications.

Portable, low-cost smartphone platform microscopic systems have emerged as a potential tool for imaging of various micron and submicron scale particles in recent years (Ozcan; Pirnstill and Coté; Breslauer et al.; Zhu et al.). In most of the reported works, it involves either the use of sophisticated optical set-ups along with a high-end computational tool for postprocessing of the captured images, or it requires a high-end configured smartphone to obtain enhanced imaging of the sample. Present work reports the working of a low-cost, field-portable 520× optical microscope using a smartphone. The proposed smartphone microscopic system has been designed by attaching a 3D printed compact optical set-up to the rear camera of a regular smartphone. By using cloud-based services, an image processing algorithm has been developed which can be accessed anytime through a mobile broadband network. Using this facility, the quality of the captured images can be further enhanced, thus obviating the need for dedicated computational tools for postprocessing of the images. With the designed microscopic system, an optical resolution ∼2 µm has been obtained. Upon postprocessing, the resolution of the captured images can be improved further. It is envisioned that with properly designed optical set-up in 3D printer and by developing an image processing application in the cloud, it is possible to obtain a low-cost, user-friendly, field-portable optical microscope on a regular smartphone that performs at par with that of a laboratory-grade microscope. LAY DESCRIPTION: With the ever-improving features both in hardware and software part, smartphone becomes ubiquitous in the modern civilised society with approximately 8.1 billion cell phone users across the world, and ∼40% of them can be considered as smartphones. This technology is undoubtedly the leading technology of the 21st century. Very recently, various researchers across the globe have utilised different sensing components embedded in the smartphone to convert it into a field-portable low-cost and user-friendly tool which can be used for different sensing and imaging purposes. By using simple optical components such as lens, pinhole, diffuser etc. and the camera of the smartphone, various groups have converted the phone into a microscopic imaging system. Again, by removing the camera lenses of the phone, holography images of microscopic particles by directly casting its shadows on the CMOS sensor on the phone has been demonstrated. The holographic images have subsequently been processed using the dedicated computational tool, and the original photos of the samples can be obtained. All the reported smartphone-based microscopic systems either suffer from relatively low field-of-view (FOV), resolution or it needs a high computational platform. Present work, demonstrate an alternative approach by which a reasonably good resolution (<2 µm) along with high optical magnification (520×) and a large FOV (150 µm) has been obtained on a regular smartphone. For postprocessing of the captured images an image processing algorithm has been developed in the cloud and the same can be accessed by the smartphone application, obviating the need of dedicated computational tool and a high-end configured smartphone for the proposed microscope. For the development of the proposed microscopic system, a simple optical set-up has been fabricated in a 3D printer. The set-up houses all the required optical components and the sample specimen with the 3D-printed XY stage, and it can be attached easily to the rear camera of the smartphone. Using the proposed microscopic system, enhanced imaging of USAF target and red blood cells have been successfully demonstrated. With the readily available optical components and a regular smartphone, the net cost involvement is significantly low (less than $250, including the smartphone). We envisioned that the designed system could be utilised for point-of-care diagnosis in resource-poor settings where access to the laboratory facilities is very limited.

Buccal Mucosal Graft Urethroplasty in Patients Awaiting Renal Transplantation.

OBJECTIVE: To assess the perioperative morbidity and early outcome of buccal mucosal graft (BMG) urethroplasty in patients with urethral stricture awaiting renal transplantation. METHODS: Thirteen patients awaiting renal transplantation underwent BMG urethroplasty for long anterior urethral stricture between June 2011 and March 2013. The management issues, complications, and outcome of the BMG urethroplasty in this cohort of patients were studied. RESULTS: Mean age of the patient was 38.7 ± 12.7 years. History of urethral manipulation was present in 8 patients. Mean stricture length was 6.92 ± 2.90 cm. Mean serum creatinine of the patient was 8.1 ± 3.6 mg%. Three patients required oral exploration for bleeding. Two patients had urinary extravasation, 3 patients had infected hematoma, and 1 patient developed dry gangrene of the glans. One patient had sepsis due to pyonephrosis in the postoperative period and succumbed to it. Mean follow-up of the patients was 34.54 ± 6.46 months. Three patients underwent VIU for recurrence of the stricture in the follow-up. At 3-month follow-up mean Qmax was 23.8 mL/sec, whereas at 6-month and 1-year follow-up, Qmax was 23.6 and 23.4 mL/sec, respectively. CONCLUSION: This study shows a relatively higher complication rate of urethroplasty in prerenal transplant patients. Although the number of cases is too small to arrive at any definite conclusion, this study does gives an insight into the management issues, complications, and success of urethroplasty in this group of patients.

A Brief Review on Diagnosis of Foot-and-Mouth Disease of Livestock: Conventional to Molecular Tools.

Foot-and-mouth disease (FMD) is one of the highly contagious diseases of domestic animals. Effective control of this disease needs sensitive, specific, and quick diagnostic tools at each tier of control strategy. In this paper we have outlined various diagnostic approaches from old to new generation in a nutshell. Presently FMD diagnosis is being carried out using techniques such as Virus Isolation (VI), Sandwich-ELISA (S-ELISA), Liquid-Phase Blocking ELISA (LPBE), Multiplex-PCR (m-PCR), and indirect ELISA (DIVA), and real time-PCR can be used for detection of antibody against nonstructural proteins. Nucleotide sequencing for serotyping, microarray as well as recombinant antigen-based detection, biosensor, phage display, and nucleic-acid-based diagnostic are on the way for rapid and specific detection of FMDV. Various pen side tests, namely, lateral flow, RT-LAMP, Immunostrip tests, and so forth. are also developed for detection of the virus in field condition.

Culturable microbes in shallow groundwater underlying ornithogenic soil of Cape Hallett, Antarctica.

The objective of this study was to investigate the culturable psychrotolerant microbial community in groundwater from Seabee Hook, Antarctica. Shallow groundwater can be present in coastal regions at higher latitudes during the Antarctic summer. Perched groundwater atop ice-cemented permafrost occurs on Seabee Hook, Cape Hallett, at depths from 5 to 80 cm below the soil surface. Compared with terrestrial water from other sites in Antarctica, the groundwater was high in salt and nutrients, reflecting proximity to the sea and ornithogenic soil. Microbial communities in groundwater samples from Seabee Hook exhibited aerobic metabolism of 14C-acetate at 5 degrees C. Numbers of culturable aerobic heterotrophs in the samples ranged from <10 to ca. 1 x 106 colony-forming units.mL-1, and similar numbers of microaerophiles and nitrate reducers were detected. In contrast, numbers of nitrifiers, sulfate reducers, and iron reducers were up to 1000-fold lower. All cultures were incubated at 5 degrees C. Aerobic heterotrophic bacteria isolated from the groundwater were assigned to Actinobacteria, Proteobacteria, or Bacteroidetes. The isolates were most similar to cultured bacteria from Antarctic soil or sediment and were cold, salt, and alkaline pH tolerant, indicating they are adapted to in situ conditions.

A survey of endocrine disrupting chemicals (EDCs) in municipal sewage and animal waste effluents in the Waikato region of New Zealand.

We report the results of a recent survey of the concentration of natural estrogens (17beta-estradiol, 17alpha-estradiol, estrone, estriol) and the synthetic estrogen, 17alpha-ethynylestradiol in representative animal wastes and sewage treatment plant (STP) effluents in the Waikato region of New Zealand. Dairy farm effluent samples showed high levels of estradiol (19-1360 ng/L) and its breakdown product estrone (41-3123 ng/L) compared with piggery or goat farm effluents. The combined load for these estrogens (excluding beta epimer) varied from 60 to >4000 ng/L. The piggery effluent provided the lowest total estrogen load (46 ng/L), with estrone accounting for nearly 60% of the measured estrogens in this sample. The synthetic analogue, 17alpha-ethynylestradiol was detected only in one wastewater treatment plant sample, albeit at trace level. An estrogen receptor competitive binding assay was used to test the biological activity of the samples and confirmed that most agricultural waste samples contain high levels of estrogenic compounds. The potential of these wastes to cause endocrine disruption in the receiving ecosystem is unknown at present.

Simultaneous analysis of triasulfuron, metsulfuron-methyl and chlorsulfuron in water and alkaline soils by high-performance liquid chromatography.

A method capable of simultaneously detecting residues of three sulfonylurea herbicides at microgram/l and microgram/kg level in water and alkaline soils has been described. The method is based on solid phase extraction and HPLC with UV detection. In alkaline soils especially those containing low organic carbon it was possible to extract the herbicides with de-ionised water and no clean up step was needed. Soil samples spiked with technical grade triasulfuron, metsulfuron-methyl and chlorsulfuron were extracted twice by shaking with de-ionised water for one hour and centrifuging at 10,000 rpm for 15 minutes. Supernatants filtered through glass micro-fibre filters were passed through C18 cartridges previously pre-conditioned with methanol and de-ionised water at a flow rate of < 20 ml/min. Residues of the herbicides retained on the cartridge were eluted with acidified methanol. The eluate was analysed by HPLC. A C18 column was used with a mobile phase of methanol/water (40 + 60, V/V for for the herbicide residues were 1.0 microgram/l and 3 micrograms/kg in water and soil, respectively. The average recoveries for water samples ranged from 73-94%, while for soil samples recoveries were 77-97% for the three compounds studied.

Late diagnosis of cryptorchidism: a failure of medical screening?

A retrospective review of hospital and available community records of 47 children undergoing orchidopexy in a district hospital was undertaken to determine adequacy of screening for cryptorchidism and factors associated with late referral. Twenty eight of these boys were previously examined on 108 occasions. Diagnosis was missed on 32 occasions and the record of 38 clinical examinations did not include position of testes. In the case of 16 boys (four under school age and 12 of school age) appropriate action was not taken once the diagnosis was made. Diagnosis was reliably made in school aged children but in children under the age of 1 year cryptorchidism was frequently missed by the examining doctor. It is suggested that criteria for diagnosis and referral should be agreed in any surveillance programme. Junior doctors in hospital responsible for routine clinical examination of children during admission and clinical medical officers or general practitioners during routine clinical examination of boys should be clearly instructed to examine and record the position of the testes.