Trollelyng3972
Lowpermeability zone (LPZ) can play an important role as a sink or secondary source in contaminant transport in groundwater system. This study investigated the rate and end product of nitrate bioreduction in LPZ sediments. The sedimentswere fromthe U.S. Department of Energy's Hanford Site,where nitrate is a groundwater contaminant as a by-product of radionuclide waste discharges. The LPZ at the Hanford site consists of two layerswith an oxidized layer on top and reduced layer below. The oxidized layer is directly in contact with the overlying contaminated aquifer, while the reduced layer is in contact with an uncontaminated aquifer below. The experimental results showed that nitrate bioreduction rate and end-product differed significantly in the sediments. The bioreduction rate in the oxidized sediment was significantly faster than that in the reduced one. A significant amount of N2O was accumulated in the reduced sediment; while in the oxidized sediment, N2O was further reduced to N2. selleck kinase inhibitor RT-PCR analysis revealed that nosZ, the gene that codes for N2O reductase, was below detection limit in the reduced sediment. Batch experiments and kinetic modeling were performed to provide insights into the role of organic carbon bioavailability, biomass growth, and competition between nitrate and its reducing products for electrons fromelectron donors. The results revealed that it is important to consider sediment redox conditions and functional genes in understanding and modeling nitrate bioreduction in subsurface sediments. The results also implied that LPZ sediments can be important sink of nitrate and a potential secondary source of N2O as a nitrate bioreduction product in groundwater.Increasing demands for freshwater make it necessary to find innovative ways to extend the life of our water resources, and to manage them in a sustainable way. Indirect water reuse plays a role in meeting freshwater demands but there is limited documentation of it. There is a need to analyze its current status for water resources planning and conservation, and for understanding how it potentially impacts human health. However, the fact that data are archived in discrete uncoordinated databases by different state and federal entities, limits the capacity to complete holistic analysis of critical resources at large watershed scales. Humans alter the water cycle for food production, manufacturing, energy production, provision of potable water and recreation. Ecosystems services are affected at watershed scales but there are also global scale impacts from greenhouse gas emissions enabled by access to cooling, processing and irrigation water. To better document these issues and to demonstrate the utility of such an analysis, we studied the Wabash River Watershed located in the U.S. Midwest. Data for water extraction, use, discharge, and river flow were collected, curated and reorganized in order to characterize the water use and reuse within the basin. Indirect water reuse was estimated by comparing treated wastewater discharges with stream flows at selected points within the watershed. Results show that during the low flow months of July-October, wastewater discharges into the Wabash River basin contributed 82 to 121% of the stream flow, demonstrating that the level of water use and unplanned reuse is significant. These results suggest that intentional water reuse for consumptive purposes such as landscape or agricultural irrigation could have substantial ecological impacts by diminishing stream flow during vulnerable low flow periods.This study provides quantitative information on the aggregation and dissolution behaviour of silver nanoparticles (AgNPs) upon discharge in fresh and sea waters, represented here as NaCl solutions of increasing ionic strength (up to 1M) and natural fjord waters. Natural polysaccharides, sodium alginate (ALG) and gum Arabic (GA), were used as coatings to stabilize the AgNPs and the compounds acted as models to study AgNP aggregation kinetics. The DLVO theory was used to quantitatively describe the interactions between the AgNPs. The stability of AgNPs was established using UV-Visible spectrophotometry, including unique information collected during the first seconds of the aggregaton process. Alginate coating resulted in a moderate stabilization of AgNPs in terms of critical coagulation concentration (~82mM NaCl) and a low dissolution of less then 10% total Ag in NaCl solutions up to 1M. Gum Arabic coated AgNPs were more strongly stabilized, with ~7-30% size increase up to 77mM NaCl, but only when the silver ion content initially present in solution was low ( less then 10% total Ag). The ALG and GA coated AgNPs showed a strongly enhanced stability in natural fjord waters (ca. 5h required to reduce the area of the surface plasmon resonance band (SPRB) by two fold) compared with NaCl at an equivalent ionic strength (1-2min period for a two fold SPRB reduction). This is ascribed to a stabilizing effect from dissolved organic matter present in natural fjord waters. Interestingly, for AgNP-GA solutions with 40% of total silver present as unreacted silver ions in the NP stock solution, fast aggregation kinetics were observed in NaCl solutions (SPRB area was reduced by ca. 50% within 40-150min), with even more rapid removal in fjord waters, attributed to the high amount of silver-chloride charged species, that interact with the NP coating and/or organic matter and reduce the NPs stabilization.
To evaluate assisted reproductive technology (ART) outcomes using testicular sperm in oligospermic men who previously failed to achieve paternity using TUNEL-positive ejaculated sperm.
Retrospective cohort.
Academic medical center.
Twenty-four oligospermic men who failed one or more ART cycles using ejaculated sperm with TUNEL-positive proportion >7%, and subsequently underwent microsurgical testicular sperm extraction (TESE).
TESE followed by intracytoplasmic sperm injection (ICSI).
TUNEL-positive level in ejaculated and testicular sperm; clinical pregnancy.
The mean TUNEL-positive level was 24.5% for ejaculated sperm, and 4.6% for testicular sperm. Clinical pregnancy was achieved in the first ART cycle with testicular sperm in 12 (50%) out of 24 couples. There was no statistically significant difference in maternal and paternal age, maternal gravity and parity, number of previous ART attempts, concentration or motility of retrieved sperm, number of oocytes retrieved, fertilization rate, or jaculated sperm. No other clinical predictors of successful pregnancies after the use of surgically retrieved sperm could be identified. In men with elevated TUNEL-positive ejaculated sperm and failed ART, TESE may be considered.This statement explores the ethical considerations surrounding the provision of fertility services to transgender individuals and concludes that denial of access to fertility services is not justified.Pain is the most evident clinical manifestation of deep infiltrating endometriosis (DIE). Several hormonal and immunologic mechanisms are markedly altered in DIE compared with superficial peritoneal and ovarian endometriosis, and may explain its most aggressive behavior and the presence of severe pain symptoms. Hormonal therapies, such as combined hormonal contraceptives and progestogens, should be regarded as first-line treatment, as they are efficacious, safe, and well tolerated. Gonadotropin-releasing hormone agonists may be used in patients with symptoms persisting after the administration of first-line therapies. Scanty literature is available for danazol treatment in patients with DIE and, however, it has become less popular due to the high rates of androgenic adverse events (AEs). The partial relief of pain that often is achieved with available therapies and its recurrence after the suspension of the treatment have brought to the development of new therapies (such as aromatase inhibitors, oral GnRH antagonists) that are currently under investigation. Surgical excision of DIE should be considered in patients with pain symptoms persisting after first-line hormonal therapies. The benefits of surgery in terms of pain improvement should be always balanced with the risk of intraoperative complications and for this reason surgical cases should be referred to tertiary centers for the treatment of DIE. A multidisciplinary approach is mandatory in patients with DIE involving the bowel and/or the urinary tract.
To create a rapid, inexpensive, efficient, and reproducible real-time three-dimensional (3-D) analysis of viable spermatozoa. Previous studies have demonstrated that abnormal semen profiles are associated with a modest increase in the frequency of sperm chromosomal abnormalities, and that sperm with aberrations in the shape and contours of the head may be carriers of chromatinic defects. Although high-power magnification and enhanced video-generated magnification have been suggested, these techniques are inherently limited by the clarity of the image, the time required for the analysis, and the risk of variable head-positioning during imaging.
In vitro experiment.
University-affiliated infertility research laboratory.
Anonymous sperm donors.
Individual motile sperm were identified, analyzed at ×600 magnification, and a 10-second digital video was obtained.
Image-tracking software captured serial photographs of sperm from recorded videos. Images were automatically extracted from each video frame using enhanced correlation coefficient maximization; the general shape of the sperm was extracted via space-carving. The reconstructed image was rotated to permit viewing from any direction, and the final image was rendered through interpolation.
This technique yielded images that enable noninvasive, 3-D, real-time, in vitro assessment of sperm surface morphology.
This proof-of-principle demonstrates that by keeping spermatozoa in a fluid environment, a 3-D sperm-surface reconstruction can be created. This technique can be automated, requires minimal computing power, and utilizes equipment already available in most embryology laboratories.
This proof-of-principle demonstrates that by keeping spermatozoa in a fluid environment, a 3-D sperm-surface reconstruction can be created. This technique can be automated, requires minimal computing power, and utilizes equipment already available in most embryology laboratories.
To answer the questions Are perinatal reproductive hormone profiles different in case of a twin compared with a singleton pregnancy? Are reproductive endocrine profiles of twin girls influenced by their male co-twin and vice versa?
Prospective cohort study from January 2004 to October 2009.
Not applicable.
A total of 204 mothers of twins and 248 singleton control subjects, aged >18 years, pregnant with a twin or singleton and no endocrine disease or malignancy.
Blood samples were collected at mid-gestation from the mother and at delivery from the mothers and the umbilical cords. Estrogens, androgens, sex hormone-binding globulin, progesterone, and gonadotropins were measured.
Hormonal profiles were compared between singletons and twins, different types of twins, and opposite-sex and same-sex twins.
Estrogen and progesterone concentrations were higher in mothers of twins compared with singletons, but twin babies had lower estrogen and progesterone concentrations at birth. Opposite-sex twin girls did not have higher androgens in cord blood compared with same-sex twin girls.