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Spring pump

Tip W Loo, David M Clarke
P-glycoprotein (P-gp) is an ABC (ATP-Binding Cassette) drug pump that is clinically important because it confers multidrug resistance. Drugs bind at the interface between the transmembrane domains to activate ATPase activity at the two nucleotide-binding domains (NBDs). Drug transport involves ATP-dependent conformational changes between inward- (open, NBDs far apart) and outward-facing (closed, NBDs close together) conformations. Recently, it was reported that the conserved glutamines residues (Gln475 in NBD1 and Gln1118 in NBD2) in the Q loops of P-gp when mutated to alanine completely inhibited the drug-stimulated ATPase activity...
December 23, 2016: Biochemical and Biophysical Research Communications
Kun-Mou Li, Craig Wilkinson, Juho Kellosalo, Jia-Yin Tsai, Tommi Kajander, Lars J C Jeuken, Yuh-Ju Sun, Adrian Goldman
Membrane-bound pyrophosphatases (M-PPases), which couple proton/sodium ion transport to pyrophosphate synthesis/hydrolysis, are important in abiotic stress resistance and in the infectivity of protozoan parasites. Here, three M-PPase structures in different catalytic states show that closure of the substrate-binding pocket by helices 5-6 affects helix 13 in the dimer interface and causes helix 12 to move down. This springs a 'molecular mousetrap', repositioning a conserved aspartate and activating the nucleophilic water...
December 6, 2016: Nature Communications
Robinjeet Singh, Garrett D Cole, Jonathan Cripe, Thomas Corbitt
We report a stable double optical spring effect in an optical cavity pumped with a single optical field that arises as a result of birefringence. One end of the cavity is formed by a multilayer Al_{0.92}Ga_{0.08}As/GaAs stack supported by a microfabricated cantilever with a natural mode frequency of 274 Hz. The optical spring shifts the resonance to 21 kHz, corresponding to a suppression of low frequency vibrations by a factor of about 5 000. The stable nature of the optical trap allows the cavity to be operated without any external feedback and with only a single optical field incident...
November 18, 2016: Physical Review Letters
C S Ball, R F Renzi, A Priye, R J Meagher
Check valves are often essential components in microfluidic devices, enabling automated sample processing for diagnostics at the point of care. However, there is an unmet need for a check valve design that is compatible with rigid thermoplastic devices during all stages of development-from initial prototyping with a laser cutter to final production with injection molding. Here, we present simple designs for a passive, normally closed check valve that is manufactured from commonly available materials with a CO2 laser and readily integrated into prototype and production thermoplastic devices...
November 1, 2016: Lab on a Chip
R Botha, R T Newman, P P Maleka
Radon activity concentrations (in water and in air) were measured at 13 selected locations at the Avalon Springs thermal spa resort in Montagu (Western Cape, South Africa) to estimate the associated effective dose received by employees and visitors. A RAD-7 detector (DURRIDGE), based on alpha spectrometry, and electret detectors (E-PERM®Radelec) were used for these radon measurements. The primary source of radon was natural thermal waters from the hot spring, which were pumped to various locations on the resort, and consequently a range of radon in-water analyses were performed...
September 2016: Health Physics
Giovanna De Filippis, Laura Foglia, Mauro Giudici, Steffen Mehl, Stefano Margiotta, Sergio Luigi Negri
Mediterranean areas are characterized by complex hydrogeological systems, where management of freshwater resources, mostly stored in karstic, coastal aquifers, is necessary and requires the application of numerical tools to detect and prevent deterioration of groundwater, mostly caused by overexploitation. In the Taranto area (southern Italy), the deep, karstic aquifer is the only source of freshwater and satisfies the main human activities. Preserving quantity and quality of this system through management policies is so necessary and such task can be addressed through modeling tools which take into account human impacts and the effects of climate changes...
December 15, 2016: Science of the Total Environment
Larry A Fox, Emilie Balkman, Kim Englert, Jobayer Hossain, Nelly Mauras
BACKGROUND: This study explored the safety of using real-time sensor glucose (SG) data for treatment decisions in adolescents with poorly controlled type 1 diabetes. METHODS: Ten adolescents with type 1 diabetes, HbA1c ≥9% on insulin pumps were admitted to the clinical research center and a continuous glucose sensor was inserted. Plasma glucose was measured at least hourly using Yellow Springs Instrument's (YSI) glucose analyzer. Starting at dinner, SG rather than YSI was used for treatment decisions unless YSI was <70 mg/dL (<3...
July 20, 2016: Pediatric Diabetes
Alexa Juarez, Kelley Maynard, Erica Skerrett, Elizabeth Molyneux, Rebecca Richards-Kortum, Queen Dube, Z Maria Oden
This article describes the design and evaluation of AutoSyP, a low-cost, low-power syringe pump intended to deliver intravenous (IV) infusions in low-resource hospitals. A constant-force spring within the device provides mechanical energy to depress the syringe plunger. As a result, the device can run on rechargeable battery power for 66 hours, a critical feature for low-resource settings where the power grid may be unreliable. The device is designed to be used with 5- to 60-mL syringes and can deliver fluids at flow rates ranging from 3 to 60 mL/hour...
July 5, 2016: American Journal of Tropical Medicine and Hygiene
Lisa K Volkening, Kaitlin C Gaffney, Michelle L Katz, Lori M Laffel
BACKGROUND: The purpose was to identify patient/family characteristics and recruitment process characteristics associated with the decision to participate in a 2-year continuous glucose monitoring (CGM) RCT for youth with type 1 diabetes and their families. METHOD: Study staff approached patients who were conditionally eligible according to medical record review or referred by a provider. We categorized families according to participation decision (agree vs decline) and timing of decision (day of approach vs later ["thinkers"])...
June 22, 2016: Journal of Diabetes Science and Technology
Eliapenda Elisante, Alfred N N Muzuka
The quality of the groundwater along the slopes of Mount Meru, Tanzania, is poorly understood. Water access and sanitation practices may pose health risks to communities. This study was undertaken to assess the sources, abundance and seasonal variation of coliform bacteria in groundwater and factors contributing to such variations along slopes of Mount Meru, Tanzania. Water samples collected from 67 randomly selected water sources (springs, shallow wells which ranged from 4 to 35 m deep and Boreholes above 40 m deep) during dry and wet seasons were analysed for total coliform (TC), faecal coliform (FC), Escherichia coli (E...
December 0: Environmental Monitoring and Assessment
Javed Nawab, Sardar Khan, Sharafat Ali, Hassan Sher, Ziaur Rahman, Kifayatullah Khan, Jianfeng Tang, Aziz Ahmad
Human beings are frequently exposed to pathogens and heavy metals through ingestion of contaminated drinking water throughout the world particularly in developing countries. The present study aimed to assess the quality of water used for drinking purposes in Malakand Agency, Pakistan. Water samples were collected from different sources (dug wells, bore wells, tube wells, springs, and hand pumps) and analyzed for different physico-chemical parameters and bacterial pathogens (fecal coliform bacteria) using standard methods, while heavy metals were analyzed using atomic absorption spectrophotometry (AAS-PEA-700)...
May 2016: Environmental Monitoring and Assessment
Daniel Marcos Bonotto
This paper describes the natural radioactivity due to (238)U and (234)U in 75 water sources from spas located in 14 municipalities in São Paulo and Minas Gerais states, Brazil. These waters are extensively utilized for drinking in public places, bottling and bathing purposes, among other uses. The water samples were taken from springs and pumped tubular wells drilled into different aquifer systems in the Paraná and Southeastern Shield hydrogeological provinces. The measurements of alpha-emitting radionuclides were also accompanied by the monitoring of temperature, pH, Eh, electrical conductivity, dissolved gases (O2, CO2, H2S, radon, thoron) and major constituents...
January 2017: Journal of Environmental Radioactivity
Katharina Michael, Nils Koschnick, Hans-O Pörtner, Magnus Lucassen
The maintenance of ion and pH homeostasis despite changes in ambient temperature is crucial for ectothermic organisms. Thermal sensitivity of Na(+)/K(+) ATPase mRNA expression, protein expression and activity was determined in gills of North Sea cod (NC) and Northeastern Arctic cod (NEAC), acclimated for 6 weeks at 4 and 10 °C and compared to field samples of North Sea cod (sNC), acclimatized to early spring (4 °C) and summer (18 °C) conditions. The same analyses were conducted in gills of the confamiliar whiting, acclimated at 4 and 10 °C...
May 2016: Journal of Comparative Physiology. B, Biochemical, Systemic, and Environmental Physiology
Gholamali Jafari, Brian M Wasko, Ashley Tonge, Nathan Schurman, Cindy Dong, Zhongyu Li, Rebecca Peters, Ernst-Bernhard Kayser, Jason N Pitt, Phil G Morgan, Margaret M Sedensky, Antony R Crofts, Matt Kaeberlein
Mitochondria play an important role in numerous diseases as well as normative aging. Severe reduction in mitochondrial function contributes to childhood disorders such as Leigh Syndrome, whereas mild disruption can extend the lifespan of model organisms. The Caenorhabditis elegans isp-1 gene encodes the Rieske iron-sulfur protein subunit of cytochrome c oxidoreductase (complex III of the electron transport chain). The partial loss of function allele, isp-1(qm150), leads to several pleiotropic phenotypes. To better understand the molecular mechanisms of ISP-1 function, we sought to identify genetic suppressors of the delayed development of isp-1(qm150) animals...
November 10, 2015: Proceedings of the National Academy of Sciences of the United States of America
Guorong Wang, Lin Zhong, Xia He, Zhongqing Lei, Gang Hu, Rong Li, Yunhai Wang
The influence of spring stiffness and valve quality on the motion behaviors of reciprocating plunger pump discharge valves was investigated by fluid structure interaction (FSI) simulation and experimental analysis. The mathematical model of the discharge valve motion of a 2000-fracturing pump was developed and the discrete differential equations were solved according to FSI and results obtained by ANDINA software. Results indicate that spring stiffness influences the maximum lift, the opening resistance and shut-off lag angle, as well as the fluid velocity of the clearance, the impact stress and the volume efficiency of the pump valve in relation to the valve quality...
2015: PloS One
Muammar Mansor, Trinity L Hamilton, Matthew S Fantle, Jennifer L Macalady
Large, sulfur-cycling, calcite-precipitating bacteria in the genus Achromatium represent a significant proportion of bacterial communities near sediment-water interfaces at sites throughout the world. Our understanding of their potentially crucial roles in calcium, carbon, sulfur, nitrogen, and iron cycling is limited because they have not been cultured or sequenced using environmental genomics approaches to date. We utilized single-cell genomic sequencing to obtain one incomplete and two nearly complete draft genomes for Achromatium collected at Warm Mineral Springs (WMS), FL...
2015: Frontiers in Microbiology
L E Zuffianò, A Basso, D Casarano, V Dragone, P P Limoni, A Romanazzi, F Santaloia, M Polemio
The Mar Piccolo basin is an internal sea basin located along the Ionian coast (Southern Italy), and it is surrounded primarily by fractured carbonate karstic environment. Because of the karstic features, the main continental water inflow is from groundwater discharge. The Mar Piccolo basin represents a peculiar and sensitive environment and a social emergency because of sea water and sediment pollution. This pollution appears to be caused by the overlapping effects of dangerous anthropogenic activities, including heavy industries and commercial and navy dockyards...
July 2016: Environmental Science and Pollution Research International
Xosé Anxelu G Morán, Laura Alonso-Sáez, Enrique Nogueira, Hugh W Ducklow, Natalia González, Ángel López-Urrutia, Laura Díaz-Pérez, Alejandra Calvo-Díaz, Nestor Arandia-Gorostidi, Tamara M Huete-Stauffer
Heterotrophic bacteria play a major role in organic matter cycling in the ocean. Although the high abundances and relatively fast growth rates of coastal surface bacterioplankton make them suitable sentinels of global change, past analyses have largely overlooked this functional group. Here, time series analysis of a decade of monthly observations in temperate Atlantic coastal waters revealed strong seasonal patterns in the abundance, size and biomass of the ubiquitous flow-cytometric groups of low (LNA) and high nucleic acid (HNA) content bacteria...
July 7, 2015: Proceedings. Biological Sciences
S J Chen, N Ji, Y-x Chen, S-j Zhao, J-r Xiao, X-m Lin, X-x Han
Cervical necrotising fasciitis is a progressive deep infection of the neck associated with high mortality, and skillful management of the airway is critical for operations under general anaesthesia. Tracheostomy under local anaesthesia has been considered the gold standard of airway management in patients with deep neck infections, but it may be difficult or impossible in advanced cases. We report here our experience over 6 years (January 2008 and December 2013) during which a total of 15 patients was diagnosed with cervical necrotising fasciitis...
September 2015: British Journal of Oral & Maxillofacial Surgery
Klaus Zweckberger, Yang Liu, Jian Wang, Nicole Forgione, Michael G Fehlings
Spinal cord injuries (SCI) cause serious neurological impairment and psychological, economic, and social consequences for patients and their families. Clinically, more than 50% of SCI affect the cervical spine. As a consequence of the primary injury, a cascade of secondary mechanisms including inflammation, apoptosis, and demyelination occur finally leading to tissue scarring and development of intramedullary cavities. Both represent physical and chemical barriers to cell transplantation, integration, and regeneration...
2015: Journal of Visualized Experiments: JoVE
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