Gradient Corporation

Cambridge, MA, United States

Gradient Corporation

Cambridge, MA, United States
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Turn on the faucet and it is likely that clean, drinkable water will come out; water that can be safely consumed. However, one in four cities around the world are water-stressed, and almost 97 percent of the Earth’s water is undrinkable. From the water crisis in Flint, Michigan, to droughts across the country, the significance of water utility and sustainability is more prevalent than ever before. To address the future of the water utilities, academics, entrepreneurs, business leaders, and thought leaders came together to discuss the future of water in the United States and around the world at the fifth annual MIT Water Summit on Nov. 17 and 18, hosted by the MIT Water Club. Members of the MIT Water Club moderated five panels over the two-day summit. This year’s topics ranged from the role of policy and economics on the future of water to the influence of industry and academic advances, but the overall vision was toward the future. “My aim was to hold an event with a broad enough appeal, but a specific focus explored through different approaches, such as technology, finance and policy,” said Gualtiero Jaeger, director of the MIT Water Summit and PhD candidate in the MIT- Woods Hole Oceanographic Institution (WHOI) Joint Program. “The theme ‘water utilities of the future’ gradually developed out of our initial ideas, and we looked for speakers with relevant expertise. Here our alumni and other connections helped us immensely.” “Creativity is part of the daily DNA of the water industry,” said keynote speaker George Hawkins, CEO and general manager of DC Water. Hawkins noted that many solutions to water problems require thinking outside the box, and cited the modernization and re-branding of DC Water to increase public awareness of their water utility. Similar creativity emerged through the interdisciplinary discussions at the MIT Water Summit. Luis Montestruque, president and CEO of EmNet, suggested the possible overlaps between green energy and water systems. Noting the use of solar energy to power electronic street signs, he questioned whether water utilities could follow to lower the energy costs. Stephen Estes-Smargiassi '79, director of planning and sustainability at Massachusetts Water Resources Authority (MWRA) and an alumnus of the MIT Department of Civil and Environmental Engineering (CEE), served as a keynote speaker and gave the Massachusetts perspective of water and energy. In his talk, Estes-Smargiassi highlighted the significance of water as an energy source, pointing out that 31 percent of the energy needed by MWRA is renewable energy, meaning the amount of money spent purchasing energy and power has decreased. By recycling water, Massachusetts is simultaneously creating energy. Ed McCormick, president of McCormick Strategic Water Management, cited potable reuse as one major example of creativity in the water sector during the panel on the role of economics. Potable reuse is the use of technologies to treat wastewater without putting water back into the environment and through the water cycle. McCormick acknowledged the negative perceptions people have of associating human waste with drinking water. “We replicate the water cycle with technology; we can do as good a job as nature. Those negative perceptions are changing and that’s where I see the creativity coming big time. It hasn’t quite swept to areas where you have more water than you need, but it’s certainly happening in the Southwest,” he said. Professor Gabriella Carolini of the MIT Department of Urban Studies and Planning suggested that there is no shortage of technological innovation, but that technological implementation is the major issue in the water sector. “Implementation is a problem that is not just financial, regulatory, technological or social; it’s a combination of all of those things, so we need to look at the implementation issue,” she said. Current policies and regulations are also not always conducive to rapid execution of news ideas. One component to this issue is the extensive pilot period, when technologies and ideas are studied before used widely. “We pilot for so long that by the time you actually determine that something is effective, there’s a new technology that we want to pilot. What we want to do is release some of the regulations a little bit so that we can promote some of these innovative technologies that are out there” said Mary Barry, executive director of New England Water Environment Association (NEWEA). Instead of hindering creative ideas with regulations and pilot programs, “We should be promoting innovation. That’s the only way we are going to grow and the only way we’re going to make things more efficient, both on the energy side and on the financial side,” she said. The creation of innovative technologies and their aligning with regulatory standards are only worth so much until the general public is on board with their implementation. As Ed McCormick suggested, changing the public’s perception of an issue of new innovative solutions is critical to the success of the product and the water sector. Communicating with the public to implement new ideas and technologies Speakers noted that reaching the general public is a difficult task, especially with the wide variety of media outlets and fragmented audiences. “I think the media can be a great asset to us as an industry, I just don’t think water is their focus,” said Mary Barry of NEWEA. One way to reach adults is through their children, who often talk about what they learn with their parents at home, she highlighted, citing the effectiveness of marketing to children. “Talking to students in schools allows them to go home and talk with their parents about something their parents might not be thinking about, because it has always been a luxury for them to have clean water and sanitation,” Barry said. The media is still considered a valuable method, however: “The full spectrum of media is an extremely useful tool, for even controlling outstanding systems like our own. I would say that the situation in Flint is an experience that is super important. It’s one thing to say that we have achieved amazing results in drinking water in this country, but I might suggest that we are only as good as our weakest link, and if something like that can happen in Flint, then it can happen anyplace,” said Carolini. Communication takes many forms beyond the media as well, such as through access to data. The availability and transparency of data in the water sector was a theme that continued throughout the Water Summit. During the panel “Visions for the Future,” panelists discussed the presence of smart systems, and the observation of resulting consumer behavior changes. Professor James Wescoat of the Department of Architecture and the MIT Tata Center spoke of staying in a hotel in Europe that displayed water meters in each room and showed how much water was used when a visitor turned on the shower or the sink. He recalled hearing fellow travelers discuss how few liters of water they used, each wanting to be lower than his counterpart. On that note, George Hawkins pointed out that when DC Water installed automatic meter readings in 2002, they noticed drops in water use. DC Water noted similar decreases when they began sending high-use notification alerts to customers, courtesy messages notifying customers of significant changes in water use, which could indicate leaking pipes. Alexander Heil, chief economist of the Port Authority of New York and New Jersey, made a similar point about water usage during the panel on the role of economics, noting that without smart systems and up-to-date information of one’s water usage, there is a disconnect between how people pay for water and how they use it. “There is a discrepancy between the point of usage and the point of payment. For example, if you have a quarterly billing cycle, nobody remembers how they used water three months ago.” The availability of data at water utility plants is crucial for the plants to troubleshoot any issues with their product. Anupam Bhargava, vice president of advanced technology and innovation at Xylem Inc., discussed this importance through disruptive sensing capabilities, one of the areas Xylam is looking into for the future. Disruptive sensing capabilities would allow water utility plants to detect issues immediately and allow them to be proactive in finding a solution. Noting that water, unlike other products commonly sold, cannot be recalled once it leaves the plant, Bhargava said that “real-time sensing capability is going to allow our customers to operate and manage their plants a lot more productively and safely.” Disruptive sensing capabilities would thus allow water utility plants to have important information at their fingertips and to avoid major public health hazards. Collaborating to solve major issues in the water sector Collaboration is often seen in the water sector to address major issues and find solutions. However, collaboration does not always mean centralized ownership. George Hawkins of DC Water mentioned the challenges of creating a centralized water system, because smaller municipalities prefer to maintain ownership of localized water sources. Instead, he proposed the creation of a more coordinated system on a broader scale, rather than centralized ownership. Ed McCormick shared that he has started to see such coordination through regional partnerships between smaller utilities. “In the San Francisco Bay Area, there are nearly 60 utilities that all discharge in the San Francisco Bay, some of them are very small and others are very large. What we have seen are agreements where small utilities can connect with other utilities to purchase bulk chemicals and get the benefit of scale, that larger utilities can get,” McCormick said. Marcus Gay, executive director of New England Water Innovation Network, pointed out that “innovation isn’t just about new technological solutions, it’s about bringing both innovative technological solutions and market adoption together. It’s an entire process.” One way to do this is to foster collaboration between academia and the water industry markets, to create a well-researched product or plan to implement and have a real-world impact. This was brought to life by the Water Summit’s panel on “Academia to Markets.” John Lienhard V, professor in the MIT Department of Mechanical Engineering and director of the Abdul Latif Jameel World Water and Food Security Lab, noted that the best partnerships are with people who understand the need for water. “We have worked with a number of international institutions from countries that have serious water challenges. We have tried to get into these issues with them because they understand that these are not simply academic problems, but they are problems that can be translated back into the needs of their countries and societies in a way that provides water to people’s taps, that help people actually live and survive. In those cases, we have seen that the research is productive, it is viewed as important, it is supported well and it has the impact we need in both the practical and academic side,” he said. The fifth annual Water Summit was a full house, complete with academics from MIT and neighboring schools, business leaders, thought leaders, and students. Sami Harper, a graduate student in CEE, attended the summit to find out more about how changing technology is affecting the way we get our water. “I learned a lot from the keynote addresses which shed some light on water utility operations and the future of the industry,” she said. Members of the MIT Water Club also benefited from the event. “The interactions with professionals beyond our academic research was immensely valuable. We received insight into the water industry and the workings of institutions and companies in the water world,” Gualtiero Jaeger said. Sponsors for this year's Water Summit included Desalitech, Gradient Corporation, Abdul Latif Jameel World Water and Food Security Lab, the MIT Department of Civil and Environmental Engineering, Massachusetts Clean Energy Center, New England Water Innovation Network, Pepsico, Woods Hole Oceanographic Institution, and Xylem.


Zanetti K.A.,U.S. National Cancer Institute | Zanetti K.A.,Epidemiology and Genomics Research Program | Haznadar M.,U.S. National Cancer Institute | Welsh J.A.,U.S. National Cancer Institute | And 10 more authors.
Cancer Research | Year: 2012

Because chronic intestinal inflammation is a risk factor for colorectal cancer, we hypothesized that genetic variants of inflammatory mediators, such as mannose-binding lectin 2 (MBL2), are associated with colon cancer susceptibility. Here, we report the association of 24 MBL2 single-nucleotide polymorphisms (SNP) and corresponding haplotypes with colon cancer risk in a case-control study. Four SNPs in the 3′-untranslated region (UTR) of the gene (rs10082466, rs2120132, rs2099902, and rs10450310) were associated with an increased risk of colon cancer in African Americans. ORs for homozygous variants versus wild-type ranged from 3.17 [95% confidence interval (CI), 1.57-6.40] to 4.51 (95% CI, 1.94-10.50), whereas the 3′-UTR region haplotype consisting of these four variants had an OR of 2.10 (95% CI, 1.42-3.12). The C allele of rs10082466 exhibited a binding affinity of miR-27a and this allele was associated with both lower MBL plasma levels and activity. We found that 50 secretor haplotypes known to correlate with moderate and low MBL serum levels exhibited associations with increased risk of colon cancer in African Americans, specifically as driven by two haplotypes, LYPA and LYQC, relative to the referent HYPA haplotype (LYPA: OR, 2.60; 95% CI, 1.33-5.08 and LYQC: OR, 2.28; 95% CI, 1.20-4.30). Similar associations were not observed in Caucasians. Together, our results support the hypothesis that genetic variations in MBL2 increase colon cancer susceptibility in African Americans. ©2012 AACR.


Glynn S.A.,U.S. National Cancer Institute | Glynn S.A.,U.S. National Institutes of Health | Prueitt R.L.,U.S. National Cancer Institute | Ridnour L.A.,U.S. National Institutes of Health | And 7 more authors.
BMC Cancer | Year: 2010

Background: Inducible cyclooxgenase-2 (COX-2) is commonly overexpressed in breast tumors and is a target for cancer therapy. Here, we studied the association of COX-2 with breast cancer survival and how this association is influenced by tumor estrogen and HER2 receptor status and Akt pathway activation.Methods: Tumor COX-2, HER2 and estrogen receptor α (ER) expression and phosphorylation of Akt, BAD, and caspase-9 were analyzed immunohistochemically in 248 cases of breast cancer. Spearman's correlation and multivariable logistic regression analyses were used to examine the relationship between COX-2 and tumor characteristics. Kaplan-Meier survival and multivariable Cox proportional hazards regression analyses were used to examine the relationship between COX-2 and disease-specific survival.Results: COX-2 was significantly associated with breast cancer outcome in ER-negative [Hazard ratio (HR) = 2.72; 95% confidence interval (CI), 1.36-5.41; comparing high versus low COX-2] and HER2 overexpressing breast cancer (HR = 2.84; 95% CI, 1.07-7.52). However, the hazard of poor survival associated with increased COX-2 was highest among patients who were both ER-negative and HER2-positive (HR = 5.95; 95% CI, 1.01-34.9). Notably, COX-2 expression in the ER-negative and HER2-positive tumors correlated significantly with increased phosphorylation of Akt and of the two Akt targets, BAD at Ser136 and caspase-9 at Ser196.Conclusions: Up-regulation of COX-2 in ER-negative and HER2-positive breast tumors is associated with Akt pathway activation and is a marker of poor outcome. The findings suggest that COX-2-specific inhibitors and inhibitors of the Akt pathway may act synergistically as anticancer drugs in the ER-negative and HER2-positive breast cancer subtype. © 2010 Glynn et al; licensee BioMed Central Ltd.


Kerper L.E.,Gradient Corporation | Lynch H.N.,Gradient Corporation | Zu K.,Gradient Corporation | Tao G.,Gradient Corporation | And 2 more authors.
Inhalation Toxicology | Year: 2015

Context: US EPA proposed a Reference Concentration for Libby amphibole asbestos based on the premise that pleural plaques are adverse and cause lung function deficits. Objective: We conducted a systematic review to evaluate whether there is an association between pleural plaques and lung function and ascertain whether results were dependent on the method used to identify plaques. Methods: Using the PubMed database, we identified studies that evaluated pleural plaques and lung function. We assessed each study for quality, then integrated evidence and assessed associations based on the Bradford Hill guidelines. We also compared the results of HRCT studies to those of X-ray studies. Results: We identified 16 HRCT and 36 X-ray studies. We rated six HRCT and 16 X-ray studies as higher quality based on a risk-of-bias analysis. Half of the higher quality studies reported small but statistically significant mean lung function decrements associated with plaques. None of the differences were clinically significant. Many studies had limitations, such as inappropriate controls and/or insufficient adjustment for confounders. There was little consistency in the direction of effect for the most commonly reported measurements. X-ray results were more variable than HRCT results. Pleural plaques were not associated with changes in lung function over time in longitudinal studies. Conclusion: The weight of evidence indicates that pleural plaques do not impact lung function. Observed associations are most likely due to unidentified abnormalities or other factors. © 2015 Informa Healthcare USA, Inc.


Clark K.A.,University of South Carolina | Flynn J.J.,III | Goodman J.E.,Gradient Corporation | Goodman J.E.,Harvard University | And 3 more authors.
Chest | Year: 2014

METHODS: The results of HRCT scanning and complete PFTs performed between January 2000 and August 2012 were obtained from the medical records of 166 Libby vermiculite miners. Multivariate regression analyses with Tukey multivariate adjustment were used to assess statistical associations between the presence of PPs and lung function. Adjustments were made for age, BMI, smoking history, duration of employment, and years since last occupational asbestos exposure.RESULTS: Nearly 90% of miners (n = 149) had evidence of PPs on HRCT scan. No significant differences in spirometry results, lung volumes, or diffusing capacity of the lung for carbon monoxide were found between miners with PPs alone and miners with normal HRCT scans. Miners with both interstitial fibrosis and the presence of PPs had a significantly decreased total lung capacity in comparison with miners with normal HRCT scans ( P = .02). Age, cumulative smoking history, and BMI were significant covariates that contributed to abnormal lung function.CONCLUSIONS: Asbestos-related PPs alone have no significant effect on lung function in Libby vermiculite miners. © 2014 AMERICAN COLLEGE OF CHEST PHYSICIANS.BACKGROUND: Multiple studies have investigated the relationship between asbestos-related pleural plaques (PPs) and lung function, with disparate and inconsistent results. Most use chest radiographs to identify PPs and simple spirometry to measure lung function. High resolution CT (HRCT) scanning improves the accuracy of PP identification. Complete pulmonary function tests (PFTs), including spirometry, lung volumes, and diffusing capacity of the lung for carbon monoxide, provide a more definitive assessment of lung function. The goal of this study was to determine, using HRCT scanning and complete PFTs, the effect of PPs on lung function in Libby vermiculite miners.


Moffett J.W.,University of Southern California | Tuit C.B.,Princeton University | Tuit C.B.,Gradient Corporation | Ward B.B.,Princeton University
Limnology and Oceanography | Year: 2012

Copper (Cu) is required by the enzyme nitrous oxide reductase (N2OR), which catalyzes the last step of the complete denitrification pathway in denitrifying bacteria. Some denitrifiers also require copper for nitrite reductase (NiRK), whereas others use the iron nitrite reductase (NiRS). We report the inhibition of the activity of these enzymes in three strains of denitrifiers (two containing NiRK, the other NiRS), by forming nonbioavailable complexes with 1,4,8,11-tetraazacyclotetradecane1,4,8,11-tetraacetic acid hydrochoride hydrate (TETA), a strong Cu(II) chelator, and tetrathiomolybdate (TTMo), a strong Cu(I) chelator. Both ligands complex Cu with stability constants comparable to naturally occurring ligands and much more strongly than other widely used chelators, such as ethylenediaminetetraacetic acid. Addition of TETA to growth media lowered free Cu2+ concentrations below 10-16 mol L-1 and induced Cu limitation in all organisms. While Cu is strongly complexed in seawater, 10-16 mol L-1 free Cu2+ is lower than most reported values, suggesting that the organisms have evolved highaffinity Cu transport systems. TTMo had different effects, and inhibited NiRK more effectively than N2OR. It is likely that TTMo inhibits NiRK through direct, noncompetitive inhibition, as reported for other reduced sulfur compounds, rather than by inducing Cu limitation. The activity of NiRK may be sensitive to trace levels of reduced sulfur, which could account for its scarcity in marine systems. While Cu limitation of denitrification is probably uncommon in aquatic systems, the presence of reduced sulfur compounds may induce Cu limitation or enzyme inhibition leading to the accumulation of nitrite and nitrous oxide. © 2012, by the Association for the Sciences of Limnology and Oceanography, Inc.


Radloff K.A.,Columbia University | Radloff K.A.,Lamont Doherty Earth Observatory | Radloff K.A.,Gradient Corporation | Zheng Y.,Lamont Doherty Earth Observatory | And 14 more authors.
Nature Geoscience | Year: 2011

The consumption of shallow groundwater with elevated concentrations of arsenic is causing widespread disease in many parts of South and Southeast Asia. In the Bengal Basin, a growing reliance on groundwater sourced below 150-m depth - where arsenic concentrations tend to be lower - has reduced exposure. Groundwater flow simulations have suggested that these deep waters are at risk of contamination due to replenishment with high-arsenic groundwater from above, even when deep water pumping is restricted to domestic use. However, these simulations have neglected the influence of sediment adsorption on arsenic migration. Here, we inject arsenic-bearing groundwater into a deep aquifer zone in Bangladesh, and monitor the reduction in arsenic levels over time following stepwise withdrawal of the water. Arsenic concentrations in the injected water declined by 70% after 24 h in the deep aquifer zone, owing to adsorption on sediments; concentrations of a co-injected inert tracer remain unchanged. We incorporate the experimentally determined adsorption properties of sands in the deep aquifer zone into a groundwater flow and transport model covering the Bengal Basin. Simulations using present and future scenarios of water-use suggest that arsenic adsorption significantly retards transport, thereby extending the area over which deep groundwater can be used with low risk of arsenic contamination. Risks are considerably lower when deep water is pumped for domestic use alone. Some areas remain vulnerable to arsenic intrusion, however, and we suggest that these be prioritized for monitoring. © 2011 Macmillan Publishers Limited. All rights reserved.


Lewandowski T.A.,Brooklyn College | Lewandowski T.A.,Gradient LLC
NATO Science for Peace and Security Series C: Environmental Security | Year: 2011

Over the last decade autism and autistic spectrum disorders (ASD) have become an increasing focus of scientific research and public interest. The idea that mercury exposure may play a causative role in autism was first suggested in connection with postnatal exposures to ethylmercury via vaccination. This hypothesis has not been supported by the results of several large epidemiology studies and scientific reviews but nonetheless the notion that mercury in vaccines causes autism has remained fixed in the public mind. Several ecological studies have also suggested that inorganic mercury exposures from environmental (i.e., non-vaccine) sources are correlated with autism prevalence. To better understand some of the limitations of these ecological analyses, and to explore the robustness of the mercury-autism hypothesis, we used data collected for the U.S. State of Texas to examine whether other surrogate exposure measures (e.g., emissions of other chemicals, downwind status from a power plant, local fish consumption advisories) and different analytical approaches led to similar findings. Using multilevel Poisson regression analysis we found that air mercury emissions reports were significantly associated with same year autism prevalence in Texas school districts using data obtained for 2001 and 2002 but that associations were not significant using data from 2003 to 2005. Evaluations using other surrogate exposure variables (i.e., downwind location from coal-fired power plants or existence of mercury related fish consumption advisories) also did not yield statistically significant associations. We did observe that the treatment of censored data had an important effect on the analysis; results which were statistically significant when censored data were handed as zeros became non statistically significant when they were treated as the mid-point of the censored range. This indicates that what is required to clearly answer questions about environmental mercury and autism is a well controlled case-control or cohort study with extensive pre- and post-natal mercury exposure assessment. Government agencies, advocacy groups and mercury emitting industries should all consider supporting such studies so that this contentious health concern can be definitively addressed. © Springer Science+Business Media B.V. 2011.

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