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Full-Text Articles in Physical Sciences and Mathematics

Microbial Diversity In Urban Environments: Concern For Antibiotic Resistance, Ality Aghedo, Mangala Tawde, Nazrul I. Khandaker Nov 2018

Microbial Diversity In Urban Environments: Concern For Antibiotic Resistance, Ality Aghedo, Mangala Tawde, Nazrul I. Khandaker

Publications and Research

We are almost oblivious to the presence of microorganisms in our daily lives, but they exist and come into contact with us all the time. While some bacteria are harmless, and even beneficial, other bacteria can cause infections. A common treatment to bacterial infections is antibiotics and the success of an antibiotic depends on the resistance of the bacteria to the antibiotic. We conducted experiments to identify the types of bacteria that can be found on surfaces or within soil environments that come into contact with a vast number of people on a daily basis and how this can affect …


An Overview Of Smartwater Management System: Strategic Potential In Bangladesh, Muhammad Qumrul Hassan, Mir F. Karim, Nazrul I. Khandaker, Jowaher Raza Nov 2018

An Overview Of Smartwater Management System: Strategic Potential In Bangladesh, Muhammad Qumrul Hassan, Mir F. Karim, Nazrul I. Khandaker, Jowaher Raza

Publications and Research

Water loss management is becoming an increasingly important as supplies are stressed by population growth or water scarcity. A SmartWater system ensures optimum consumption and prediction of future water use. Bangladesh is one of the most vulnerable countries due to global climate change considering its rapid urbanization, inequitable land use, low income and greater reliance on climate sensitive sectors, particularly agriculture. Agricultural lands used for cropping and livestock rearing are more susceptible to degradation than non-agricultural lands. Most farmers irrigate through flooding, losing up to 75% of water to evaporation and creating a substantial drawdown of much needed water for …


The Status Of Engineering Geology: Constraints On Infrastructure Development In Bangladesh, Mir Fazlul Karim, Muhammad Qumrul Hassan, Nazrul I. Khandaker, Masud Ahmed, Belal Ahmed Sayeed Nov 2018

The Status Of Engineering Geology: Constraints On Infrastructure Development In Bangladesh, Mir Fazlul Karim, Muhammad Qumrul Hassan, Nazrul I. Khandaker, Masud Ahmed, Belal Ahmed Sayeed

Publications and Research

In recent years, megacity Dhaka is known to have one of the fastest urban population growths in Bangladesh. The population in Dhaka and other megacities has increased from 7 to 50 million during the last four decades. The rapid rate of urban population growth, along with the extreme paucity of real-estate for new infrastructure development or upgrading existing facilities, is already exacerbating the situation for the city planners and exerting tremendous pressure to come-up with viable solutions. Although practice of engineering geology, geotechnical exploration, and testing exists in Bangladesh; the system has still yet to adopt controlled quality standards with …


Water Flow Net Characterization By Using A Tank Model: Preliminary Outcome, Jasmin Budhan, Nazrul I. Khandaker, Stanley Schleifer Nov 2018

Water Flow Net Characterization By Using A Tank Model: Preliminary Outcome, Jasmin Budhan, Nazrul I. Khandaker, Stanley Schleifer

Publications and Research

A model study was conducted to observe and characterize the flow of water through sandy soil. One of the most relevant tools used for characterizing groundwater flow is the flow net. Assuming that water is incompressible and there is zero volume change in the soil mass, it is known that the total rate of inflow is to equal the total rate of outflow. Thus, following the principle of flow continuity, we use the Laplace equation of continuity, to observe the concept of the flow net. Computing the flow through a miniature channel, we observed the total head difference from the …


Nasa Maa (Murep Aerospace Academy) Stem Project At York College: Ensuring Future Stem Pipeline, Nazrul I. Khandaker, Shuayb Siddique, Matthew Khargie, Brandon Dhanraj, Zachary A. Sanichar, Mildred M. Selby, Chabenauth Ramnauth, Theresa Deepan, Yougeeta Singh, Krishna Mahabir, Sashi Singh, Omadevi Singh Nov 2018

Nasa Maa (Murep Aerospace Academy) Stem Project At York College: Ensuring Future Stem Pipeline, Nazrul I. Khandaker, Shuayb Siddique, Matthew Khargie, Brandon Dhanraj, Zachary A. Sanichar, Mildred M. Selby, Chabenauth Ramnauth, Theresa Deepan, Yougeeta Singh, Krishna Mahabir, Sashi Singh, Omadevi Singh

Publications and Research

Our ongoing K1-12 NASA-supported STEM activities has served over 5000 children since 2015, largely from groups that are undeserved and underrepresented in the sciences. These STEM activities have been successfully delivered for several years and include earth science, meteorite geology, rocketry, aerodynamics, star gazing, EV3 Mindstorm robotics, basic coding exercises, wind tunnel, 3D-printing, etc., conducted largely through our present MAA (MUREP Aerospace Academy) Project. Corporate funding from the Con Edison and National Grid ensures additional STEM dissemination to the students during the summer operation. Significant positive component of the MAA program is the availability and willingness of the former student …


Recruiting And Retaining K9–16 Students Through Field- And Laboratory - Based Geoscience Experiences, Nazrul I. Khandaker, Stanley Schleifer, Arif M. Sikder, Krishna Mahabir, Ality Aghedo, Charren Cabaroy, Mildred M. Selby, Gugu Ginindza, Leonardo Sanchez Nov 2018

Recruiting And Retaining K9–16 Students Through Field- And Laboratory - Based Geoscience Experiences, Nazrul I. Khandaker, Stanley Schleifer, Arif M. Sikder, Krishna Mahabir, Ality Aghedo, Charren Cabaroy, Mildred M. Selby, Gugu Ginindza, Leonardo Sanchez

Publications and Research

Since 2004, we have been directly involved with the GSA to provide access and opportunities for K9-16 students, particularly those interested in the broader aspects of geoscience-related topics, to present their field-and- laboratory based research outcomes at professional conferences and to learn from each other. So far, well-over 400 students from the U. S. and abroad have taken advantage of this opportunity and participated our topical sessions. It is quite gratifying to report that many of these students, as a result of their attendance at the GSA conference, felt a continuing need for exposure to high-level professional venues with effective …


The Challenges Of Geotechnical Exploration In Bangladesh For Sustainable Urban Development And Risk Reductions In Engineering Geology, Mir Fazul Karim, Nazrul I. Khandaker, Muhammad Qumrul Hasson, A.T.M. Shakhawat Hossain Nov 2018

The Challenges Of Geotechnical Exploration In Bangladesh For Sustainable Urban Development And Risk Reductions In Engineering Geology, Mir Fazul Karim, Nazrul I. Khandaker, Muhammad Qumrul Hasson, A.T.M. Shakhawat Hossain

Publications and Research

Bangladesh is a unique example of rapid urbanization where the urban population increased from 5 to 58 million in last four decades. Due to complex geology and active tectonic setting, the urban ground is impacted by fluvio-deltaic processes and regional seismicity. The densely populated cities of the country are facing risks from many natural hazards like floods, tidal surge, riverbank and coastal erosion, scour, landslides, soil collapse and foundation failures. Geologists anticipate severe seismic threats from yet-undefined tectonic structures and seek to determine their consequential geo-structural responses and conformance to the national building code. With rapid growth, demands on infrastructure …


Season-Ahead Forecasting Of Water Storage And Irrigation Requirements – An Application To The Southwest Monsoon In India, Arun Ravindranath, Naresh Devineni, Upmanu Lall, Paulina Concha Larrauri Oct 2018

Season-Ahead Forecasting Of Water Storage And Irrigation Requirements – An Application To The Southwest Monsoon In India, Arun Ravindranath, Naresh Devineni, Upmanu Lall, Paulina Concha Larrauri

Publications and Research

Water risk management is a ubiquitous challenge faced by stakeholders in the water or agricultural sector. We present a methodological framework for forecasting water storage requirements and present an application of this methodology to risk assessment in India. The application focused on forecasting crop water stress for potatoes grown during the monsoon season in the Satara district of Maharashtra. Pre-season large-scale climate predictors used to forecast water stress were selected based on an exhaustive search method that evaluates for highest ranked probability skill score and lowest root-mean-squared error in a leave-one-out cross-validation mode. Adaptive forecasts were made in the years …


Observed Differences Between Near-Surface Air And Skin Temperatures Using Satellite And Ground-Based Data, Satya Prakash, Farjana Shati, Hamidreza Norouzi, Reginald Blake Sep 2018

Observed Differences Between Near-Surface Air And Skin Temperatures Using Satellite And Ground-Based Data, Satya Prakash, Farjana Shati, Hamidreza Norouzi, Reginald Blake

Publications and Research

Accurate estimates of long-term land surface temperature (Ts) and near-surface air temperature (Ta) at finer spatio-temporal resolutions are crucial for surface energy budget studies, for environmental applications, for land surface model data assimilation, and for climate change assessment and its associated impacts. The Atmospheric Infrared Sounder (AIRS) and Moderate Resolution Imaging Spectroradiometer (MODIS) sensors onboard the Aqua satellite provide a unique opportunity to estimate both temperatures twice daily at the global scale. In this study, differences between Ta and Ts were assessed locally over regions of North America from 2009 to 2013 …


Recent Trends In The Frequency And Duration Of Global Floods, Nasser Najibi, Naresh Devineni Jun 2018

Recent Trends In The Frequency And Duration Of Global Floods, Nasser Najibi, Naresh Devineni

Publications and Research

Frequency and duration of floods are analyzed using the global flood database of the Dartmouth Flood Observatory (DFO) to explore evidence of trends during 1985–2015 at global and latitudinal scales. Three classes of flood duration (i.e., short: 1–7, moderate: 8–20, and long: 21 days and above) are also considered for this analysis. The nonparametric Mann–Kendall trend analysis is used to evaluate three hypotheses addressing potential monotonic trends in the frequency of flood, moments of duration, and frequency of specific flood duration types. We also evaluated if trends could be related to large-scale atmospheric teleconnections using a generalized linear model framework. …


Hip Extensor Mechanics And The Evolution Of Walking And Climbing Capabilities In Humans, Apes, And Fossil Hominins, Elaine E. Kozma, Nicole M. Webb, William Harcourt-Smith, David A. Raichlen, Kristiaan D’Août, Mary H. Brown, Emma M. Finestone, Stephen R. Ross, Peter Aerts, Herman Pontzer Apr 2018

Hip Extensor Mechanics And The Evolution Of Walking And Climbing Capabilities In Humans, Apes, And Fossil Hominins, Elaine E. Kozma, Nicole M. Webb, William Harcourt-Smith, David A. Raichlen, Kristiaan D’Août, Mary H. Brown, Emma M. Finestone, Stephen R. Ross, Peter Aerts, Herman Pontzer

Publications and Research

The evolutionary emergence of humans’ remarkably economical walking gait remains a focus of research and debate, but experi- mentally validated approaches linking locomotor capability to postcranial anatomy are limited. In this study, we integrated 3D morphometrics of hominoid pelvic shape with experimental mea- surements of hip kinematics and kinetics during walking and climbing, hamstring activity, and passive range of hip extension in humans, apes, and other primates to assess arboreal–terrestrial trade-offs in ischium morphology among living taxa. We show that hamstring-powered hip extension during habitual walking and climbing in living apes and humans is strongly predicted, and likely constrained, by …


Estimation Of Consistent Global Microwave Land Surface Emissivity From Amsr-E And Amsr2 Observations, Satya Prakash, Hamidreza Norouzi, Marzi Azarderakhsh, Reginald Blake, Catherine Prigent, Reza Khanbilvardi Apr 2018

Estimation Of Consistent Global Microwave Land Surface Emissivity From Amsr-E And Amsr2 Observations, Satya Prakash, Hamidreza Norouzi, Marzi Azarderakhsh, Reginald Blake, Catherine Prigent, Reza Khanbilvardi

Publications and Research

Accurate estimation of passive microwave land surface emissivity (LSE) is crucial for numerical weather prediction model data assimilation, for microwave retrievals of land precipitation and atmospheric profiles, and for better understanding of land surface and sub-surface characteristics. In this study, global instantaneous LSE is estimated for the 9-year period from the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) and for the 5-year period from the Advanced Microwave Scanning Radiometer - 2 (AMSR2) sensors. Estimates of LSE from both sensors were obtained by using an updated algorithm that minimizes the discrepancy between the differences in penetration depths from microwave …


Bathymetry Data For Lakes Azuei And Enriquillo, Michael Piasecki, Mahrokh Moknatian Feb 2018

Bathymetry Data For Lakes Azuei And Enriquillo, Michael Piasecki, Mahrokh Moknatian

Publications and Research

This data set supports and forms the basis for the development of Digital Bathymetry Models (DBM) for Lakes Azuei (Haiti) and Enriquillo (Dominican Republic). Bathymetric Data is typically acquired using Sonar devices that measure the depth at specific points along a boat track and for which the longitude and latitude is recorded. From the resulting point cloud one develop a seamless representation of the floor of the lake on either a raster set (which is what we have done) or try to use a contour (vector representation) model in which the depth contours appear as polygons or -lines. The raw …


Evolution Of The Modern Baboon (Papio Hamadryas): A Reassessment Of The African Plio-Pleistocene Record, Christopher C. Gilbert, Stephen R. Frost, Kelsey D. Pugh, Monya Anderson, Eric Delson Jan 2018

Evolution Of The Modern Baboon (Papio Hamadryas): A Reassessment Of The African Plio-Pleistocene Record, Christopher C. Gilbert, Stephen R. Frost, Kelsey D. Pugh, Monya Anderson, Eric Delson

Publications and Research

Baboons ( Papio hamadryas) are among the most successful extant primates, with a minimum of six distinctive forms throughout Sub-Saharan Africa. However, their presence in the fossil record is unclear. Three early fossil taxa are generally recognized, all from South Africa: Papio izodi , Papio robinsoni and Papio angusticeps. Because of their derived appearance, P. angusticeps and P. robinsoni have sometimes been considered subspecies of P. hamadryas and have been used as biochronological markers for the Plio- Pleistocene hominin sites where they are found.

We reexamined fossil Papio forms from across Africa with an emphasis on their distinguishing features and …


Supercycle In Great Earthquake Recurrence Along The Japan Trench Over The Last 4000 Years, Kazuko Usami, Ken Ikehara, Toshiya Kanamatsu, Cecilia M. Mchugh Jan 2018

Supercycle In Great Earthquake Recurrence Along The Japan Trench Over The Last 4000 Years, Kazuko Usami, Ken Ikehara, Toshiya Kanamatsu, Cecilia M. Mchugh

Publications and Research

On the landward slope of the Japan Trench, the mid-slope terrace (MST) is located at a depth of 4000–6000 m. Two piston cores from the MST were analyzed to assess the applicability of the MST for turbidite paleoseismology and to find out reliable recurrence record of the great earthquakes along the Japan Trench. The cores have preserved records of ~ 12 seismo-turbidites (event deposits) during the last 4000 years. In the upper parts of the two cores, only the following earthquakes (magnitude M ~ 8 and larger) were clearly recorded: the 2011 Tohoku, the 1896 Sanriku, the 1454 Kyotoku, and …