Life Sciences Commons^™

A Holistic Approach To Performance Prediction In Collegiate Athletics: Player, Team, And Conference Perspectives, Christopher Taber, S. Sharma, Mehul S. Raval, Samah Senbel, Allison Keefe, Jui Shah, Emma Patterson, Julie K. Nolan, N.S. Artan, Tolga Kaya

Exercise Science Faculty Publications

Predictive sports data analytics can be revolutionary for sports performance. Existing literature discusses players' or teams' performance, independently or in tandem. Using Machine Learning (ML), this paper aims to holistically evaluate player-, team-, and conference (season)-level performances in Division-1 Women's basketball. The players were monitored and tested through a full competitive year. The performance was quantified at the player level using the reactive strength index modified (RSImod), at the team level by the game score (GS) metric, and finally at the conference level through Player Efficiency Rating (PER). The data includes parameters from training, subjective stress, sleep, and recovery (WHOOP …

Training The Concept Of Innovate In Dolphins (Tursiops Truncatus) Is Both Creative And Cognitively Stimulating, Deirdre Yeater, Kathleen M. Dudzinski, Dawn Melzer, Andrew R. Magee, Michaela Robinett, Gonzalo Guerra, Kimberly Salazar, Terri Bolton, Heather Manitzas Hill

Psychology Faculty Publications

Creative or novel behaviors in bottlenose dolphins (Tursiops truncatus) can be indicators of flexible thinking and problem solving. Over 50 years ago, two rough-tooth dolphins demonstrated creative novel behaviors acquired through reinforcement training in human care. Since this novel training, a variety of species have been trained to respond to this conceptual cue. The current study assessed the creativity of 12 bottlenose dolphins (5 females, 7 males) housed at the Roatan Institute for Marine Sciences (RIMS) in Roatan, Honduras. Individual differences were found across four constructs measured for creativity: fluency, flexibility, elaboration, and originality. Variability in performance occurred across test …

Mechanics Of The Foot And Ankle Joints During Running Using A Multi-Segment Foot Model Compared With A Single-Segment Model, Justin C. Wager, John H. Challis

Exercise Science Faculty Publications

The primary purpose of this study was to compare the ankle joint mechanics, during the stance phase of running, computed with a multi-segment foot model (MULTI; three segments) with a traditional single segment foot model (SINGLE). Traditional ankle joint models define all bones between the ankle and metatarsophalangeal joints as a single rigid segment (SINGLE). However, this contrasts with the more complex structure and mobility of the human foot, recent studies of walking using more multiple-segment models of the human foot have highlighted the errors arising in ankle kinematics and kinetics by using an oversimplified model of the foot. This …

Acute Ingestion Of Dark Chocolate Fails To Affect Running Economy In Recreationally Trained Female Runners, Bianca De Lucia, Beau K. Greer, Christopher B. Taber

PTHMS Graduate Publications

Ingestion of dark chocolate (DC), a dietary source high in flavanols, may increase nitric oxide bioavailability. Elevating blood nitric oxide concentrations may augment metabolic efficiency by reducing the amount of oxygen or energy needed to perform a given task. Utilizing a crossover design, the purpose of this study was to investigate the effect of acute ingestion of DC on running economy (RE). Nineteen recreationally trained females (age: 20±1 years) volunteered for this investigation, with 16 completing all procedures (n = 16). Two-hours before RE assessment, participants consumed either 42.5 g of DC or an isocaloric amount of white chocolate (WC) …

Mitochondrial Metabolism In Blood More Reliably Predicts Whole-Animal Energy Needs Compared To Other Tissues, Stefania Casagrande, Maciej Dzialo, Lisa Trost, Kasja Malkoc, Edyta T. Sadowska, Michaela Hau, Barbara J. Pierce, Scott R. Mcwilliams, Ulf Bauchinger

Biology Faculty Publications

Understanding energy metabolism in free-ranging animals is crucial for ecological studies. In birds, red blood cells (RBCs) offer a minimally invasive method to estimate metabolic rate (MR). In this study with European starlings Sturnus vulgaris, we examined how RBC oxygen consumption relates to oxygen use in key tissues (brain, liver, heart, and pectoral muscle) and versus the whole-organism measured at basal levels. The pectoral muscle accounted for 34-42% of organismal MR, while the heart and liver, despite their high mass-specific metabolic rate, each contributed 2.5-3.0% to organismal MR. Despite its low contribution to organismal MR (0.03-0.04%), RBC MR best predicted …

A Framework For Biomechanical Analysis Of Jump Landings For Injury Risk Assessment, Srishti Sharma, Srikrishnan Divakaran, Kaya Tolga, Christopher B. Taber, Mehul S. Raval

School of Computer Science & Engineering Faculty Publications

Competitive sports require rapid and intense movements, such as jump landings, making athletes susceptible to injuries due to altered neuromuscular control and joint mechanics. Biomechanical features during landings are associated with injury risk, emphasizing proper movement and postural stability. Computer vision techniques offer a time-efficient, noninvasive, and unbiased method to assess jump-landings and identify injury risks. This study proposes a video analysis framework to evaluate jump landing biomechanics in athletes todetermineirregularmovementsandincorrectpostures.It providesadviceandrecommendationstocoachesforinjury predictionandtrainingimprovements.Theproposedframework istestedusingcountermovementjumpvideosof17NCAA DivisionIfemalebasketballathletes.Theresultsindicateda lowMeanAbsoluteError(0.97),highcorrelation(0.89),high averageaccuracy(98.31%)andF1score(0.98),signifyingthe framework’sreliabilityinidentifyinginjuryrisk.

Low-Cost Pm2.5 Sensors Can Help Identify Driving Factors Of Poor Air Quality And Benefit Communities, Tim Keyes, Rea Domingo, Samantha Dynowski, Royal Graves, Martha Klein, Melissa Leonard, John Pilgrim, Alison Sanchirico, Kate Trinkaus

WCBT Faculty Publications

Air quality is critical for public health. Residents rely chiefly on government agencies such as the Environmental Protection Agency (EPA) in the United States to establish standards for the measurement of harmful contaminants including ozone, sulfur dioxide, carbon monoxide, volatile organic chemicals (VOCs), and fine particulate matter at or below 2.5 μm. According to the California Air Resources Board [1], “short-term PM2.5 exposure (up to 24-h duration) has been associated with premature mortality, increased hospital admissions for heart or lung causes, acute and chronic bronchitis, asthma attacks, emergency room visits, respiratory symptoms, and restricted activity days”. While public agency resources …

Concerted Phenotypic Flexibility Of Avian Erythrocyte Size And Number In Response To Dietary Anthocyanin Supplementation, Maciej Dzialo, Amadeusz Bryla, Kristen J. Demoranville, Katherine M. Carbeck, Olivia Fatica, Lisa Trost, Barbara J. Pierce, Edyta T. Sadowska, Scott R. Mcwilliams, Ulf Bauchinger

Biology Faculty Publications

Background: Endurance flight impose substantial oxidative costs on the avian oxygen delivery system. In particular, the accumulation of irreversible damage in red blood cells can reduce the capacity of blood to transport oxygen and limit aerobic performance. Many songbirds consume large amounts of anthocyanin-rich fruit, which is hypothesized to reduce oxidative costs, enhance post-flight regeneration, and enable greater aerobic capacity. While their antioxidant benefits appear most straightforward, the effects of anthocyanins on blood composition remain so far unknown. We fed thirty hand-raised European starlings (Sturnus vulgaris) two semisynthetic diets (with or without anthocyanin supplement) and manipulated the extent of flight …

Conceptualizing The Construct Of Ocean Identity, Miriah R. Kelly, Jo-Marie Kasinak, Emma Mckinley, Caitlin Mclaughlin, Jamie M.P. Vaudrey, Jennifer Mattei

Biology Faculty Publications

The construct of ocean identity provides a valuable lens that can unpack the multiple dimensions of human connections with ocean spaces, and crucially places importance on the integration of cognitive, affective, and behavioral components. The construct of ocean identity is applicable in academic and professional contexts, and is largely unexplored from both qualitative and quantitative research perspectives. This comment article presents a revised definition of ocean identity and posits a useful conceptual framework based on a robust analysis of literature to unveil the multiple dimensions that may explain an individuals’ ocean identity. Here we identify a series of attributes that …

Does Physical Activity Moderate The Association Between Shorter Leukocyte Telomere Length And Incident Coronary Heart Disease? Data From 54,180 Uk Biobank Participants, Meiruo Xiang, Luke C. Pilling, David Melzer, Ben Kirk, Gustavo Duque, Rui Liu, George A. Kuchel, Andrew R. Wood, Brad Metcalf, Breno S. Diniz, Melvyn Hillsdon, Chia-Ling Kuo

Health Science Faculty Publications

Telomere shortening is a biological aging hallmark. The effect of short telomere length may be targeted by increased physical activity to reduce the risk of multiple aging-related diseases, including coronary heart disease (CHD). The objective was to assess the moderation effect of accelerometer-based physical activity (aPA) on the association between shorter leukocyte telomere length (LTL) relatively in the population sample and incident CHD. Data were from the UK Biobank participants with well-calibrated accelerometer data for at least 6.5 days (n = 54,180). Relative mean LTL at baseline (5–6 years prior to aPA assessment) was measured in T/S ratio, using a …

Validity And Reliability Of A Computer Vision System To Determine Bar Displacement And Velocity, Christopher Taber, Emma Patterson, Jui Shah, Padraig Francis, Justin C. Wager

Exercise Science Faculty Publications

This study examined the validity and reliability of a video-based smartphone application (VBA) to measure displacement and velocity in the barbell bench press, back squat, and deadlift. Nine resistance-trained subjects (three females; six males; age: 24.2±4.2 years; height 175.8±8.1 cm; body mass 87.2±18.2kg) completed two test-retest sessions for the barbell bench press, back squat, and deadlift one week apart. Eight repetitions were completed for the bench press, back squat, and deadlift with a load of 40kg and completed at fast and slow velocities. Bar displacement and average velocity were measured simultaneously using 3-D motion capture (MC) and a VBA. The …

Evidence For A Single, Ancient Origin Of A Genus-Wide Alternative Life History Strategy, Kalle Tunström, Alyssa Woronik, Joseph J. Hanly, Pasi Rastas, Anton Chichvarkhin, Andrew D. Warren, Akito Kawahara, Sean D. Schoville, Vincent Ficarrotta, Adam H. Porter, Ward B. Watt, Arnaud Martin, Christopher W. Wheat

Biology Faculty Publications

Understanding the evolutionary origins and factors maintaining alternative life history strategies (ALHS) within species is a major goal of evolutionary research. While alternative alleles causing discrete ALHS are expected to purge or fix over time, one-third of the ~90 species of Colias butterflies are polymorphic for a female-limited ALHS called Alba. Whether Alba arose once, evolved in parallel, or has been exchanged among taxa is currently unknown. Using comparative genome-wide association study (GWAS) and population genomic analyses, we placed the genetic basis of Alba in time-calibrated phylogenomic framework, revealing that Alba evolved once near the base of the genus and …

The Effects Of Accentuated Eccentric Loading On Barbell And Trap Bar Countermovement Jumps, Christopher B. Taber, Calin Butler, Victoria Dabek, Benjamin Kochan, Kyle Mccormick, Emily Petro, Timothy J. Suchomel, Justin Merrigan

Exercise Science Faculty Publications

This study examined effects of accentuated eccentric loading (AEL) on barbell and trap bar loaded countermovement jumps (LCMJ). Twenty-one subjects (16 male, 5 female; Age: 23.5 ± 1.8 years; Body mass: 81.4 ± 10.6 kg; Height: 176.9 ± 7.2 cm; Training age: 7.1 ± 2.6 years) participated in this study. Upon establishing one repetition maximum and baseline jumping conditions, three experimental loading sessions were completed in random order. Barbell and trap bar LCMJ were performed with a spectrum of fixed loads from 20-50 kg during control conditions and with additional AEL loads of 10, 20, or 30 kg for experimental …

Inter-Session Repeatability Of Marker-Less Motion Capture Of Treadmill Running Gait, Matthew F. Moran, Isabella C. Rogler, Justin C. Wager

Exercise Science Faculty Publications

Twenty-one experienced runners completed three treadmill running sessions on different days. Each session consisted of three consecutive 2 min trials at self-selected speeds (RPE = 3, 5, and 7). An eight-camera marker-less motion capture system and instrumented pressure treadmill (TM) collected data over the final ~25 s at each speed. Lower extremity joint angles (ankle, knee, and hip) and segmental angles (pelvis and trunk) were computed for each trial with foot contact and toe off being kinematically determined. Spatiotemporal metrics (ground contact time, step length, and cadence) were measured via TM and compared to their kinematically derived counterparts. All spatiotemporal …

Our Natural World, Jennifer Mattei

Biology Faculty Publications

It’s nothing earth-shattering to say our natural world gives us everything we need to survive, from the oxygen we breathe and the clean water we drink to that apple you are enjoying with your lunch today. We all know this. However, we sometimes fail to appreciate and act on the converse—if we fail to maintain a well-functioning and resilient natural world our future is literally at risk.

What’s more, our reliance on nature goes deeper than the base physical essentials of air, water and food that are required for life. Our bodies—physically, mentally and emotionally—are healthier for their interaction with …

Molecular Basis For Integrin Adhesion Receptor Binding To P21-Activated Kinase 4 (Pak4), Byung Hak Ha, Sezin Yigit, Nailini Natarajan, Elizabeth M. Luoma, David A. Calderwood, Titus J. Boggon

SHU Faculty Publications

Integrin adhesion receptors provide links between extracellular ligands and cytoplasmic signaling. Multiple kinases have been found to directly engage with integrin β tails, but the molecular basis for these interactions remain unknown. Here, we assess the interaction between the kinase domain of p21-activated kinase 4 (PAK4) and the cytoplasmic tail of integrin β5. We determine three crystal structures of PAK4-β5 integrin complexes and identify the PAK-binding site. This is a region in the membrane-proximal half of the β5 tail and confirmed by site-directed mutagenesis. The β5 tail engages the kinase substrate-binding groove and positions the non-phosphorylatable integrin residue Glu767 at …

Cascon 2022, College Of Arts & Sciences

SHU Faculty Publications

CASCon showcases the work of Sacred Heart University faculty from multiple disciplines. The conference emphasizes the interdisciplinary nature of faculty scholarship and reaffirms the College’s commitment to undergraduate research.

6th Annual College of Arts & Sciences Conference (CASCon) on Wednesday, September 28, 2022.

Application Of Accentuated Eccentric Loading To Elicit Acute And Chronic Velocity And Power Improvements: A Narrative Review, Justin Merrigan, Jonathon Borth, Christopher B. Taber, Timothy J. Suchomel, Margaret Jones

Exercise Science Faculty Publications

No abstract provided.

The Effects Of Body Tempering On Force Production, Flexibility And Muscle Soreness In Collegiate Football Athletes, Christopher B. Taber, Roy Colter, Jair J. Davis, Patrick A. Seweje, Dustin P. Wilson, Jonathan Z. Foster, Justin J. Merrigan

Exercise Science Faculty Publications

There has been limited research to explore the use of body tempering and when the use of this modality would be most appropriate. This study aimed to determine if a body tempering intervention would be appropriate pre-exercise by examining its effects on perceived soreness, range of motion (ROM), and force production compared to an intervention of traditional stretching. The subjects for this study were ten Division 1 (D1) football linemen from Sacred Heart University (Age: 19.9 ± 1.5 years, body mass: 130.9 ± 12.0 kg, height: 188.4 ± 5.1 cm, training age: 8.0 ± 3.5 years). Subjects participated in three …

Twelve Week Calcium Collagen Chelate Or Calcium Plus Vitamin D Supplementation Does Not Affect Bone Metabolism In Trained Cyclists, Beau K. Greer, Christopher Mojock, Bahram Arjmandi, Jeong-Su Kim, Michael Ormsbee, Lynn Panton

Exercise Science Faculty Publications

The purpose of the present study was to determine whether 12 weeks of calcium collagen chelate (CCC) supplementation during habitual training would affect body composition, bone mineral density (BMD), and biomarkers of bone metabolism in competitive cyclists. Twenty trained (maximal aerobic capacity > 50 ml/kg/min, mean training volume: 28 h/wk) male cyclists performed maximal exercise testing and 40-km time trials (TT) on an electronically braked cycle ergometer. BMD of the whole body, lumbar spine (L1-L4), and both hips were measured via dual-energy X-ray absorptiometry (DXA). The cyclists were assigned to one of two groups: 1) 6 g/d of CCC with 600 …

Comparing Mean & Peak Barbell Velocity During Traditional And Accentuated Eccentric Loaded Back Squats, Zach S. Schroeder, Lauren K. Marshall, Lea C. Katanick, Brookelyn A. Campbell, Conor J. Cantwell, Christopher B. Taber, Timothy J. Suchomel

Exercise Science Faculty Publications

MV: There were statistically significant main effects present for both condition (p = 0.002; g = 0.10-0.23) and load (p < 0.001; g = 0.95-3.93). However, the condition x time interaction effect was not statistically significant (p = 0.259). • PV: There were statistically significant main effects present for both condition (p = 0.016; g = 0.11-0.23) and load (p < 0.001; g = 0.42-1.6), but there was no statistically significant condition x time interaction effect (p = 0.101). • Post hoc analysis indicated that there was a significant difference between MV (p = 0.006) and PV (p = 0.032) between the traditional and 100% AEL conditions. • Moderate effect sizes were found with MV between the traditional and 100% AEL conditions at both 70% CON (g = 0.55) and 80% CON (g = 0.70). • No practically significant differences were found for PV.

Radon (222rn) As Tracer For Submarine Groundwater Discharge Investigation—Limitations Of The Approach At Shallow Wind-Exposed Coastal Settings, Michael Schubert, Jan Scholten, Matthias Kreuzburg, Eric Petermann, Mariele Lopes De Paiva, Dennis Kohler, V. Liebetrau, John Rapaglia, Michael Schlüter

Biology Faculty Publications

Mapping radon (222Rn) distribution patterns in the coastal sea is a widely applied method for localizing and quantifying submarine groundwater discharge (SGD). While the literature reports a wide range of successful case studies, methodical problems that might occur in shallow wind-exposed coastal settings are generally neglected. This paper evaluates causes and effects that resulted in a failure of the radon approach at a distinct shallow wind-exposed location in the Baltic Sea. Based on a simple radon mass balance model, we discuss the effect of both wind speed and wind direction as causal for this failure. We show that at coastal …

Impact Of Sleep And Training On Game Performance And Injury In Division-1 Women’S Basketball Amidst The Pandemic, Samah Senbel, S. Sharma, S. M. Raval, Christopher B. Taber, Julie K. Nolan, N. S. Artan, Diala Ezzeddine, Kaya Tolga

School of Computer Science & Engineering Faculty Publications

We investigated the impact of sleep and training load of Division - 1 women’s basketball players on their game performance and injury prediction using machine learning algorithms. The data was collected during a pandemic-condensed season with unpredictable interruptions to the games and athletic training schedules. We collected data from sleep monitoring devices, training data from coaches, injury reports from medical staff, and weekly survey data from athletes for 22 weeks.With proper data imputation, interpretable feature set, data balancing, and classifiers, we showed that we could predict game performance and injuries with more than 90% accuracy. More importantly, our F1 and …

A Comparative Test Of Creative Thinking In Preschool Children And Dolphins, Dawn Melzer, Deirdre Yeater, Madison Bradley, Heather M. Hill, Gonzalo Guerra, Kimberly Salazar, Teresa Bolton, Kathleen M. Dudzinski

Psychology Faculty Publications

Creativity is considered one aspect of intelligence. Including creativity allows for more room for expression (e.g., participants can respond with movement instead of written or verbal responses) than in standard intelligence assessments. The Torrance Tests of Creative Thinking (TTCT; Torrance, 1974) are the leading method of assessing creative abilities in school-aged humans and above. To assess creativity in young humans and nonhuman animals, modifications must be made to facilitate nonverbal responses. In the current study, a cross-species comparison was conducted between preschoolers and bottlenose dolphins to examine responses to a modified creativity task in which both species were trained to …

How Birds During Migration Maintain (Oxidative) Balance, Scott R. Mcwilliams, Wales A. Carter, Clara Cooper-Mullin, Kristen J. Demoranville, Abigail E. Frawley, Barbara J. Pierce, Megan Skrip

Biology Faculty Publications

Animals dynamically adjust their physiology and behavior to survive in changing environments, and seasonal migration is one life stage that demonstrates these dynamic adjustments. As birds migrate between breeding and wintering areas, they incur physiological demands that challenge their antioxidant system. Migrating birds presumably respond to these oxidative challenges by up-regulating protective endogenous systems or accumulating dietary antioxidants at stopover sites, although our understanding of the pre-migration preparations and mid-migration responses of birds to such oxidative challenges is as yet incomplete. Here we review evidence from field and captive-bird studies that address the following questions: (1) Do migratory birds build …

Epoc Comparison Between Resistance Training And High-Intensity Interval Training In Aerobically Fit Women, Beau K. Greer, Julie O'Brien, Lyndsey Hornbuckle, Lynn B. Panton

Exercise Science Faculty Publications

Previous research has shown that various modes of exercise may elicit significant increases in resting metabolism for up to 24 hours post-exercise, but typically using untrained or moderately active subjects. The purpose of the present study was to compare excess post-exercise oxygen consumption (EPOC) between circuit-style resistance training (RT) and high-intensity interval training (HIIT) in young, aerobically fit women. During the follicular phase of the menstrual cycle, seven participants reported to the laboratory for evening and morning baseline resting metabolic rate (RMR) measurements via indirect calorimetry. Participants fasted and slept overnight in the laboratory between RMR measurements. Following the morning …

Euadb: A Resource For Covid-19 Test Development And Comparison, Alyssa Woronik, Henry W. Shaffer, Karin Kiontke, Jon M. Laurent, Ronald Zambrano, Mariah Daley, Jef D. Boeke, David H. Fitch

Biology Faculty Publications

Due to the sheer number of COVID-19 (coronavirus disease 2019) cases there is a need for increased world-wide SARS-CoV-2 testing capability that is both efficient and effective. Having open and easy access to detailed information about these tests, their sensitivity, the types of samples they use, etc. would be highly useful to ensure their reproducibility, to help clients compare and decide which tests would be best suited for their applications, and to avoid costs of reinventing similar or identical tests. Additionally, this resource would provide a means of comparing the many innovative diagnostic tools that are currently being developed in …

Synergy Between Behavioural Research On Beluga Whales (Delphinapterus Leucas) Conducted In Zoological And Wild Settings, Heather Manitzas Hill, Deirdre Yeater, Michael Noonan

Psychology Faculty Publications

Behavioural observations of captive beluga whales have complemented and extended much of what has been learnt about this species in the wild. Aquarium-based research has provided finer-scale specificity for many topics, including the seasonal breeding pattern that is characteristic of this species, as well as socio-sexual behaviour that appears to be an important part of the behavioural repertoire of this species. One example is a strong propensity for male–male social interactions that begin to develop at an early age. In addition, detailed behavioural milestones in calves have been documented in ways that extend that which have been collected from wild …

Postactivation Potentiation Improves Jumps Performance In Children Ages 6 To 8 Years Old, Camila Gerber, Paolo Sirieiro, Igor Nasser, Christopher B. Taber, Humberto Miranda

Exercise Science Faculty Publications

Introduction: The aim of the present study was to investigate the effects of postactivation potentiation (PAP) in vertical and horizontal jump performance in pre-pubertal children.

Material and method: One hundred and nineteen children (65 girls and 54 boys; 6.8 ± 0.7 years old; 124.5 ± 6.4 cm; 25.2 ± 5.1 kg) participated in this study. This was a transversal cross-sectional study which incorporated a within-subjects repeated-measures design, where participants completed all protocols. The experimental procedure required four total testing, separated by one week, using a counterbalanced. This study investigated jumping performance associated with weighted jumps, low-load vertical jumps, and …

Preliminary Investigation Into The Effect Of Actn3 And Ace Polymorphisms On Muscle And Performance Characteristics, John P. Wagle, Kevin M. Carroll, Aaron J. Cunanan, Alexander Wetmore, Christopher Taber, Brad H. Deweese, Kimitake Sato, Charles A. Stuart

Exercise Science Faculty Publications

Preliminary investigation into the effect of ACTN3 and ACE polymorphisms on muscle and performance characteristics. J Strength Cond Res XX(X): 000-000, 2018-The purpose of this investigation was to explore the phenotypic and performance outcomes associated with ACTN3 and ACE polymorphisms. Ten trained men (age = 25.8 ± 3.0 years, height = 183.3 ± 4.1 cm, body mass = 92.3 ± 9.3 kg, and back squat to body mass ratio = 1.8 ± 0.3) participated. Blood samples were analyzed to determine ACTN3 and ACE polymorphisms. Standing ultrasonography images of the vastus lateralis (VL) were collected to determine whole muscle cross-sectional area …