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2019

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Effects Of Alkyl-Substituted Aromatic Amines Of Polybenzoxazine On Friction And Wear Properties Of Brake Pads, Anun Wongpayakyotin Jan 2019

Effects Of Alkyl-Substituted Aromatic Amines Of Polybenzoxazine On Friction And Wear Properties Of Brake Pads, Anun Wongpayakyotin

Chulalongkorn University Theses and Dissertations (Chula ETD)

This work aims to study the effects of alkyl-substituted aromatic amines of polybenzoxazine resins used as binders of non-asbestos friction composite materials. Effects of thermosetting resins (BA-ot, BA-mt, BA-pt, BA-a, and BA-35x) used as a binder of friction composite materials on thermal stability, dynamic mechanical properties, mechanical properties, and tribological performances are investigated. The different chemical networks of polybenzoxazine resulting in differences in the crosslink density and glass transition temperature (Tg) of friction composite materials. The enhancement of crosslink density values of polybenzoxazine composites (F-BA-ot < F-BA-pt < F-BA-a < F-BA-mt < F-BA-35x) resulting to bind other ingredients stronger and more tightly. From the experiment, it can be concluded that the higher crosslink density will result in higher thermal and mechanical properties, lower friction coefficient, and lesser specific wear rate.


Environmental Health Needs Assessment Base On Priority Need Index Corresponding With Health Effects From Flood For Improving Local Government Action Plans: A Case Study Of Nakhon Si Thammarat Province, Thailand, Jariya Matrongduang Jan 2019

Environmental Health Needs Assessment Base On Priority Need Index Corresponding With Health Effects From Flood For Improving Local Government Action Plans: A Case Study Of Nakhon Si Thammarat Province, Thailand, Jariya Matrongduang

Chulalongkorn University Theses and Dissertations (Chula ETD)

Flooding is considered as one of disaster that affect more people than any other natural disaster. The effects of flooding are extremely dangerous in developing countries due to low level flood protection. Initiatives in the development of response to floods need to create responses and support from stakeholders to identify causes, decision makers and local solutions. However, there’s limited studies on environmental health needs assessment for local government flood response. The purposes of this study are access environmental health needs of flooding action plan among affected people and compare environmental health needs between people who have and non-have health related …


Inhibitory Effect Of Canine Amniotic Membrane Against Common Bacterial Pathogens Associated With Ulcerative Keratitis, Rajit Lohajaroensub Jan 2019

Inhibitory Effect Of Canine Amniotic Membrane Against Common Bacterial Pathogens Associated With Ulcerative Keratitis, Rajit Lohajaroensub

Chulalongkorn University Theses and Dissertations (Chula ETD)

Infectious ulcerative keratitis is one of the significant ocular diseases in dogs leading to aggressive damage of the cornea and possibly loss of vision. Canine amniotic membrane (CAM) transplant revealed satisfactory result in canine complicated ulcers. However, antimicrobial activity of CAM has not yet been elucidated. This study is to assess antimicrobial activities of fresh CAM on bacteria associated with ulcerative keratitis and to investigate antimicrobial peptide genes expression. A total of twenty-three CAMs from healthy puppies were collected. Nineteen CAMs were tested for antimicrobial activity by modified disk diffusion test. Four CAMS were tested for mRNA expression of antimicrobial …


Adsorption Of Iodo- And Bromo-Disinfection By-Products On Functionalized Metal Organic Frameworks, Phacharapol Induvesa Jan 2019

Adsorption Of Iodo- And Bromo-Disinfection By-Products On Functionalized Metal Organic Frameworks, Phacharapol Induvesa

Chulalongkorn University Theses and Dissertations (Chula ETD)

The adsorptive mechanisms and the effects of two different thiol modification methods on the removal of five iodinated trihalomethanes (I-THMs) by two types of metal-organic frameworks (MOFs) (e.g., ZIF-8 and HKUST-1) were investigated in this study. The direct post-grafting of dithioglycol to the metal complex node (Zn and Cu) of ZIF-8 (ZF-SH), HKUST-1 (HK-SH), can increase the mesopore structures and the active functional group, which is a critical property required for excellent adsorption of I-THMs. Besides, grafting with the (3-mercaptopropyl)-trimethoxy functional group on ZIF-8 (ZF-Si-SH) and HKUST-1 (HK-MPTS) provided lower active thiol functional group and caused the steric effect for …


นวัตกรรมระบบประเมินความสามารถในการแข่งขันของวิสาหกิจไทยในอุตสาหกรรมอาหาร, สุทธินันท์ รัตนโชติถาวร Jan 2019

นวัตกรรมระบบประเมินความสามารถในการแข่งขันของวิสาหกิจไทยในอุตสาหกรรมอาหาร, สุทธินันท์ รัตนโชติถาวร

Chulalongkorn University Theses and Dissertations (Chula ETD)

การศึกษางานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาปัจจัยที่ส่งผลต่อความสามารถในการแข่งขันของวิสาหกิจไทยในอุตสาหกรรมอาหาร การออกแบบและพัฒนานวัตกรรมระบบประเมินและการศึกษาการยอมรับนวัตกรรมระบบประเมินในเชิงพาณิชย์ โดยการวิจัยแบบผสานวิธี แบ่งออกเป็นการวิจัยเชิงคุณภาพด้วยการสัมภาษณ์ผู้เชี่ยวชาญ ด้วยวิธีการสุ่มแบบเจาะจง จำนวน 12 คน ร่วมกับการศึกษาข้อมูลเชิงปริมาณจากการสำรวจกลุ่มตัวอย่างด้วยแบบสอบถาม โดยวิธีการสุ่มตัวอย่างแบบหลายขั้นตอน จำนวน 333 คน มาจากกลุ่มตัวอย่างคือ สถานประกอบการของอุตสาหกรรมอาหารแปรรูปที่ผ่านการรับรองมาตรฐานสากลเพื่อการส่งออกจากหน่วยงานสังกัดกระทรวงเกษตรและสหกรณ์ และผลการวิเคราะห์องค์ประกอบเชิงยืนยันพบว่า ข้อมูลองค์ประกอบเชิงทฤษฎีมีความสอดคล้องกับข้อมูลเชิงประจักษ์ พิจารณาได้จากค่าไค-สแควร์มีค่าเท่ากับ 58.36 ซึ่งมีค่าความน่าจะเป็นเท่ากับ .253 ที่องศาอิสระเท่ากับ 52 และสัดส่วนของค่าไค-สแควร์ต่อองศาอิสระมีค่าเท่ากับ 1.12 ค่าดัชนีวัดระดับความกลมกลืนเท่ากับ 0.980 และค่าดัชนีวัดระดับความกลมกลืนที่ปรับแก้แล้วเท่ากับ 0.940 ซึ่งสอดคล้องกับค่าสถิติวัดความกลมกลืนจากค่าดัชนีวัดความกลมกลืนเปรียบเทียบมีค่าเท่ากับ 0.999 และสอดคล้องกับค่าความคลาดเคลื่อนในการประมาณค่าพารามิเตอร์ เท่ากับ 0.019 และการวิเคราะห์การถดถอยเชิงเส้นแบบพหุคูณสามารถตอบสมมติฐานของงานวิจัยได้ว่า ความสามารถทางนวัตกรรม ความสามารถทางการตลาด ความสามารถทางการจัดการและความสามารถเชิงพลวัตส่งผลทางบวกต่อความได้เปรียบทางการแข่งขันที่ยั่งยืนสำหรับวิสาหกิจไทยในอุตสาหกรรมอาหารแปรรูป ที่น้ำหนักสัมประสิทธิ์เท่ากับ 0.182, 0.170, 0.293, และ 0.329 ตามลำดับ และจึงนำปัจจัยดังกล่าวมาใช้ในการออกแบบและพัฒนานวัตกรรมระบบประเมินด้วยเทคนิค Machine Learning พบว่า ระบบประเมินฯมีความถูกต้องสูงที่ร้อยละ 93.34 และระดับการยอมรับการใช้งานระบบประเมินนี้สูงถึงร้อยละ 93.30 นอกจากนี้จากการศึกษาความเป็นไปได้ทางธรุกิจพบว่ารูปแบบการอนุญาตให้ใช้สิทธิแต่เพียงผู้เดียวมีความเหมาะสมมากที่สุด ด้วยระยะเวลาคืนทุนเท่ากับ 11 เดือน มูลค่าปัจจุบันสุทธิ เท่ากับ 154,669 บาท และอัตราผลตอบแทนเท่ากับ 36.03%


การเรียนรู้เชิงรุกผ่านเว็บไซต์เพื่อสร้างแผนธุรกิจนวัตกรรม: ผู้เรียนระดับปริญญาตรี, ศราวณี พึ่งผู้นำ Jan 2019

การเรียนรู้เชิงรุกผ่านเว็บไซต์เพื่อสร้างแผนธุรกิจนวัตกรรม: ผู้เรียนระดับปริญญาตรี, ศราวณี พึ่งผู้นำ

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อพัฒนาเว็บไซต์สำหรับเขียนแผนธุรกิจที่สนับสนุนนวัตกรรมสำหรับนักศึกษาระดับปริญญาตรี การเขียนแผนธุรกิจถือได้ว่าเป็นหนึ่งในกิจกรรมที่สำคัญของการเป็นผู้ประกอบการและมีความเกี่ยวข้องกับกิจกรรมหลักของการศึกษาระดับอุดมศึกษามากขึ้นเรื่อย ๆ ในการศึกษานี้ได้เสนอ Collaborative Website ชื่อ BRAINY Business Model การศึกษาข้อมูลเชิงปริมาณจากแบบสอบถามของนักศึกษาระดับปริญญาตรี 432 คน (นักศึกษาชั้นปีที่ 3 และปีที่ 4 จาก 11 มหาวิทยาลัยในประเทศไทย) ในแง่ของเนื้อหาต่างๆ และการเข้าใช้ระบบ ผู้ใช้ต้องการจะสามารถเข้าใช้งานเว็บไซต์ได้โดยไม่ต้องจ่ายเงินในระดับสูงสุด (Mean = 4.375, S.D. = 1.003) และข้อมูลเชิงคุณภาพจากการสัมภาษณ์กลุ่มเป้าหมาย (นักศึกษาระดับปริญญาตรี 11 คน ซึ่งมีประสบการณ์ในการแข่งขันแผนธุรกิจ) พบว่า มีความสนใจใช้เว็บไซต์นี้ ผลการวิจัยยังชี้ให้เห็นถึงความต้องการในการเข้าถึงเว็บไซต์โดยมีระบบความปลอดภัย และต้องการดูวิดีโอสั้นๆ จุดเด่นของระบบนี้คือการเพิ่มเครื่องมือที่ช่วยให้นักเรียนมีความคิดสร้างสรรค์ในการค้นหานวัตกรรมซึ่งก็คือ TRIZ ที่ให้แนวทางเชิงตรรกะในการพัฒนาความคิดสร้างสรรค์สำหรับนวัตกรรมและการแก้ปัญหา ในส่วนของการทดลองใช้เว็บไซต์นี้ ผู้วิจัยใช้รูปแบบกึ่งทดลอง แบ่งผู้เรียนเป็น 2 กลุ่ม คือ กลุ่มทดลองที่ได้ใช้เว็บไซต์นี้ และกลุ่มควบคุมที่ใช้เว็บไซต์อื่น ผลการทดสอบสมมติฐาน พบว่า กลุ่มทดลองมีคะแนนในด้านต่างๆ สูงกว่ากลุ่มควบคุมอย่างมีนัยสำคัญทางสถิติ ได้แก่ ด้านระดับความใหม่ของผลิตภัณฑ์ ความคิดสร้างสรรค์ ความเกี่ยวข้องสอดคล้องกับ Theme งาน คือ เรื่องเกี่ยวกับผลิตภัณฑ์ใหม่ที่จะตอบสนองแนวโน้มที่เกิดในสังคมได้ และความถูกต้องทางวิชาการ ส่วนด้านเชิงพาณิชย์ ไม่มีนัยสำคัญทางสถิติ และจากการศึกษาความเป็นไปได้ทางการเงินของการลงทุนผลิตระบบนวัตกรรมนี้มีค่า NPV เท่ากับ 1,990,434.49 บาท IRR เท่ากับ 47.86% และระยะเวลาคืนทุน 2 ปี 4 เดือน


Salivary Proteomic Analysis For Detection And Monitoring Treatment Response In Canine Oral Tumors, Sekkarin Ploypetch Jan 2019

Salivary Proteomic Analysis For Detection And Monitoring Treatment Response In Canine Oral Tumors, Sekkarin Ploypetch

Chulalongkorn University Theses and Dissertations (Chula ETD)

Tumors of the oral cavity account for 8% of all canine neoplasia. Malignant oral mass such as melanoma, oral squamous cell carcinoma (OSCC) and fibrosarcoma covers approximately 59% of canine oral neoplasia. Among these, canine oral melanoma (COM) is the most common oral tumors in dogs, with approximately 30–40% of all oral tumors. With high recurrence and/or distant metastasis rate, biomarkers are required for early detection, diagnosis, prognosis, and monitoring treatment response. Since saliva directly contacts tumors and saliva collection is non-invasive, easily accessible and cost effective, salivary biomarkers are suitable to support the evaluation of oral diseases. This study …


Eigenstates Transition Without Undergoing An Adiabatic Process, Fatemeh Mostafavi, Luqi Yuan, Hamidreza Ramezani Jan 2019

Eigenstates Transition Without Undergoing An Adiabatic Process, Fatemeh Mostafavi, Luqi Yuan, Hamidreza Ramezani

Physics & Astronomy Faculty Publications

We introduce a class of non-Hermitian Hamiltonians that offers a dynamical approach to a shortcut to adiabaticity (DASA). In particular, in our proposed 2 × 2 Hamiltonians, one eigenvalue is absolutely real and the other one is complex. This specific form of eigenvalues helps us to exponentially decay the population in an undesired eigenfunction or amplify the population in the desired state while keeping the probability amplitude in the other eigenfunction conserved. This provides us with a powerful method to have a diabatic process with the same outcome as its corresponding adiabatic process. In contrast to standard shortcuts to adiabaticity, …


Narrow-Band Search For Gravitational Waves From Known Pulsars Using The Second Ligo Observing Run, B. P. Abbott, B. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, D. Tuyenbayev, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, A. K. Zadrozny Jan 2019

Narrow-Band Search For Gravitational Waves From Known Pulsars Using The Second Ligo Observing Run, B. P. Abbott, B. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, D. Tuyenbayev, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, A. K. Zadrozny

Physics & Astronomy Faculty Publications

Isolated spinning neutron stars, asymmetric with respect to their rotation axis, are expected to be sources of continuous gravitational waves. The most sensitive searches for these sources are based on accurate matched filtering techniques that assume the continuous wave to be phase locked with the pulsar beamed emission. While matched filtering maximizes the search sensitivity, a significant signal-to-noise ratio loss will happen in the case of a mismatch between the assumed and the true signal phase evolution. Narrowband algorithms allow for a small mismatch in the frequency and spin-down values of the pulsar while coherently integrating the entire dataset. In …


Constraining The P-Mode–G-Mode Tidal Instability With Gw170817, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, D. Tuyenbayev, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Robert Stone, W. H. Wang Jan 2019

Constraining The P-Mode–G-Mode Tidal Instability With Gw170817, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, D. Tuyenbayev, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Robert Stone, W. H. Wang

Physics & Astronomy Faculty Publications

We analyze the impact of a proposed tidal instability coupling p modes and g modes within neutron stars on GW170817. This nonresonant instability transfers energy fromthe orbit of the binary to internal modes of the stars, accelerating the gravitational-wave driven inspiral.We model the impact of this instability on the phasing of the gravitational wave signal using three parameters per star: an overall amplitude, a saturation frequency, and a spectral index. Incorporating these additional parameters, we compute the Bayes factor (lnBpg !pg) comparing our p-g model to a standard one. We find that the observed signal is consistent with waveform models …


A Psychometric Analysis Of The Social Anxiety Scale For Adolescents Among Youth With Autism Spectrum Disorder: Caregiver–Adolescent Agreement, Factor Structure, And Validity, Hillary Schiltz, Brooke E. Magnus, Alana J. Mcvey, Angela Haendel, Bridget Dolan, Rachel E. Stanley, Kirsten S. Willar, Sheryl Pleiss, Audrey Meyer Carson, Mary E. Carlson, Christina Murphy, Elisabeth M. Vogt, Brianna D. Yund, Amy V. Van Hecke Jan 2019

A Psychometric Analysis Of The Social Anxiety Scale For Adolescents Among Youth With Autism Spectrum Disorder: Caregiver–Adolescent Agreement, Factor Structure, And Validity, Hillary Schiltz, Brooke E. Magnus, Alana J. Mcvey, Angela Haendel, Bridget Dolan, Rachel E. Stanley, Kirsten S. Willar, Sheryl Pleiss, Audrey Meyer Carson, Mary E. Carlson, Christina Murphy, Elisabeth M. Vogt, Brianna D. Yund, Amy V. Van Hecke

College of Education Faculty Research and Publications

Social anxiety is common among adolescents with autism spectrum disorder (ASD). An ongoing challenge for both research and clinical practice in ASD is the assessment of anxious symptomatology. Despite its widespread use in samples of youth with ASD, the Social Anxiety Scale for Adolescents (SAS-A) has not received psychometric evaluation within this population; thus, the validity of its use in research and clinical practice for ASD remains unclear. The present study conducted a psychometric analysis of caregiver and adolescent SAS-A forms in a sample of adolescents with ASD (N = 197). Results revealed (1) poor caregiver–adolescent item-level agreement, (2) …


Delivery, Facilitas, And Copia : Job Market Preparation And The Revival Of The Fifth Canon., Joseph Turner Jan 2019

Delivery, Facilitas, And Copia : Job Market Preparation And The Revival Of The Fifth Canon., Joseph Turner

Faculty and Staff Scholarship

This essay argues that English Studies departments should implement training programs in oral delivery strategies for graduate students seeking tenure track employment. A sample a 13-week training program, modeled on elements of classical rhetorical pedagogy, can help students develop and refine stills in oral delivery necessary for academic job interviews.


Can A Precast Pit Latrine Concrete Floor Withstand Emptying Operations? An Investigation From Malawi., Joshua Mchenga, Rochelle H. Holm Jan 2019

Can A Precast Pit Latrine Concrete Floor Withstand Emptying Operations? An Investigation From Malawi., Joshua Mchenga, Rochelle H. Holm

Faculty and Staff Scholarship

For fecal sludge from households in low- and middle-income countries to be treated offsite it needs to be removed, which can be greatly affected by the pit latrine floor design. However, it is unclear whether precast pit latrine concrete floors (latrine slabs) can withstand emptiers and their equipment. To investigate this issue, 28 prefabricated latrine slabs were purchased in two cities of Malawi. They were first visually evaluated, and then their compression strength was tested. Additionally, each seller was asked a series of questions to better understand their business, training, and construction practices. Results showed that households should perform due …


Connections Between Pre-Service Teachers’ Mathematical Dispositions And Self-Efficacy For Teaching Mathematics, Jasmine M. Cruz, Aaron T. Wilson, Xiaohui Wang Jan 2019

Connections Between Pre-Service Teachers’ Mathematical Dispositions And Self-Efficacy For Teaching Mathematics, Jasmine M. Cruz, Aaron T. Wilson, Xiaohui Wang

School of Mathematical & Statistical Sciences Faculty Publications

Mathematical dispositions (MD) and self-efficacy for teaching mathematics (SEFTM) are important elements of teachers‟ beliefs that significantly influence their behaviors and educational practices in the classroom. This study looked at relationships between pre-service teachers‟ (PSTs) MD and their SEFTM in connection with other descriptors related to their progress through the teacher education program and prior mathematical experiences. Survey data were collected from 238 PSTs at a midsized university in the US. Results include the finding that PSTs‟ intended grade-level and subject approximately mirror their MD and SEFTM: those planning to be elementary school (generalist) teachers were slightly behind both middle …


Properties Of The Binary Neutron Star Merger Gw170817, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Robert Stone, Darkhan Tuyenbayev, Wenhui Wang Jan 2019

Properties Of The Binary Neutron Star Merger Gw170817, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, Robert Stone, Darkhan Tuyenbayev, Wenhui Wang

Physics & Astronomy Faculty Publications

On August 17, 2017, the Advanced LIGO and Advanced Virgo gravitational-wave detectors observed a low-mass compact binary inspiral. The initial sky localization of the source of the gravitational-wave signal, GW170817, allowed electromagnetic observatories to identify NGC 4993 as the host galaxy. In this work, we improve initial estimates of the binary's properties, including component masses, spins, and tidal parameters, using the known source location, improved modeling, and recalibrated Virgo data. We extend the range of gravitational-wave frequencies considered down to 23 Hz, compared to 30 Hz in the initial analysis. We also compare results inferred using several signal models, which …


Black Bear Use Of Forest Roads In Western Washington, Gary W. Witmer Jan 2019

Black Bear Use Of Forest Roads In Western Washington, Gary W. Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

Radiolocations (108) of 20 black bears were used to assess use or avoidance of 3 forest road types in western Washington. Distances of bears to each type of road were compared to distances of 108 random points using t-tests. Females and males avoided 2-lane roads, while only males avoided 1-lane roads, the most common road type in the area. Females, but not males, were located closer to overgrown, spur roads than expected. This road type has substantial cover of grasses, forbs, and berry-producing shrubs along with protective tree cover. This situation may provide easy travel for females along with security …


No Detection Of Brodifacoum Residues In The Marine And Terrestrial Food Web Three Years After Rat Eradication At Palmyra Atoll, Central Pacific, A. Wegmann, G. Howald, S. Kropidlowski, N. Holmes, A.B. Shiels Jan 2019

No Detection Of Brodifacoum Residues In The Marine And Terrestrial Food Web Three Years After Rat Eradication At Palmyra Atoll, Central Pacific, A. Wegmann, G. Howald, S. Kropidlowski, N. Holmes, A.B. Shiels

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive alien species represent one of the greatest threats to native plants and animals on islands. Rats (Rattus spp.) have invaded most of the world’s oceanic islands, causing lasting or irreversible damage to ecosystems and biodiversity. To counter this threat, techniques to eradicate invasive rats from islands have been developed and applied across the globe. Eradication of alien rats from large or complex island ecosystems has only been successful with the use of bait containing a rodenticide. While effective at eradicating rats from islands, rodenticide can persist in the ecosystem longer than the time required to eradicate the target rat …


Home Range And Habitat Use Of West Virginia Canis Latrans (Coyote), Lauren M. Mastro, Dana J. Morin, Eric M. Gese Jan 2019

Home Range And Habitat Use Of West Virginia Canis Latrans (Coyote), Lauren M. Mastro, Dana J. Morin, Eric M. Gese

United States Department of Agriculture Wildlife Services: Staff Publications

Canis latrans (Coyote) has undergone a range expansion in the United States over the last century. As a highly opportunistic species, its home range and habitat use changes with ecological context. Coyotes were first reported in West Virginia in 1950 but were not commonly observed until the 1990s, and there is scant information on Coyotes in the region. We used telemetry data from 8 radiocollared Coyotes in West Virginia to estimate home-range size and third-order habitat selection. Home-range areas (95% utilization distributions; UDs) varied from 5.22 to 27.79 km2 (mean = 12.48 ± 2.61 km2), with highly concentrated use of …


Carrion Availability In Space And Time, Marcos Moleón, Nuria Selva, David M. Bailey, David M. Bailey, Ainara Cortés-Avizanda, Travis L. Devault Jan 2019

Carrion Availability In Space And Time, Marcos Moleón, Nuria Selva, David M. Bailey, David M. Bailey, Ainara Cortés-Avizanda, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Introduction

Availability of carrion to scavengers is a central issue in carrion ecology and management, and is crucial for understanding the evolution of scavenging behaviour. Compared to live animals, their carcasses are relatively unpredictable in space and time in natural conditions, with a few exceptions (see below, especially Sect. “Carrion Exchange at the Terrestrial-Aquatic Interface”). Carrion is also an ephemeral food resource due to the action of a plethora of consumers, from microorganisms to large vertebrates, as well as to desiccation (i.e., loss of water content; DeVault et al. 2003; Beasley et al. 2012; Barton et al. 2013; Moleón et …


Ecological Functions Of Vertebrate Scavenging, James C. Beasley, Zachary H. Olson, Nuria Selva, Travis L. Devault Jan 2019

Ecological Functions Of Vertebrate Scavenging, James C. Beasley, Zachary H. Olson, Nuria Selva, Travis L. Devault

United States Department of Agriculture Wildlife Services: Staff Publications

Introduction

The role of vertebrate scavenging in food web dynamics has historically been minimalized and portrayed as the activity of a select group of obligate scavengers (e.g., vultures), with a simplistic linkage between carrion and detritivores in food webs. Research in the last few decades, however, has revealed that the role of carrion in food web dynamics is severely underestimated, highly complex, and pervasive among ecosystems across the globe (DeVault et al. 2003; Selva and Fortuna 2007; Wilson and Wolkovich 2011). Such observations have led to a surge in research interest in scavenging ecology that continues to reveal new information …


Locally Fixed Alleles: A Method To Localize Gene Drive To Island Populations, Jaye Sudweeks, Brandon Hollingsworth, Dimitri V. Blondel, Karl J. Campbell, Sumit Dhole, John D. Eisemann, Owain Edwards, John Godwin, Gregg R. Howald, Kevin P. Oh, Antoinette J. Piaggio, Thomas A.A. Prowse, Joshua V. Ross, J. Royden Saah, Aaron B. Shiels, Paul Q. Thomas, David W. Threadgill, Michael R. Vella, Fred Gould, Alun L. Lloyd Jan 2019

Locally Fixed Alleles: A Method To Localize Gene Drive To Island Populations, Jaye Sudweeks, Brandon Hollingsworth, Dimitri V. Blondel, Karl J. Campbell, Sumit Dhole, John D. Eisemann, Owain Edwards, John Godwin, Gregg R. Howald, Kevin P. Oh, Antoinette J. Piaggio, Thomas A.A. Prowse, Joshua V. Ross, J. Royden Saah, Aaron B. Shiels, Paul Q. Thomas, David W. Threadgill, Michael R. Vella, Fred Gould, Alun L. Lloyd

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive species pose a major threat to biodiversity on islands. While successes have been achieved using traditional removal methods, such as toxicants aimed at rodents, these approaches have limitations and various off-target effects on island ecosystems. Gene drive technologies designed to eliminate a population provide an alternative approach, but the potential for drive-bearing individuals to escape from the target release area and impact populations elsewhere is a major concern. Here we propose the “Locally Fixed Alleles” approach as a novel means for localizing elimination by a drive to an island population that exhibits significant genetic isolation from neighboring populations. Our …


Comparing Live-Capture Methods For Nutria: Single- Versus Multiple-Capture Cage Traps, Trevor R. Sheffels, Mark D. Sytsma, Jacoby Carter, Jimmy D. Taylor Jan 2019

Comparing Live-Capture Methods For Nutria: Single- Versus Multiple-Capture Cage Traps, Trevor R. Sheffels, Mark D. Sytsma, Jacoby Carter, Jimmy D. Taylor

United States Department of Agriculture Wildlife Services: Staff Publications

Herbivory and burrowing by nutria (Myocastor coypus) cause substantial ecological and economic damage. Trapping is a common, effective practice for reducing nutria damage; however, trapping approaches must continually be adapted to keep pace with evolving animal welfare and ethical issues and to more effectively target pest species of interest. Our objective was to evaluate the efficacy of 2 nonlethal trap types for nutria: single-capture (SCT) and multi-capture (MCT) cage traps. We established 3 MCTs and 3 SCTs at each of 7 sites on a 10,500-ha mixed-use island located 15 km northwest of Portland, Oregon, USA. We pre-baited using carrots, apples, …


Biology And Impacts Of Pacific Island Invasive Species. 15. Psittacula Krameri, The Rose-Ringed Parakeet (Psittaciformes: Psittacidae)1, Aaron B. Shiels, Nicholas P. Kalodimos Jan 2019

Biology And Impacts Of Pacific Island Invasive Species. 15. Psittacula Krameri, The Rose-Ringed Parakeet (Psittaciformes: Psittacidae)1, Aaron B. Shiels, Nicholas P. Kalodimos

United States Department of Agriculture Wildlife Services: Staff Publications

The rose-ringed parakeet (RRP), Psittacula krameri, has become established in at least four Pacific Island countries (Hong Kong China, Japan, New Zealand, U.S.A.), including the Hawaiian islands of Kaua‘i, O‘ahu, and Hawai‘i. Most Pacific islands are at risk of RRP colonization. This species was first introduced to Hong Kong in 1903 and Hawai‘i in the 1930s–1960s, established since 1969 in Japan, and in New Zealand since 2005 where it has repeatedly established after organized removals. The founding birds were imported cage-birds from the pet trade. In native India, RRP are generally found associated with human habitation and are considered a …


Evaluation Of Two Unmanned Aircraft Systems As Tools For Protecting Crops From Blackbird Damage, Lucas J. Wandrie, Page E. Klug, Mark E. Clark Jan 2019

Evaluation Of Two Unmanned Aircraft Systems As Tools For Protecting Crops From Blackbird Damage, Lucas J. Wandrie, Page E. Klug, Mark E. Clark

United States Department of Agriculture Wildlife Services: Staff Publications

In response to a need for mitigating blackbird damage to crops, we evaluated the effectiveness of two unmanned aircraft systems (UAS or drones) to protect crops from blackbird damage. UAS are known to elicit behavioral and physiological responses in wildlife and have been proposed as a means to protect row crop agriculture from avian pest depredation. We evaluated the behavioral responses of captive and free-ranging red-winged blackbirds to a fixed-wing and a rotary-wing (multi-rotor, quadcopter) UAS by comparing preflight behaviors to behaviors during UAS approach. Due to the flight limitations of the respective UAS, the fixed-wing and rotarywing were evaluated …


Effects Of Repeated Sublethal External Exposure To Deep Water Horizon Oil On The Avian Metabolome, Brian S. Dorr, Katie C. Hanson-Dorr, Fariba M. Assadi-Porter, Ebru Selin Selen, Katherine A. Healy, Katherine E. Horak Jan 2019

Effects Of Repeated Sublethal External Exposure To Deep Water Horizon Oil On The Avian Metabolome, Brian S. Dorr, Katie C. Hanson-Dorr, Fariba M. Assadi-Porter, Ebru Selin Selen, Katherine A. Healy, Katherine E. Horak

United States Department of Agriculture Wildlife Services: Staff Publications

We assessed adverse effects of external sublethal exposure of Deepwater Horizon, Mississippi Canyon 252 oil on plasma and liver metabolome profiles of the double-crested cormorant (Phalacrocorax auritus), a large (1.5 to 3.0 kg) diving waterbird common in the Gulf of Mexico. Metabolomics analysis of avian plasma showed significant negative effects on avian metabolic profiles, in some cases after only two external exposures (26 g cumulative) to oil. We observed significant (p < 0.05) changes in intermediate metabolites of energy metabolism and fatty acid and amino acid metabolic pathways in cormorants after repeated exposure to oil. Exposure to oil increased several metabolites (glycine, betaine, serine and methionine) that are essential to the one-carbon metabolism pathway. Lipid metabolism was affected, causing an increase in production of ketone bodies, suggesting lipids were used as an alternative energy source for energy production in oil exposed birds. In addition, metabolites associated with hepatic bile acid metabolism were affected by oil exposure which was correlated with changes observed in bile acids in exposed birds. These changes at the most basic level of phenotypic expression caused by sublethal exposure to oil can have effects that would be detrimental to reproduction, migration, and survival in avian species.


Wildlife Management Practices Associated With Pathogen Exposure In Non-Nativewild Pigs In Florida, U.S., Amanda N. Carr, Michael P. Milleson, Felipe A. Hernandez, Hunter R. Merrill, Michael L. Avery, Samantha M. Wisely Jan 2019

Wildlife Management Practices Associated With Pathogen Exposure In Non-Nativewild Pigs In Florida, U.S., Amanda N. Carr, Michael P. Milleson, Felipe A. Hernandez, Hunter R. Merrill, Michael L. Avery, Samantha M. Wisely

United States Department of Agriculture Wildlife Services: Staff Publications

Land use influences disease emergence by changing the ecological dynamics of humans, wildlife, domestic animals, and pathogens. This is a central tenet of One Health, and one that is gaining momentum in wildlife management decision-making in the United States. Using almost 2000 serological samples collected from non-native wild pigs (Sus scrofa) throughout Florida (U.S.), we compared the prevalence and exposure risk of two directly transmitted pathogens, pseudorabies virus (PrV) and Brucella spp., to test the hypothesis that disease emergence would be positively correlated with one of the most basic wildlife management operations: Hunting. The seroprevalence of PrV- …


American White Pelican (Pelecanus Erythrorhynchos) Growth, Nutrition And Immunology, Treena L. Ferguson, Brian J. Rude, D. Tommy King Jan 2019

American White Pelican (Pelecanus Erythrorhynchos) Growth, Nutrition And Immunology, Treena L. Ferguson, Brian J. Rude, D. Tommy King

United States Department of Agriculture Wildlife Services: Staff Publications

Limited information about nutrition exists on American White Pelicans (Pelecanus erythrorhynchos) from hatching to fledging. To detail immunity, metabolism and nutrition of juvenile American White Pelicans, during 22-23 July 2011, 103 samples of regurgitate matter were collected at five Chase Lake, North Dakota, USA, and three Bitter Lake, South Dakota, USA, sub-colonies. Regurgitate sample nutrient content was significantly different for organic matter (P = 0.012), crude protein (P = 0.001), neutral detergent fiber (P = 0.014), acid detergent fiber (P = 0.005) and energy (P = 0.034) between North (n = 5) …


Using Dna To Identify The Source Of Invasive Mongooses, Herpestes Auropunctatus (Carnivora: Herpestidae) Captured On Kaua‘I, Hawaiian Islands, Darren J. Wostenberg, Matthew W. Hopken, Aaron B. Shiels, Antoinette J. Piaggio Jan 2019

Using Dna To Identify The Source Of Invasive Mongooses, Herpestes Auropunctatus (Carnivora: Herpestidae) Captured On Kaua‘I, Hawaiian Islands, Darren J. Wostenberg, Matthew W. Hopken, Aaron B. Shiels, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Two small Indian mongooses (Herpestes auropunctatus) were live-captured in 2012 at separate locations on the Hawaiian Island of Kaua'i, which was previously considered to be free of this invasive species. Genotypes from these two individuals were compared to genotypes of H. auropunctatus from the islands of Hawai'i (n =39), O'ahu (n =91), Maui (n = 39), and Moloka'i (n = 19) to determine the island of origin of the Kaua'i individuals. Genotypes were generated from each individual using five microsatellite loci. Genetic clustering was estimated by Bayesian inference of spatial clustering of individuals and …


Cause‐Specific Mortality Of The World’S Terrestrial Vertebrates, Jacob E. Hill, Travis L. Devault, Jerrold L. Belant Jan 2019

Cause‐Specific Mortality Of The World’S Terrestrial Vertebrates, Jacob E. Hill, Travis L. Devault, Jerrold L. Belant

United States Department of Agriculture Wildlife Services: Staff Publications

Aim: Vertebrates are declining worldwide, yet a comprehensive examination of the sources of mortality is lacking. We conducted a global synthesis of terrestrial vertebrate cause‐specific mortality to compare the sources of mortality across taxa and determine predictors of susceptibility to these sources of mortality.

Location: Worldwide.

Time period: 1970–2018.

Major taxa studied: Mammals, birds, reptiles and amphibians.

Methods: We searched for studies that used telemetry to determine the cause of death of terrestrial vertebrates. We determined whether each mortality was caused by anthropogenic or natural sources and further classified mortalities within these two categories (e.g. harvest, vehicle collision and predation). …


In Situ Evaluation Of An Automated Aerial Bait Delivery System For Landscape-Scale Control Of Invasive Brown Treesnakes On Guam, Shane Siers, Will Pitt, John Eisemann, Larry Clark, Aaron B. Shiels, C. S. Clark, R. J. Gosnell, M. C. Messaros Jan 2019

In Situ Evaluation Of An Automated Aerial Bait Delivery System For Landscape-Scale Control Of Invasive Brown Treesnakes On Guam, Shane Siers, Will Pitt, John Eisemann, Larry Clark, Aaron B. Shiels, C. S. Clark, R. J. Gosnell, M. C. Messaros

United States Department of Agriculture Wildlife Services: Staff Publications

After decades of biodiversity loss and economic burden caused by the brown treesnake invasion on the Pacific island of Guam, relief hovers on the horizon. Previous work by USDA Wildlife Services (WS) and its National Wildlife Research Center (NWRC) demonstrated that brown treesnake numbers in forested habitats can be dramatically suppressed by aerial delivery of dead newborn mouse (DNM) baits treated with 80 mg of acetaminophen. However, manual bait preparation and application is impractical for landscape-scale treatment. WS, NWRC, and the US Department of the Interior have collaborated with Applied Design Corporation to engineer an automated bait manufacturing and delivery …