Young’s Modulus: Building a Device to Measure Material Strength to Understand Interatomic Bond Stiffness

Young’s Modulus is an equation that is to measure the strength in different materials. A common application of Young’s Modulus is measuring the breaking point of cables. The understanding of the Young’s Modulus equation and its applications is a standard part of the introductory undergraduate physics sequence. We sought to construct a lab apparatus that would enable physics undergraduate students to measure and verify the results of the Young’s Modulus equation. These macroscopic measurements can then be used to further understand inter-atomic bond stiffness. This poster reviews the design, construction, and testing of a Young’s Modulus lab experiment. This lab will be used by undergraduate students at Northwestern College, thus offering a further experimental application of a topic that was previously taught only theoretically.

Designing and Building an Inverted Microscope

Iowa Stonybrook Lasers And DNA Course Embedded Research (ISLAND CURE) is a new research collaboration group that is focused on undergraduate research for both the students and the professors. The goal of this research collaboration was to create physics apparatuses to make biochemical measurements. One of the tools we are developing is an infrared optical tweezing system. This requires an inverted microscope to facilitate the trap. To observe one of these measurements, an inverted microscope is required to observe the sample. Inverted microscopes can be expensive, and our budget is limited. To overcome this issue, our research group decided to create our own inverted microscope with the minimal budget we had. This microscope can now be used for optical tweezing and observation of a live sample

Building a Mach Zehnder Interferometer with Limited Resources

Interferometers are simple optical devices that function by splitting a coherent light beam. The beam is recombined using beam splitters and mirrors. The addition of the two light beams produces interference patterns in the forms of fringes which can be used to study the path taken by the two beams. This is old technology and we sought to construct an interferometer using rudimentary and cast-off equipment. The purpose is to show that modern physics concepts can be measured inexpensively and by undergraduate student design. Though we had no optics table and or optical mounts, by careful alignment and adjustments to the equipment, we were able to produce fringes whose intensity could measure phase changes of a light beam as it goes through various mediums. We were able to determine and learn more about the properties of light and produce successful results. This demonstrates a method of introducing modern physics lab applications at a low cost

Mitigating the Effects of Au-Al Intermetallic Compounds Due to High-Temperature Processing of Surface Electrode Ion Traps

Stringent physical requirements need to be met for the high performing surface-electrode ion traps used in quantum computing, sensing, and timekeeping. In particular, these traps must survive a high temperature environment for vacuum chamber preparation and support high voltage rf on closely spaced electrodes. Due to the use of gold wire bonds on aluminum pads, intermetallic growth can lead to wire bond failure via breakage or high resistance, limiting the lifetime of a trap assembly to a single multi-day bake at 200$^{\circ}$C. Using traditional thick metal stacks to prevent intermetallic growth, however, can result in trap failure due to rf breakdown events. Through high temperature experiments we conclude that an ideal metal stack for ion traps is Ti20nm/Pt100nm/Au250nm which allows for a bakeable time of roughly 86 days without compromising the trap voltage performance. This increase in the bakable lifetime of ion traps will remove the need to discard otherwise functional ion traps when vacuum hardware is upgraded, which will greatly benefit ion trap experiments.Comment: 9 Pages, 10 figure

Physical working conditions and subsequent sickness absence : a record linkage follow-up study among 19-39-year-old municipal employees

Purpose Physical work exposures are associated with sickness absence among older employees. We aimed to examine if they similarly contribute to all-cause sickness absence during early and mid-careers. Methods We used questionnaire data on physical work exposures linked to register data on sickness absence from 3542 municipal employees aged 19-39 years. Follow-up for the number of sickness absence days was 12 months. Exposures to physical workload, occupational environmental hazards, and sedentary work were divided into quartiles. In addition, duration of daily exposure to heavy work was included. Negative binomial regression models were used. Results Higher exposure to physical workload or hazardous exposures was associated with a higher number of sickness absence days. The age and gender adjusted rate ratios for sickness absence days among the participants whose exposure to physical workload was in the highest exposure quartile were 2.1 (95% CI 1.8-2.5) compared with those whose exposure was in the lowest quartile. In addition, rate ratios for sickness absence days among participants who reported that they do heavy physical work 1.1-2.0 h, 2.1-4.0 h or over 4 h daily were 1.6 (1.3-1.9), 1.5 (1.3-1.8) and 1.7 (1.5-2.1), respectively, compared with those who reported not doing physical work. Further adjustment for lifestyle factors or health characteristics attenuated the associations only slightly. Conclusion Exposure to physically demanding work is associated with a higher number of sickness absence days among municipal employees below 40 years of age. Physical working conditions should be considered when aiming to support later work ability.Peer reviewe

The Effects of a Prescribed Burn on Small Mammals in an Ohio Tallgrass Prairie

Prescribed burning is used on prairies for increased prairie health and to manage the communities of organisms that rely on the prairie’s natural resources. Small mammals are also affected by the burning of prairies. Previous research by Chance in 1986 and Cook in 1950 has established that burning decreases the small mammal capture rates in the burned area because of the habitat loss and rapid change of habitat post-burn that stresses the animals and leads to lower reproductive levels (Chance, 1986). Other studies by Francl and Small also showed that small mammal populations did not return to pre-burn numbers even after 16 months of evaluation (Francl, K. E., & Small, C. J., 2013). We hypothesize that small mammal populations will decrease in the prairie after burning because of a lack of habitat and food source and that they will emigrate from the burning site to nearby prairie or similar habitat. We will use baited Sherman live traps placed at 25 meter intervals in order to estimate the various small mammal populations in each of the observed habitats. We will plot the capture locations on a map of the area in order to track how stress affects the shift of population density

Leadership Training for Oral Health Professionals: A Call to Action

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153632/1/jddj002203372012762tb05245x.pd

Dry Screw Compressors In Process Gas Applications Including Maintenance Considerations.

LecturePg. 3-20The dry screw compressor, which combines the advantages of positive displacement with rotary motion, is gaining wider international acceptance for process gas applications. The selection of dry screw compressors is dependent upon proper evaluation of the thermodynamic and mechanical characteristics inherent with this type of compressor. To be discussed are the selection parameters, capabilities, and limitations that must be considered for any process gas compressor application. The selection parameters include, but are not limited to, the following: • Application range: Flows, pressures and temperatures suited for screw compressors as compared to other types of compressors. • Gas handled: Molecular weight variations, corrosive elements, erosive components, entrained liquids, polymer formation, and other gas characteristics that can best be handled by dry screw compressors. • Process control of flows, pressures and temperatures. • Compliance with recognized design standards, i.e., API, PNEUROP. • Construction features and design parameters that make dry screw compressors suitable for a wide range of applications. This section discusses bearing loading, shaft bending stresses, torsional and lateral vibration analysis, and other mechanical design criteria. The maintenance section of this presentation is intended to offer a broad overview of this equipment and its unique characteristics and special requirements. Particular emphasis will be placed on the restoration of aero performance, which may over extended periods of time deteriorate due to rotor and casing clearance degradation. Topics include predictive and preventative maintenance practices and guidelines, which can extend the useful life of the equipment and minimize unexpected outages, field overhaul techniques, repair shop procedures and rotor and case repairs including welding, coatings, seal stripping, and metal locking

Analysis of a Putative Promoter in Mycobacteriophage JacoRen57

JacoRen57 is a cluster AB mycobacteriophage that infects Mycobacterium smegmatis mc²155. We recently reported on the characterization of a putative promoter in JacoRen57 using an mCherry reporter construct. This promoter is present in a gap upstream of a gene that is present in all AB phages. In all cases, these are forward genes immediately following a long series of reverse genes. The genes are most frequently identified as a RecA-like DNA recombinases but also as RepA by bioinformatics. To further analyze this putative promoter and gene product, NWC Molecular Genetics students cloned the RecA-like DNA recombinase into an E. coli expression vector with a TVMV removable N-terminal His-tag. They expressed and we purified the tagged protein and are using it to immunize Balb/c mice. We plan to use the antiserum to confirm RecA-like DNA recombinase expression patterns when JacoRen57 infects M. smegmatis

Real-world outcomes of sipuleucel-T treatment in PROCEED, a prospective registry of men with metastatic castration-resistant prostate cancer.

BackgroundThe large registry, PROVENGE Registry for the Observation, Collection, and Evaluation of Experience Data (PROCEED)(NCT01306890), evaluated sipuleucel-T immunotherapy for asymptomatic/minimally symptomatic metastatic castration-resistant prostate cancer (mCRPC).MethodsPROCEED enrolled patients with mCRPC receiving 3 biweekly sipuleucel-T infusions. Assessments included overall survival (OS), serious adverse events (SAEs), cerebrovascular events (CVEs), and anticancer interventions (ACIs). Follow-up was for ≥3 years or until death or study withdrawal.ResultsIn 2011-2017, 1976 patients were followed for 46.6 months (median). The median age was 72 years, and the baseline median prostate-specific antigen level was 15.0 ng/mL; 86.7% were white, and 11.6% were African American. Among the patients, 1902 had 1 or more sipuleucel-T infusions. The median OS was 30.7 months (95% confidence interval [CI], 28.6-32.2 months). Known prognostic factors were independently associated with OS in a multivariable analysis. Among the 1255 patients who died, 964 (76.8%) died of prostate cancer (PC) progression. The median time from the first infusion to PC death was 42.7 months (95% CI, 39.4-46.2 months). The incidence of sipuleucel-T-related SAEs was 3.9%. The incidence of CVEs was 2.8%, and the rate per 100 person-years was 1.2 (95% CI, 0.9-1.6). The CVE incidence among 11,972 patients with mCRPC from the Surveillance, Epidemiology, and End Results-Medicare database was 2.8%; the rate per 100 person-years was 1.5 (95% CI, 1.4-1.7). One or more ACIs (abiraterone, enzalutamide, docetaxel, cabazitaxel, or radium 223) were received by 77.1% of the patients after sipuleucel-T; 32.5% and 17.4% of the patients experienced 1- and 2-year treatment-free intervals, respectively.ConclusionsPROCEED provides contemporary survival data for sipuleucel-T-treated men in a real-world setting of new life-prolonging agents, which will be useful in discussing treatment options with patients and in powering future trials with sipuleucel-T. The safety and tolerability of sipuleucel-T in PROCEED were consistent with previous findings