Citizen Science in Postsecondary Education: Current Practices and Knowledge Gaps.

Citizen science involves the public in science to investigate research questions. Although citizen science facilitates learning in informal educational settings, little is known about its use or effects in postsecondary (college or university) settings. Using a literature review and a survey, we describe how and why citizen science is being used in postsecondary courses, as well as the impacts on student learning. We found that citizen science is used predominantly in biologically related fields, at diverse types of institutions, to improve student engagement and expose students to authentic research. Considerable anecdotal evidence supporting improved student learning from these experiences exists, but little empirical evidence exists to warrant any conclusion. Therefore, there is a need to rigorously assess the relationship between citizen science participation and postsecondary student learning. We highlight considerations for instructors planning to incorporate citizen science and for citizen science projects wanting to facilitate postsecondary use.

Farm Vehicle Following Distance Estimation Using Deep Learning and Monocular Camera Images.

This paper presents a comprehensive solution for distance estimation of the following vehicle solely based on visual data from a low-resolution monocular camera. To this end, a pair of vehicles were instrumented with real-time kinematic (RTK) GPS, and the lead vehicle was equipped with custom devices that recorded video of the following vehicle. Forty trials were recorded with a sedan as the following vehicle, and then the procedure was repeated with a pickup truck in the following position. Vehicle detection was then conducted by employing a deep-learning-based framework on the video footage. Finally, the outputs of the detection were used for following distance estimation. In this study, three main methods for distance estimation were considered and compared: linear regression model, pinhole model, and artificial neural network (ANN). RTK GPS was used as the ground truth for distance estimation. The output of this study can contribute to the methodological base for further understanding of driver following behavior with a long-term goal of reducing rear-end collisions.

Randomized trial of cesarean vs vaginal delivery for effects on the pelvic floor in squirrel monkeys.

BACKGROUND: Vaginal delivery is a risk factor in pelvic floor disorders. We previously described changes in the pelvic floor associated with pregnancy and parturition in the squirrel monkey, a species with a humanlike pattern of spontaneous age- and parity-associated pelvic organ prolapse. OBJECTIVE: The potential to prevent or diminish these changes with scheduled cesarean delivery (CD) has not been evaluated. In a randomized, controlled trial, we compared female squirrel monkeys undergoing spontaneous vaginal delivery with those undergoing scheduled primary CD for pelvic floor muscle volumes, muscle contrast changes, and dynamic effects on bladder neck position. STUDY DESIGN: Levator ani, obturator internus, and coccygeus (COC) muscle volumes and contrast uptake were assessed by magnetic resonance imaging in 20 nulliparous females examined prior to pregnancy, a few days after delivery, and 3 months postpartum. The position of bladder neck relative to bony reference line also was assessed with abdominal pressure using dynamic magnetic resonance imaging. RESULTS: Baseline measurements of 10 females randomly assigned to scheduled primary CD were not different from those of 10 females assigned to spontaneous vaginal delivery. Levator ani and obturator internus muscle volumes did not differ between groups, while volumes were reduced (P < .05) in the observation immediately after pregnancy. The COC muscles increased (P < .05) immediately after delivery for females in the spontaneous vaginal delivery group, but not for females in the scheduled CD group. Position of the bladder neck descended (P < .05) by 3 months postpartum in both groups. CONCLUSION: Scheduled CD diminishes changes in COC muscle volume and contrast reported to be associated with spontaneous vaginal delivery in squirrel monkeys. However, pelvic support of the bladder was not protected by this intervention suggesting that effects of pregnancy and delivery are not uniformly prevented by this procedure.

Lack of association between pelvic outlet diameter and pelvic organ prolapse in squirrel monkeys.

INTRODUCTION AND HYPOTHESIS: The aim was to test the hypothesis that the pelvic outlet diameter (POD) is associated with pelvic organ prolapse (POP) in squirrel monkeys. METHODS: Magnetic resonance images (MRI) were obtained from 55 females with and without POP. Commercial software was used by two observers to measure the POD. POD, age, parity, and weight for the two groups were compared using Student's t test. Associations of age, parity, and body weight with POD were evaluated with linear regression analysis. Multiple regression analysis examined the relationships of age, parity, and POD with POP. Receiver operating curve methods were used to set thresholds. RESULTS: Observers concurred on measurements (Cronbach's alpha = 0.96 with lower 95% confidence limit of 0.94). POD was not related to parity (p = 0.10) or weight (p = 0.053), but was inversely related to age (p = 0.011). Animals with POP did not differ from those without POP with regard to age (p = 0.10), weight (p = 0.17), or POD (p = 0.99). The groups differed with regard to parity (p = 0.007) and multiple regression methods demonstrated that only parity had a significant relationship with POP (p = 0.002). Parity greater than 2 had 64% specificity and 89% sensitivity for POP. CONCLUSIONS: POD size does not contribute to POP in squirrel monkeys. This study confirms that among variables of age, body weight, POD, and parity, only parity appears as a risk factor for POP in squirrel monkeys.

Harmful effects of true-to-life nanoplastics derived from PET water bottles in human alveolar macrophages.

The increasing presence of secondary micro/nanoplastics (MNPLs) in the environment requires knowing if they represent a real health concern. To such end, an important point is to test representative MNPLs such as the denominated true-to-life MNPLs, resulting from the degradation of plastic goods in lab conditions. In this study, we have used polyethylene terephthalate (PET) NPLs resulting from the degradation of PET water bottles. Since inhalation is an important exposure route to environmental MNPLS, we have used mouse alveolar macrophages (MH-S) as a target cell, and the study focused only on the cells that have internalized them. This type of approach is novel as it may capture the realistic adverse effects of PETNPLs only in the internalized cells, thereby mitigating any biases while assessing the risk of these MNPLs. Furthermore, the study utilized a set of biomarkers including intracellular reactive oxygen species (ROS) levels, variations on the mitochondrial membrane potential values, and the macrophage polarization to M1 (pro-inflammatory response) and M2 (anti-proinflammatory response) as possible cellular effects due to PETNPLs in only the cells that internalized PETNPLs. After exposures lasting for 3 and 24 h to a range of concentrations (0, 25, 50, and 100 µg/mL) the results indicate that no toxicity was induced despite the 100% internalization observed at the highest concentration. Significant intracellular levels of ROS were observed, mainly at exposures lasting for 24 h, in an indirect concentration-effect relationship. Interestingly, a reduction in the mitochondrial membrane potential was observed, but only at exposures lasting for 24 h, but without a clear concentration-effect relationship. Finally, PETNPL exposure shows a significant polarization from M0 to M1 and M2 subtypes. Polarization to M1 (pro-inflammatory stage) was more marked and occurred at both exposure times. Polarization to M2 (anti-inflammatory stage) was only observed after exposures lasting for 24 h. Due to the relevance of the described biomarkers, our results underscore the need for further research, to better understand the health implications associated with MNPL exposure.

Hazard assessment of nanoplastics is driven by their surface-functionalization. Effects in human-derived primary endothelial cells.

During plastic waste degradation into micro/nanoplastics (MNPLs) their physicochemical characteristics including surface properties (charge, functionalization, biocorona, etc.) can change, potentially affecting their biological effects. This paper focuses on the surface functionalization of MNPLs to determine if it has a direct impact on the toxicokinetic and toxicodynamic interactions in human umbilical vein endothelial cells (HUVECs), at different exposure times. Pristine polystyrene nanoplastics (PS-NPLs), as well as their carboxylated (PS-C-NPLs) and aminated (PS-A-NPLs) forms, all around 50 nm, were used in a wide battery of toxicological assays. These assays encompassed evaluations on cell viability, cell internalization, induction of intracellular reactive oxygen species (iROS), and genotoxicity. The experiments were conducted at a concentration of 100 µg/mL, chosen to ensure a high internalization rate across all treatments while maintaining a sub-toxic concentration. Our results show that all PS-NPLs are internalized by HUVECs, but the internalization dynamic depends on the particle's functionalization. PS-NPLs and PS-C-NPLs internalization modify the morphology of the cell increasing its inner complexity/granularity. Regarding cell toxicity, only PS-A-NPLs reduced cell viability. Intracellular ROS was induced by the three different PS-NPLs but at different time points. Genotoxic damage was induced by the three PS-NPLs at short exposures (2 h), but not for PS-C-NPLs at 24 h. Overall, this study suggests that the toxicological effects of PSNPLs on HUVEC cells are surface-dependent, highlighting the relevance of using human-derived primary cells as a target.

Slits affect the timely migration of neural crest cells via Robo receptor.

BACKGROUND: Neural crest cells emerge by delamination from the dorsal neural tube and give rise to various components of the peripheral nervous system in vertebrate embryos. These cells change from non-motile into highly motile cells migrating to distant areas before further differentiation. Mechanisms controlling delamination and subsequent migration of neural crest cells are not fully understood. Slit2, a chemorepellant for axonal guidance that repels and stimulates motility of trunk neural crest cells away from the gut has recently been suggested to be a tumor suppressor molecule. The goal of this study was to further investigate the role of Slit2 in trunk neural crest cell migration by constitutive expression in neural crest cells. RESULTS: We found that Slit gain-of-function significantly impaired neural crest cell migration while Slit loss-of-function favored migration. In addition, we observed that the distribution of key cytoskeletal markers was disrupted in both gain and loss of function instances. CONCLUSIONS: These findings suggest that Slit molecules might be involved in the processes that allow neural crest cells to begin migrating and transitioning to a mesenchymal type.

Rates and predictors of teen driver crash culpability.

BACKGROUND: Motor-vehicle crash risk is highest among teen drivers. Despite a wealth of research on the topic, there are still many contributors to these crashes that are not well understood. The current study sought to examine the contribution of graduated driver licensing (GDL) restrictions, sex, age, roadway circumstances, and citation history to teen drivers' crash culpability. METHOD: Crash system data from the Iowa Department of Transportation were linked with traffic-related charges from the Iowa Court Information System. Crashes involving teens aged 14 to 17 years between 2016 and 2019 were analyzed (N = 19,847). Culpability was determined using the driver contributing circumstances from the crash report. Moving and non-moving traffic citations issued prior to the date of each crash were considered. A multivariable logistic regression model was constructed to examine predictors of crash culpability. RESULTS: Teen drivers were determined to be culpable for more than two thirds of crashes (N = 13,604, 68.54%). Culpability was more prevalent among males, younger teens, in rural areas, in the presence of reported roadway contributing circumstances, during hours of restricted nighttime driving, and among teens with citation histories that included both moving and non-moving citations. Similarly, multivariable model results indicated that the likelihood of culpability was higher among males, in rural areas, and at each stage of GDL compared to teen drivers with unrestricted licenses. While drivers with a history of both moving and non-moving violations were more likely to be culpable, those with a history of only moving or only non-moving violations were less likely to be culpable compared to those with no violation history. CONCLUSION: Sex, crash location, and GDL stage were associated with teen driver crash culpability. A singular prior moving or non-moving violation may play a protective role in teen crash culpability.

Predictors of rural driver self-reported passing behaviors when interacting with farm equipment on the roadway.

Background: Crashes involving farm equipment (FE) are a major safety concern for farmers as well as all other users of the public road system in both rural and urban areas. These crashes often involve passenger vehicle drivers striking the farm equipment from behind or attempting to pass, but little is known about drivers' perceived norms and self-reported passing behaviors. The objective of this study is to examine factors influencing drivers' farm equipment passing frequencies and their perceptions about the passing behaviors of other drivers. Methods: Data were collected via intercept surveys with adult drivers at local gas stations in two small rural towns in Iowa. The survey asked drivers about their demographic information, frequency of passing farm equipment, and perceptions of other drivers' passing behavior in their community and state when approaching farm equipment (proximal and distal descriptive norms). A multinomial logistic regression model was used to estimate the relationship between descriptive norms and self-reported passing behavior. Results: Survey data from 201 adult drivers showed that only 10% of respondents considered farm equipment crashes to be a top road safety concern. Respondents who perceived others passing farm equipment frequently in their community were more likely to report that they also frequently pass farm equipment. The results also showed interactions between gender and experience operating farm equipment in terms of self-reported passing behavior. Conclusions/Implications: Results from this study suggest local and state-level norms and perceptions of those norms may be important targets for intervention to improve individual driving behaviors around farm equipment.

Titanium-doped PET nanoplastics of environmental origin as a true-to-life model of nanoplastic.

The increased presence of secondary micro/nanoplastics (MNPLs) in the environment requires urgent studies on their potentially hazardous effects on exposed organisms, including humans. In this context, it is essential to obtain representative MNPL samples for such purposes. In our study, we have obtained true-to-life NPLs resulting from the degradation, via sanding, of opaque PET bottles. Since these bottles contain titanium (TiO2NPs), the resulting MNPLs also contain embedded metal. The obtained PET(Ti)NPLs were extensively characterized from a physicochemical point of view, confirming their nanosized range and their hybrid composition. This is the first time these types of NPLs are obtained and characterized. The preliminary hazard studies show their easy internalization in different cell lines, without apparent general toxicity. The demonstration by confocal microscopy that the obtained NPLs contain Ti samples offers this material multiple advantages. Thus, they can be used in in vivo approaches to determine the fate of NPLs after exposure, escaping from the existing difficulties to follow up MNPLs in biological samples.

Understanding undergraduate students' eHealth usage and views of the patient-provider relationship.

eHealth has grown exponentially alongside technology and has become widely accessed by some populations, but little is documented about how undergraduate students use eHealth or perceive their eHealth literacy. As access to online information and non-traditional options for interacting with providers has increased, patient views of the provider-patient relationship may also be changing. This study evaluates how frequently undergraduates use eHealth, how they perceive their ability to use eHealth appropriately, and how they view their patient-provider relationships. A mixed methods approach was used to address the research questions, with quantitative data from a survey and qualitative data from follow-up interviews of twelve of the survey respondents. The survey was distributed to over 650 undergraduate students in introductory biology laboratory courses for students of all fields of interest at one university. Based on 527 survey responses and 12 interviews, students reported commonly using eHealth but being skeptical of telehealth appointments. Although students generally felt capable of finding and interpreting eHealth sources, they were not strongly confident in their ability to do so. Use of eHealth was not seen as altering the patient-provider relationship, but students expressed a desire for their physician to act more as a counselor or advisor than a guardian. Students from minority populations were more likely to use eHealth in comparison to their peers. In addition, student comfort with their provider differed by race and ethnicity, as well as whether they shared the same gender identity as their provider. This research highlights how undergraduate students, who are often making medical decisions for themselves for the first time as adults, access health information and view the patient-provider relationship differently than the traditional guardian or paternalistic model. In addition, having diverse, culturally competent medical providers are critical for students to develop the relationship with their provider that they desire.

Alterations in pelvic floor muscles and pelvic organ support by pregnancy and vaginal delivery in squirrel monkeys.

INTRODUCTION AND HYPOTHESIS: The objective of this study was to measure the effects of pregnancy and parturition on pelvic floor muscles and pelvic organ support. METHODS: Levator ani, obturator internus, and coccygeus (COC) muscle volumes and contrast uptake were assessed by MRI of seven females prior to pregnancy, 3 days, and 4 months postpartum. Bladder neck and cervix position were measured dynamically with abdominal squeezing. RESULTS: The sides of three paired muscles were similar (p > 0.66). COC volumes were greater (p < 0.004) after parturition than before pregnancy or after recovery. COC contrast uptake increased (p < 0.02) immediately after delivery. Bladder neck position both in the relaxed state and abdominal pressure descended (p < 0.04) after delivery and descended further (p < 0.001) after recovery. Cervical position in the relaxed state before delivery was higher (p < 0.001) than postpartum but was unchanged (p = 0.50) with abdominal pressure relative to delivery. CONCLUSION: In squirrel monkeys, coccygeus muscles demonstrate the greatest change related to parturition, and parturition-related bladder neck descent seems permanent.

Emergence and migration of trunk neural crest cells in a snake, the California Kingsnake (Lampropeltis getula californiae).

BACKGROUND: The neural crest is a group of multipotent cells that emerges after an epithelial-to-mesenchymal transition from the dorsal neural tube early during development. These cells then migrate throughout the embryo, giving rise to a wide variety derivatives including the peripheral nervous system, craniofacial skeleton, pigment cells, and endocrine organs. While much is known about neural crest cells in mammals, birds, amphibians and fish, relatively little is known about their development in non-avian reptiles like snakes and lizards. RESULTS: In this study, we show for the first time ever trunk neural crest migration in a snake by labeling it with DiI and immunofluorescence. As in birds and mammals, we find that early migrating trunk neural crest cells use both a ventromedial pathway and an inter-somitic pathway in the snake. However, unlike birds and mammals, we also observed large numbers of late migrating neural crest cells utilizing the inter-somitic pathway in snake. CONCLUSIONS: We found that while trunk neural crest migration in snakes is very similar to that of other amniotes, the inter-somitic pathway is used more extensively by late-migrating trunk neural crest cells in snake.

Using an event-triggered video intervention system to expand the supervised learning of newly licensed adolescent drivers.

OBJECTIVES: We examined whether feedback from an event-triggered video intervention system reduced the number of safety-relevant driving errors made by newly licensed adolescents. METHODS: We used a 1-group pretest-posttest quasi-experimental design to compare the rate of coachable error events per 1000 miles for 18 drivers who were aged 16 years. The intervention consisted of immediate visual feedback provided to the drivers and weekly event reports and videos provided to the drivers and their parents. RESULTS: The number of coachable events was reduced by 61% overall during the intervention (chi(2) = 11.42; P = .001) and did not significantly increase during the second baseline, which was assessed after the intervention ended (chi(2) = 1.49; P = .223). The greatest reduction was seen in the category of improper turns or curves and for drivers identified at the first baseline as "high-event" drivers. CONCLUSIONS: Our results show that immediate visual feedback for adolescents and cumulative video feedback for parents and adolescents during the early period of independent driving can have a dramatic influence on the rate of safety-relevant driving events. To the extent that such events are a proxy for crash risk, we suggest that feedback can enhance adolescent driving safety.

A randomized trial to test the impact of parent communication on improving in-vehicle feedback systems.

This randomized controlled trial evaluated the impact of integrating Steering Teens Safe, a parent communication intervention, with feedback from an in-vehicle video recording system. In-vehicle video systems that trigger a recording when the vehicle exceeds a g-force threshold have been used to provide feedback to young drivers. Few of these programs have involved parental engagement. Parent-teen dyads were randomized to three groups and 150 dyads completed the study. All groups received an in-vehicle video system that recorded driving events. The control group received no feedback or intervention. In the first intervention group, teens received real-time feedback, and parent-teen dyads received summary feedback, based on information recorded by the in-vehicle system. The second intervention group received the same feedback, plus parents were taught strategies to improve communication with their teen about safe driving. The primary outcome variable was unsafe driving event rates per 1000 miles driven and the primary independent variable was group assignment. Generalized linear models were used to calculate effect estimates. Compared with the control group, the Event Recorder Feedback group had a rate ratio of 0.35 (95% CI = 0.24 - 0.50) and the combined intervention group (Event Recorder Feedback and parent communication) had a rate ratio of 0.21 (95% CI = 0.15 - 0.30). Furthermore, the combined intervention group had a significantly lower event rate than the Event Recorder Feedback only group (rate ratio = 0.60, 95% CI = 0.41 - 0.87). While in-vehicle feedback systems can help reduce unsafe driving events in early independent driving, teaching parents strategies for effective communication with their young driver may further improve impact.

Screen for Slit/Robo signaling in trunk neural cells reveals new players.

Slits ligands and their Robo receptors are involved in quite disparate cell signaling pathways that include axon guidance, cell proliferation, cell motility and angiogenesis. Neural crest cells emerge by delamination from neural cells in the dorsal neural tube, and give rise to various components of the peripheral nervous system in vertebrates. It is well established that these cells change from a non-migratory to a highly migratory state allowing them to reach distant regions before they differentiate. However, but the mechanism controlling this delamination and subsequent migration are still not fully understood. The repulsive Slit ligand family members, have been classified also as true tumor suppressor molecules. The present study explored in further detail what possible Slit/Robo signals are at play in the trunk neural cells and neural crest cells by carrying out a microarray after Slit2 gain of function in trunk neural tubes. We found that in addition to molecules known to be downstream of Slit/Robo signaling, there were a large set of molecules known to be important in maintaining cells in non-motile, epithelia phenotype. Furthermore, we found new molecules previously not associated with Slit/Robo signaling: cell proliferation markers, Ankyrins and RAB intracellular transporters. Our findings suggest that neural crest cells use and array of different Slit/Robo pathways during their transformation from non-motile to highly motile cells.

Intraabdominal pressure in women during CrossFit exercises and the effect of age and parity.

To determine intraabdominal pressure (IAP) in women during CrossFit and to determine whether parity, age, or CrossFit experience affects IAP during CrossFit exercises, we evaluated 10 women: 5 experienced and active CrossFitters and 5 who were not regularly engaged in CrossFit. A Laborie urodynamics abdominal pressure probe with the Goby wireless system measured IAP during 10 repetitions of 13 different CrossFit exercises. Women had a mean age of 36 years. A significant difference was found between mean peak IAP of the 5 parous vs the 5 nulliparous women (P = 0.009). Experience with CrossFit did not affect mean peak IAP achieved with exercise. In some exercises, there was a significant change in IAP as participants progressed through repetitions (P = 0.003 for back squats and 0.04 for sit-ups). Participants achieved IAP values that were markedly higher than those previously published.

Exploring the links between groundwater quality and bacterial communities near oil and gas extraction activities.

Bacterial communities in groundwater are very important as they maintain a balanced biogeochemical environment. When subjected to stressful environments, for example, due to anthropogenic contamination, bacterial communities and their dynamics change. Studying the responses of the groundwater microbiome in the face of environmental changes can add to our growing knowledge of microbial ecology, which can be utilized for the development of novel bioremediation strategies. High-throughput and simpler techniques that allow the real-time study of different microbiomes and their dynamics are necessary, especially when examining larger data sets. Matrix-assisted laser desorption-ionization (MALDI) time-of-flight mass spectrometry (TOF-MS) is a workhorse for the high-throughput identification of bacteria. In this work, groundwater samples were collected from a rural area in southern Texas, where agricultural activities and unconventional oil and gas development are the most prevalent anthropogenic activities. Bacterial communities were assessed using MALDI-TOF MS, with bacterial diversity and abundance being analyzed with the contexts of numerous organic and inorganic groundwater constituents. Mainly denitrifying and heterotrophic bacteria from the Phylum Proteobacteria were isolated. These microorganisms are able to either transform nitrate into gaseous forms of nitrogen or degrade organic compounds such as hydrocarbons. Overall, the bacterial communities varied significantly with respect to the compositional differences that were observed from the collected groundwater samples. Collectively, these data provide a baseline measurement of bacterial diversity in groundwater located near anthropogenic surface and subsurface activities.

Utilization of cryopreserved sperm cells based on the indication for storage.

Purpose: Cryopreservation of sperm from human semen has been available since the 1950s. The actual utilization of available cryopreservation technology has been infrequently reported. We set out to examine the utilization and outcomes of cryopreserved sperm cells based on the indication for storage. Materials and Methods: A dataset was developed from retrospective review. The purposes for cryopreservation, eventual utilization, and outcomes of use for insemination were recorded. The types of utilization were accumulated as proportions for different purposes. The timing for use of samples for insemination procedures was evaluated using survival statistics. The frequency of patients arranging to destroy samples was also reported. Results: From September 1988 through March 2015, 1442 samples were cryopreserved. Samples were cryopreserved for four primary purposes: infertility treatments focused on intrauterine insemination (IUI) or in vitro fertilization/intracellular injection (IVF/ICSI), for fertility preservation related to cancer treatment, or prior to military deployment. Total utilization rates were 19.3%. Samples cryopreserved for IUI were more likely to be used (64.3%), while samples cryopreserved as backup for IVF/ICSI were more likely to be destroyed (29.8%). Pregnancy rates varied based on the indication and ART used. Pregnancies per cycle were 35% for IVF/ICSI and were 10% for IUI. Conclusions: Cryopreservation of sperm is a valuable and underutilized resource, particularly amongst male cancer patients. This technology can facilitate infertility treatments based on a variety of indications, including deployment-a patient cohort unique to our dataset.

Time trends for bacterial species and resistance patterns in semen in patients undergoing evaluation for male infertility.

Semen from asymptomatic men who are being evaluated as male partners in interfile couples have been reported to contain a variety of bacteria. Longitudinal studies of the variation of these bacteria over time and their resistance patterns have not been commonly reported. At our institution, residues from semen samples are routinely evaluated for bacteria, including antibiotic sensitivity profiles. We set out to profile the changes in semen bacteria and antibiotic resistance at our institution over time. A total of 72 semen isolates were examined for type of bacteria and sensitivity to a panel of antibiotics. The results were divided into two separate 5-year intervals (the first beginning in 2006, the second in 2011) and compared. The majority of bacteria were skin flora, with Streptococcus and Staphylococcus being the most prevalent. The resistance data for these two pathogens showed minimal statistically significant difference between the two time periods, although the Staphylococcus species did show a trend toward increasing resistance, suggesting that antibiotics currently used in sperm cell preparations may need to be varied.