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While a strong literature base exists around undergraduate experiences in Science, Technology, Engineering, and Math (STEM), few studies examine how students approach the question of "what's next" after graduation. This study examines the impact of social ties on STEM college seniors' plans to enter the STEM workforce, and how race/ethnicity and gender impact postgraduation planning in STEM. We interviewed a racially diverse sample of 39 STEM college seniors at a predominantly White research institution. Analysis showed that students relied on weak and strong social ties in obtaining job leads and valued diversity in the workplace. Some students of color and women experienced negative social ties (via racism and sexism) during internship experiences, which shaped their thinking around postgraduate opportunities. We discuss implications for equity, as well as recommendations for research and practice.

PurposeUreteral access sheaths (UAS) pose the risk of severe ureteral injury. Our prior studies revealed forces ≤6 Newtons (N) prevent ureteral injury. Accordingly, we sought to define the force urologists and residents-in-training typically use when placing a UAS.Materials & methodsAmong urologists and urology residents attending two annual urological conferences in 2022, 121 individuals were recruited for the study. Participants inserted 12Fr, 14Fr, and 16Fr ureteral access sheaths into a male genitourinary model containing a concealed force sensor; they also provided demographic information. Analysis was completed using t-tests and Chi-square tests to identify group differences when passing a 16Fr sheath UAS. Participant traits associated with surpassing or remaining below a minimal force threshold were also explored via polychotomous logistic regression.ResultsParticipant force distributions were: ≤4N (29%), >6N (45%), and >8N (32%). More years of practice were significantly associated with exerting >6N relative to forces between 4-6N; results for >8N relative to 4N-8N were similar. Compared to high-volume ureteroscopists (those performing >20 ureteroscopies/month), physicians performing ≤20 ureteroscopies/month were significantly less likely to exert forces ≤4N (p=0.017 and p=0.041). Of those surpassing 6N and 8N, 15% and 18% respectively were high-volume ureteroscopists.ConclusionsDespite years of practice or volume of monthly ureteroscopic cases performed, most urologists failed to pass 16Fr access sheaths within the ideal range of 4N-6N (74% of participants) or within a predefined safe range of 4N-8N (61% of participants).

Aim To determine stresses generated in the posterior teeth region by two different self-ligating systems, 3M Unitek SmartClip and Damon Q Self-ligating brackets, using the finite element method (FEM). Methodology Computed tomography (CT) scan of maxilla was taken using Mimics software, and the Dicom data were imported into Hypermesh 13.0 software to convert it into a geometric model and then into FEM. Physical models of both the brackets were constructed and positioned on the teeth. Post archwire modeling, contact is defined between the bracket slot and 0.014” NiTi arch wire. The final assembled model was exported to ANSYS 12.1 for analysis, and 60 grams of load was applied at the ends of the arch wire. Results On using 0.014” CuNiTi in both the bracket systems, stresses generated on the root surface were found to be maximum on the first molar region, followed by the first premolar, second molar, canine, and second premolar regions. Comparison between the two bracket systems showed differences in the stresses generated, where higher stresses were generated at all regions in the Damon Q bracket system, except the inter-second premolar region. Conclusion Maximum stresses were observed with the 3M Unitek SmartClip bracket system at the second premolar cervical region when compared to the Damon Q system. In both the cortical bone and cancellous bone, maximum stresses were observed at the second premolar cervical in the Damon Q bracket system region.

Sour cherry (Prunus cerasus L.) is an agriculturally valuable tree that produces fruits used in a range of culinary dishes, beverages, and other products. The progenitor species and number of origins of sour cherry remain unresolved. Here, we performed phylogenetic analyses of plastid genomes and nuclear genes from nine wild species and three historically important sour cherry cultivars. Our analyses identified Prunus fruticosa and Prunus avium as the closest extant relatives of the progenitor species of tetraploid sour cherry. Furthermore, our analyses revealed P. fruticosa as the likely maternal contributor. These findings and transcriptomic datasets should serve as valuable new resources to guide future breeding efforts in sour cherry.

BLDC motors are extensively used in various industries, including CNC machine tools, industrial robots, and electric vehicles. Because of their compact size, high efficiency, high torque-to-power ratios, and low maintenance requirements due to their brushless operation, BLDC motors are the backbone of many industrial automation systems. However, they pose significant challenges when it comes to speed control. In this study, the speed of BLDC motors is controlled by PI-based speed controllers. In the described method, the BLDC motor is commutated using Hall Effect sensors. A proposed approach uses PI to regulate the speed of BLDC motors in an open-loop PWM method. The speed-controlled BLDC motor is analysed using MATLAB/simulink. The hardware of the proposed system is also implemented.

We examined key influences on STEM college seniors' postgraduate plans. Using data from the National Longitudinal Study of Freshmen we utilized multilevel modeling to identify variables associated with planning to pursue a STEM-related job or STEM graduate study after graduation. Key findings emphasize the importance of volunteering and extracurricular activities for women, as well as lower-income and underrepresented racially minoritized students, as well as the relevance of interaction with faculty. Findings also suggest that a certain amount of "opportunity hoarding" exists among majority-status students. We conclude with implications for creating more welcoming, inclusive, and diverse STEM environments.

Abstract The metal‐organic framework (MOF) derived Ni–Co–C–N composite alloys (NiCCZ) were “embedded” inside the carbon cloth (CC) strands as opposed to the popular idea of growing them upward to realize ultrastable energy storage and conversion application. The NiCCZ was then oxygen functionalized, facilitating the next step of stoichiometric sulfur anion diffusion during hydrothermal sulfurization, generating a flower‐like metal hydroxysulfide structure (NiCCZOS) with strong partial implantation inside CC. Thus obtained NiCCZOS shows an excellent capacity when tested as a supercapacitor electrode in a three‐electrode configuration. Moreover, when paired with the biomass‐derived nitrogen‐rich activated carbon, the asymmetric supercapacitor device shows almost 100% capacity retention even after 45,000 charge–discharge cycles with remarkable energy density (59.4 Wh kg–1/263.8 µWh cm–2) owing to a uniquely designed cathode. Furthermore, the same electrode performed as an excellent bifunctional water‐splitting electrocatalyst with an overpotential of 271 mV for oxygen evolution reaction (OER) and 168.4 mV for hydrogen evolution reaction (HER) at 10 mA cm−2 current density along with 30 h of unhinged chronopotentiometric stability performance for both HER and OER. Hence, a unique metal chalcogenide composite electrode/substrate configuration has been proposed as a highly stable electrode material for flexible energy storage and conversion applications.

Background: Renal collecting system injuries are a rare occurrence during percutaneous nephrolithotomy (PCNL). However, when they do happen, the potential for complications rises exponentially the longer the injury goes undetected. This case highlights a possible higher rate of injury when using continuous flow sheaths. Case Presentation: A 65-year-old woman with history of large volume obstructing left-sided renal pelvis stone had an emergent ureteral stent placed for infection and was referred for interval management. Patient was taken for PCNL in the prone split-leg position where a continuous flow ureteral access sheath and a continuous flow nephrostomy sheath was used. Puncture and dilatation were performed under endoscopic guidance to avoid collecting system injury during access. The anesthesiologist discovered abnormalities in the patient's pulmonary ventilation settings. This allowed the surgical team to quickly halt the procedure and place the patient supine where a distended abdomen was discovered consistent with irrigation fluid extravasation into the abdominal cavity. Given concern for abdominal compartment syndrome, interventional radiology was then called to assist in placing a drain in the right lower quadrant of the patient to evacuate the irrigation fluid. This is the second such occurrence in a span of 6 months when using continuous flow ureteral access and nephrostomy sheaths. Conclusion: Renal collecting systems injuries are infrequent when access is obtained under endoscopic guidance. Prompt recognition of physiologic breathing abnormalities allowed the surgical team to quickly treat the injury, preventing further complications from arising in the setting of a diagnosis where time to detection plays an important role in prognosis. However, given that this is the second such injury, the usage of continuous flow sheaths and their rate of associated complications and injuries must be thoroughly examined.

Introduction: Encrustation of implanted urinary tract devices is associated with significant morbidity. Pellethane® is a polyether-based compound noted for its strength, porosity, and resistance to solvents. We assessed Pellethane thermoplastic polyurethane (TPU) with and without surface coatings 2-hydroxyethyl methacrylate (HEMA) and tetraethylene glycol dimethyl ether (TETRA) for the potential to resist encrustation in an artificial urine environment. Materials and Methods: Samples of Pellethane TPU, HEMA Pellethane TPU, TETRA Pellethane TPU, and hydrogel-coated ureteral stent (Cook®) were suspended in a batch-flow model with an artificial urine solution (AUS). Every 48 hours for 90 days, 40% of the solution was replaced with fresh AUS. All samples were stored in a 37°C incubator. Subsequently, the samples were thoroughly dried for 48 hours before weighing. Scanning electron microscopy was used to assess the degree of encrustation. Nu-Attom Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used to determine the precise compositions of the encrustation specifically with regard to calcium, magnesium, and phosphate. Results: At the conclusion of the 90-day trial, the samples were analyzed, and the average mass changes were as follows: stent 63.78%, uncoated Pellethane TPU 11.50%, HEMA-coated Pellethane TPU 2.90%, and TETRA-coated Pellethane TPU 0.60%. Pellethane TPU products, and specifically those coated with HEMA and TETRA, exhibited less average mass increase and a lesser propensity to form encrustation than the traditional urinary tract stent. The mass increases noted on coated Pellethane devices were primarily ionic, whereas that of the stent was not. Conclusion: Pellethane, particularly with an HEMA-based preventative coating, may serve as a favorable alternative to traditional urinary stent material, providing its improved resistance to encrustation.

BACKGROUND: The volumetric relationship between the tongue and the oral cavity is an important factor in tooth alignment and occlusion. The aim of this study was to evaluate the difference in tongue and airway volume in skeletal Class I and Class II malocclusion. MATERIALS AND METHODS: The CBCT data which comprised of 30 skeletal Class I and 30 skeletal Class II was stored in DICOM format. Tongue volume and airway volume was analyzed with the help of 3D dolphin software. Values obtained were subjected to statistical analysis with help of SPSS. RESULTS: Skeletal Class I pattern had more tongue volume with a mean of 45.32 mm3 than skeletal Class II pattern with mean value of 40.27mm3 with P value of