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Summary: Precisely measuring the number and somatic volume of neurons in the central nervous system at single-cell resolution is technically challenging. Here, we combine multiple techniques to address this challenge in optically cleared mouse spinal cords. We describe in vivo neuron labeling approaches, tissue-clearing technology, light sheet fluorescence microscopy, and machine learning-guided imaging analysis. This combination provides a precise determination of the cell number and somatic volume of any neuron population in the spinal cords. : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

In this conceptual article, we argue for the need to examine power relations in continuous improvement (CI) in education. Specifically, we contend that examining power in CI requires an examination of practices that constitute the work of CI. Drawing on practice theory, we conceptualize practice and power and use these constructs to examine a CI effort on improving mathematical proficiency in an elementary school. From this case, we draw out three power moves to illustrate how examining power through practice in CI can generate insight into the varied power dynamics in a CI effort. We end by arguing for more examinations into the practice of CI work to understand power relations and the enactment of CI efforts in education broadly. [ABSTRACT FROM AUTHOR]

Objectives: This study described the clinical profile of patients with keratoconus at a single tertiary referral hospital. Methods: This was a single-center, retrospective, cross-sectional study that reviewed medical records of patients diagnosed with keratoconus from January 2015 to August 2022. Data on the clinical profile, intervention, and clinical outcomes were collected from the chart review. Results: Forty (40) patients (79 eyes) were included in the study. Majority (98%) had bilateral disease in which 22 (55.5%) were affected asymmetrically. The mean age was 21 years. Most patients (72.5%) were male. Blurring of vision was the chief complaint in all patients. Atopy was present in 23 patients (57.5%). History of vigorous eye rubbing was present in 31 (77.5%). The mean interval from onset of symptoms to consult was 46.4 ± 33.38 months. The mean pinhole corrected distance visual acuity was 0.47 ± 0.41 (Snellen equivalent of 20/59). The average spherical equivalent was -7.48D ± 6.99D. Corneal protrusion on slit-lamp biomicroscopy was seen in 78 eyes (98.7%). Other findings included Fleischer ring (53.2%), Vogt's striae (19.0%), and apical corneal scar (24.0%). Only one eye (1.3%) had no corneal findings. Thirty-nine eyes (49.3%) were classified as advancedsevere keratoconus. Rigid contact lens was planned for 60 eyes (75.9%). Sixty-two eyes (78.5%) were for collagen cross-linking. Deep anterior lamellar keratoplasty was planned in 10 eyes (12.7%) and penetrating keratoplasty in two eyes (2.5%). Conclusion: Keratoconus at the Philippine General Hospital was most frequently seen in young males and asymmetrically affects both eyes. Patients consulted relatively late and presented with a more advanced stage of the disease. History of ocular allergy and eye rubbing were significant risk factors. Improving awareness of this condition must be emphasized to detect keratoconus earlier. [ABSTRACT FROM AUTHOR]

Objective: This paper demonstrated the effectiveness of intrastromal injection of levofloxacin 1.5% ophthalmic solution in the management of recalcitrant Gram-positive bacterial keratitis. Methods: This is a report on two cases of recalcitrant bacterial keratitis encountered at the External Diseases and Cornea Clinic of the Department of Ophthalmology and Visual Sciences at the Philippine General Hospital. Results: Two middle-aged females presented with bacterial keratitis unresponsive to previous antibiotic treatment with impending corneal perforation. The Gram stain of the corneal scraping in the first case revealed Gram-positive cocci, while the second case showed encapsulated Gram-positive bacilli and encapsulated Grampositive cocci in chains. In both cases, repeated intrastromal injections of levofloxacin 1.5% in addition to increasing the frequency of topical levofloxacin 1.5% resulted in marked improvement in visual acuity and resolution of deep stromal infiltrates and hypopyon. Conclusion: These cases highlighted the utility of intrastromal levofloxacin 1.5% ophthalmic solution in the management of recalcitrant Gram-positive bacterial keratitis. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, state legislators rushed to amend their public health emergency statutes or state's constitution to alter the balance of power between the executive and legislative branches during public health emergencies. The power to exercise an unconditional and unilateral legislative veto of a governor's declaration of public health emergency is among one of the most forceful of these pandemic-era amendments. The Pennsylvania legislature attempted to exercise this kind of power in June 2020 to prematurely terminate the governor's declaration of public health emergency, which was challenged in Wolf v. Scarnati. While the Supreme Court of Pennsylvania held that this violated the Pennsylvania Constitution's presentment clause, the Pennsylvania legislature lost the battle, but won the war; Pennsylvania voters approved a constitutional amendment to the state's presentment clause in May 2021, creating an unrestrained exception for legislative vetoes of the governor's declarations of public health emergency. Kentucky, New York, Florida, and New Hampshire's legislatures granted themselves similar statutory legislative vetoes in the wake of the pandemic. These self-grants of unfettered power to override a governor open the door for partisan politics to more easily derail future public health emergency responses. This Note argues that these legislative vetoes are facially unconstitutional and that, if used, will likely face the same fate as the legislative veto at issue in Scarnati. With that fate in mind, should states that want to enhance legislative oversight and executive branch accountability during a public health emergency follow Pennsylvania's example and carve an exception into their constitutions, or work within the current constitutional system to achieve these objectives through other means? This Note endorses the latter approach. Rather than tinker with bedrock constitutional principles of separation of powers and checks and balances as Pennsylvania has, this Note endorses a legislative framework created by the Uniform Law Commission as a constitutional, albeit imperfect, legislative solution to address the need for improved oversight of executive branch declarations and orders and interbranch cooperation in order to best serve the public health needs of its people. [ABSTRACT FROM AUTHOR]

This paper presents a heuristic constructive algorithm (HCA) for optimal capacitor placement on distribution systems. This is a nonlinear mixed integer optimization problem. In the proposed approach, the integer variables are represented using sigmoid function, thus interior point optimal power flow formulation can be applied to obtain sensitivity indexes based on Lagrange multipliers, reactive power, and bus voltage. The methodology is applied to two power distribution systems, and the results are compared with those obtained using a genetic algorithm approach. Index Terms--Heuristic programming, Lagrange multipliers, optimal capacitor placement, optimal power flow.

This work presents a new formulation for the power flow problem, with explicit representation of the neutral conductor and grounding. This methodology has been named the four-conductor current injection method (FCIM). The Newton-Raphson method is applied to solve the set of nonlinear current injection equations that are derived using phase coordinates, and the complex variables are written in rectangular form. The proposed algorithm can be used to analyze both balanced and unbalanced systems, meshed or radial, with controls and distributed generation, and is shown to be very efficient and robust for large scale systems. Index Terms--Current injection method, distributed generation, distribution systems, four-wire systems, induction machine modeling, three-phase power flow, unbalanced operation.

This paper presents a new approach for distribution system reconfiguration (DSR) based on optimum power flow (OPF) in which the branch statuses (open/close) are represented by continuous functions. In the proposed approach, all branches are initially considered closed, and from the OPF results, a heuristic technique is used to determine the next loop to be broken by opening one switch. Then the list of switches that are candidates to be opened is updated, and the above process is repeated until all loops are broken, making the distribution system radial. This paper includes results and comparisons on test systems utilized in three classical papers published in the technical literature, as well as in a previous paper by the authors. Results obtained on a real large-scale distribution system are also presented. Index Terms--Heuristic optimization technique, losses, optimum power flow (OPF), radial distribution networks, reconfiguration.

This paper presents an optimum power flow (OPF) modeling algorithm that uses the primal-dual interior point technique to determine the best investment strategy in the transmission line expansion problem. In the proposed method, the expansion decision (0 or 1) is mitigated by using a sigmoid function, which is incorporated in the OPF problem through the modified dc power flow equations. The investment decision is taken using a new heuristic model based on good sensitivity produced by the OPF results. Additionally, the transmission power losses are considered in the network model. The proposed methodology has been compared with methods available in the literature, using both a test system and an equivalent of the southeastern Brazilian system. Index Terms--Heuristic algorithm, interior point method, sigmoid function, transmission network losses, transmission system expansion.

This paper presents a reconfiguration algorithm that is specially suited to large-scale distribution systems. The algorithm uses a heuristic strategy that starts with the system in a meshed status, with all maneuverable switches closed. The choice of the switches to be opened is based on the calculation of the minimum total system losses, using a load-flow program. A refinement on this procedure, based on branch status exchange, is described. The paper includes results and comparisons on test systems utilized in three classical papers published in the technical literature. Results obtained on a real large-scale distribution system are also presented. Index Terms--Heuristic optimization technique, losses, power system restoration, radial distribution networks, reconfiguration.

As a safety measure for certain applications in Nuclear. Power Stations, cable trays must be wrapped with a fireproof material. In this paper a new implementation of a thermal model is presented, suitable for the determination of the ampacity derating of electric cables in wrapped trays. Model simulation predictions have been compared with field tests to validate the model. Better agreement between simulations and experimental results is obtained when the standard procedure to determine the power loss in the cable mass is modified to account for the actual measured height of the cable mass in the tray. Keywords: Ampacity, Insulated Conductors, Fire Protection, Thermal Influences.

This letter describes a new voltage controlled bus (PV bus) representation in connection with the three-phase current injection method-TCIM of power flow analysis. This representation requires an augmented system of linearized equations to incorporate the reactive power as a dependent variable. Tests and comparisons between the former and the new approach are described and the improved stiffness of this new proposition is demonstrated. Index Terms--Current injection power flow, distribution power flow, PV buses, unbalanced power flow.

Background and Context: Continuous improvement and networked improvement science have emerged as prominent approaches to improving schools. Although continuous improvement approaches have generated promising results in education, how these efforts come to be enacted remains a crucial question that can generate insight into how these approaches can be improved. Purpose and Objective: Our study is focused on understanding how improvement is performed by focusing on the process of generating a shared aim statement in a teacher-preparation improvement network. We seek to understand how practitioners within a network a) engage a central tension (between language acquisition and multilingualism), b) negotiate this tension, and c) reach a settlement that results in a shared aim. Setting: This study takes place in a teacher-preparation improvement network as part of the California Teacher Education Research and Improvement Network (CTERIN). The focus of the network centered on improving the preparation of candidates to build on multilingual students' strengths. Participants: The improvement network that is the focus of our research consists of 49 teacher educators across eight teacher preparation programs as well as three facilitators who were part of CTERIN, including the two authors of this study. Research Design: Our analysis examines the interactions among teacher educators and improvement facilitators to unveil the practices that they engaged in to produce a shared aim. Data for this study include audio and video recordings of three 90-minute videoconference meetings, audio-video of a two-day in-person convening, and improvement artifacts such as fishbone and driver diagrams. Findings: Our study highlights the range of practices that practitioners engaged in and how those evolved as they negotiated and settled a tension between language acquisition and multilingualism. As the process of generating an aim unfolded, teacher educators engaged in the practices of aspirationalizing, dualizing, recentering, rerouting, clarifying, tuning, and converting. Conclusions and Recommendations: We argue that these practices make visible that the process of generating an aim statement is a complex and complicated process that requires negotiation and a recognition that some perspectives are foregrounded and others are backgrounded. Understanding this process has implications for how improvement facilitators engage practitioners in the process of doing improvement and generates theory of improvement implementation by highlighting how disparate teams, individuals, and organizations reaching sharedness requires negotiating, foregrounding, and backgrounding. [ABSTRACT FROM AUTHOR]

This study aims to examine coherence in a teacher preparation program relative to equity. Using performance assessments and artifacts from coursework, we explore how candidates define equity, what equitable practices they enact in their field placements, and whether a relationship exists between their conceptualizations and their practice. We found that candidates' conceptualizations of equity were characterized by five categories; however, their conceptualizations were varied and wide ranging. Findings also show that candidates emphasized attention to student thinking in their teaching, a practice often described in frameworks for ambitious mathematics teaching. Lastly, we found little evidence of consistency between candidates' conceptualizations and their instructional practices. The findings suggest a need to examine the coherence among various features of the teacher education program design and the experiences offered to candidates in these programs. [ABSTRACT FROM AUTHOR]

This paper presents a new sparse formulation for the solution of unbalanced three-phase power systems using the Newton--Raphson method. The three-phase current injection equations are written in rectangular coordinates resulting in an order 6n system of equations. The Jacobian matrix is composed of 6 x 6 block matrices and retains the same structure as the nodal admittance matrix. Practical distribution systems were used to test the method and to compare its robustness with that of the backward/forward sweep method. Index Terms--Unbalanced Power Flow, Current Injection Power Flow, Newton Raphson Power Flow, Distribution Power Flow.