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Osteocytes are bone cells that can sense mechanical cues (stress and strain) and respond by releasing biochemical signals that direct bone remodeling. This process is called mechanotransduction which, in osteocytes, is not well understood yet because in vivo studies have proven difficult due to the complexity and inaccessibility of the flow–osteocyte lacuna-canaliculi system. While in silico studies (modeling and simulation) have become powerful, currently computational studies for the system often omit the fluid–structure interaction (FSI) between the cell and the surrounding fluids. To investigate the role of FSI in osteocyte mechanotransduction, we introduce a two-dimensional coarse-grained yet integrative model for flow–osteocyte interaction in a lacuno-canalicular network. The model uses the lattice Boltzmann immersed boundary framework to incorporate the flexible osteocyte (membrane, cytoskeleton, and cytosol), its processes, the interstitial fluid, and the rigid extracellular matrix that encases the system. One major result of our model is that the stress and strain tend to attain their local maxima near the regions where the processes meet the membrane of the main body. [ABSTRACT FROM AUTHOR]

The Full Law Analysis Scattering System Hub (FLASSH) is a modern, advanced code that evaluates the thermal scattering law (TSL) along with accompanying cross sections. FLASSH features generalized methods that accommodate any material structure. Historical approximations including incoherent and cubic approximations have been removed. Instead, the latest release of FLASSH features advanced physics options including distinct effect corrections (one-phonon contributions) and noncubic formulations. Noncubic elastic and inelastic contributions are necessary to accurately evaluate one-phonon contributions. Both noncubic and one-phonon calculations require high-density sampling of the various scattering directions. Optimization and parallelization of these routines were therefore necessary to produce results in a reasonable computational time frame. With these notable improvements to the generalized TSL, FLASSH 1.0 can meet benchmark requirements by permitting realistic comparisons with experiments for both TSLs and the resulting integrated cross sections. Within FLASSH, these high-fidelity TSLs can be applied also to the resonance region to evaluate accurate, material structure-dependent Doppler broadening that captures the observed experimental behavior. Additional features including a graphical user interface (GUI), plotting diagnostics, and formatted output options including ACE files allow users to complete a TSL evaluation with minimal input and maximum flexibility. The user GUI creates input files for FLASSH, reducing user error and also providing built-in error checks. Autofill options and suggested input values help make TSL evaluation accessible to novice users. The FLASSH code is compiled to run on both Windows and Linux platforms with automatic parallelization. [ABSTRACT FROM AUTHOR]

Detecting neurotoxic heavy metals, such as Cd2+, is crucial as the widespread metal containination poses significant global health concerns, These neurotoxic agents can breach the blood-brain barrier, causing severe and often irreversible damage to the central nervous system and other vital organs. A highly sensitive and rapid detection method for these metals is an essential next step in sensor technology to mitigate these detrimental health effects and start early therapeutics. Conventional techniques for detecting metals have their own limitations, resulting in altering the speciation of metals, a factor that determines their toxicity. In this study, we fabricate a novel Cd2+ sensor by modifying the surface of carbon fiber microelectrodes by electrodeposition of gold nanoparticles. Our sensor employs fast-scan cyclic voltammetry with a 100 ms temporal resolution, marking it the fastest Cd2+ detection sensor. We established a calibration based on the concentration of Cd2+ in a tris buffer that mimics artificial cerebellum fluid, yielding an impressive limit of detection of 1.32 nM. Selectivity tests and con-tplexation studies with different metal ions and ligands reveal that our sensor can detect free Cd2+ in complex matrices. We also analyzed the solution chemistry of Cd2+ in different matrices using PHREEQC, a commonly used geochemical model, and found our electrochemical data well agreed with PHREEQC findings, thus validating our sensor's response. Additionally, our sensors performed optimally with excellent stability and sensitivity when detecting Cd,2+ in artificial urine, showcasing an excellent potential for our sensors to be used for future biological samples and in vivo measurements. [ABSTRACT FROM AUTHOR]

Arrhythmogenic cardiomyopathy (ACM) is an inherited disorder characterized by fibro-fatty infiltration with an increased propensity for ventricular arrhythmias and sudden death. Genetic variants in desmosomal genes are associated with ACM. Incomplete penetrance is a common feature in ACM families, complicating the understanding of how external stressors contribute towards disease development. To analyze the dual role of genetics and external stressors on ACM progression, we developed one of the first mouse models of ACM that recapitulates a human variant by introducing the murine equivalent of the human R451G variant into endogenous desmoplakin (DspR451G/+). Mice homozygous for this variant displayed embryonic lethality. While DspR451G/+ mice were viable with reduced expression of DSP, no presentable arrhythmogenic or structural phenotypes were identified at baseline. However, increased afterload resulted in reduced cardiac performance, increased chamber dilation, and accelerated progression to heart failure. In addition, following catecholaminergic challenge, DspR451G/+ mice displayed frequent and prolonged arrhythmic events. Finally, aberrant localization of connexin-43 was noted in the DspR451G/+ mice at baseline, becoming more apparent following cardiac stress via pressure overload. In summary, cardiovascular stress is a key trigger for unmasking both electrical and structural phenotypes in one of the first humanized ACM mouse models. [ABSTRACT FROM AUTHOR]

Neurodegenerative diseases (NDD) pose a global health concern despite the numerous therapeutics aimed at slowing their multifactorial progression. Carbon-fiber microelectrodes (CFMs) have provided important electrochemical insights into NDDs, yet their single neurotransmitter analysis limits real-time understanding of interactions. Addressing this. a multi-bore microelectrode with multiple carbon fibers (CF) offers insights into evoked neurotransmitter heterogeneity and interactions at specific locations. However, challenges in engineering such microelectrodes stem from lengthy processing times and costs. This study presents a double-bore CFM with two sensing components, each bore housing a single CF as a unique electrode for specific analyte detection. Characterizing the sensor with dopamine, serotonin, ascorbic acid, and Cu(II) using fast-scan cyclic voltammetry (FSCV), simultaneous signals were acquired in analyte mixtures. Calibration curves revealed non-interference at nm-wide separation during ultra-fast scan rates. Exciting interactions between ascorbic acid and Cu(II) were observed. Additionally. we successfully performed co-detection of various toxic heavy metal ions, an exciting find for inetal detection. This study reports the first use of double-bore CFM for simultaneous detection of two analytes without altering electrochemical parameters at a 100 ms resolution. This highlights its excellent potential for in vivo real-time detection of multiple neurotransmitters and toxic metal ions. [ABSTRACT FROM AUTHOR]

Increased arsenic contamination is a global concern due to the detrimental health hazards associated with arsenic poisoning. Arsenite interferes with cellular respiration, causing cell injury and death: thus, long-term exposure causes cancer, skin lesions, cardiovascular diseases, diabetes, and death. Therefore. developing a selective, robust, cost-effective arsenite sensor is crucial. Traditionally employed methods of arsenite detection require sophisticated equipment, expert personnel, and sample pretreatment, thereby altering metal speciation. a critical factor for determining metal toxicity. In this study, we utilized carbon-fiber microelectrodes (CFMs) coupled with fast-scan cyclic voltammetry (FSCV) for rapid electrochemical detection of arsenite in tris buffer that mimics artificial cerebellum fluid. Because arsenic species' redox chemistry depends on the pH, we conducted an in-depth pH study to explain the sensor of our response under different acidic and basic conditions. We constructed calibration curves in both basic and acidic media to obtain excellent limits of detection and sensitivities. Furthermore, we conducted a selectivity test and found that our optimized parameters for basic and acidic media are specific for arsenite. To our knowledge, this is the fastest electrochemical sensor available to detect arsenite. Our preliminary data showcases the power of our sensor, which will be developed as a future in vivo arsenite sensor. [ABSTRACT FROM AUTHOR]

In the United States, there is a gap between the way that sociologists, psychologists, legal scholars, and advocates define domestic violence and the way that criminal laws define domestic violence. Experts largely agree: domestic violence occurs when a partner exercises continuous power and control over the other. In this view, domestic violence occurs via a pattern of abusive behaviors that unfolds over time, and its manifestations include both physically-violent and emotionally-abusive behaviors. In contrast, criminal statutes throughout the United States continue to conceptualize domestic violence as single acts of physical violence or threats of physical violence. During the past several years, England and Wales, Ireland, and Scotland have passed laws that have attempted to bridge this gap in their own societies. The enactment of these laws abroad--and the fact that legislatures are considering similar laws in other jurisdictions, including the United States--provides a timely opportunity to analyze whether state legislatures should adopt similar laws here. This Comment argues that states should adopt domestic violence laws similar to the ones passed abroad. First, it explains why this gap between the criminal law and other understandings of domestic violence emerged, what it looks like in practice, and what its consequences are for victims throughout their experience with the criminal justice system. Second, it draws attention to the ways in which both the legislature and the criminal justice system are growing increasingly comfortable with defining and prosecuting crimes as courses of conduct. Based on the conduct covered and the harm addressed under these already existing laws, introducing similar laws in the domestic violence context would be a natural next step. Third, it evaluates course-ofconduct laws recently passed in Scotland, Ireland, and England and Wales that have attempted to close this gap. Finally, it recommends that states pass course-of-conduct domestic violence statutes, using Scotland's law as a model. [ABSTRACT FROM AUTHOR]

The current study examined whether associations between functions of aggression (proactive and reactive) and peer victimization (physical and relational) were moderated by parental psychological control in a sample of elementary school-aged children. Analyses were based on a sample of 279 children in grades three through five. Data was collected in the fall and spring of a single academic year. Peer victimization was assessed through child- and teacher-report, and functions of aggression and parental psychological control were measured through child-report. Multiple group models, with student sex as the grouping variable, were estimated to address study hypotheses. Findings from multiple group path models revealed significant effects for boys only. For boys who reported a high level of parental psychological control, proactive aggression was a negative predictor of child-reported physical victimization. Additionally, parental psychological control moderated the association between boys' reactive aggression and teacher-reported relational victimization. At low levels of parental psychological control, reactive aggression was a positive predictor of relational victimization whereas reactive aggression was a negative predictor of peer victimization at high levels of psychological control. Our results suggest that for boys who endorse a high level of parental psychological control, aggression is negatively associated with peer victimization. We argue that children who experience a high level of parental psychological control are more likely to apply those same strategies in their peer relationships, which makes them less likely to be targets of relational and physical victimization. This study helps inform our understanding of the role of parental psychological control in the relation between aggression and peer relationship difficulties. [ABSTRACT FROM AUTHOR]

In this paper, an efficiency map is created for a double-acting, single-rod hydraulic-actuator using a critically centered four-way spool valve and a load-sensing pump. The purpose of this research is to provide an understanding of the performance of a valve-controlled hydraulic actuator under all operating conditions. This paper considers a four-quadrant set of operating conditions, where each quadrant represents a different combination of actuator retraction or extension and overrunning or resistive loading. This four-quadrant efficiency map is the first presentation of its kind in the literature, and clearly demonstrates the performance characteristics and limitations for this hydraulic system. For its most common operation of an actuator extending under a resistive load, the map shows that this system can operate at over 82% efficiency and can move large loads. The map also shows physical limitations for the system, such as maximum pressure limits, maximum displacement limits, and valve limits. The efficiency map is plotted in nondimensional form, which presents the most general understanding of system performance and also allows dimensional values to be reconstructed for a similar system of any size. [ABSTRACT FROM AUTHOR]

Simple Summary: Pseudokinases have evolved from conventional kinases and differ from them in their inability to phosphorylate their substrates. The Tribbles pseudokinases have evolved from the CAMK family of kinases and include three members: Tribbles 1, 2, and 3. Tribbles 1, which evolved later in metazoan lineage, appears to have a regulatory function. It interacts with a variety of substrates through different domains embedded in its molecular structure. Each interaction regulates cellular processes involved in cell division, survival, and metabolism. These processes also extrapolate to cancer development and other diseases. Based on its involvement in disorders and therapy resistance, it can be considered a potential candidate for drug development. The improved knowledge about its function can be utilized to design small-molecule inhibitors against TRIB1. Pseudokinases are catalytically inactive proteins in the human genome that lack the ability to transfer phosphate from ATP to their substrates. The Tribbles family of pseudokinases contains three members: Tribbles 1, 2, and 3. Tribbles 1 has recently gained importance because of its involvement in various diseases, including cancer. It acts as a scaffolding protein that brings about the degradation of its substrate proteins, such as C/EBPα/β, MLXIPL, and RAR/RXRα, among others, via the ubiquitin proteasome system. It also serves as an adapter protein, which sequesters different protein molecules and activates their downstream signaling, leading to processes, such as cell survival, cell proliferation, and lipid metabolism. It has been implicated in cancers such as AML, prostate cancer, breast cancer, CRC, HCC, and glioma, where it activates oncogenic signaling pathways such as PI3K-AKT and MAPK and inhibits the anti-tumor function of p53. TRIB1 also causes treatment resistance in cancers such as NSCLC, breast cancer, glioma, and promyelocytic leukemia. All these effects make TRIB1 a potential drug target. However, the lack of a catalytic domain renders TRIB1 "undruggable", but knowledge about its structure, conformational changes during substrate binding, and substrate binding sites provides an opportunity to design small-molecule inhibitors against specific TRIB1 interactions. [ABSTRACT FROM AUTHOR]

Highlights • The density of states for heavy paraffinic oil showed small diffusive behavior. • The secondary neutron distributions broaden with decreasing incident neutron energy. • No material difference was found between the liquid and solid treatments. Abstract Base oil lubricants are prevalent in many mechanical systems and can have a wide range of chemical compositions. Their carbon numbers generally span from C 20–40 , and they are often classified by their predominant molecular species (e.g., paraffinic, naphthenic). These heavy, viscous fluids are of interest when used in or around nuclear fuel cycle facilities, where they may influence the local neutronic environment. Furthermore, variations in molecular structure impact the oil's dynamic properties and render the modeling process a challenging endeavor. In this work, a model for a specific paraffinic oil was developed for obtaining the vibrational/translational density of states (DOS) for hydrogen and carbon, the primary and secondary scattering species, respectively. The DOS was subsequently used to generate the thermal scattering law (TSL). The molecular ensemble, constructed using the MedeA material design platform, was benchmarked using available static and dynamic properties (i.e., density, viscosity, viscosity index, diffusivity). All simulations were performed using the LAMMPS code, and the COMPASS force field, a semi-empirical molecular potential, was selected as a suitable representation of the system dynamics. Additionally, a modified version of the nuclear data processing code, NJOY, was employed to more accurately treat a viscous fluid. Through this investigation, the viscous behavior characteristic of a heavy paraffinic oil was captured and was found to minimally impact the TSL when compared to the solid approximation. [ABSTRACT FROM AUTHOR]

This paper has been written to develop closed-form equations for describing the theoretical displacement of a check-valve type, digital displacement pump. In theory, the digital displacement pump is used to alter the apparent volumetric displacement of the machine by short circuiting the flow path for reciprocating pistons within the machine that would ordinarily deliver a full volumetric flow rate to the discharge side of the pump. The short circuiting for the pistons is achieved by opening and closing a digital valve connected to each piston chamber at a desired time during the kinematic cycle for each reciprocating piston. Experience with these machines has shown that the expected volumetric displacement for the machine tends to decrease with pressure. This paper presents a theoretical explanation for the reduced volumetric displacement of the pump and quantifies the expected behavior based upon the digital valve command, the residual volume of fluid within a single piston chamber, and the fluid bulk modulus-of-elasticity. In summary, it shown that the apparent volumetric displacement of the machine may be reduced by as much as 10% for high-displacement commands and by as much as 30% for low-displacement commands. [ABSTRACT FROM AUTHOR]

The theme of sacrifice recurs in religious literature of many traditions, times, and places, and notions of parental sacrifice are even more common. But tales of human sacrifice are almost unheard of. Among the sacrifices parents make, the sacrifice of a child is the most unlikely; why would a deity demand such an offering, and what does that demand tell us about the deity's followers? Through skillful use of social inversions, bībhatsa rasa, and sacrifice, Rūparāma Cakravartī weaves a masterful tale early in his epic the Dharmamaṅgala which sets the tone for the rest of the epic and prepares his readers for the wonders to follow. [ABSTRACT FROM AUTHOR]

The objectives of this research are to explore the inertial-torque characteristics of an inline, internal combustion engine with connecting-rod joints that are evenly spaced about the centerline of the crankshaft, and to evaluate the goodness of a mass approximation that is customarily used in machine design textbooks. In this research, the number of pistons within the internal combustion engine is varied from 1 to 8. In order to generalize the results, the inertial-torque equations are nondimensionalized and shown to depend upon only four nondimensional groups, all related to the mass and geometry properties of the connecting rod. As shown in this research, the inertial-torque imbalance is greatest for an engine with two pistons, and that a dramatic reduction in the torque imbalance may be obtained for engine designs that use four or more pistons. It is also shown in this paper that the customary mass approximations for the connecting rod may be used to simplify the analysis for all engine designs without a significant loss of modeling accuracy. [ABSTRACT FROM AUTHOR]

This study examined whether social preference was a mechanism that explained the relation between proactive and reactive aggression and peer victimization. Participants were 494 children in grades 2-5. Proactive and reactive aggression was assessed via a self-report measure and indices of social preference and peer victimization were assessed via a peer nomination inventory. Data was collected during the fall and spring of two academic years. The relations among aggression, social preference, and peer victimization varied as a function of aggression and gender. For girls, reactive aggression was a significant negative predictor of social preference. Findings also revealed social preference mediated the relation between reactive aggression and peer victimization for girls. This pathway did not hold for boys. There was some evidence that proactive aggression was negatively associated with peer victimization, but only for girls. Findings from the current study suggest social preference may be a key mechanism through which reactive aggression is associated with future victimization for girls. Boys' aggression was not related to subsequent peer victimization. Future research and intervention efforts should consider gender differences and the function of aggression when investigating children's peer victimization experiences. [ABSTRACT FROM AUTHOR]

In this technical brief, the authors compare the torque capacity of a magnetorheological (MR) fluid brake with a conventional frictional disk brake. In the development of the torque models for both brakes, a mathematical expression for the compared torque ratio is presented. For the frictional disk brake, constant pressure and constant wear theories are considered, while static torque of the MR fluid brake is considered for comparison purpose only. Throughout the analysis, the outer radius of the compared brakes is assumed to be the same to ensure similarity of size, while the inner radius is selected to achieve maximum values of braking torque for both brake designs. Reasonable values of design variables for each brake are obtained from references and adopted in this study for making comparisons between the two designs. In conclusion, it is shown that the torque capacity for a frictional disk brake is 10-18 times greater than the torque capacity for a MR fluid brake of similar size. [ABSTRACT FROM AUTHOR]

This article explores the implications of early Buddhist and Christian textual analyses of gender and sex for contemporary questions about gender and physical bodies. One of the tenets of contemporary studies of gender and sexuality is the unmooring of the category of gender from the biologically identifiable and sexed bodies. Christian literature reveals a binary view of sex and gender that allowed women only very limited access to spiritual training and community. The Pāli canon and commentarial traditions, in contrast, draw on both vinaya legal and abhidhamma analytic traditions to lay out a relationship between biologically sexed bodies and gender that is not, fundamentally, essentialist yet still retains an analysis of material bodies and sex. Tracing the actual passages through the commentaries on one vinaya passage, this essay shows how the logic of vinaya and abhidhamma analyses of physical bodies, gender, and behavior is both unique to each genre while being used by commentators to explain the difference between male and female bodies and gender. At the same time, this article confirms recent scholarship that argues the Pāli commentaries are markedly sexist in their devaluation of women and female gender where the Pāli canon is not. Practitioners of both Pāli Buddhism and early Christianity included monastics, male and female. In both communities, the sexes practiced separately, and the presence of one in a locus reserved for the other would be cause for consternation and concern. Despite many obstacles to women participating with the male monastics, textual evidence of that very situation abounds in both traditions. Its occurrence, however, was recognized and handled quite differently among Buddhists than among Christians. For the Buddhist material we discuss herein, the context is perceived as spontaneous sex change. For the Christian material, the context is that of transvestite female saints. We will consider first the Buddhist materials, then the early Christian, and finally, draw some comparative conclusions. [ABSTRACT FROM AUTHOR]

In this paper, a simple feedback linearization method is used to improve the tracking performance of a linear hydraulic-actuator. This research uses an open-centered four-way valve to control the displacement of the hydraulic actuator, based upon an input command from the operator. In this research, the operator is modeled as a first-order system with a bandwidth frequency of 2 Hz. The feedback linearization method is used to adjust the operator input based on the measurement of fluid pressure on only one side of the actuator and the pump pressure that supplies the valve. No other sensing is needed. Using this approach, the R-squared value for tracking a sinusoidal displacement of the actuator and the bandwidth frequency of the actuator are increased. Furthermore, it is shown that the feedback linearization method reduces and nearly eliminates the load dependence of the tracking response, which means that operators should have less difficulty learning how to operate the machine over a wide range of conditions, and the overall productivity of the machine should go up. In summary, the elegance of this model is found in the fact that it is very simple to implement and that the alterations in output performance are greatly enhanced. [ABSTRACT FROM AUTHOR]

Pressure-compensated pumps are routinely used for supplying fluid power for hydraulic control systems. These pumps traditionally exhibit significant overshoot and oscillation before reaching a steady-state pressure condition, thus requiring the use of downstream safety valves to prevent over pressurization. In addition to over pressurizing the hydraulic control system, the response of the traditional pressure-compensated pump often induces excessive noise and creates instability for other components within the system. In this paper, a nontraditional pressure-compensated hydraulic pump is studied based upon the paradigm that has been offered by diesel-engine technology. This technology uses an inlet-metered pump to provide pressurized fuel for the high-pressure, fuel-injector rail. The analysis of this paper shows that a system of this type may be used to produce a first-order pressure response with no overshoot and oscillation, and that the characteristic time constant and settling time may be designed by specifying parameters that are identified in this research. The problem of cavitation damage is also discussed based upon preliminary testing done at the University of Missouri, and it is suggested that by using hardened machine parts cavitation damage may be prevented in these machines. In conclusion, this paper shows that continued development of the inlet-metered pump may be warranted for those applications where pressure overshoot and oscillation cannot be tolerated due to safety, noise, or other dynamical considerations. [ABSTRACT FROM AUTHOR]

This paper describes modifications to the Matrix Power Control Algorithm (MPCA) to improve convergence for Random Vibration Control (RVC) testing. In particular, this paper presents Multiple-Input Multiple-Output (MIMO) implementations of MPCA in simulation and experiment. An Euler–Bernoulli beam model was simulated with applied base excitations and the Box Assembly with Removable Component (BARC) was used in experiment to validate results. The Bayesian optimization package Dragonfly was used to optimize control parameters. Additionally, a moving-average was employed and optimized to improve the measured response feedback for MPCA, reduce the number of averages needed to be taken between control updates, and further improve convergence. The key results of this paper show that the performance of MPCA can be improved by tuning the control parameters and by applying an optimized moving-average. Furthermore, it is demonstrated that convergence can be achieved within 12 drive-frames, which greatly enhances vibration control capability. [ABSTRACT FROM AUTHOR]

This paper provides a new method for matching dominant features of Frequency Response Functions (FRFs). In particular, this paper proposes a slicing and shifting method where the key features (in this case, resonant amplitudes) of a baseline FRF are compared with a similar FRF using cross-correlation and a Log-Frequency Shift (LFS). The goal is to provide an alternative to classic point-to-point methods for FRF comparison and instead to match the dominant features of two FRFs in a way similar to visual inspection. This enables existing FRF comparison metrics to then be applied with greater fidelity. Additionally, this paper introduces the Phase Similarity Metric (PSM) for comparing phases of two FRFs and illustrates the improvement of using LFS for phase comparisons as well. This paper uses a cantilever beam experiment in multiple configurations to provide a benchmark case for FRF comparison improvements. • Point-to-point frequency comparisons for similar dynamic systems are insufficient. • Frequency characteristics are often shifted nonlinearly. • Log-frequency shifting can be used to overlap similar frequency behaviors. • Existing frequency comparison techniques can be applied with greater fidelity. [ABSTRACT FROM AUTHOR]

The treatment of war wounds is an ancient art, constantly refined to reflect improvements in weapons technology, transportation, antiseptic practices, and surgical techniques. Throughout most of the history of warfare, more soldiers died from disease than combat wounds, and misconceptions regarding the best timing and mode of treatment for injuries often resulted in more harm than good. Since the 19th century, mortality from war wounds steadily decreased as surgeons on all sides of conflicts developed systems for rapidly moving the wounded from the battlefield to frontline hospitals where surgical care is delivered. We review the most important trends in US and Western military trauma management over two centuries, including the shift from primary to delayed closure in wound management, refinement of amputation techniques, advances in evacuation philosophy and technology, the development of antiseptic practices, and the use of antibiotics. We also discuss how the lessons of history are reflected in contemporary US practices in Iraq and Afghanistan. [ABSTRACT FROM AUTHOR]

Efficiency maps have long been used by engineers to understand the topographical behavior of their machinery. Most commonly, efficiency maps have been generated for internal combustion engines, where the torque-speed curve for the engine shows the wide-open-throttle line with constant efficiency lines drawn beneath this maximum operating limit. From such maps, engineers have been able to determine the most efficiency operating point for the engine, given a desired output power (torque and speed). There currently exists a great interest in using hydrostatic transmissions for improving the operating efficiency of an internal combustion engine. However, efficiency maps for hydrostatic transmissions, similar to efficiency maps for internal combustion engines, do not exist in the literature and therefore it is difficult to assess the overall efficiency gains that are achieved when using a hydrostatic transmission in these applications. This paper proposes a method for generating efficiency maps for hydrostatic transmissions, and presents a typical set of maps that may be used as a first approximation for assessing transmission efficiency. The results of this paper are nondimensional and are generalized for a transmission of any size. As shown in this research, there are regimes of transmission operation in which the efficiency is nearly independent of either the output torque, or the output speed. Furthermore, it is shown that maximum operating efficiencies typically exist at high output speeds, and mid-to-high output torques. [ABSTRACT FROM AUTHOR]

This paper proposes a scaling law for estimating the speed limitations for a family of axial-piston swash-plate type hydrostatic machines. The speed limitations for this machine are considered from three mechanical perspectives: (I) cylinder-block tipping, (2) cylinder-block filling, and (3) slipper-tipping. As shown in the results of this research, each speed limitation is scaled by the inverse of the cube root of the volumetric displacement for the new machine. In other words, small machines are shown to have a higher speed capacity than larger machines. By scaling a baseline machine using the scale laws that are presented here, a new machine may be produced that obeys a simple rule related only to the volumetric displacement of the new machine. Serendipitously, and perhaps most usefully, all three speed limitations obey the same rule! The speed limitations that are derived in this research are compared to existing industry data of currently scaled products and it is shown that the proposed scale laws correspond well with this data. [ABSTRACT FROM AUTHOR]

Abstract: Sustainable development activities are comprised of complex sets of social, economic, and ecological factors. Cross-scale knowledge and applications are increasingly valuable today in achieving successful interdisciplinary action research collaborations among universities and other stakeholders in order to understand and manage the predictable and unpredictable transformative change possibilities in social-ecological systems. This paper analyzes case studies of two complex regional social-ecological systems that illustrate the dynamic interactions between human societies and natural systems. The framework of panarchy, which integrates the cross-scales and domains of social, economic, and environmental systems, is incorporated as a means of examining the dimensions of adaptability and resilience, and the evolution of these social-ecological systems as stakeholder learning networks. The practical intent of using case studies is threefold: 1. To demonstrate how a holistic synthesis of these multi-domain frameworks can enrich descriptive and prescriptive analyses of social-ecological systems phenomena, 2. To make these integrative frameworks and analytical tools more readily useful for students, university educators, researchers and academic-practitioners, to incorporate into interdisciplinary curricula, teaching, research and practice, and 3. To offer these cross-domain tools to facilitate integrative action research collaborative partnerships among educators, researchers, academic-practitioners, and other social-ecological system stakeholders. [Copyright &y& Elsevier]

This research shows that an existing rear-wheel drive vehicle may be easily retrofitted with a continuously variable-transmission for the purposes of reducing the overall fuel consumption of the automobile. The retrofit-ability of this transmission is the primary advantage that it exhibits over other continuously variable-transmissions. By retrofitting this vehicle with the transmission components that are shown in this paper, the existing vehicle transmission continues to be used with the exception of the driveshaft which is replaced by the hydraulic continuously variable-transmission itself. Using a standard model for the vehicle dynamics, this paper presents a detailed analysis for the speed ratios of all gears, and shows how to specify the size of the hydraulic pump and motor to insure a safe pressure level of operation. To illustrate the usefulness of this method, an actual transmission is designed for the 1997 Ford Ranger, and the range of adjustability for the transmission is evaluated by seeking to hold the engine speed constant for a ramped speed output of the vehicle. In conclusion, this research shows that the design methodology is valid and that only minor errors in engine speed are observed during low ground velocities for the vehicle. [ABSTRACT FROM AUTHOR]

Power density is an assumed attribute of an axial-piston swash-plate type hydrostatic machine. As such, very little research has been conducted to examine the nature and limit of this machine's power density and the literature is all but void of this important topic. This paper is being written to fill this void, and to provide a thorough analysis of the machine's power density. This paper is also aimed at identifying the most significant parameters that may be adjusted to increase the power density for a typical machine. As shown in this research, the power density of an axial-piston machine depends upon four dimensionless quantities that are characteristic of the machine's rotating group. As it turns out, the allowable stress for the cylinder block is the most sensitive parameter that may be adjusted for increasing the power density of this machine. It is further shown that increasing the machine's swash-plate angle, and reducing the minimum overhang length for the pistons, will have a significant impact on the power density as well. It is significant to note that altering the number of pistons in the design has essentially no impact on the power density of the machine and therefore the selection of this design parameter must be based upon other design objectives. In conclusion, it is shown in this paper that the power density of a typical machine may be increased by as much as 64% by altering a few of these parameters within a realistic realm of constraint. [ABSTRACT FROM AUTHOR]

A challenge facing military caregivers is the presence of multidrug-resistant infection in extremity wounds. Most frequently identified resistant strains are methicillin-resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae (KP), Pseudomonas aeruginosa (PA), and Acinetobacter baumannii (AB). We adapted an existing osteomyelitis model to simulate an infected extremity wound for antibiotic testing. New Zealand White Rabbits (n = 95) were divided into 6 inoculation groups for infection with MRSA, KP, PA, and AB alone, and in multibacteria infections. Sodium morrhuate was injected into the left tibia to simulate blast wound trauma, then the respective bacteria or combination of pathogens, and finally sterile saline were injected. Colony-forming units for the mono-organism groups showed that AB, KP, or PA alone at 107 colony-forming units per mL (CFUs/mL) was effective for rabbit osteomyelitis induction. Colony-forming units for the multiorganism groups showed that the combination of AB (107 CFUs/mL)/KP (10v CFUs/mL)/PA (107 CFUs/mL)/MRSA (105 CFUs/mL) yielded a 100% osteomyelitis induction rate. At 8 weeks, however, only one mono-bacterial group and one multibacterial group showed significant radiographic improvement (p < 0.05). The rabbit model of osteomyelitis can be adapted to study infected blast wounds typical of those seen in veterans. To our knowledge, this is the first demonstration of the model simulating multibacterial infections with multidrug-resistant organisms. [ABSTRACT FROM AUTHOR]

This biographical sketch on Ruth Jackson corresponds to the historic text, The Classic: The Cervical Syndrome, available at DOI 10.1007/s11999-010-1278-8 . [ABSTRACT FROM AUTHOR]

This biographical sketch of Royal Whitman corresponds to the historic text, The Classic: A Study of the Weak Foot, with Reference to its Causes, its Diagnosis, and its Cure; with an Analysis of a Thousand Cases of So-Called Flat-Foot, available at DOI 10.1007/s11999-009-1130-1 . [ABSTRACT FROM AUTHOR]

Today's business students will chart their career paths through a rapidly changing, highly interdependent world of relationships and networks. In addition to traditional business school knowledge, students need cognitive, behavioral and affective skill sets, along with opportunities for civic engagement. This exploratory study of course-embedded service-learning, incorporating Cherniss and Goleman's emotional intelligence construct, found that students' service-learning experiences tapped and fostered the personal and social emotional intelligence competencies associated with professional effectiveness. Incorporating service-learning, with a focus on increasing emotional intelligence, offers a promising approach for business schools to reinforce and increase students' civic values as well as to enrich their personal and inter-personal emotional intelligence insights and skill development. This approach will strengthen the curricula and teaching practices of business schools to better prepare students for their roles as responsible leaders in creating and managing sustainable businesses and partnerships for our global-collective future. [ABSTRACT FROM AUTHOR]

The objective of this paper is to experimentally investigate the significance of the pressure transient flow force acting on hydraulic spool valves. In the past, this flow force effect has been routinely neglected due to its assumed small size. Through analytical and experimental methods, this research shows that flow forces due to pressure transient effects can be comparable in magnitude to the steady flow forces acting on the valve and that the past tradition of neglecting this effect may not always be justified. The paper also shows that the traditional steady flow force model does a fairly good job predicting the steady flow forces on the valve, but more research must be done to develop a good modelfor pressure transientflowforces. [ABSTRACT FROM AUTHOR]

This biographical sketch on Fuller Albright corresponds to the historic text, The Classic: The Metabolic Effects of Steroid Hormones in Osteoporosis, available at DOI . [ABSTRACT FROM AUTHOR]

Abstract: Sustainability strategies create many synergistic effects for SMEs working collaboratively, as well as systemic benefits for the commons. After setting forth the business case for sustainable SMEs, and considering SME sustainability advantages in contrast to MNEs, this paper discusses several different incentives for SMEs to optimize sustainability: (1) becoming valuable sustainable investment targets for larger firms; (2) creating highly competitive networks of sustainable SMEs in market spaces where large enterprises are less successful; (3) becoming highly efficient suppliers in global supply chains through sustainable practices. While several successful models of the sustainable SME are evolving, it may be that networks of SMEs will become essential for addressing the systemic problems that underlie industrial ecology, enterprise resilience, and global supply chain sustainability. SMEs represent the majority of all enterprises, and rapidly evolving communication technologies allow for various routes of network formation. [Copyright &y& Elsevier]

Abstract: The utility of applying a virtual learning network model for illustrating successful triple bottom line transitions—one that integrates the ecological, economic, and social dimensions of cleaner production—is illustrated by a successful approach to promote “green chemistry” in the North Carolina textile wet-processing industry. This case is unique in demonstrating the quality of this process to develop cleaner production methods; it shows how reducing aquatic toxicity and harmful environmental effects in a “real world” situation depends on successful efforts to build, manage, and maintain an inter-organizational network of multiple stakeholders. This network included industries in the textile production chain, their local and provincial communities, regulators and policy makers. The utilization of cases such as this in the business school pedagogy expands understanding of the role of sustainable practices in enterprise management. The value of this specific case in promoting the understanding of such networks was demonstrated in a recent MBA experience when students trained in these areas linked diverse stakeholders and applied the triple bottom line perspective in traditional business simulation exercises in an MBA capstone course. Such cases can also effectively prepare students for actual challenges facing managers in the rapidly changing business environment. [Copyright &y& Elsevier]

Adaptive ecosystem management (AEM) requires building and managing an interorganizational network of stakeholders to conserve ecosystem integrity while sustaining ecosystem services. This paper demonstrates the usefulness of applying the concepts of interorganizational networks and learning organizations to AEM. A case study of the lower Roanoke River in North Carolina illustrates how an AEM network can evolve to guide stakeholders in creating a shared framework for generative learning, consensus building through collaboration, and decision making. Environmental professionals can use this framework to guide institutional arrangements and to coordinate the systematic development of cohesive interorganizational AEM networks. [ABSTRACT FROM AUTHOR]

The objective of this paper is to analyze the uncertainty associated with pump efficiency measurements and to determine reasonable confidence intervals for these data. In the past, many industrial sales and some pieces of academic research have been based upon the experimental data of pump efficiencies; yet few have questioned the accuracy of the experimental data and no one has provided a confidence interval which reflects the range of uncertainty in the measurement. In this paper a method for calculating this confidence interval is presented and it is shown that substantially large confidence intervals exist within the testing results of a pump. Furthermore, it is recommended that these confidence intervals be included with the efficiency data whenever it is reported. [ABSTRACT FROM AUTHOR]

Background. Previous research has yielded inconsistent findings on the relationship between personality characteristics and chronic pain. The present study examines measures of alexithymia, somatosensory amplification, attachment, counterdependency, and emotional distress in 140 consecutive general medical outpatients seen in psychiatric consultation. Methods. Forty-five subjects having no chronic pain (NP) were compared to 49 subjects with chronic pain restricted to their back and/or extremities (BE) and with 46 subjects having pain involving other regions of the body (OP). Results. Findings demonstrated marked counterdependency traits in the BE group relative to the other two groups. By contrast, traits of alexithymia and somatosensory amplification, insecure attachment, and a high level of emotional distress characterized the OP group. A multiple logistic regression model combining counterdependency and secure attachment was 86% accurate in predicting BE (c=0.86). Conclusions. The study’s findings suggest that personality traits vary according to chronic pain location, although the nature of the relationship still needs to be determined. [ABSTRACT FROM AUTHOR]

The Forest Service's new planning regulation "locks the back door." It replaces post-decisional appeals of forest plans with a "predecisional objection process" within a framework of collaborative planning. This article examines the agency's rationale for eliminating postdecisional appeals of forest plans, and explores the potential implications of this policy initiative. Viewing appeals as a mechanism of democratic accountability, the analysis examines environmentalists' use of the appeals process, and the effects of appeals on Forest Service land management and policy. The article concludes with observations about the role of conflict and the legitimacy of appeals as one avenue of democratic participation. [ABSTRACT FROM AUTHOR]

Examines the control and containment forces acting on the swash plate of an axialpiston pump. Analysis of a secondary swash-plate angle that is occasionally used in aerospace pump applications; Investigation of the dynamic characteristics of the control and containment forces by deriving instantaneous and average equations of motion for the swash plate.

Studies the theoretical flow ripple of an external gear pump for pumps of similar size using different numbers of teeth on the driving and driven gears. Derivation of the flow ripple equation; Significance of the instantaneous length of action within the gear mesh; Presentation of a numerical and a closed-form approximation; Utilization of a fast Fourier transform analysis for identifying the harmonic frequencies and amplitudes of the flow pulse; Advantages of designing an external gear pump with a large number of teeth on the driving gear and a fewer number of teeth on the driven gear.

Discusses the improved volumetric-efficiency of an axial-piston pump utilizing a trapped-volume design. Function of swash-plate type axial-piston pumps for hydraulic circuitry; Advantages and disadvantages of the machine; Introduction of a volumetric loss by standard valve-plate design.

Presents a nontraditional pump design utilizing a piston-bore spring. Function of the piston-bore spring in the nontraditional pump design; Analysis in describing the effect of the spring in the control torque; Elimination of the crossover from a stroke increasing swash-plate torque to a stroke decreasing swash-plate torque.

Presents a case study of union-management-employee partnership within the food service group of a teaching hospital. Challenges facing healthcare providers; Background of the case study; Benefits of the focus group process; Reasons for the success of the partnership.

Examines the idealized and actual flow-ripple of an axial-piston swash-plate type hydrostatic pump. Assumption of zero leakage in the pump and incompressible fluid; Derivation of closed-form expressions which describe the characteristics of the idealized flow-ripple of the pump; Feasibility of a pump designed with an even number of pistons in terms of flow ripple.

Studies the physics that contribute to the tipping of cylinder blocks within an axial-piston swash-plate type machine. Mechanical analysis of a cylinder block; Tipping criterion based upon the centroidal location of the force reaction between the cylinder block and the valve plate; Cylinder block free-body diagram.