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This is a review of the activities and successes of the 43rd residential JACT Latin Summer School, run in July 2023. Specifically, it covers our typical teaching arrangement, lectures, trips and events and acknowledges the generosity of our sponsors. [ABSTRACT FROM AUTHOR]

This is a review of the activities and successes of the 42nd residential JACT Latin Summer School, run in July 2022. Specifically, it covers our typical teaching arrangement, lectures, trips and events and acknowledges the generosity of our sponsors. [ABSTRACT FROM AUTHOR]

Until recently Java programmers have had three options when wishing to access the XML infoset: they could use DOM, JDOM, or SAX. With the release of the JSR 1 73 […]

I'm sending you guys the receipt for my recent dentist bill. I had to have two teeth fixed after my jaw hit the ground when I saw the Challenger concept […]

Departments Lower lakes and their ports Really enjoyed the story about the car ferries ["Rails Across the Lower Lakes", page 16] - until I tried to correlate what the story was saying with what the map was showing. In the early 1970s, I had planned an entire train excursion in the South just so I could make a round trip on the triweekly Special from Salisbury. Although the SN was a WP subsidiary, and any profit made off this particular train ended up in the WP ledger book in its San Francisco offices, strictly speaking it is an SN train. The sad news about J. David Ingles is like a conductor's clarion call for the ultimate destination of a long train journey. [Extracted from the article]

Sensorimotor synchronization (SMS) is frequently dependent on coordination of excitatory and inhibitory activity across hemispheres, as well as the cognitive control over environmental distractors. However, the timing (motor planning versus execution) and cortical regions involved in these processes remain actively debated. Functional magnetic resonance imaging data were therefore analyzed from 34 strongly right-handed healthy adults performing a cued (to initiate motor planning) SMS task with either their right or left hand (motor execution phase) based on spatially congruent or incongruent visual stimuli. Behavioral effects of incongruent stimuli were limited to the first stimulus. Functionally, greater activation was observed in left sensorimotor cortex (SMC) and right cerebellar Lobule V for congruent versus incongruent stimuli. A negative blood-oxygen level dependent response, a putative marker of neural inhibition, was present in bilateral SMC, right supplemental motor area (SMA) and bilateral cerebellar Lobule V during the motor planning, but not execution phase. The magnitude of the inhibitory response was greater in right cortical regions and cerebellar Lobule V. Homologue connectivity was associated with inhibitory activity in the right SMA, suggesting that individual differences in intrinsic connectivity may mediate transcallosal inhibition. In summary, results suggest increased inhibition (i.e., greater negative BOLD response) within the right relative to left hemisphere, which was released once motor programs were executed. Both task and intrinsic functional connectivity results highlight a critical role of the left SMA in interhemispheric inhibition and motor planning.

Allylindium halides are valuable allylating reagents, which can even be applied in aqueous solutions. Previous 1H NMR spectroscopic investigations suggested that these reagents are stable for several hours in D2O, whereas ESI-mass spectrometric experiments in H2O pointed to much shorter lifetimes. To resolve this seeming discrepancy, the present study systematically examines the solvolysis of allylindium iodide in H2O, D2O, and mixtures thereof by both analytical methods. Kinetic measurements find a large kinetic isotope effect (KIE = 12.0 ± 1.5 at 298 K), which fully explains the different behavior in H2O and D2O. Moreover, new intact and partially hydrolyzed allylindium intermediates are detected. Additional experiments on solutions of allylindium iodide in CH3OH, CH3OD, and EtOH observe ions identical or similar to those present in aqueous solutions, but determine a somewhat smaller kinetic isotope effect.

A positive trend in time has been noted in the seasonal amplitude of surface ocean pCO2over much of the oceans, which is expected to have detrimental impacts on marine ecosystems. To determine whether or not this has an anthropogenic cause, this study investigates historical climate simulations from the Detection and Attribution Model Intercomparison Project with and without anthropogenic forcing. The simulations with anthropogenic forcing show clear evidence of positive trends, whereas the simulations with constant preindustrial atmospheric CO2and natural external forcing give only negligible trends. A statistical analysis of five zonal latitudinal bands reveals that the trends detected over 1990–2014 in an ensemble of six observational products are attributable to anthropogenic forcing in mid‐latitudes (40°N–10°N, 10°S–40°S), while no trends are detected and modeled in the tropics and the Southern Ocean. Most models fail to represent the sign of the observed climatological mean seasonal cycle difference in high latitudes. Global warming due to fossil fuel use is unequivocal and documented by long records. In contrast, measurements for other important Earth system parameters are only available over recent decades. A short record length makes the attribution of observed trends to human‐induced forcing challenging. Trends may be hard to identify due to chaotic Earth system variability. The seasonal amplitude of the partial pressure of CO2(pCO2) in the surface ocean is observed to increase, with global‐scale data available since 1990. A continued increase is expected to have negative impacts on fish as the amplified seasonality leads to very high pCO2, hindering the uptake of oxygen during breathing. Here, we analyze pCO2from climate model historical simulations forced by human‐caused and natural factors versus simulations with natural factors only. The results allow us to firmly attribute the observed trend in the pCO2seasonal amplitude in mid‐latitudes to human activities. Trends in seasonal amplitudes of surface ocean pCO2are analyzed in observations and CMIP6 simulations with/without anthropogenic forcingApplying an Analysis of Covariance, the observed trends in mid‐latitude regions are firmly attributed to anthropogenic forcingThe model ensemble shows large data‐model and model‐model discrepancies in the pCO2seasonal cycle, in particular in high‐latitude regions Trends in seasonal amplitudes of surface ocean pCO2are analyzed in observations and CMIP6 simulations with/without anthropogenic forcing Applying an Analysis of Covariance, the observed trends in mid‐latitude regions are firmly attributed to anthropogenic forcing The model ensemble shows large data‐model and model‐model discrepancies in the pCO2seasonal cycle, in particular in high‐latitude regions

Individuals with acute and chronic traumatic brain injury (TBI) are associated with unique white matter (WM) structural abnormalities, including fractional anisotropy (FA) differences. Our research group previously used FA as a feature in a linear support vector machine (SVM) pattern classifier, observing high classification between individuals with and without acute TBI (i.e., an area under the curve [AUC] value of 75.50%). However, it is not known whether FA could similarly classify between individuals with and without history of chronic TBI. Here, we attempted to replicate our previous work with a new sample, investigating whether FA could similarly classify between incarcerated men with (n = 80) and without (n = 80) self-reported history of chronic TBI. Additionally, given limitations associated with FA, including underestimation of FA values in WM tracts containing crossing fibers, we extended upon our previous study by incorporating neurite orientation dispersion and density imaging (NODDI) metrics, including orientation dispersion (ODI) and isotropic volume (Viso). A linear SVM based classification approach, similar to our previous study, was incorporated here to classify between individuals with and without self-reported chronic TBI using FA and NODDI metrics as separate features. Overall classification rates were similar when incorporating FA and NODDI ODI metrics as features (AUC: 82.50%). Additionally, NODDI-based metrics provided the highest sensitivity (ODI: 85.00%) and specificity (Viso: 82.50%) rates. The current study serves as a replication and extension of our previous study, observing that multiple diffusion MRI metrics can reliably classify between individuals with and without self-reported history of chronic TBI.

New functionally gradient materials for coating twin-screw extruder barrels to ensure maximum wear resistance are described.

Components shaped from powders can be produced in high volumes using the powder injection molding process (PIM). The development of metal and ceramic powders specifically designed for use with PIM and the manufacture of multi-component binder systems which have reduced PIM's defect rates and debinding times are attracting manufacturers to PIM. Powder co-injection molding and the net-shape manufacture of fiber-reinforced ceramic components are expected to further popularize PIM.

This research investigates the high-throughput drilling of the compacted graphite iron (CGI), a high strength, lightweight material for automotive powertrain applications, at 26.5mm/s feed rate using 4mm diameter coated carbide drill. The CGI drilling experiments show that maximum 1740, 3150 and 2948 holes were drilled in two repeated tests under the dry, dry with through-the-drill compressed air, and minimum quantity lubrication (MQL) conditions. The Joule-Thomson cooling effect due to expansion of high pressure air from holes at the drill tip and mechanical effect of chip formation and evacuation are studied. Results demonstrate that high-throughput sustainable dry drilling of CGI is technically feasible.

The challenges involved in the development of ultra precision manufacturing techniques, for materials and manufacturing processing, thereby developing products, that have enhanced performance, lower cost and higher efficiency, are discussed.

This article highlights the centrality of gender for men's mental health and illustrates how it interacts with other systems of inequality. A key argument is that societal expectations of men place them at risk of depression, psychosis and suicide. An analysis of gender should therefore be the starting point for building knowledge about men's mental health difficulties. [ABSTRACT FROM AUTHOR]

This paper summarizes the advancements and challenges of minimum quantity lubrication (MQL) technology in automotive powertrain machining from both industrial and academic perspectives. MQL refers to applying a small amount of cutting fluid in the form of mist to the cutting zone rather than flooding the workpiece. Elimination of coolant systems creates significant saving from energy and equipment, the flexibility to relocate the machines, reduction of waste stream and floor space, and a cleaner and healthier work environment. Ford Motor Company has demonstrated these advantages, and currently has a total of over 400 MQL CNC machining centers in numerous global transmission and engine plants running MQL operations, with further implementation planned for new programs globally. Technical challenges to realize 100% implementation includes tool design, delivery system, chip management, and thermal related problems, particularly in high-energy density processes and difficult-to-machine metals, such as deep-hole drilling and compacted graphite iron (CGI). This paper provides a review of current status and limitations of MQL machining and highlights opportunities for research and development of the next-generation MQL technology in automotive powertrain machining.

The Sahelian drought of the 1970s–1990s was one of the largest humanitarian disasters of the past 50 years, causing up to 250,000 deaths and creating 10 million refugees. It has been attributed to natural variability, over-grazing and the impact of industrial emissions of sulphur dioxide. Each mechanism can influence the Atlantic sea surface temperature gradient, which is strongly coupled to Sahelian precipitation. We suggest that sporadic volcanic eruptions in the Northern Hemisphere also strongly influence this gradient and cause Sahelian drought. Using de-trended observations from 1900 to 2010, we show that three of the four driest Sahelian summers were preceded by substantial Northern Hemisphere volcanic eruptions. We use a state-of-the-art coupled global atmosphere–ocean model to simulate both episodic volcanic eruptions and geoengineering by continuous deliberate injection into the stratosphere. In either case, large asymmetric stratospheric aerosol loadings concentrated in the Northern Hemisphere are a harbinger of Sahelian drought whereas those concentrated in the Southern Hemisphere induce a greening of the Sahel. Further studies of the detailed regional impacts on the Sahel and other vulnerable areas are required to inform policymakers in developing careful consensual global governance before any practical solar radiation management geoengineering scheme is implemented.

Detailed battery models require mass-transport resistance parameters such as ionic conductivity and salt diffusivity. Effective transport properties can be related to the tortuosities of the porous layers containing the electrolyte. Nevertheless, relatively few direct tortuosity measurements have been performed for cathodes and for anodes. Tortuosities of several Li-ion cathode and anode films were determined using a previously developed polarization-interrupt method. Also, a new and more robust procedure using liquid gallium to delaminate electrodes from aluminum current collectors was developed and validated. This method was shown to be superior to the previous mechanical removal procedure, especially with regard to repeatability. Multiple experiments were performed to assess the effect of the carbon and binder amounts and porosity on electrode tortuosity. Results are well fit with a modified Bruggeman-type function, showing as expected that tortuosity is inversely related to porosity. Additionally, increasing the amount of carbon and binder increases the electrode tortuosity due to small particles plugging the pores.

Quantitative projections of future climate are in increasing demand from the scientific community, policymakers and other stakeholders. Climate models of varying complexity are used to make projections, but approximations and inadequacies or 'errors' in models mean that those projections are uncertain, sometimes exploring a very wide range of possible futures. Techniques for quantifying the uncertainties are described here in terms of a common framework whereby models are used to explore relationships between past climate and climate change and future projections. Model parameters may be varied to produce a range of different simulations of past climate that are then compared with observations using 'metrics'. If the model parameters can be constrained to a tighter range as a result of observational comparisons, projections can also be constrained to a tighter range. The strengths and weaknesses of different implementations are discussed.

Objectives: This study compared fentanyl vs. sufentanil in intrathecal pain pumps. H1: both reduce patient subjective pain ratings. H2: sufentanil is more effective than fentanyl. H3: overall satisfaction with pain control is greater with sufentanil.

A zero-dimensional electrochemical model of the Fe/V redox flow battery (RFB) is presented that can model RFB performance at low flow rates (<0.5 mL min[?]1 cm[?]2) and varied temperatures. The electrochemical model is appropriate for practical RFBs and provides good agreement with experimental data. In addition, a proposed non-ideal electrode model is introduced that accounts for higher voltage losses at low flow rates. Semi-quantitative operation strategies and electrode design guidelines can be obtained from the model. We found that ohmic losses associated with the electrolyte were dominating our electrode losses, which means operating the cell at higher temperature will reduce electrolyte ohmic losses and viscosity, thus leading to higher system efficiency. Thinner electrodes than the 4.5-mm-thick felt used in this study should reduce ohmic losses as well as pumping losses if the same space velocity is maintained. This electrochemical model can be easily incorporated into system-level and cost models, which will help in system optimization, system control, and pump selection and help avoid potential risks of large scale RFB system development.

This work combines experiments and computer models in order to understand the relationships between electrode microstructure and ionic transport resistances so that one may predict cell performance from fundamental principles. A scanning electron microscope (SEM) with focused ion beam (FIB) was used to image sections of commercially made porous electrodes utilizing LiCoO2 active material. The images reveal the existence of discrete porous carbon domains in the microstructure. Further experiments indicated that these carbon domains are highly tortuous and restrict to a large degree the overall ion transport in the cathode. Two types of 3D models for correlating and predicting the electrode microstructure were explored. The first, known as the dynamic particle packing (DPP) model, is based on aggregates of spheres that move collectively in response to interparticle forces. The second is a stochastic grid (SG) model closely related to Monte Carlo techniques used in statistical physics to study cooperative and competitive phase behavior. The models use a small set of fundamental interdomain and bulk interaction parameters to generate structures from a given electrode mass composition and porosity. Both models were able to semi-quantitatively reproduce experimental tortuosity measurements of cathodes at different porosity values.

This study investigates the effect of air pressure on workpiece temperature in through tool minimum quantity lubrication (MQL) deep-hole drilling. Experiments on 200 mm deep holes drilled by a 10 mm carbide drill were conducted under regular (500 kPa) and high (1000 kPa) air pressure conditions. Torque data shows that the chip clogging problem occurring under regular air pressure can be solved by the high air pressure. An inverse heat transfer method is utilized to quantify the heat fluxes and calculate the temperature distribution during drilling based on embedded thermocouples along the depth. Results show that temperature around the hole increases rapidly when the chips start accumulating in the hole under regular air pressure and cause high heat flux on the drilled hole wall surface. The high pressure condition, prevents chip accumulation, thus reducing the total heat flux.

Li-ion battery electrodes are ion-milled and prepared for three-dimensional reconstruction imaging using a focused ion beam and a method of automated serial sectioning. This tool is being developed as a means to gain additional information not typically obtained with traditional microscopy in order to improve models and further understand the structure-performance relationships. Images of the morphology acquired in such a way can be entered in a mathematical model which describes the underlying processes and physical, chemical, and electrical phenomena. Modifications to the electrode fabrication process can be made to achieve the desired morphology. This three-pronged approach provides an opportunity to develop more rigorous models and allows some predictive ability in performance of a new material or electrode film.

Die vorliegende Studie analysiert den Zusammenhang zwischen der seriellen Häufung von winterlichen extratropischen Zyklonen und der Wirbelstärkeintensität der Zyklonen sowie der Länge des Zeitintervalls, über das die Zyklonendurchgänge akkumuliert werden. Dabei wird die serielle Häufung charakterisiert durch die statistische Dispersion (dem Quotienten aus Varianz und Mittelwert) in der Anzahl der ostwärts ziehenden Zyklonen. Diese Anzahl kann durch objektive Verfolgung der Eigenschaften der 850 hPa-Wirbelstärke in NCEP-NCAR-Reanalysen ermittelt werden. Die Akkumulation der Anzahl erfolgt über disjunkte Zeitintervalle von minimal 4 Tagen bis maximal 6 Monaten (Oktober bis März) im Zeitraum von 1950 bis 2003. Die serielle Häufung ist am größten im Endgebiet des nordatlantischen Sturmkorridors (nordöstlicher Atlantik und nordwestliches Europa). Ausserdem kann ein erheblicher Zuwachs der seriellen Häufung bei stärkeren Zyklonen beobachtet werden; so wächst zum Beispiel die statistische Dispersion in der Anzahl der Zyklonen bei 3-Monats-Zeitintervallen von 1,45 für alle Zyklonen auf 1,80 für die 25 % stärksten Zyklonen an. Des weiteren wächst die statistische Dispersion etwa linear mit dem Logarithmus der Länge des Akkumulationszeitintervalls; nahe Berlin beträgt die statistische Dispersion zum Beispiel 1,08 für Wochen-, 1,33 für Monats-, und 1,45 für 3-Monats-Zeitintervalle. Sowohl die Zunahme als auch die Unsicherheit der statistischen Dispersion kann reproduziert werden mittels einfacher Poisson-Regressions-Modelle mit zeitabhängigen Raten, welche wiederum von großskaligen Telekonnektionsindizes (Nordatlantische Oszillation, Ostatlantisches Muster, Skandinavisches Muster und Ostatlantisches/Westrussisches Muster) abhängen. Die zunehmende statistische Dispersion bei starken Zyklonen kann durch die zunehmende Abhängigkeit dieser Raten von den Telekonnektionsindizes erklärt werden, wohingegen die zunehmende statistische Dispersion bei zunehmender Länge des Akkumulationszeitintervalls durch die langreichweitige serielle Korrelation der Telekonnektionsindizes erklärt wird. Zunehmende serielle Häufung bei zunehmender Zyklonenstärke und Länge des Akkumulationszeitintervalls spielt eine wichtige Rolle bei der zuverlässigen Modellierung von akkumulierten Versicherungsschäden.