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Abstract High-hazard seismic zones can remain silent over centuries with meager seismicity rates challenging our understanding of seismic processes. We focus on the comprehensive analysis of cascading episodes of swarms and seismic sequences following the 2009 L’Aquila mainshock (MW 6.3) in the southern-central Apennine that previously experienced ~ M7 earthquakes. We enhance the seismic catalog, unmasking low-magnitude seismicity down to completeness magnitude ML ~ 0, and we unveil that the microseismicity might be secondarily triggered by the L’Aquila mainshock, influencing the frictional properties in the nearby fault zones or opening fault valves generating the intense seismic activity detected from 2009 to 2013. The diffusivity, observed in the most seismic episodes, and the high Vp/Vs values (> 1.88) indicate fluid circulation promoting multilayered extensional seismicity within 11–15 km and 16–23 km depth ranges. Mapping the 3D distribution of seismicity alongside geological data reveals an evident tectonic influence, unveiling unknown geometric aspects and providing the first evidence of a NNE-dipping deformation zone bounding at depths of 11–15 km the overlying fault system. Deeper seismicity suggests a mantellic CO2 ascending shape. These findings enrich the literature on tectonic seismic swarms in extensional domains, providing essential constraints on fluid involvement in the seismic processes and contributing to forthcoming discussions on the seismotectonic setting in high-seismic-risk areas of the Apennines of Italy.

Introduction: Wide-awake local anesthesia and no tourniquet (WALANT) represents a revolutionary technique for hand surgeons who dismiss tourniquets and sedation. In this study, we present our experience with the WALANT technique in primary flexor tendon injuries of the hand. Patient and methods: This prospective research was carried out on 30 patients undergoing hand primary, flexor tendon repair surgery. Flexor tendon injury zones 2, 3, 4, and 5 were included. WALANT was prepared and injected. The tendons were surgically managed by a cruciate single cross-stitched locked 4-strand technique. The pain was assessed using a visual analog scale (VAS) score. The range of motion (ROM) of affected fingers was assessed according to the Strickland evaluation system. Results: There was a highly significant relationship between the patient's compliance with physiotherapy and obtained ROM of the affected finger with a P value

Abstract We present an analysis of magnitude clustering of microfractures inferred from acoustic emissions (AEs) during stick‐slip (SS) dynamics of faulted Westerly granite samples in frictional sliding experiments, with and without fluids, under triaxial loading with constant displacement rate. We investigate magnitude clustering in time across periods during, preceding and after macroscopic slip events on laboratory faults. Our findings reveal that magnitude clustering exists such that subsequent AEs tend to have more similar magnitudes than expected. Yet, this clustering only exists during macroscopic slip events and is strongest during major slip events in fluid‐saturated and dry samples. We demonstrate that robust magnitude clustering arises from variations in frequency‐magnitude distributions of AE events during macroscopic slip events. These temporal variations indicate a prevalence of larger AE events right after (0.3–3 s) the SS onset. Hence, magnitude clustering is a consequence of non‐stationarities.

It is now generally accepted that large earthquakes can promote eruptions at nearby volcanoes. However, the prevalence of “triggered” eruptions, as well as the distance and timescale over which triggering occurs, remain unclear. Here, we use modern global earthquake and eruption records to compare volcanic eruption rates before and after large earthquakes with the time- averaged background eruption rate. We quantify the significance of observed deviations from the average eruption rate using Monte Carlo simulations. To integrate our findings with previous eruption triggering studies, we systematically vary the earthquake magnitudes we consider, as well as the distances and timescales used to calculate eruption rates. We also investigate the effects of earthquake depth and slip orientation. Overall, we find that post-earthquake eruption rates are around 1.25 times the average eruption rate within 750 km and one year following Mw ≥ 7 earthquakes, with above-average post-earthquake eruption rates possibly lasting for two to four years. By contrast, pre-earthquake eruption rates are around 0.9 times the average eruption rate within 750 km and182 days before Mw ≥7 earthquakes. Furthermore, deep earthquakes (≥7 0km) appear to more strongly affect eruption rates than shallow earthquakes, while earthquake slip orientation is also important. Further study of the relationships reported here represents a good opportunity to improve our understanding of tectono-magmatic relationships.

In the early stages, uncontrolled groundwater extraction led to the Hangjiahu (HJH) Plain becoming one of the areas with the most severe land subsidence in China. Since the beginning of this century, comprehensive measures have been taken to control the continuous aggravation of large land subsidence patterns in some areas; however, urban land subsidence issues, influenced by various factors, still persist and exhibit complex geographical distribution characteristics. In this study, we utilized Sentinel-1A images and the SBAS-InSAR technique to capture surface deformation over the HJH Plain in Zhejiang from 16 March 2017 to 20 January 2023. Through a comparative analysis with geological conditions, changes in surface mass loading, rainfall and groundwater, and land use types, we discussed the contributions of natural and anthropogenic factors to land subsidence. Augmented with optical remote sensing images and field investigations, we conducted a correlation analysis of the land subsidence status. The preliminary findings suggest that changes in surface mass loading and short-term heavy rainfall under extreme weather conditions can lead to periodic land subsidence changes in the region. Additionally, extensive infrastructure construction triggered by urbanization has resulted in significant and sustained land subsidence deformation. The research findings play an important guiding role in formulating scientifically effective strategies for land subsidence prevention and control, as well as urban planning and construction.

Abstract A devastating doublet of earthquakes with moment magnitude MW 7.9 and MW 7.6 earthquakes contiguously occurred in SE Türkiye near the NW border of Syria. Here we perform a potency‐density tensor inversion to simultaneously estimate rupture evolution and fault geometry for the doublet. We find the initial MW 7.9 earthquake involved discrete episodes of supershear rupture and back‐rupture propagation, and was triggered by initial rupture along a bifurcated splay of the East Anatolian Fault. The second MW 7.6 event was triggered by the earlier MW 7.9 event, and it involved more extensive supershear rupture along a favorably curved fault, and was likely stopped by geometric barriers at the fault ends. Our results highlight the multi‐scale cascading rupture growth across the complex fault network that affects the diverse rupture geometries of the 2023 Türkiye earthquake doublet, contributing to the strong ground shaking and associated devastation.

Three machine learning models are used to perform jet origin classification. These models are optimized for deployment on a field-programmable gate array device. In this context, we demonstrate how latency and resource consumption scale with the input size and choice of algorithm. Moreover, the models proposed here are designed to work on the type of data and under the foreseen conditions at the CERN large hadron collider during its high-luminosity phase. Through quantization-aware training and efficient synthetization for a specific field programmable gate array, we show that $\mathcal{O}(100)$ ns inference of complex architectures such as Deep Sets and Interaction Networks is feasible at a relatively low computational resource cost.

Abstract Earthquakes rarely occur in isolation but rather as complex sequences of fore, main and aftershocks. Assessing the associated seismic hazard requires a holistic view of event interactions. We conduct frictional sliding experiments on faulted Westerly Granite samples at mid‐crustal stresses to investigate fault damage and roughness effects on aftershock generation. Abrupt laboratory fault slip is followed by periods of extended stress relaxation and aftershocks. Large roughness promotes less co‐seismic slip and high aftershock activity whereas smooth faults promote high co‐seismic slip with few aftershocks. Conditions close to slip instability generate lab‐quake sequences that exhibit similar statistical distributions to natural earthquakes. Aftershock productivity in the lab is linearly related to the residual strain energy on the fault which, in turn, is controlled by the level of surface heterogeneity. We conclude that roughness and damage govern slip stability and seismic energy partitioning between fore, main and aftershocks in lab and nature.

Modern microscopy relies increasingly on microscope automation to improve throughput, ensure reproducibility or observe rare events. Automation requires computer control of the important elements of the microscope. Furthermore, optical elements that are usually fixed or manually movable can be placed on electronically-controllable elements. In most cases, a central electronics board is necessary to generate the control signals they require and to communicate with the computer. For such tasks, Arduino microcontrollers are widely used due to their low cost and programming entry barrier. However, they are limiting in their performance for applications that require high-speed or multiple parallel processes. Field programmable gate arrays (FPGA) are the perfect technology for high-speed microscope control, as they are capable of processing signals in parallel and with high temporal precision. While plummeting prices made the technology available to consumers, a major hurdle remaining is the complex languages used to configure them. In this work, we used an affordable FPGA, delivered with an open-source and friendly-to-use programming language, to create a versatile microscope control platform called MicroFPGA. It is capable of synchronously triggering cameras and multiple lasers following complex patterns, as well as generating various signals used to control microscope elements such as filter wheels, servomotor stages, flip-mirrors, laser power or acousto-optic modulators. MicroFPGA is open-source and we provide online Micro-Manager, Java, Python and LabVIEW libraries, together with blueprints and tutorials.

Abstract Earthquake swarms exhibit highly uncertain temporal behavior. We investigated the relationship between the swarm duration and the diffusivity of hypocenter migration for triggered earthquake swarms in northeastern Japan. These parameters were systematically estimated by applying a diffusion model and using a unified definition of time windows for the initial and final stages of swarm activity. This approach detected a clear negative correlation between the diffusivity and swarm durations. The relation follows a power-law with an exponent of $$-\,0.5$$ - 0.5 to $$-\,1.0$$ - 1.0 . Examination of published data confirmed that this relationship globally holds under various localities and tectonic environments. These results suggest that diffusivity, and by extension, crustal permeability and fluid viscosity play a key role in controlling the duration of the fluid-driven swarms.

The tidal triggering of earthquakes refers to the phenomenon that the stress change caused by the tide triggers the earthquake. Because the study of the tidal triggering of earthquakes may provide valuable information on the conditions of fault rupture, it has attracted the persistent attention of researchers around the whole world. In this paper, the related research methods and results are briefly reviewed. In the early days, investigation on seismic tidal triggering focus mainly on finding tidal period in seismic activity. As the research goes further, the correlation between seismic activity and tides is tested strictly by statistical test method. Up to now, whether earthquakes are triggered by tides or not is still unanswered. However, some researches show that seismic activity in the focal area is often triggered by tides in several years before a strong earthquake. If it is confirmed, new clues will be provided for earthquake prediction.

Induced seismicity has become a concern for industry and nearby residents. Fluid-induced earthquakes are a side effect of industrial operations such as hydraulic fracturing, where high-pressure fluids are pumped into the Earth’s crust to increase hydrocarbon flow to a well from petroleum-bearing rock formations. Previous studies on fluid-induced seismicity showed the existence of spatiotemporal clustering and aftershock activity. Here, we study seismic catalogs from the Kiskatinaw Seismic Monitoring and Mitigation Area (KSMMA), British Columbia, Canada to investigate spatiotemporal clustering and determine the aftershock activity due to secondary triggering mechanisms such as static and dynamic stress changes arising from preceding seismic events. Our analysis is based on modern tools of statistical seismology such as the Bi-test and triggering analysis. We find significant aftershock triggering and spatiotemporal clustering across the KSMMA but with large spatial variations, which might be indicative of pre-existing stresses and fault systems. In particular, aftershock triggering is characterized by rapidly decaying spatial distributions of aftershocks beyond the mainshock rupture area and by a strong dominance of small but frequent triggers, consistent with that observed for hydraulic fracturing and saltwater disposal elsewhere.

The purpose of the research is to identify biomechanical predictors that distinguish between high and low score athletes in biathlon shooting and to determine the relationships among these variables in field testing. Ten biathletes (3 female, 7 male) from CSS Dinamo Râșnov each fired 3 clips of 5 shots in prone and standing shooting positions without physical load, followed by 2 respective series in both disciplines during a simulated 12.5-km pursuit race on roller skis. Referring to the current results, athletes are recommended to focus on vertical rifle sway in prone position and on body sway across the shooting line during standing shooting when fatigued.

Background:The potential association of serum progesterone on the day of human chorionic gonadotropin administration with the outcome of intracytoplasmic sperm injection [ICSI] cycles has been one of the major controversies in the endocrinology of ovarian stimulation. Aim of the work: This study was conducted to estimate the net effect of progesterone elevation on the day of human chorionic gonadotrophin [hCG] on pregnancy outcome in women undergoing fresh embryo transfer in control ovarian stimulation using long agonist and antagonist protocols. Patients and Methods:This is a prospective study included a total of 177 patients who were indicated for ICSI. The included cases were divided into three groups according to progesterone level at the day of hCG. Both progesterone and E2 were estimated at the day of triggering. Results:Serum progesterone levels did not differ between cases who got pregnancy and who did not (p=0.435). Estrogen/Progesterone ratio was not significantly different between pregnant and non-pregnant females (p= 0.842). Conclusion: Progesterone level on the day of hCG administration does not have any effect on ICSI outcome.

Abstract Background The majority of stress-sensitive genes responds to cold and high light in the same direction, if plants face the stresses for the first time. As shown recently for a small selection of genes of the core environmental stress response cluster, pre-treatment of Arabidopsis thaliana with a 24 h long 4 °C cold stimulus modifies cold regulation of gene expression for up to a week at 20 °C, although the primary cold effects are reverted within the first 24 h. Such memory-based regulation is called priming. Here, we analyse the effect of 24 h cold priming on cold regulation of gene expression on a transcriptome-wide scale and investigate if and how cold priming affects light regulation of gene expression. Results Cold-priming affected cold and excess light regulation of a small subset of genes. In contrast to the strong gene co-regulation observed upon cold and light stress in non-primed plants, most priming-sensitive genes were regulated in a stressor-specific manner in cold-primed plant. Furthermore, almost as much genes were inversely regulated as co-regulated by a 24 h long 4 °C cold treatment and exposure to heat-filtered high light (800 μmol quanta m− 2 s− 1). Gene ontology enrichment analysis revealed that cold priming preferentially supports expression of genes involved in the defence against plant pathogens upon cold triggering. The regulation took place on the cost of the expression of genes involved in growth regulation and transport. On the contrary, cold priming resulted in stronger expression of genes regulating metabolism and development and weaker expression of defence genes in response to high light triggering. qPCR with independently cultivated and treated replicates confirmed the trends observed in the RNASeq guide experiment. Conclusion A 24 h long priming cold stimulus activates a several days lasting stress memory that controls cold and light regulation of gene expression and adjusts growth and defence regulation in a stressor-specific manner.

While triggering oocyte maturation with GnRH agonist (GnRHa) seems to be safe and effective in terms of the risk of developing OHSS and the number of metaphase II oocytes, it nevertheless results in luteal phase deficiency. To date, strategies have been developed in order to rescue defective luteal phase of GnRHa triggered cycles. Our study aimed to assess the reproductive outcome of GnRHa triggered cycles combined with modified luteal support (1500 IU hCG at the day of oocyte retrieval) in women with high ovarian response and to compare the outcome with hCG triggered cycles in GnRH antagonist IVF-ICSI procedures. A retrospective cohort database review of the results of GnRH antagonist IVF-ICSI cycles was conducted at a tertiary-care IVF center in Ljubljana, Slovenia. A total of 6126 cycles, performed from January 1, 2014, to December 31, 2020, were included in the final analysis. Final oocyte maturation was performed with either 5000, 6500, or 10,000 IU hCG (women with normal ovarian response) or 0.6 mg GnRHa (buserelin), supplemented with 1500 IU hCG on the day of oocyte retrieval (in women with high ovarian response). In cases of excessive ovarian response and/or high risk of OHSS luteal support was not introduced and all good quality blastocysts were frozen. According to significant differences in patients’ age and the number of oocytes in the two groups, matching by age and number of oocytes was performed. No significant differences were observed regarding pregnancy rate per embryo transfer, rate of early pregnancy loss, and livebirth rate per pregnancy between the GnRHa and hCG trigger groups, respectively. A significant difference in the number of developed embryos and blastocysts, as well as the number of frozen blastocysts, was seen in favor of the GnRHa trigger. However, the birth weight in the GnRHa trigger group was significantly lower.ConclusionThe results of our study support the use of GnRHa for final oocyte maturation in GnRH antagonist IVF cycles in women with high ovarian response. Luteal phase rescue was performed by co-administration of 1500 IU hCG on the day of oocyte retrieval and estradiol and progesterone supplementation. In our experience, such an approach results in a comparable reproductive outcome with hCG trigger group.

A high-quality, low-cost ventilator, dubbed HEV, has been developed by the particle physics community working together with biomedical engineers and physicians around the world. The HEV design is suitable for use both in and out of hospital intensive care units, provides a variety of modes and is capable of supporting spontaneous breathing and supplying oxygen-enriched air. An external air supply can be combined with the unit for use in situations where compressed air is not readily available. HEV supports remote training and post market surveillance via a Web interface and data logging to complement standard touch screen operation, making it suitable for a wide range of geographical deployment. The HEV design places emphasis on the ventilation performance, especially the quality and accuracy of the pressure curves, reactivity of the trigger, measurement of delivered volume and control of oxygen mixing, delivering a global performance which will be applicable to ventilator needs beyond the COVID-19 pandemic. This article describes the conceptual design and presents the prototype units together with a performance evaluation.

Ultrasound (US)-triggered nicotine release system in a cellulose hydrogel drug carrier was developed with three different cellulose concentrations of 0.45 wt%, 0.9 wt%, and 1.8 wt%. The nicotine-loaded cellulose hydrogels were fabricated by the phase inversion method when the nicotine and cellulose mixture in the 6 wt% LiCl/N, N-dimethylacetamide solvent was exposed to water vapor at room temperature. Nicotine was used as the medicine due to its revealed therapeutic potential for neurodegenerative diseases like Alzheimer's and Parkinson's diseases. The behavior of US-triggered nicotine release from nicotine-cellulose hydrogel was studied at 43 kHz US frequency at the changing US output powers of 0 W, 5 W, 10 W, 20 W, 30 W, and 40 W. The significant US-triggered nicotine release enhancement was noted for the hydrogels made with 0.9 wt% and 1.8 wt% cellulose loading. The matrix made with 0.9 wt% cellulose was exhibited the highest nicotine release at the 40 W US power, and differences in nicotine release at different US powers were noticeable than at 0.45 wt% and 1.8 wt% cellulose loadings. For the three cellulose hydrogel systems, the storage modulus (G′) values at the 0.01 wt% strain rate were dropped from their initial values due to the US irradiation. This reduction was proportionately decreased when the US power was increased. The deconvolution of FTIR spectra of nicotine-loaded cellulose films before and after US exposure was suggested breakage of cellulose-nicotine and cellulose-water in the matrix; thus, the stimulated nicotine release from the cellulose matrix was promoted by the US irradiation.

Dynamical systems theory has been often employed to study nonlinear flow and flame dynamics in combustion systems. However, the corresponding studies using nonlinear dynamics to analyze the Rijke tube thermoacoustic system are still occasional. Little study has been performed to elucidate the characteristics of triggering phenomenon in the bistable region of the thermoacoustic system. In this regard, the main objectives of the present research are to contribute analysis for the lack of literature in these areas, especially to study the bistability and triggering properties of a thermoacoustic system. The thermoacoustic model of a horizontal Rijke tube is firstly established. The governing equations are expanded and solved by using Galerkin method. The analysis of the system is carried out by using nonlinear dynamics theory. Linear and nonlinear stability boundaries for the variation of non-dimensional heater power, damping coefficient and the relative heater location are obtained for different values of non-dimensional time lag in the system. Regions of global stability, global instability and bistability are characterized. The bistable region in the relative heater location is distributed symmetrically with xf=0.25. It is observed that the bistable region in the relative heater location firstly decreases with an increase in the non-dimensional time lag, reaching a minimum value at a certain critical value of τ, then increases. The situation for the bistable region in the damping coefficient presents a reverse variation, And the bistable region reach the maximum at τ=0.5. The triggering phenomenon and limit cycle of the system in the bistable region are studied. The critical triggering values are determined with the changes of the non-dimensional heater power, the damping coefficient and the relative heater location. The critical triggering value of velocity perturbation decreases with the increase of non-dimensional heater power, whereas an increasing trend is observed with the increase of damping coefficient. Interestingly, the critical triggering value firstly decreases and then increases with the increase of the relative heater location. The variation of critical triggering value for pressure perturbation is found to correspond with velocity perturbation. In the bistable region, the amplitude and frequency of the steady limit cycle oscillation of the system are independent of the initial perturbation values, but the perturbation value has strong effect on the duration needed to achieve the steady limit cycle, and the time required for the system to reach the limit cycle under the perturbation of U1=0.4 is about 3 times longer than that of U1=0.8.

Rockfall is a frequent hazard in mountainous areas, but risks can be mitigated by the construction of protection structures and slope modification. In this study, two rock slopes along a highway in western Colorado were monitored monthly using Terrestrial Laser Scanning (TLS) before, during, and after mitigation activities were performed to observe the influence of construction and weather variables on rockfall activity. Between September 2020 and February 2021, the slopes were mechanically scaled and reinforced using rock bolts, wire mesh, and polyurethane resin injection. We used a state-of-the-art TLS monitoring workflow to process the acquired point clouds, including semi-automated algorithms for alignment, change detection, clustering, and rockfall-volume calculation. Our initial hypotheses were that the slope-construction activities would have an immediate effect on the rockfall rate post-construction and would exhibit a decreased correlation with weather-related triggering factors, such as precipitation and freeze-thaw cycles. However, our observations did not confirm this, and instead an increase in post-construction rockfall was recorded, with strong correlation to weather-related triggering factors. While this does not suggest that the overall mitigation efforts were ineffective in reducing rockfall hazard and risk of large blocks, we did not find evidence that mitigation efforts influenced the rockfall hazard associated with the release of small- to medium-sized blocks (3). These results can be used to develop improved and tailored mitigation methods for rock slopes in the future.

In the laser screen velocity measuring (LSVM) system, there is a deviation in the consistency of the optoelectronic response between the start light screen and the stop light screen. When the projectile passes through the light screen, the projectile’s over-target position, at which the timing pulse of the LSVM system is triggered, deviates from the actual position of the light screen (i.e., the target deviation). Therefore, it brings errors to the measurement of the projectile’s velocity, which has become a bottleneck, affecting the construction of a higher precision optoelectronic velocity measuring system. To solve this problem, this paper proposes a method based on high-speed shadow imaging to measure the projectile’s target deviation, ΔS, when the LSVM system triggers the timing pulse. The infrared pulse laser is collimated by the combination of the aspherical lens to form a parallel laser source that is used as the light source of the system. When the projectile passes through the light screen, the projectile’s over-target signal is processed by the specially designed trigger circuit. It uses the rising and falling edges of this signal to trigger the camera and pulsed laser source, respectively, to ensure that the projectile’s over-target image is adequately exposed. By capturing the images of the light screen of the LSVM system and the over-target projectile separately, this method of image edge detection was used to calculate the target deviation, and this value was used to correct the target distance of the LSVM to improve the accuracy of the measurement of the projectile’s velocity.

Earthquake is one of the dominant triggering factors of landslides. Given the wide areas covered by mega earthquake-triggered landslides, their inventory requires development of automatic or semi-automatic methods applied to satellite imagery. A detection method is here proposed for this purpose, to fit with simple datasets; SPOT5 panchromatic images of 5 m resolution coupled with a freely and globally available DEM. The method takes advantage of multi-temporal images to detect changes based on radiometric variations after precise coregistration/orthorectification. Removal of false alarms is then undertaken using shape, orientation and radiometric properties of connected pixels defining objects. 80% of the landslides and 93% of the landslide area are detected indicating small omission errors but 50% of false alarms remain. They are removed using expert based analysis of the inventory. The method is applied to realize the first comprehensive inventory of landslides triggered by the Pisco earthquake (Peru, 15/08/2007, Mw 8.0) over an area of 27,000 km2. 866 landslides larger than 100 m2 are detected covering a total area of 1.29 km2. The area/number distribution follows a power-law with an exponent of 1.63, showing a very particular regime of triggering in this arid environment compared to other areas in the world. This specific triggering can be explained by the little soil cover in the coastal and forearc regions of Peru. Analysis of this database finally shows a major control of the topography (both orientation and inclination) on the repartition of the Pisco-triggered landslides.

We analyzed the possibility of the two-step triggering of nuclear isomers by short X-ray laser pulses via an excited intermediate level. The estimations of the decay acceleration are performed for the 6− isomer of 84Rb in the field of future European X-ray laser.

Rainfall plays an important role in the landslide triggering processes. Analyses of landslide occurrence in the area of Slovenia have shown that areas where intensive rainstorms occure (maximal daily rainfall for the 100 years period), and where the geologicalsettings are favourable, abundance of landslide can be expected. This clearly indicates the spatial and temporal dependence of landslide occurrence upon the intensive rainfall. Regarding the landslide occurrence, the intensity of maximal daily and average annual rainfall for the the 30 years period were analysed. Results have shown that daily rainfall intensity, which significantly influences the triggering of landslides, ranges from 100 to 150 mm, most probably above 130 mm. Despite the vague influence, if any at all,of the average annual rainfall, the threshold above which significant number of landslides occurs is 1000 mm.

How does T cell receptor signaling begin? Answering this question requires an understanding of how the parts of the molecular machinery that mediates this process fit and work together. Ultimately this molecular architecture must (i) trigger the relay of information from the TCR-pMHC interface to the signaling substrates of the CD3 molecules and (ii) bring the kinases that modify these substrates in close proximity to interact, initiate, and sustain signaling. In this contribution we will discuss advances of the last decade that have increased our understanding of the complex machinery and interactions that underlie this type of signaling.