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In many real-life applications, job processing times are a function of the waiting time prior to their execution. In the most general setting, each job comprises of a basic processing time, which is independent of its start time, and a start time-dependent deterioration function. Some common examples of deteriorating systems include fire fighting, pollution containment, and medical treatments. To date, research has focused on scheduling models where the basic processing time of jobs is constant. However, job processing times are often controllable through the allocation of a limited non-renewable resource. We study a single-machine setting that combines these two models under the assumptions of general linear deterioration and convex resource functions. We develop a polynomial time solution for minimizing the makespan. For the total flowtime criterion, we compute the optimal resource allocation policy for a given job instance and show that the sequencing problem is at least as hard as the case with non-controllable jobs. We follow by discussing the properties of several special cases.

A key challenge in attosecond science is the temporal characterization of attosecond pulses that are essential for understanding the evolution of electronic wavefunctions in atoms, molecules and solids1–7. Current characterization methods, based on nonlinear light–matter interactions, are limited in terms of stability and waveform complexity. Here, we experimentally demonstrate a conceptually new linear and all-optical pulse characterization method, inspired by double-blind holography. Holography is realized by measuring the extreme ultraviolet (XUV) spectra of two unknown attosecond signals and their interference. Assuming a finite pulse duration constraint, we reconstruct the missing spectral phases and characterize the unknown signals in both isolated pulse and double pulse scenarios. This method can be implemented in a wide range of experimental realizations, enabling the study of complex electron dynamics via a single-shot and linear measurement.Double-blind holography allows reconstruction of the missing spectral phases and characterization of the unknown signals in both isolated-pulse and double-pulse scenarios, facilitating the study of complex electron dynamics via a single-shot and linear measurement.

We study the optimality of the very practical policy of equal allocation of jobs to batches in batch scheduling problems on an m-machine open shop. The objective is minimum makespan. We assume unit processing time jobs, machine-dependent setup times and batch availability. We show that equal allocation is optimal for a two-machine and a three-machine open shop. Although, this policy is not necessarily optimal for larger size open shops, it is shown numerically to produce very close-to-optimal schedules.

Molecular vibrations have oscillation periods that reflect the molecular structure, and are hence being used as a spectroscopic fingerprint for detection and identification. At present, all nonlinear spectroscopy schemes use two or more laser beams to measure such vibrations. The availability of ultrashort (femtosecond) optical pulses with durations shorter than typical molecular vibration periods has enabled the coherent excitation of molecular vibrations using a single pulse. Here we perform single-pulse vibrational spectroscopy on several molecules in the liquid phase, where both the excitation and the readout processes are performed by the same pulse. The main difficulty with single-pulse spectroscopy is that all vibrational levels with energies within the pulse bandwidth are excited. We achieve high spectral resolution, nearly two orders of magnitude better than the pulse bandwidth, by using quantum coherent control techniques. By appropriately modulating the spectral phase of the pulse we are able to exploit the quantum interference between multiple paths to selectively populate a given vibrational level, and to probe this population using the same pulse. This scheme, using a single broadband laser source, is particularly attractive for nonlinear microscopy applications, as we demonstrate by constructing a coherent anti-Stokes Raman (CARS) microscope operating with a single laser beam.

The three-dimensional (3D) turbulent mixing zone (TMZ) evolution under Rayleigh–Taylor and Richtmyer–Meshkov conditions was studied using two approaches. First, an extensive numerical study was made, investigating the growth of a random 3D perturbation in a wide range of density ratios. Following that, a new 3D statistical model was developed, similar to the previously developed two-dimensional (2D) statistical model, assuming binary interactions between bubbles that are growing at a 3D asymptotic velocity. Confirmation of the theoretical model was gained by detailed comparison of the bubble size distribution to the numerical simulations, enabled by a new analysis scheme that was applied to the 3D simulations. In addition, the results for the growth rate of the 3D bubble front obtained from the theoretical model show very good agreement with both the experimental and the 3D simulation results. A simple 3D drag–buoyancy model is also presented and compared with the results of the simulations and the experiments with good agreement. Its extension to the spike-front evolution, made by assuming the spikes' motion is governed by the single-mode evolution determined by the dominant bubbles, is in good agreement with the experiments and the 3D simulations. The good agreement between the 3D theoretical models, the 3D numerical simulations, and the experimental results, together with the clear differences between the 2D and the 3D results, suggest that the discrepancies between the experiments and the previously developed models are due to geometrical effects.

The present article describes an experimental study that is a part of an integrated theoretical (Rikanati et al. 2003) and experiential investigation of the Richtmyer–Meshkov (RM) hydrodynamic instability that develops on a perturbed contact surface by a shock wave. The Mach number and the high initial-amplitude effects on the evolution of the single-mode shock-wave-induced instability were studied. To distinguish between the above-mentioned effects, two sets of shock-tube experiments were conducted: high initial amplitudes with a low-Mach incident shock and small amplitude initial conditions with a moderate-Mach incident shock. In the high-amplitude experiments a reduction of the initial velocity with respect to the linear prediction was measured. The results were compared to those predicted by a vorticity deposition model and to previous experiments with moderate and high Mach numbers done by others and good agreement was found. The result suggested that the high initial-amplitude effect is the dominant one rather than the high Mach number effect as suggested by others. In the small amplitude–moderate Mach numbers experiments, a reduction from the impulsive theory was noted at late stages. It is concluded that while high Mach number effect can dramatically change the behavior of the flow at all stages, the high initial-amplitude effect is of minor importance at the late stages. That result is supported by a two-dimensional numerical simulation.

The late-time growth rate of the Richtmyer–Meshkov instability was experimentally studied at different Atwood numbers with two-dimensional (2D) and three-dimensional (3D) single-mode initial perturbations. The results of these experiments were found to be in good agreement with the results of the theoretical model and numerical simulations. In another set of experiments a bubble-competition phenomenon, which was observed in previous work for 2D initial perturbation (Sadot et al., 1998), was shown to exist also when the initial perturbation is of a 3D nature.

The ultrasound-guided superficial cervical plexus (SCP) block may be useful for providers in emergency care settings who care for patients with injuries to the ear, neck, and clavicular region, including clavicle fractures and acromioclavicular dislocations. The SCP originates from the anterior rami of the C1-C4 spinal nerves and gives rise to 4 terminal branches—greater auricular, lesser occipital, transverse cervical, and suprascapular nerves—that provide sensory innervation to the skin and superficial structures of the anterolateral neck and sections of the ear and shoulder. Here we describe an ultrasound-guided technique for blockade of the SCP that is potentially well suited to emergency care settings. We present the first case description of its successful use to manage pain for a patient with an acute clavicle fracture. This case is presented to highlight one of several potential applications of this promising new technique in the emergency department.

In January 2014, a mass protest of 40,000 African migrants, demanding rights, recognition and a fair asylum process took place in Tel-Aviv. Their demonstration was unprecedented in its nature and magnitude offering a unique and interesting puzzle: how a foreign-born community without resources or familiarity with the country’s authorities, culture, or tolerance for protest, successfully mobilized and why did the high cost of engaging in protest did not deter the participants? Exiting literature often treats mobilization as an engagement with traditional political institutions, those however, are mostly irrelevant for people without legal status. Scholarship on the issue tends to separate the analysis of the macro level (structure and institutions) from that of the micro level (identity and culture). This gap creates a disconnect between the structural conditions and the ways in which they are experienced and understood at the individual and community levels. My hypothesis is that mass organizing by irregular migrants is dependent on their ability to draw on their lived experiences and skill-sets to navigate an alien political structure and utilize the support of local allies to make legal claims and political demands. To test it, I used a mixed methods approach combining content analysis of articles and reports with fieldwork conducted in Israel in 2016–17 featuring interviews with asylum seekers, activists and NGO workers. The case of asylum seekers in Israel demonstrates their ability to self-organize as a diasporic group with collective interests as well the cooperation they built with local human-rights NGOs and other aid groups as the basis for their successful collective operation. Their struggle raised important questions about Israel’s migration regime, workforce dependability, and the balance between adherence to democratic norms and securing a Jewish majority, while capturing the attention of global media and international actors. Despite the inability to achieve their stated policy goals, their success is articulated by their own admission in their ability to mobilize and spread the language of rights in their communities. By examining the similarities in collective action practices and discourses adopted by migrant movements in Washington State I discuss the struggle of asylum seekers in Israel in a wider context and offer a comparative perspective on social movements and political engagement of unrecognized members of society.

•Describes a connection between stimulant drug abuse and Takotsubo cardiomyopathy•Identifies the utility of bedside ultrasound in identifying the classic features of Takotsubo cardiomyopathy•Includes still images, EKG, ventriculogram, and supplementary movies of the dysfunctional left ventricle