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An experimental observation has been made by using aluminum-coated Mylar foils, which strongly supports that in the case of plastic target, the energetic part of the proton beam originates from the front-side of the target. When a 30 fs laser pulse with an intensity of 1.6×1019 W/cm2 was irradiated on the 12.5-μm-thick Mylar side of the aluminum-coated Mylar foil, the maximum proton energy was reduced by a factor 5.5 as compared to that of 3.3 MeV observed from the single layer of the Mylar foil. With the help of a two-dimensional particle-in-cell simulation, these observations can be interpreted that in the case of plastic target, the energetic proton beam originates from the front-side of the target. In the case of an aluminum-coated 6-μm-thick Mylar foil, more energetic proton beams of 4.7 MeV were also observed when the laser pulse was irradiated on the aluminum side as compared to those of 3.4 MeV from the single Mylar foil. [ABSTRACT FROM AUTHOR]

Frontotemporal dementia (FTD) is a clinical syndrome characterized by progressive decline in social conduct and a focal pattern of frontal and temporal lobe damage. Its biological basis is still poorly understood but the focality of the brain degeneration provides a powerful model to study the cognitive and anatomical basis of social cognition. Here, we present Dr. A, a patient with a rare hereditary bone disease (hereditary multiple exostoses) and FTD (pathologically characterized as Pick's disease), who presented with a profound behavioral disturbance characterized by acquired sociopathy. We conducted a detailed genetic, pathological, neuroimaging and cognitive study, including a battery of tests designed to investigate Dr. A's abilities to understand emotional cues and to infer mental states and intentions to others (theory of mind). Dr. A's genetic profile suggests the possibility that a mutation causing hereditary multiple exostoses, Ext2, may play a role in the pattern of neurodegeneration in frontotemporal dementia since knockout mice deficient in the Ext gene family member, Ext1, show severe CNS defects including loss of olfactory bulbs and abnormally small cerebral cortex. Dr. A showed significant impairment in emotion comprehension, second order theory of mind, attribution of intentions, and empathy despite preserved general cognitive abilities. Voxel-based morphometry on structural MRI images showed significant atrophy in the medial and right orbital frontal and anterior temporal regions with sparing of dorsolateral frontal cortex. This case demonstrates that social and emotional dysfunction in FTD can be dissociated from preserved performance on classic executive functioning tasks. The specific pattern of anatomical damage shown by VBM emphasizes the importance of the network including the superior medial frontal gyrus as well as temporal polar areas, in regulation of social cognition and theory of mind. This case provides new evidence regarding the neural basis of social cognition and suggests a possible genetic link between bone disease and FTD. [ABSTRACT FROM AUTHOR]

The effect of a laser prepulse on the generation of proton beams is compared between plastic and metal targets by irradiating a 30 fs, 2.4×1018 W/cm2 Ti:sapphire laser pulse. Proton energies generated from both target materials increase as the pulse duration of the laser prepulse decreases. However, it was found that there are distinct differences with respect to target materials. In the case of aluminum targets, as target thickness decreases, proton energy gets higher, which is well described by an isothermal expansion model. However, in the case of Mylar® targets, no such dependence on target thickness could be observed, and the highest maximum proton energies are higher by factors of 1.5 to 3 than those from aluminum targets or those predicted by the isothermal expansion model. Such characteristics of the proton beams from Mylar® targets can be accounted for by a bulk acceleration model, or acceleration by a resistively induced electric field. [ABSTRACT FROM AUTHOR]

Soft x-ray spectra (40-180 Å) produced by the interaction of 25 fs laser pulses at an intensity of ∼7x10[sup 16] W/cm[sup 2] with a cryogenically cooled Ar gas jet have been measured. New spectral lines from Ar[sup 8+] and Ar[sup 9+] charge states appeared with decreasing gas temperature. Nonlinear increase of x-ray line emission from Ar[sup 7+], Ar[sup 8+], and Ar[sup 9+] was observed with cooling, which saturated below certain temperature. The drastic change in the spectrum is attributed to efficient collisional heating and collisional ionization of growing (10[sup 2]-10[sup 3] atoms) Ar clusters from the cooled jet. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Prior case reports have suggested that treating thoracic outlet syndrome (TOS) may relieve intractable migraine headaches, but there has been no case series large enough to show when underlying TOS should be suspected as a contributor to migraine burden. This observational followed by questionnaire study was performed in an outpatient neurology practice to identify clinical features of patients with migraine in which TOS contributed to migraine burden. We report the clinical features of 50 consecutive patients (48 women, 2 men, age = 43.9+/12.7 years) who were treated for chronic migraine and TOS (20 migraine with aura, 28 migraine without aura, two hemiplegic migraines). Headaches had become chronic within 1 year of onset in 21 patients (42%) with characteristics as follows (percentages are based on known data): greater severity ipsilateral to TOS limb pain (38/50=76%), presence of limb swelling (32/48=67%), and worsened by recumbency (32/38=84%). Thirty-two patients eventually needed surgery, which included percutaneous transluminal venoplasty, 1st rib removal, scalenectomy, pectoralis minor tenotomy, and/or vein patching. The mean improvement of headaches on the treated side was 72 ± 26.7%; 12 patients experienced complete resolution of headaches after treatment of TOS (follow-up 7.2 ± 5.2 months). Questionnaire responders reported significant reductions in headache days (18.3 ± 8.6 to 11.1 ± 10.8 days/month, p < 0.0016), severity (7.8+/2.5 to 5.4 ± 2.9, p < 0.00079), and need for emergency care (3.6 ± 4.0 to 0.71 ± 1.3 visits/year, p < 0.0029). Chronic migraines can be important manifestations of TOS. Early transition to a chronic state, lateralized limb pain, and headaches worsened by recumbency are clues to the contribution of TOS pathology. Addressing the TOS contribution to migraine can significantly reduce migraine headache burden., (© 2024 The Author(s). Clinical Anatomy published by Wiley Periodicals LLC on behalf of American Association of Clinical Anatomists and British Association of Clinical Anatomists.)

Ceramic bearings have several desirable properties, such as resistance to wear, hardness, and biocompatibility, that favour it as an articulating surface in hip arthroplasty. However, ceramic fracture remains a concern. We have reviewed the contemporary literature, addressing the factors that can influence the incidence of ceramic bearing surface fracture. Cite this article: Bone Joint J 2019;101-B:897-901.

Temporomandibular disorders are painful conditions that require precise injection therapy in selected patients. This pilot cadaveric study was undertaken to compare the accuracy of temporomandibular joint (TMJ) injection between the anatomical landmark-based (blind) technique and an ultrasound-guided technique. TMJ injections using the blind technique or the ultrasound-guided technique were performed in 10 non-embalmed cadavers. After dissection, the accuracy of the TMJ injections was found to be significantly greater for the ultrasound-guided injections than for the blind technique (blind 55% vs. ultrasound 95%, P=0.008). For injections into the upper joint space of the TMJ, the success rate of the injection was comparable for the two techniques (blind 80% vs. ultrasound 100%, P=0.474). However, ultrasound-guided injections into the lower joint space had a much higher success rate than the blind technique (blind 30% vs. ultrasound 90%, P=0.020). The blind technique was associated with a considerable proportion of failed or inappropriate injections, especially for lower joint space injections. Ultrasound-guided TMJ injections were accomplished with a higher accuracy than the conventional blind technique, especially in the case of injections targeting the lower joint space of the TMJ., (Copyright © 2018 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Proton beams generated from thin aluminum and Mylar foil targets that are irradiated by a 30fs Ti:sapphire laser pulse with an intensity of 2.2x10;{18}Wcm;{2} were investigated. Protons from the Mylar targets were observed to have an energy higher by a factor of 2 and were higher in number by an order of magnitude as compared with those generated from the aluminum targets. The maximum proton energy of 1.3+/-0.12MeV obtained from the Mylar target was found to be similar with previous observations that used laser pulses with different intensities. To address the anomalous behavior of the maximum proton energy for plastic targets, an acceleration model is proposed. In this model, the protons are accelerated by a resistively induced electric field in the front of the target, which can account for the experimental observations.

We have developed a silver-mirror-based multipass preamplifier for a broadband amplification in a terawatt Ti:sapphire laser. With the extremely broad bandwidth of the silver mirrors, a very broad amplified spectrum can be generated at an amplified energy of 4 mJ; the amplified spectral width is 65 nm at half maximum and 160 nm at -25 dB without any spectral shaping technique. Such a broad amplification can be explained well by the simulation that includes gain narrowing and gain saturation. Even after a further amplification to an energy of 600 mJ, the amplified spectrum is broad enough to support an approximately 20 fs transform-limited pulse duration.

Conclusion: Coexistent migraine affects relevant clinical features of patients with Ménière's disease (MD)., Objective: Epidemiological studies have shown an association between migraine and MD. We sought to determine whether the coexistence of migraine affects any clinical features in patients with MD., Patients and Methods: In this retrospective case-control study of University Neurotology Clinic patients, 50 patients meeting 1995 AAO-HNS criteria for definite MD were compared to 18 patients meeting the same criteria in addition to the 2004 IHS criteria for migraine (MMD). All had typical low frequency sensorineural hearing loss and episodes of rotational vertigo. Outcome measures included: sex, age of onset of episodic vertigo or fluctuating hearing loss, laterality of hearing loss, aural symptoms, caloric responses, severity of hearing loss, and family history of migraine, episodic vertigo or hearing loss., Results: Age of onset of episodic vertigo or fluctuating hearing loss was significantly lower in patients with MMD (mean +/- 1.96*SE = 37.2 +/- 6.3 years) than in those with MD (mean +/- 1.96*SE = 49.3 +/- 4.4 years). Concurrent bilateral aural symptoms and hearing loss were seen in 56% of MMD and 4% of MD patients. A family history of episodic vertigo was seen in 39% of MMD and 2% of MD patients.

We studied a family with nonprogressive congenital ataxia (NPCA) previously reported in 1985. Follow-up evaluation documented a nonprogressive course. Older family members developed ataxic spells and vertical oscillopsia triggered by stress and exercise. Linkage analysis using a 10K single-nucleotide polymorphism array found suggestive linkage to four loci on chromosomes 1q44, 5q35.1-35.3, 7q36.2-36.3, and 9q31.2-32 and ruled out linkage to the NPCA locus on 3p, proving genetic heterogeneity for autosomal dominant NPCA.

Relativistic, nonlinear Thomson scattering by an electron of an intense laser field has been investigated by computer simulation. Under a laser field with a pulse duration of 20-fs full width at half maximum and an intensity of 10(20) W/cm(2), the motion of an electron is highly relativistic and generates an ultrashort radiation of 2 as with photon energies from 100 to 600 eV. An interesting modulated structure of the spectrum is observed and analyzed. A radiation produced by the zigzag motion of an electron under a linearly polarized laser has better characteristics than by a helical motion under a circularly polarized laser pulse in terms of an angular divergence and an energy spectrum. The effect of ion field in a plasma was also investigated, which shows that for a laser intensity of 10(20) W/cm(2), the ion field due to an ion density of up to 7 x 10(18) cm(-3) can be ignored during the laser pulse.

The title compound, crystallized with a few percent of deuterium, contains some NH(3)D(+) and HOD. At low temperatures, five N-D stretch bands are observed. These belong to two ammonium sites with apparent C(s) symmetry in the low-temperature phase. The N-D bands can be hole-burned with an infrared laser. Burning bands belonging to the A-sites transforms some of them to the higher-energy B-sites. The A- and B-sites probably differ from each other by the arrangement of water and sulfate about the ammonium.

In a 4-cell stage C. elegans embryo, signaling by the P2 blastomere induces anterior-posterior polarity in the adjacent EMS blastomere, leading to endoderm formation. We have taken genetic and reverse genetic approaches toward understanding the molecular basis for this induction. These studies have identified a set of genes with sequence similarity to genes that have been shown to be, or are implicated in, Wnt/Wingless signaling pathways in other systems. The C. elegans genes described here are related to wnt/wingless, porcupine, frizzled, beta-catenin/armadillo, and the human adenomatous polyposis coli gene, APC. We present evidence that there may be partially redundant inputs into endoderm specification and that a subset of these genes appear also to function in determining cytoskeletal polarity in certain early blastomeres.