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Background: Extensor pollicis longus (EPL) rupture and tenosynovitis of the third dorsal compartment is often described in association with a history of rheumatoid arthritis or in the setting of a distal radius fracture. However, the literature suggests multiple other potential factors that may lead to a seemingly spontaneous rupture., Methods: We performed a systematic review following guidelines set forth by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The search consisted of headings and keywords related to tendon injuries, tendinopathy, hand surgery, tendon transfer, and injections, as published in reports and studies. Citations were screened by title and abstract against predetermined inclusion and exclusion criteria by 2 independent reviewers, with a third reviewer resolving discrepancies. To be eligible, articles had to meet the following inclusion criterion: describe cases of spontaneous EPL rupture or tenosynovitis of the third dorsal compartment. The exclusion criterion was any history of distal radius fracture or rheumatoid arthritis., Results: We identified 29 articles that met the inclusion criterion., Conclusions: A myriad of prodromal events or predisposing factors ultimately led to EPL rupture or tenosynovitis of the third compartment. Methods of reconstruction described included primary repair, tendon grafting, and tendon transfer techniques; all with generally good outcomes. These results highlight the inherent fragility of this tendon and support the historical recommendation for early release of the EPL tendon in the setting of tenosynovitis of the third dorsal compartment., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

We use photoluminescence (PL) imaging to study damage growth precursors within laser damage sites on the surface of silica. Damage site evolution is induced by multiple shots of UV nanosecond pulsed laser at various energy densities and monitored throughout the early stages of growth. Wide-field PL imaging rapidly locates microscopic light absorption centers within the silica damage site. Our quantitative analysis shows that damage sites with strong local PL intensity show a higher probability of growth upon subsequent laser pulses. Scanning electron microscopy (SEM) paired with a study of PL spectrum shows that the strong PL intensity appears from the subsurface fractures with high defect density, which provides a local light absorption center leading to significant damage growth. We believe that this result offers an efficient optical damage mitigation strategy by providing a rapid and non-destructive optical inspection approach.

Structured conical blockers manufactured on optical input surfaces are being used to shadow, and thereby, arrest growth of exit surface damage on large optics for applications in high-energy laser systems to extend their lifetime usage. However, as the size of the Shadow Cone Blocker (SCB) is increased, the deflected light must be carefully managed to prevent consequential damage from downstream intensification. Here, we design and fabricate a distinct input SCB geometry to alleviate this problem, enabling larger damage site mitigation. The demonstrated ∼1 mm diameter SCB was manufactured with a convergent approach using a CO 2 pulsed laser ablative scanning sequence on a fused silica window. The SCB design was refined to maximize resistance to both input and exit surface damage initiations on 1 cm thick fused silica windows when exposed to 351 nm irradiation and validated with laser damage testing. The design showed to prevent damage onset to the exit surface for incident fluences on the SCB of 10.7 ± 1.3  J·cm -2 and is resistant to damage on the input surface exceeding 30 J·cm -2 input fluence.

To fabricate optical components with surface layers compatible with high-power laser applications that may operate as antireflective coatings, polarization rotators, or harness physical anisotropy for other uses, metasurfaces are becoming an appealing candidate. In this study, large-beam (1.05 cm diameter) 351-nm laser-induced damage testing was performed on an all-glass metasurface structure composed of cone-like features with a subwavelength spacing of adjacent features. These structures were fabricated on untreated fused silica glass and damage tested, as were structures that were fabricated on fused silica glass that experienced a preliminary etching process to remove the surface Beilby layer that is characteristic of polished fused silica. The laser-induced damage onset for structures on untreated fused silica glass was 19.3 J ⋅ c m -2 , while the sample that saw an initial pretreatment etch exhibited an improved damage onset of 20.4 J ⋅ c m -2 , only 6% short of the reference pretreated glass damage onset of 21.7 J ⋅ c m -2 . For perspective, the National Ignition Facility operational average fluence at this wavelength and pulse length is about 10 J / c m 2 . At a fluence of 25.5 J ⋅ c m -2 , the reference (pretreated) fused silica initiated 5.2 damage sites per m m 2 , while the antireflective metasurface sample with a preliminary etching process treatment initiated 9.8 damage sites per m m 2 . These findings demonstrate that substrate-engraved metasurfaces are compatible with high energy and power laser applications, further broadening their application space.

We describe a wide-field approach to probe transient changes in photoluminescence (PL) of defects on silica surfaces. This technique allows simultaneous capture of spatially resolved PL with spontaneous quenching behavior. We attribute the quenching of PL intensity to photochemical reactions of surface defects and/or subsurface fractures with ambient molecules. Such quenching curves can be accurately reproduced by our theoretical model using two quenchable defect populations with different reaction rates. The fitting parameters of our model are spatially correlated to fractures in silica where point defects and mechanical stresses are known to be present, potentially indicating regions prone to laser-induced damage growth. We believe that our approach allows rapid spatial resolved identification of damage prone morphology, providing a new pathway to fast, non-destructive predictions of laser-induced damage growth.

Management and control of damage initiation and growth on high-value National Ignition Facility (NIF) optics are critical to its operation. Cone-shaped features are currently being used on the input surfaces to arrest growth of exit surface damage by creating "shadows." Light refracted from the walls of the cones interferes with the incident beam at the exit surface to create an intensified annulus. Significant exit surface damage was observed at the locations of these annuli. Analysis showed that this damage is consistent with a recently reported new mechanism that degrades damage resistance by dispersing damage precursors over the surface upon exposure to UV laser radiation. This has significant implications for the design and operation of high-energy and power laser systems such as the NIF.

Background: Individuals with hypertrophic cardiomyopathy (HCM), even when asymptomatic, are at-risk for sudden cardiac death and stroke from arrhythmias, making it imperative to identify individuals affected by this familial disorder. Consensus guidelines recommend that first-degree relatives (FDRs) of a person with HCM undergo serial cardiovascular evaluations., Methods: We determined the uptake of family screening in patients with HCM and developed an online video intervention to facilitate family communication and screening. Family screening and genetic testing data were collected through a prospective quality improvement initiative, a standardized clinical assessment and management plan (SCAMP), utilized in an established cardiovascular genetics clinic. Patients were prescribed an online video if screening of their FDRs was incomplete and a pilot study on video utilization and family communication was conducted., Results: Two-hundred and sixteen probands with HCM were enrolled in SCAMP Phase I and 190 were enrolled in SCAMP Phase II. In both phases, probands reported that 51% of FDRs had been screened (382/749 in Phase I, 258/504 in Phase II). Twenty patients participated in a pilot study on video utilization and family communication. Nine participants reported watching the video and six participants reported sharing the video with relatives; however only one participant reported sharing the video with relatives who were not yet aware of the diagnosis of HCM in the family., Conclusion: Despite care in a specialized cardiovascular genetics clinic, approximately one half of FDRs of patients with HCM remained unscreened. Online interventions and videos may serve as supplemental tools for patients communicating genetic risk information to relatives., (© 2019 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.)

The propagation of 355-nm, nanosecond pulses in absorbing glasses is investigated for the specific case examples of the broadband absorbing glass SuperGrey and the Ce 3+ -doped silica glass. The study involves different laser irradiation conditions and material characterization methods to capture the transient material behaviors leading to laser-induced damage. Two damage-initiation mechanisms were identified: (1) melting of the surface as a result of increased temperature; and (2) self-focusing caused by a transient change in the index of refraction. Population of excited states greatly affects both mechanisms by increasing the transient absorption cross section via excited-state absorption and introducing a change of the refractive index to support the formation of graded-index lensing and self-focusing of the beam inside the material. The governing damage-initiation mechanism depends on the thermodynamic properties of the host glass, the electronic structure characteristics of the doped ion, and the laser-spot size.

We demonstrate that fused-silica samples exposed to nanosecond laser pulses at 355 nm and 1064 nm develop long-lived electrostatic charges on their surfaces. These charges extend well beyond the area exposed to the laser beam. The results suggest this effect is dependent on laser fluence and wavelength. In addition, ejected particles generated during laser-induced breakdown are electrostatically charged. Experiments indicate that such electrostatic charges can produce forces that can support the transport of dielectric and metallic microspheres between surfaces. This in turn can promote increased contamination of optical components during operation at relevant excitation conditions.

We investigate the role of defects in laser-induced damage of fused silica and of silica coatings produced by e-beam and PIAD processes which are used in damage resistant, multi-layer dielectric, reflective optics. We perform experiments using 1053 nm, 1-60 ps laser pulses with varying beam size, number of shots, and pulse widths in order to understand the characteristics of defects leading to laser-induced damage. This pulse width range spans a transition in mechanisms from intrinsic material ablation for short pulses to defect-dominated damage for longer pulses. We show that for pulse widths as short as 10 ps, laser-induced damage properties of fused silica and silica films are dominated by isolated absorbers. The density of these precursors and their fluence dependence of damage initiation suggest a single photon process for initial energy absorption in these precursors. Higher density precursors that initiate close to the ablation threshold at shorter pulse widths are also observed in fused silica, whose fluence and pulse width scaling suggest a multiphoton initiation process. We also show that these initiated damage sites grow with subsequent laser pulses. We show that scaling laws obtained in more conventional ways depend on the beam size and on the definition of damage for ps pulses. For this reason, coupling scaling laws with the density of precursors are critical to understanding the damage limitations of optics in the ps regime.

Laser-induced damage with ps pulse widths straddles the transition from intrinsic, multi-photon ionization and avalanche ionization-based ablation with fs pulses to defect-dominated, thermal-based damage with ns pulses. We investigated the morphology of damage for fused silica and silica coatings between 1 ps and 60 ps at 1053 nm. Using calibrated laser-induced damage experiments, in situ imaging, and high-resolution optical microscopy, atomic force microscopy, and scanning electron microscopy, we show that defects play an important role in laser-induced damage down to 1 ps. Three types of damage are observed: ablation craters, ultra-high density pits, and smooth, circular depressions with central pits. For 10 ps and longer, the smooth, circular depressions limit the damage performance of fused silica and silica coatings. The observed high-density pits and material removal down to 3 ps indicate that variations in surface properties limit the laser-induced damage onset to a greater extent than expected below 60 ps. Below 3 ps, damage craters are smoother although there is still evidence as seen by AFM of inhomogeneous laser-induced damage response very near the damage onset. These results show that modeling the damage onset only as a function of pulse width does not capture the convoluted processes leading to laser induced damage with ps pulses. It is necessary to account for the effects of defects on the processes leading to laser-induced damage. The effects of isolated defects or inhomogeneities are most pronounced above 3 ps but are still discernible and possibly important down to the shortest pulse width investigated here.

High energy laser systems are ultimately limited by laser-induced damage to their critical components. This is especially true of damage to critical fused silica optics, which grows rapidly upon exposure to additional laser pulses. Much progress has been made in eliminating damage precursors in as-processed fused silica optics (the advanced mitigation process, AMP3), and very high damage resistance has been demonstrated in laboratory studies. However, the full potential of these improvements has not yet been realized in actual laser systems. In this work, we explore the importance of additional damage sources-in particular, particle contamination-for fused silica optics fielded in a high-performance laser environment, the National Ignition Facility (NIF) laser system. We demonstrate that the most dangerous sources of particle contamination in a system-level environment are laser-driven particle sources. In the specific case of the NIF laser, we have identified the two important particle sources which account for nearly all the damage observed on AMP3 optics during full laser operation and present mitigations for these particle sources. Finally, with the elimination of these laser-driven particle sources, we demonstrate essentially damage free operation of AMP3 fused silica for ten large optics (a total of 12,000 cm 2 of beam area) for shots from 8.6 J/cm 2 to 9.5 J/cm 2 of 351 nm light (3 ns Gaussian pulse shapes). Potentially many other pulsed high energy laser systems have similar particle sources, and given the insight provided by this study, their identification and elimination should be possible. The mitigations demonstrated here are currently being employed for all large UV silica optics on the National Ignition Facility.

Objectives: Chest pain is a common complaint in the emergency department, and a small but important minority represents an acute coronary syndrome (ACS). Variation in diagnostic workup, risk stratification, and management may result in underuse, misuse, and/or overuse of resources., Methods: From July to October 2014, we conducted a prospective cohort study in an academic medical center by implementing a Standardized Clinical Assessment and Management Plan (SCAMP) for chest pain based on the HEART score. In addition to capturing adherence to the SCAMP algorithm and reasons for any deviations, we measured troponin sample timing; rates of stress test utilization; length of stay (LOS); and 30-day rates of revascularization, ACS, and death., Results: We identified 239 patients during the enrollment period who were eligible to enter the SCAMP, of whom 97 patients were entered into the pathway. Patients were risk stratified into one of 3 risk tiers: high (n = 3), intermediate (n = 40), and low (n = 54). Among low-risk patients, recommendations for troponin testing were not followed in 56%, and 11% received stress tests contrary to the SCAMP recommendation. None of the low-risk patients had elevated troponin measurements, and none had an abnormal stress test. Mean LOS in low-risk patients managed with discordant plans was 22:26 h/min, compared with 9:13 h/min in concordant patients (P < 0.001). Mean LOS in intermediate-risk patients with stress testing was 25:53 h/min, compared with 7:55 h/min for those without (P < 0.001). At 30 days, 10% of intermediate-risk patients and 0% of low-risk patients experienced an ACS event (risk difference 10% [0.7%-19%]); none experienced revascularization or death. The most frequently cited reason for deviation from the SCAMP was lack of confidence in the tool., Conclusions: Compliance with SCAMP recommendations for low- and intermediate-risk patients was poor, largely due to lack of confidence in the tool. However, in our study population, outcomes suggest that deviation from the SCAMP yielded no additional clinical benefit while significantly prolonging emergency department LOS.

Laser-induced Hertzian fractures on the exit surface of silica glass are found to result from metal surface-bound micro particles. Two types of metal micro-spheres are studied (stainless-steel and Al) using ultraviolet laser light. The fracture initiation probability curve as a function of fluence is obtained, resulting in an initiation threshold fluence of 11.1 ± 4.7 J/cm 2 and 16.5 ± 4.5 J/cm 2 for the SS and Al particles, accordingly. The modified damage density curve is calculated based on the fracture probability. The calculated momentum coupling coefficient linking incident laser fluence to the resulting plasma pressure is found to be similar for both particles: 32.6 ± 15.4 KN/J and 28.1 ± 10.4 KN/J for the SS and Al cases accordingly.

Precise assessment of the high fluence performance of pulse compressor gratings is necessary to determine the safe operational limits of short-pulse high energy lasers. We have measured the picosecond laser damage behavior of multilayer dielectric (MLD) diffraction gratings used in the compression of chirped pulses on the Advanced Radiographic Capability (ARC) kilojoule petawatt laser system at the Lawrence Livermore National Laboratory (LLNL). We present optical damage density measurements of MLD gratings using the raster scan method in order to estimate operational performance. We also report results of R-on-1 tests performed with varying pulse duration (1-30 ps) in air, and clean vacuum. Measurements were also performed in vacuum with controlled exposure to organic contamination to simulate the grating use environment. Results show sparse defects with lower damage resistance which were not detected by small-area damage test methods.

The burden of chronic pruritus is increasingly recognized as significant worldwide. As wet-laboratory researchers investigate the pathophysiology of chronic pruritus, epidemiologists and health services researchers are quantifying the impact of pruritus by incidence, prevalence, and quality of life measures. Outcomes researchers are also investigating factors that may predict chronic pruritus incidence and severity. Such efforts will direct resources for research, public health intervention, and clinical care.

Importance: Chronic pruritus is a common problem with a deleterious effect on quality of life. The factors mediating the relationship between chronic pruritus and quality of life are poorly understood., Objective: To determine the factors that mediate the impact of chronic pruritus on quality of life., Design, Setting, and Participants: Cross-sectional study based on a nationwide telephone survey of US military veterans sampled from the Veterans Hospital Patient Database. Participants were veterans who agreed to participate and were found to have chronic pruritus., Main Outcomes and Measures: Statistical significance of predictor variables (characteristics of patients and their chronic pruritus) in multivariate analysis using ItchyQoL scores as response variables., Results: Of 6000 veterans telephoned, 1075 consented to participate; 405 of these had chronic pruritus. Factors that mediated the impact of chronic pruritus on quality of life were demographic characteristics (age [P = .007], race [P = .05], marital status [P = .04]), personality (extroversion [P = .03], neuroticism [P = .01]), pruritus characteristics (severity [P < .001], duration [P = .01], frequency [P < .001], location [P = .005]), and possible etiology (cutaneous vs systemic [P = .03]). Notable factors not found significant include sex (P = .98) and socioeconomic variables (education level [P > .99], employment status [P = .53], income [P = .62])., Conclusions and Relevance: The multitude of factors that significantly influence the impact of chronic pruritus on quality of life demonstrates the complex nature of this relationship. A better appreciation of these factors will improve the clinical evaluation and treatment of chronic pruritus.

We present a comprehensive statistical model which includes both the probability of growth and growth rate to describe the evolution of exit surface damage sites on fused silica optics over multiple laser shots spanning a wide range of fluences. We focus primarily on the parameterization of growth rate distributions versus site size and laser fluence using Weibull statistics and show how this model is consistent with established fracture mechanics concepts describing brittle materials. Key growth behaviors and prediction errors associated with the present model are also discussed.

Surface damage is known to occur at fluences well below the intrinsic limit of the fused silica. A native surface precursor can absorb sub band-gap light and initiate a process which leads to catastrophic damage many micrometers deep with prominent fracture networks. Previously, the absorption front model of damage initiation has been proposed to explain how this nano-scale absorption can lead to macro-scale damage. However, model precursor systems designed to study initiation experimentally have not been able to clearly reproduce these damage events. In our study, we create artificial absorbers on fused silica substrates to investigate precursor properties critical for native surface damage initiation. Thin optically absorbing films of different materials were deposited on silica surfaces and then damage tested and characterized. We demonstrated that strong interfacial adhesion strength between absorbers and silica is crucial for the launch of an absorption front and subsequent damage initiation. Simulations using the absorption-front model are performed and agree qualitatively with experimental results.

Mutations in FOXP1, located at 3p13, have been reported in patients with global developmental delay (GDD), intellectual disability (ID), and speech defects. Mutations in FOXP2, located at 7q31, are well known to cause developmental speech and language disorders, particularly developmental verbal dyspraxia (DVD). FOXP2 has been shown to work co-operatively with FOXP1 in mouse development. An overlap in FOXP1 and FOXP2 expression, both in the songbird and human fetal brain, has suggested that FOXP1 may also have a role in speech and language disorders. We report on a male child with a 0.19 MB intragenic deletion that is predicted to result in haploinsufficiency of FOXP1. Review of our patient and others reported in the literature reveals an emerging phenotype of GDD/ID with moderate to severe speech delay where expressive speech is most severely affected. DVD appears not to be a distinct feature in this group. Facial features include a broad forehead, downslanting palpebral fissures, a short nose with broad tip, relative or true macrocephaly, a frontal hair upsweep and prominent digit pads. Autistic traits and other behavioral problems are likely to be associated with haploinsufficiency of FOXP1. Congenital malformations may be associated., (© 2013 Wiley Periodicals, Inc.)

Empirical numerical descriptions of the growth of laser-induced damage have been previously developed. In this work, Monte-Carlo techniques use these descriptions to model the evolution of a population of damage sites. The accuracy of the model is compared against laser damage growth observations. In addition, a machine learning (classification) technique independently predicts site evolution from patterns extracted directly from the data. The results show that both the Monte-Carlo simulation and machine learning classification algorithm can accurately reproduce the growth of a population of damage sites for at least 10 shots, which is extremely valuable for modeling optics lifetime in operating high-energy laser systems. Furthermore, we have also found that machine learning can be used as an important tool to explore and increase our understanding of the growth process.

Growth of laser damage on fused silica optical components depends on several key parameters including laser fluence, wavelength, pulse duration, and site size. Here we investigate the growth behavior of small damage sites on the exit surface of SiO₂ optics under exposure to tightly controlled laser pulses. Results demonstrate that the onset of damage growth is not governed by a threshold, but is probabilistic in nature and depends both on the current size of a damage site and the laser fluence to which it is exposed. We also develop models for use in growth prediction. In addition, we show that laser exposure history also influences the behavior of individual sites.

Sjögren-Larsson syndrome (SLS) is an autosomal recessive disorder characterized by ichthyosis, mental retardation, spasticity and mutations in the ALDH3A2 gene for fatty aldehyde dehydrogenase, an enzyme that catalyzes the oxidation of fatty aldehyde to fatty acid. More than 70 mutations have been identified in SLS patients, including small deletions or insertions, missense mutations, splicing defects and complex nucleotide changes. We now describe 2 SLS patients whose disease is caused by large contiguous gene deletions of the ALDH3A2 locus on 17p11.2. The deletions were defined using long distance inverse PCR and microarray-based comparative genomic hybridization. A 24-year-old SLS female was homozygous for a 352-kb deletion involving ALDH3A2 and 4 contiguous genes including ALDH3A1, which codes for the major soluble protein in cornea. Although lacking corneal disease, she showed severe symptoms of SLS with uncommon deterioration in oral motor function and loss of ambulation. The other 19-month-old female patient was a compound heterozygote for a 1.44-Mb contiguous gene deletion and a missense mutation (c.407C>T, P136L) in ALDH3A2. These studies suggest that large gene deletions may account for up to 5% of the mutant alleles in SLS. Geneticists should consider the possibility of compound heterozygosity for large deletions in patients with SLS and other inborn errors of metabolism, which has implications for carrier testing and prenatal diagnosis., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The influence of laser parameters on laser-induced damage in the bulk of KDP is difficult to determine because the damage manifests as discrete sites a few micrometers in diameter distributed throughout a relatively large volume of material. Here, we present a method to directly measure the size and location of many thousands of such sites and correlate them to the laser conditions that produced them. This technique is used to characterize the effects of pulse duration on damage initiated by 1053 nm light in the bulk of KDP crystals. We find that the density of damage sites produced by 1053 nm light is less sensitive to pulse duration than was previously reported for 526 nm and 351 nm light. In addition, the effect of pulse duration on the size of the damage sites produced appears insensitive to wavelength.

Historically, the rate at which laser-induced damage sites grow on the exit surface of SiO2 optics under subsequent illumination with nanosecond-laser pulses of any wavelength was believed to depend solely on laser fluence. We demonstrate here that much of the scatter in previous growth observations was due to additional parameters that were not previously known to affect growth rate, namely the temporal pulse shape and the size of a site. Furthermore, the remaining variability observed in the rate at which sites grow is well described in terms of Weibull statistics. The effects of site size and laser fluence may both be expressed orthogonally in terms of Weibull coefficients. In addition, we employ a clustering algorithm to explore the multiparameter growth space and expose average growth trends. Conversely, this analysis approach also identifies sites likely to exhibit growth rates outside the norm. The ability to identify which sites are likely to grow abnormally fast in advance of the manifestation of such behavior will significantly enhance the accuracy of predictive models over those based on average growth behaviors.

We have found the local temporal shot-to-shot variation of the NIF high-energy laser system to be relatively constant (~3.4% to 4.2% of the mean fluence). We have developed a statistical model that predicts the maximum fluence distribution any particular location will be exposed to after N independent shots (the so-called max-of-N fluence distribution) using the measured shot-to-shot variance; this method allows for an estimate of maximum optics fluence exposure., (© 2011 Optical Society of America)

Growth of laser damage on SiO(2) optical components used in high power lasers can be reduced or eliminated by pre-exposure to pulses of a few hundred ps in duration. Such pre-exposure would cause weak locations on the optics surface to self-identify by initiating very small damage sites. The sites which initiate will be only a few microns in diameter and will have a very low probability of growing even without any further treatment. Repairing damage sites when small is important because both laser mitigation and acid etching are very successful in preventing such small sites from growing.

Haploinsufficiency of RASA1, located on chromosome 5q14.3, has been identified as the etiology underlying the disorder capillary malformation-arteriovenous malformation (CM-AVM). Recently, haploinsufficiency of MEF2C, located 1.33 Mb distal to RASA1 on chromosome 5q14.3, has been implicated as the genetic etiology underlying a complex array of deficits including mental retardation, hypotonia, absent speech, seizures, and brain anomalies. Here we report a patient who is haploinsufficient in both RASA1 and MEF2C who presents with dermatologic and neurologic abnormalities that constitute a 5q14.3 neurocutaneous syndrome. This finding highlights the need to assess for CM-AVM in patients with neurologic features consistent with MEF2C haploinsufficiency, and vice versa., (Copyright © 2011 Wiley-Liss, Inc.)

Human FOXP2 deficiency has been identified as a cause of hereditary developmental verbal dyspraxia. Another member of the same gene family, FOXP1, has expression patterns that overlap with FOXP2 in some areas of the brain, and FOXP1 and FOXP2 have the ability to form heterodimers. These findings suggest the possibility that FOXP1 may also contribute to proper speech development. However, no such role of FOXP1 has been established to date. Recently, a child was reported who presented with a 3p13-14.1 deletion of four genes, including FOXP1, and a constellation of deficits that included speech delay. In this study, we report the case of a patient with a single deletion of FOXP1. This patient presented with speech and motor developmental delays, a Chiari I malformation, and epileptiform discharges. The nature of the speech deficit is different from the primary oromotor verbal dyspraxia found in patients with FOXP2 deficiency. The patient's developmental deficits may support a role for FOXP1 in the development of verbal and motor skills.

The growth behavior of laser-induced damage sites is affected by a large number of laser parameters as well as site morphology. Here we investigate the effects of pulse duration on the growth rate of damage sites located on the exit surface of fused silica optics. Results demonstrate a significant dependence of the growth parameters on laser pulse duration at 351 nm from 1 ns to 15 ns, including the observation of a dominant exponential versus linear, multiple-shot growth behavior for long and short pulses, respectively. These salient behaviors are tied to the damage morphology and suggest a shift in the fundamental growth mechanisms for pulses in the 1-5 ns range.

We present an empirical model that describes the experimentally observed laser-induced bulk damage and conditioning behavior in deuterated potassium dihydrogen phosphate (DKDP) crystals. The model expands on an existing nanoabsorber precursor model and the multistep absorption mechanism to include two populations of absorbing defects, one with linear absorption and another with nonlinear absorption. We show that this model connects previously uncorrelated small-beam damage initiation probability data to large-beam damage density measurements over a range of nanosecond pulse widths. In addition, this work predicts the damage behavior of laser-conditioned DKDP.

Objective: Essential tremor (ET), one of the most common neurological disorders, comprises uncontrollable tremor, usually in the upper extremities. Idiopathic normal pressure hydrocephalus (iNPH) features ventricular enlargement in the absence of elevated intracranial pressure; its three cardinal symptoms are gait impairment, incontinence, and dementia. iNPH is among the most common medical problems in the older population. To date, the genetic etiologies of ET and iNPH remain largely elusive., Methods: We previously identified a large kindred in which the affected members developed ET in adolescence or young adulthood and iNPH when elderly, in that case called ETINPH. Employing two different genotyping microarrays and two- or multipoint linkage analysis strategies, genome-wide linkage scans were performed., Results: We mapped the ETINPH locus to chromosome 19q12-13.31. Fine-mapping in this region revealed a maximum two-point lod score of 2.8 at rs2023865 and a maximum multipoint lod score of 17.9 at rs9304878. By haplotype construction, a (conservatively) approximately 17-cM critical region from SNP rs11084582 to SNP rs7258420 was defined. This region contains several neuronal genes that constitute tantalizing etiological candidates for ETINPH., Conclusion: The importance of uncovering the genetic etiology of this disorder is irrefutable, as such a discovery could offer valuable insights into ET, iNPH, and related neurological conditions., (Copyright 2010 S. Karger AG, Basel.)

In 1992, van den Ende et al. first reported an autosomal recessive multiple congenital anomaly syndrome characterized by blepharophimosis, arachnodactyly, and congenital contractures in a Brazilian girl born to consanguineous parents. Since then, nine total patients have been reported with van den Ende-Gupta syndrome (VDEGS), and the syndrome's phenotype has been found to also include additional dysmorphic facial features, palatal abnormalities, and slender skeletal features. We present two African-American sisters born to nonconsanguineous parents who have been diagnosed with VDEGS. Both sisters developed stridor and were found to have an unusual malformation characterized by large, globular cuneiform cartilages, shortened aryepiglottic folds, a tightly coiled epiglottis, and laryngomalacia. Both patients underwent supraglottoplasty with a successful outcome. A review of the literature reveals that airway problems have been reported in a previous patient. However, no specific airway anomaly has been reported. We suggest that all patients with VDEGS and stridor undergo direct laryngoscopy with consideration for surgical correction., ((c) 2007 Wiley-Liss, Inc.)

We investigate the interaction of high-power nanosecond-laser pulses at different frequencies with damage initiating defect structures in bulk KD(x)H(2-x)PO(4) (DKDP) crystals in order to enhance the understanding of a) the nature and behavior of the defects involved and b) the laser-induced defect reactions leading to improvement to the material performance. The experimental results indicate that there is more than one type of defect structure giving rise to damage initiation over two different spectral ranges. Moreover, within one set of defects we observe two different damage behaviors depending on the pre-irradiation parameters, pointing to more than one defect reaction pathway.

Laser-induced damage is a key factor that constrains the ways in which optical materials are used in high-power laser systems. We study the size and density of bulk laser-induced damage sites formed during frequency tripling in a DKDP crystal. The characteristics of the damage sites formed during tripling, for which 1053, 526, and 351 nm light is simultaneously present, are compared to those of damage sites formed by 351 nm light alone. The fluence of each wavelength is calculated as a function of depth with a full 4D(x,y,z,t) frequency conversion code and compared with measured damage density and size distributions. The density of damage is found to be governed predominantly by 351 nm light with some lesser, though nonnegligible, contribution from 526 nm light. The 1053 nm light does not appear to contribute to the damage density. The morphology of the damage sites, however, is seen to be relatively insensitive to wavelength and to depend only on total fluence of all wavelengths present. The strong and negligible wavelength dependences of initiation density and damage morphology, respectively, indicate that the dominant energy deposition mechanism varies during the damaging pulse.

Optical breakdown by femtosecond and nanosecond laser pulses in transparent dielectrics produces an ionized region of dense plasma confined within the bulk of the material. This ionized region is responsible for broadband radiation that accompanies the breakdown process. Spectroscopic measurements of the accompanying light have been used to show that, depending on the laser parameters, the spectra may originate from plasma-induced second-harmonic generation, supercontinuum generation, or thermal emission by the plasma. By monitoring the emission from the ionized region, one can ascertain the predominant breakdown mechanism and the morphology of the damage region.

The laser-induced damage performance of potassium dihydrogen phosphate and deuterated potassium dihydrogen phosphate nonlinear optical crystals after pre-exposure to lower-energy laser pulses (laser annealing, also known as laser conditioning) is investigated as a function of wavelength for both the damaging and conditioning pulses. We obtain a quantitative evaluation of the bulk damage performance of these materials by measuring the density of damage events as a function of laser parameters. This new method allows for a detailed assessment of the improvement of material performance from laser conditioning and reveals the key parameters for optimizing performance depending on the operational wavelength.

Laser-induced damage in wide band-gap optical materials is the result of material modifications arising from extreme conditions occurring during this process. The material absorbs energy from the laser pulse and produces an ionized region that gives rise to broadband emission. By performing a time-resolved investigation of this emission, we demonstrate both that it is blackbody in nature and that it provides the first direct measurement of the localized temperature of the material during and following laser damage initiation for various optical materials. For excitation using nanosecond laser pulses, the plasma, when confined in the bulk, is in thermal equilibrium with the lattice. These results allow for a detailed characterization of temperature, pressure, and electron densities occurring during laser-induced damage.

A novel experimental approach is employed to understand the mechanisms of laser induced damage. Using an OPO (optical parametric oscillator) laser, we have measured the damage thresholds of deuterated potassium dihydrogen phosphate (DKDP) from the near ultraviolet into the visible. Distinct steps, whose width is of the order of k(B)T, are observed in the damage threshold at photon energies associated with the number of photons (3-->2 or 4-->3) needed to promote a ground state electron across the energy gap. The wavelength dependence of the damage threshold suggests that a primary mechanism for damage initiation in DKDP is a multiphoton process in which the order is reduced through excited defect state absorption.

1. The electronegative membranes described in the literature which show a high degree of ionic selectivity (permitting cations to pass and restricting the anions) have serious shortcomings: their absolute permeability is extremely low, much too small for convenient experimentation; their ionic selectivity in most cases is not as perfect as would be desirable, and is moreover adversely affected by prolonged contact with electrolyte solutions. 2. A method has been worked out to prepare membranes substantially free from these defects. Porous collodion membranes were cast on the outside of rotating tubes and then oxidized with 1 M NaOH. By allowing the oxidized porous membranes to dry in air on the tubes membranes of desirable properties are obtained. These membranes are smooth, have a well defined shape, and allow considerable handling without breaking. 3. This new type membrane when tested for ionic selectivity by the measurement of the "characteristic concentration potential," consistently gives potentials of 54 to 55 mv., the maximum thermodynamically possible value (at 25 degrees C.) being 55.1 mv. This high degree of ionic selectivity is not lost on prolonged contact with water, and is only very slowly affected by electrolyte solutions. 4. The absolute permeability of the new type membranes can be varied over a very wide range by changing the time of oxidation. Under optimum conditions membranes can be obtained with a resistance in 0.1 N KCl solution of only 0.5 ohms per 50 cm.(2) membrane area. The absolute rate of cation exchange through these membranes between solutions of different uni-univalent electrolytes is very high, in one case, e.g. 0.9 m.eq. cations per 4 hours, the anion leak being 0.02 m.eq. Thus, the absolute permeability of the new type membranes is two to four orders of magnitude greater than the permeability of the dried collodion membranes and the oxidized ("activated") dried collodion membranes used heretofore. Because of the characteristic properties of the new type membranes the term "megapermselective" (or "permselective") collodion membranes is proposed for them.

1. Experiments were carried out to decide whether a homogeneous phase (solubility) theory or a micellar-structural theory more adequately describes the behavior of dried collodion membranes with solutions of strong electrolytes. 2. A number of dried collodion membranes were prepared from an electrochemically inactive collodion preparation (state I); the characteristic concentration potentials across them were low, about 30 mv. The membranes were activated by oxidation (state II) to give maximum or nearly maximum concentration potentials (about 50 mv.). The oxidized membranes are dried, dissolved in alcohol-ether, and a new set of dry collodion membranes prepared from this solution (state III). The concentration potentials across these membranes are low. 3. Since the properties of a homogeneous phase should not be influenced by a rearrangement of its constituent particles, the experimental results do not support a homogeneous phase (solubility) theory, but they agree with the predictions of the micellar-structural theory. The characteristic behavior of dried collodion membranes in solutions of strong inorganic electrolytes is therefore due to the micellar character of its interstices.