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This paper describes the long-term, satellite-based visible snow cover extent NOAA climate data record (CDR) currently available for climate studies, monitoring, and model validation. This environmental data product is developed from weekly Northern Hemisphere snow cover extent data that have been digitized from snow cover maps onto a Cartesian grid draped over a polar stereographic projection. The data has a spatial resolution of 190.5 km at 60° latitude, are updated monthly, and span from 4 October 1966 to present. The data comprise the longest satellite-based CDR of any environmental variable. Access to the data are provided in netCDF format and are archived by the National Climatic Data Center (NCDC) of the National Oceanic and Atmospheric Administration (NOAA) under the satellite climate data record program (doi:10.7289/V5N014G9). The basic characteristics, history, and evolution of the dataset are presented herein. In general, the CDR provides similar spatial and temporal variability as its widely used predecessor product. Key refinements to the new CDR improve the product's grid accuracy and documentation, and bring metadata into compliance with current standards for climate data records. [ABSTRACT FROM AUTHOR]

Spring snow cover across Arctic lands has, on average, retreated ~5 days earlier since the late 1980s compared to the previous 20 years. However, it appears that since about the late 1980s the date the snowline first retreats north during the spring has changed only slightly: in the last ~20 years snow has not been disappearing significantly earlier. Snowmelt changes observed since the late 1980s have been step-like, unlike the more continuous downward trend seen in Arctic sea-ice extent. At 70° N, several longitudinal segments (of 10 °) show significant (negative) trends, while only two longitudinal segments at 608N show significant trends, one positive and one negative. These variations appear to be related to variations in the Arctic Oscillation (AO). When the springtime AO is strongly positive, snow melts earlier. When it is strongly negative, snow disappears later in the spring. The winter AO is less straightforward. At higher latitudes (70 °N), a positive AO during the winter months is correlated with later snowmelt, but at lower latitudes (50 °N and 60 °N) a positive wintertime AO is correlated with earlier snowmelt. If the AO during the winter months is negative, the reverse is true. Similar stepwise changes (since the late 1980s) have been noted in sea surface temperatures and in phytoplankton abundance as well as in snow cover. [ABSTRACT FROM AUTHOR]

Abstract: Charcot-Marie-Tooth disease limits hand function. Tendon transfer has not been reported in pediatric CMT. We report two severely affected children following long finger flexor digitorum superficialis opposition tendon transfer. Improvement was noted in palmar abduction, (30°/40°), opposition, (thumb to all digits), and acquisition of pincer, palmar, and lateral pinch with measureable force (1lb). Dexterity testing improved on the 9 Hole Peg Test (1.03s/77s, 22s) and Functional Dexterity Test (13s/33s, 88s). Functional improvements were observed in self feeding, clothing management, and play. These cases support flexor digitorum superficialis opposition tendon transfer surgery to improve hand function in children with CMT. [Copyright &y& Elsevier]

Spring snow cover over Arctic lands has, on average, melted approximately 4-7 days earlier since the late 1980s compared to the previous 20 years. The earlier disappearance of snow has been identified in non-mountainous regions at the 60° and 70°N parallels over Eurasia and North America using visible satellite observations of continental snow cover extent (SCE) mapped by the National Oceanic and Atmospheric Administration (NOAA). The change was greater in the farthest north continental locations. Northern Hemisphere SCE declined by almost 10% (May) to 20% (June) between the two intervals. At latitude 70°N, eight segments of longitude (each 10° in width) show significant (negative) trends. However, only two longitudinal segments at 60°N show significant trends, one positive and one negative. SCE changes coincide with increasing spring warmth and the earlier diminution of sea ice in the last several decades. However, while sea ice has continued to decrease during this recent interval, snowmelt dates in the Arctic changed in a step-like fashion during the mid to late 1980s and have remained much the same since that time. [ABSTRACT FROM AUTHOR]

Non-ambulatory patients with Duchenne muscular dystrophy (DMD) have arm weakness limiting anti-gravity movement resulting in severe functional impairments. The Wilmington Robotic Exoskeleton (WREX), by employing a unique 4 bar link technology married with a variable linear elastic band power source, allows for 3 dimensional gravity reduced movement of the arms to enhance function for the completion of Activities of Daily Living (ADL). To establish the utility of WREX in patients with DMD, we report our experience from 2011 to 2014. Nine boys with DMD, aged 11–17y/o (median age 16y/o), were evaluated. Active range of motion (AROM) and functional task completion (self-feeding, drinking from a glass, access to face for grooming, manage eyeglasses, and access their environment, computer, cell phone, and other technology) were completed both with and without the WREX. AROM (without WREX/with WREX) was the following: shoulder flexion 0–30 degrees/45–100 degrees, shoulder abduction 0–30 degrees/45–100 degrees, and elbow flexion was 0–100 degrees/80–120 degrees. With the WREX, all patients demonstrated increased functional skills, especially the ability to self-feed, access joystick, access face for grooming, and reach away from the body to use technology. We conclude WREX provides a decreased gravity environment that allows for significant increased AROM at the shoulder and elbow joints. In addition, WREX allows for the patients to reach away from the body and across midline, improved independence with ADL completion, as well as increased safety in the home and community. WREX may also improve psychosocial wellbeing as all patients demonstrated a positive emotional response to WREX use. [ABSTRACT FROM AUTHOR]

Charcot–Marie–Tooth disease (CMT) has diverse clinical presentations and molecular genetic heterogeneity. Herein we describe the clinical features, neurophysiological and morphological studies of 2 fatal cases of CMT. Case 1 was a healthy newborn who developed foot drop, daily frequent vomiting and severe constipation at 7 months of age. His arm and leg weakness rapidly progressed within a few months. He subsequently developed diaphragmatic paralysis and died at 2.5 years of age due to respiratory failure. NCS/EMG showed a severe, axonal sensory and motor neuropathy. He had a novel and de novo mutation (c.296–297dupAAG) of the MFN2 gene. Case 2 had congenital hypomyelinating neuropathy confirmed by NCS and nerve biopsy, associated with a novel and de novo missense mutation (p.His384Arg) of the EGR2 gene. The patient presented a few weeks after birth with failure to thrive and hypotonia. She had facial, severe proximal > distal arm and leg weakness, pain insensitivity, areflexia and symptoms of autonomic dysfunction. She progressed to respiratory failure requiring mechanical ventilation. Her CSF protein was elevated (136 mg/dl). She had a fluctuating clinical course that let to the initial consideration of chronic inflammatory demyelinting polyneuropathy. She did not respond to prednisone, but she responded to IVIG therapy initially with some improvement of muscle strength and decrease autonomic dysfunction. She subsequently experienced deterioration of weakness not responding to either IVIG or plasmapheresis, and died at 16.5 months of age. Our report expanded the genotype and phenotype of MFN2 and EGR2 mutations. Although early onset CMT has been well described, autonomic features and fatality due to respiratory failure are rarely described. MFN2 mutations frequently cause severe phenotype, but diaphragmatic paralysis and autonomic dysfunction have not been described. Similarly, severe autonomic dysfunction has not been reported to be associated with EGR2 mutations. [ABSTRACT FROM AUTHOR]

TRPV4 gene mutations are known to cause 5 skeletal dysplasias, 1 arthropathy and 3 forms of neuropathies: congenital distal spinal muscular atrophy (CDSMA), scapuloperoneal spinal muscular atrophy (SPSMA) and Charcot-Marie-Tooth disease type 2C (CMT2C). We report 5 patients with TRPV4 related neuropathies, three of whom have positive family histories. Three patients share the common p.Arg269His mutation but have varied phenotypes. Patients 1 and 2 presented with arthrogryposis multiplex congenital (AMC), hip dysplasia, scoliosis, distal > proximal weakness in lower extremities (LE) with limited walking, and weakness of proximal upper extremities (UE). Patient 3 with the p.Arg269His has CMT2 with pure axonal neuropathy, which she inherited from her subclinically affected mother with evidence of mild chronic denervation on EMG. Her maternal uncle and cousin, also with p.Arg269His, had AMC, motor axonal neuropathy and severe course: uncle lost ambulation in his 40s; her cousin never walked. Patient 4 has AMC with limited walking since 2.5 years, distal > proximal weakness in LE, mild proximal UE weakness and prominent scapulae. He has 2 mutations: p.Val620Ile – seen in CMT2C and brachyolmia type 3, but not in CDSMA; and p.Arg151Trp seen with low frequency in dbSNP. Patient 5 is a 3 y/o with gait abnormalities and axonal neuropathy with a similarly affected father and grandmother. His p.Arg186Gln is a known CMT2C mutation. All 5 patients reported have pure motor axonal neuropathy. Muscle ultrasound in all showed a neurogenic pattern and fasciculations. The broad spectrum of TRPV4 neuropathies presents diagnostic and management dilemmas without a genotype: phenotype correlation, as demonstrated by CMT2C and CDSMA phenotypes in patient 3 family. Patients with AMC had proximal UE weakness and scapular winging, showing an overlap between CDSMA and SPSMA. TRPV4 gene mutations should be considered in all cases of AMC presentation with evidence of axonal neuropathy. [ABSTRACT FROM AUTHOR]