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In this article, a regional ocean surface waves dataset from Sentinel‐1 A and B Synthetic Aperture Radar (SAR) satellites has been described. The ocean wave data have been extracted from the Sentinel‐1 level‐2 OCN (ocean) product as provided by the European Space Agency and downloadable for this region from the Copernicus Australasia regional data hub. The source OCN data have been produced by evolving versions of Sentinel‐1 Instrument Processing Facility (IPF). The structure of the source OCN NetCDF files changes over time and presents a challenge in performing long duration, time series analyses, including the examination of potential inconsistencies in OCN wave data, due to employment of different IPF versions over the duration of the satellite missions. Here, the input OCN wave data have been homogenized to a single, easily usable standard format after applying a quality assurance and control procedure that removes various inconsistencies in variables, coordinates, dimensions and land flag, and through the addition of new auxiliary variables. The new format has the desirable properties of being compact in size, consistent in structure, and scalable in temporal and spatial coverage. It is also convenient to use and offers opportunities to perform fast, multi‐year regional processing and analysis for calibration and validation studies and scientific applications. No re‐processing of Sentinel‐1 level‐1 data has been carried out in this work. [ABSTRACT FROM AUTHOR]

Hereditary hair loss in human is a group of clinically and genetically heterogeneous disorders. It is characterized by sparse to complete absence of hair on the scalp and other parts of the body. In few cases tightly curled twisted wooly hair (WH) on the scalp has been reported as well. The hair loss disorders, including both syndromic and non-syndromic (isolated) forms, segregate either in autosomal dominant or autosomal recessive pattern. To date, seven autosomal dominant and equal numbers of autosomal recessive isolated forms of hair loss disorders have been characterized. Genes responsible for causing most of these disorders have been identified. In this review, we have provided an update on clinical and genetic aspects of isolated hereditary hair loss disorders manifesting with hypotrichosis and/or WHs. Because most of the recessive genes have been mapped using consanguineous families of Pakistani origin, therefore emphasis is given to mutations identified in these families. OMIM nomenclature has been followed to indicate different forms of hair loss disorders. [ABSTRACT FROM AUTHOR]

ABSTRACT Fatigue is one of the principle damage mechanisms in materials especially at elevated temperatures. It possesses a great influence on the material properties and the possible working life. In this work, a novel technique for the analysis of fatigue at elevated temperature is suggested. Material fundamental frequency and its drop are used as the key parameters to predict the remaining useful life of a selected shape specimen, which is operated under low-cyclic fatigue loading at elevated temperature. Experiments are performed on aluminium 1050 with two different lengths of a non-prismatic cantilever beam at room temperature, 100, 200 and 300 °C, respectively. The experimental data is further transformed in to an empirical correlation that can predict specimen useful life. The error in this life prediction is less than 5%, and it reduces more once the frequency drop is increased. [ABSTRACT FROM AUTHOR]

Artificial cognitive systems are increasingly drawn towards 'human‐like' gestural exhibits while performing various manipulative acts. Representing such actions in a natural settings requires temporal extractions of their grasp progressions. A novel optimisation‐based hidden Markov framework is offered, to generate natural hand prehensions through maximisation of a composite grasp function built of individual finger trajectory likelihoods. In order to produce the desired motion in an intuitive framework, the final grasp frame (represented in terms of standard discriminants z ∈ ℜ2 in a condensed grasp eigen‐space) is extended in a temporal sequence by equi‐spaced increments of z, over their conventional joint‐space representations. [ABSTRACT FROM AUTHOR]

A 3D printed microfluidically‐controlled metal‐coated waveguide single‐pole double‐throw (SPDT) switch is presented, which is both light weight and has low power consumption, exhibiting good performance at K‐band. Oil (ON state) and EGaIn metal (OFF state) liquids are used for switching control. The proposed switch exhibits its best performance at 18 GHz, with insertion loss below 0.2 dB, return loss of 19.5 dB, and isolation better than 25 dB. [ABSTRACT FROM AUTHOR]

Grasping postures on a human hand are generated by an effective combination of spatial motions and contact forces on individual finger linkages. The rich kinematic redundancy within its anatomy, poses critical control challenges, while emulating natural prehensile actions. A simplified grasp‐formulation resolution is presented, by proposing a virtual‐object imagery to define generic grasp enaction sequences. The same are conceived and controlled by a set of contact points on the imagined grasp‐sphere, whose spatial conformation is guided by a serial‐haptic interface. The kinaesthetic cognitions along with visual feed to an operator ushers a reliable framework for grasp execution and transfer to a robot hardware without resorting to supplementary mapping mechanisms. Stable grasps on the anthropomorphic robot set‐up portrays a systematic procedure to transcribe human‐like postural attributes, aided with somesthetic and visual sensations that are anticipated to steer remote operator controls. [ABSTRACT FROM AUTHOR]

Lee K, Khan S, Islam A, Ansar M, Andrade PB, Kim S, Santos-Cortez RLP, Ahmad W, Leal SM. Novel TMPRSS3 variants in Pakistani families with autosomal recessive non-syndromic hearing impairment. Mutations in the TMPRSS3 gene are known to cause autosomal recessive non-syndromic hearing impairment (ARNSHI). After undergoing a genome scan, 10 consanguineous Pakistani families with ARNSHI were found to have significant or suggestive evidence of linkage to the TMPRSS3 region. In order to elucidate if the TMPRSS3 gene is responsible for ARNSHI in these families, the gene was sequenced using DNA samples from these families. Six TMPRSS3 variants were found to cosegregate in 10 families. None of these variants were detected in 500 control chromosomes. Four novel variants, three of which are missense [c.310G>A (p.Glu104Lys), c.767C>T (p.Ala256Val) and c.1273T>C (p.Cys425Arg)] and one nonsense [c.310G>T (p.Glu104Stop)], were identified. The pathogenicity of novel missense variants was investigated through bioinformatics analyses. Additionally, the previously reported deletion c.208delC (p.His70ThrfsX19) was identified in one family and the known mutation c.1219T>C (p.Cys407Arg) was found in five families, which makes c.1219T>C (p.Cys407Arg) as the most common TMPRSS3 mutation within the Pakistani population. Identification of these novel variants lends support to the importance of elements within the low-density lipoprotein receptor A (LDLRA) and serine protease domains in structural stability, ligand binding and proteolytic activity for proper TMPRSS3 function within the inner ear. [ABSTRACT FROM AUTHOR]

Khan S, Basit S, Zimri FK, Ali N, Ali G, Ansar M, Ahmad W. A novel homozygous missense mutation in WNT10B in familial split-hand/foot malformation. Split-hand/foot malformation (SHFM) is a rare limb developmental malformation, characterized by variable degree of median clefts of hands and feet due to the absence of central rays of extremities. To date, six different forms of SHFM have been described. Four of these SHFM1, SHFM3, SHFM4 and SHFM5 show autosomal dominant, SHFM6 autosomal recessive and SHFM2 X-linked pattern of inheritance. In this study a large consanguineous Pakistani family, with autosomal recessive SHFM, appeared in the last two generations, was investigated. In total 15 individuals including 9 males and 6 females were affected with the syndrome. Affected members of the family exhibited SHFM phenotype with involvement of hands and feet. Most of the affected members showed syndactyly/polydactyly in hands and feet, dysplastic hand, aplasia of radial ray of hand and cleft foot. Investigating linkage to known autosomal SHFM loci mapped the family to SHFM6 locus on chromosome 12p11.1-q13.13. Mutation screening of the gene WNT10B revealed a novel sequence variant (c.986C>G, p.Thr329Arg) in all affected individuals who were studied. This is the third mutation reported in gene WNT10B causing autosomal recessive SHFM syndrome. [ABSTRACT FROM AUTHOR]

To extend the predictive capability of existing crack growth models for fibre metal laminates under constant amplitude fatigue loading to variable-amplitude loading, further research on variable-amplitude fatigue mechanisms in fibre metal laminates is necessary. In response to this need, an experimental study into the effects of multiple overloads, underloads and various block-loading sequences on crack growth in the fibre metal laminate Glare was investigated. Crack growth retardation effects were observed in the tests; however, the magnitude of these effects was lower than seen in monolithic aluminium because of fibre bridging. As a result, predictions of the observed behaviour were attempted using an existing constant-amplitude fatigue crack growth model for Glare in combination with a linear damage accumulation law. [ABSTRACT FROM AUTHOR]

• Nodulated lupins ( Lupinus angustifolius cv. Wonga) were hydroponically grown under conditions of low phosphate (LP) or adequate phosphate (HP) to assess the effect of phospho enolpyruvate carboxylase (PEPC)-derived organic acids on nitrogen assimilation in LP nodules. • LP conditions are linked to altered organic acid metabolism, by the engagement of PEP metabolism via PEPC. In LP nodules, the enhanced organic acid synthesis may reduce the available organic carbon for nitrogen assimilation. The diversion of carbon between the organic acid- and amino acid pools was assessed through key nodular enzymes and 14CO2 metabolism. • Under LP conditions, increased rates of organic acid synthesis via PEPC and malate dehydrogenase (MDH), coincided with reduced nitrogen assimilation via aspartate aminotransferase (AAT), aspartate synthetase (AS) and glutamine synthetase (GS)/glutamate synthase (GOGAT) activities. There was a preferential metabolism of nodular 14CO2 into organic acids and particularly into malate. High malate levels were associated with reduced N2 fixation and synthesis of amino acids. • These results indicate that phosphorus deficiency can enhance malate synthesis in nodules, but that excessive malate accumulation may inhibit N2 fixation and nitrogen assimilation. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Changes to cardiac matrix are central to ventricular remodelling after acute MI and matrix metalloproteinase expression is implicated in this process. We investigated the temporal profile of MMP-3 and its relationship to LV dysfunction and prognosis following AMI. Methods: We studied 382 patients with AMI. Plasma MMP-3 was measured at 0–12, 12–24 h and for subsequent 24 h periods during admission. LV function (LVEF) was assessed by echocardiography pre-discharge and at a median of 148 days and clinical endpoints at a median of 313 days. Results: MMP-3 peaked prior to discharge thus pre-discharge levels were used in analyses. MMP-3 was associated with patient age (p <0.001), creatinine (p <0.001) and was higher in males (p <0.001) and hypertensives (p <0.001). MMP-3 inversely correlated with LVEF at follow-up (p =0.043), was higher in subjects with LVEF <40% (p =0.017) and in subjects with increasing EDV (p =0.017) or ESV (p =0.007) compared to those in whom volumes fell between visits. In the 58 patients reaching the endpoint of death or heart failure, MMP-3 was higher (p <0.001). On Kaplan–Meier analysis, subjects with levels above optimum cut off identified via ROC curves were more likely to suffer a clinical event (p =0.037). Conclusion: MMP-3 is associated with left ventricular dysfunction, adverse left ventricular remodelling and prognosis after AMI. [Copyright &y& Elsevier]

Two isolates of Colletotrichum musae (CM100 and CM103) which differed significantly in their sensitivity to the fungicides thiabendazole (TBZ) and imazalil were grown on malt extract agar amended with the following antioxidants: ascorbic acid, benzoic acid, butylated hydroxyanisole (BHA), butylated hydroxytoluene, dimethyl sulphoxide, propionic acid, propyl gallate (PG), propyl paraben (PP) and thiourea. The compounds showing the greatest antifungal activity were BHA, benzoic acid, PG and PP. At concentrations of 15 mm or less, these chemicals inhibited conidial germination (at 72 h) and mycelial growth (by day 14) of isolate CM100 and gave high levels of inhibition of isolate CM103. Combinations of low concentrations of BHA (0·5 mm) and imazalil (1·8 µm) completely prevented mycelial growth and germination of the two isolates tested in vitro and showed some synergism when combined at even lower concentrations of BHA. BHA, PP and benzoic acid, in combination with each other and with imazalil and TBZ, applied to banana stalk tissues and crowns previously inoculated with C. musae, were less effective at controlling the fungus in vivo compared with inhibiting mycelial growth and conidial germination in vitro. BHA at 5 mm inhibited fungal growth at 25°C by 35–41%. When BHA (5 mm) was combined with imazalil (0·45 mm), better control (63–80% inhibition) of simulated crown rot was achieved than when imazalil (1·78 mm) or TBZ (2·46 mm) were applied on their own (53–58% and 43–54% inhibition, respectively). The results suggest that BHA, which is a food-grade chemical, might have the potential to enhance the activity of fungicides currently used to control C. musae on bananas, allowing lower concentrations of fungicide to be used. [ABSTRACT FROM AUTHOR]

Kangerlussuaq Glacier (KG) is a major contributor to central‐eastern Greenland mass loss, but existing estimates of its mass balance over the last century are inconsistent, and specific drivers of change remain poorly understood. We present a novel approach that combines numerical modeling and a 1933–2021 climate forcing to reconstruct its mass balance over the past century. The model's final state aligns remarkably well with present‐day observations. The model reveals a total ice mass loss of 285 Gt over the past century, equivalent to 0.68 mm global sea level rise, 51% of which occurred since 2003 alone. Dynamic thinning from ice front retreat is responsible for 88% of mass change since 1933, with short‐term ice front variations having minimal impact on centennial mass loss. Compared to earlier studies, our findings suggest that KG lost 59% (or 301 Gt) less mass over the century than previously thought. Plain Language Summary: Kangerlussuaq Glacier (KG) is a primary source of mass loss from the central‐eastern sector of the Greenland Ice Sheet. Despite various efforts, there is still disagreement on how much mass KG has lost over the past century and the reason for the mass loss. We used computer models and climate data to determine that the glacier has lost 285 billion metric tons of ice over the last 100 years. That is enough to raise global sea levels by about two‐thirds of a millimeter. Over half of this ice loss has happened in the last 20 years, and the rates of mass loss in the past two decades were significantly higher than for most of the last century. While the ice front of the glacier can retreat without losing mass, if the snowfall is significant enough, we found that most ice loss was related to the glacier retreating. This new estimate of ice loss is 59% lower than previous studies suggested, showing that the glacier's decline is less severe than we thought. Key Points: Dynamic thinning due to the retreat of the ice front explains 88% of the mass loss since 1933Short‐term variability in the ice front has a lesser impact on the mass balance on centennial time scalesKangerlussuaq Glacier lost 59% (or 301 Gt) less mass over the century than previously thought [ABSTRACT FROM AUTHOR]

We read with great interest the "rapid review" by Mullins I et al i . on pregnant patients who had contracted coronavirus[1]. They analyzed 32 cases affected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in pregnancy and concluded that SARS-CoV-2 may have a lower mortality rate compared with two other strains of coronavirus, severe acute respiratory syndrome (SARS-CoV) and Middle East respiratory syndrome (MERS-CoV). The 2019 novel coronavirus disease (COVID-19), caused by SARS-CoV-2, first emerged in December 2019 in Wuhan, the capital of Hubei province in China[2]. [Extracted from the article]

ABSTRACT An incidental finding of pseudomyxoma peritonei is reported in a woman with a 6-month history of postmenopausal bleeding. A transvaginal ultrasound scan revealed a poorly defined echogenic mass in the right iliac fossa above the right ovary and free fluid of mixed echogenicity in the pouch of Douglas. Laparoscopic appendicectomy and aspiration of mucinous fluid was performed without adjuvant chemotherapy. Regular postoperative follow-up scans, which are needed as the disease may have an indolent course, showed no signs of recurrence. The differential diagnosis and management of pseudomyxoma peritonei are discussed. [ABSTRACT FROM AUTHOR]

Greenland's bedrock responds to ongoing ice loss with an elastic vertical land motion (VLM) that is measured by Greenland's Global Navigation Satellite System (GNSS) Network (GNET). The measured VLM also contains other contributions, including the long‐term viscoelastic response of the Earth to the deglaciation of the last glacial period. Greenland's ice sheet (GrIS) produces the most significant contribution to the total VLM. The contribution of peripheral glaciers (PGs) from both Greenland (GrPGs) and Arctic Canada (CanPGs) has not carefully been accounted for in previous GNSS analyses. This is a significant concern, since GNET stations are often closer to PGs than to the ice sheet. We find that, PGs produce significant elastic rebound, especially in North and East Greenland. Across these regions, the PGs produce up to 32% of the elastic rebound. For a few stations in the North, the VLM from PGs is larger than that due to the GrIS. Plain Language Summary: The solid Earth has long been compressed by the weight of overlying ice caps and ice sheets. As climate change causes ice to melt, and these loads diminish, the solid Earth relaxes, producing instantaneous elastic rebound and delayed viscoelastic rebound of the bedrock. Such displacements are recorded by the 58 permanent Global Navigation Satellite System (GNSS) stations that comprise the Greenland GNSS Network (GNET). So far, only the ice mass changes from the ice sheet have been considered in the analyses of deformation recorded by GNET. Here, we evaluate the contribution from the peripheral glaciers, which are often much closer to the stations than the ice sheet. We find that at many stations, the signal produced by the peripheral glaciers is non‐negligible, especially in North and East Greenland. This allows us to better understand the residual rebound signal produced by the end of the last ice age. Key Points: Elastic rebound due to ice loss from peripheral glaciers can exceed that due to ice sheet lossThis effect is most significant at Global Navigation Satellite System Network (GNET) sites in North and East GreenlandPeripheral glacier loss should be acknowledged when isolating glacial isostatic adjustment from GNET [ABSTRACT FROM AUTHOR]

Artificial cognitive systems are increasingly drawn towards human-like' gestural exhibits while performing various manipulative acts. Representing such actions in a natural settings requires temporal extractions of their grasp progressions. A novel optimisation-based hidden Markov framework is offered, to generate natural hand prehensions through maximisation of a composite grasp function built of individual finger trajectory likelihoods. In order to produce the desired motion in an intuitive framework, the final grasp frame (represented in terms of standard discriminants z ∈ R² in a condensed grasp eigen-space) is extended in a temporal sequence by equi-spaced increments of z, over their conventional joint-space representations. [ABSTRACT FROM AUTHOR]

A 3D printed micro uidically-controlled metal-coated waveguide single-pole double-throw (SPDT) switch is presented, which is both light weight and has low power consumption, exhibiting good performance at K-band. Oil (ON state) and EGaIn metal (OFF state) liquids are used for switching control. The proposed switch exhibits its best performance at 18 GHz, with insertion loss below 0.2 dB, return loss of 19.5 dB, and isolation better than 25 dB. [ABSTRACT FROM AUTHOR]

A response by S. I. Khan and colleagues to a letter to the editor about their article "Unexpected factors affecting the excitability of human motoneurones in voluntary and stimulated contractions," in the May 15, 2016 issue is presented.

An abstract of the article "First report of 'Candidatus Phytoplasma fraxini' (group 16SrVII phytoplasma) associated with a peach disease in Canada," by S. Zunnoon-Khan and colleagues is presented.

A letter to the editor is presented in response to articles about the diagnosis of dengue fever presented in the previous studies concerning the viral disease.

Lung cancer is one of the most profound causes of cancer‐related deaths in the world. Early detection is known to significantly improve the chances of survival. Several detection and diagnostic methods are used for this purpose. CT is one of the most widely used non‐invasive medical imaging modalities in this domain. The biggest challenge faced by radiologists in this case is detection and diagnosis of cancerous lung nodules. The growth of ground glass opacity (GGO) lesions is an indication of malignancy. However, GGO is difficult to capture for physicians as it manifests in the form of tiny, faint shadows. This research paper proposes an approach for aiding GGO identification in CT lung images for improved lung cancer prognosis. In the proposed approach, morphological reconstruction is used for segmentation. Once the region of interest (ROI) is extracted, statistical analysis using mean, standard deviation, variance, entropy, skewness, kurtosis, minimum grey scale value, maximum grey scale value and range is performed. The same statistical measures are determined for normal lung and distribution plot is drawn for comparison. It is observed that maximum grey‐scale value demonstrates minimum overlap of approximately 7.4%. To reduce this, a joint feature by summing values of feature mean, skewness, and maximum grey‐scale value was used. This approach reduced the overlap to approximately 1.32%. Lastly, ANN was used for classification of GGO and non‐GGO lung tissue with an achieved accuracy of 99.5%. [ABSTRACT FROM AUTHOR]

The observed crustal uplift rates in Greenland are caused by the combined response of the solid Earth to both ongoing and past surface mass changes. Existing elastic Earth models and Maxwell linear viscoelastic GIA (glacial isostatic adjustment) models together underpredict the observed uplift rates. These models do not capture the ongoing mantle deformation induced by significant ice melting since the Little Ice Age. Using a simple Earth model within a Bayesian framework, we show that this recent mass loss can explain the data‐model misfits but only when a reduced mantle strength is considered. The inferred viscosity for sub‐centennial timescale mantle deformation is roughly one order of magnitude smaller than the upper mantle viscosity inferred from GIA analysis of geological data. Reconciliation of geological sea‐level and modern crustal motion data may require that the model effective viscosity be treated with greater sophistication than in the simple Maxwell rheological paradigm. Plain Language Summary: There are 57 permanent Global Navigation Satellite System (GNSS) stations on bedrock in Greenland. These stations provide point‐measurements of three‐dimensional crustal motion. We can model a large portion of the observed crustal uplift rates as elastic Earth response to ongoing rates of ice‐mass loss. We model the remaining part of the uplift rates as the ongoing viscous response of the solid Earth to past ice‐ocean mass exchange—a process termed glacial isostatic adjustment (GIA). Earth structure and deglaciation history in GIA models are usually constrained by geological data that record paleo sea level and past ice margins. To fully explain the GNSS‐measured uplift rates, we propose that these geologically constrained GIA models should additionally resolve: (a) ice‐mass changes during and after the Little Ice Age; and (b) broadband mantle relaxation processes. While such features are challenging to implement, they offer a more granular model paradigm appropriate to the improved temporal sampling that the collective geological and geodetic data sets now provide. Key Points: GIA models constrained by geological data underpredict the modern crustal uplift rates corrected for the elastic loading effectsMass loss since the Little Ice Age explains the residual uplift rates provided a reduced mantle viscosity on sub‐centennial timescalesReconciling geological and modern geodetic data requires a more sophisticated mantle rheology model than generally used in loading studies [ABSTRACT FROM AUTHOR]

The observed crustal uplift rates in Greenland are caused by the combined response of the solid Earth to both ongoing and past surface mass changes. Existing elastic Earth models and Maxwell linear viscoelastic GIA (glacial isostatic adjustment) models together underpredict the observed uplift rates. These models do not capture the ongoing mantle deformation induced by significant ice melting since the Little Ice Age. Using a simple Earth model within a Bayesian framework, we show that this recent mass loss can explain the data‐model misfits but only when a reduced mantle strength is considered. The inferred viscosity for sub‐centennial timescale mantle deformation is roughly one order of magnitude smaller than the upper mantle viscosity inferred from GIA analysis of geological data. Reconciliation of geological sea‐level and modern crustal motion data may require that the model effective viscosity be treated with greater sophistication than in the simple Maxwell rheological paradigm. Plain Language Summary: There are 57 permanent Global Navigation Satellite System (GNSS) stations on bedrock in Greenland. These stations provide point‐measurements of three‐dimensional crustal motion. We can model a large portion of the observed crustal uplift rates as elastic Earth response to ongoing rates of ice‐mass loss. We model the remaining part of the uplift rates as the ongoing viscous response of the solid Earth to past ice‐ocean mass exchange—a process termed glacial isostatic adjustment (GIA). Earth structure and deglaciation history in GIA models are usually constrained by geological data that record paleo sea level and past ice margins. To fully explain the GNSS‐measured uplift rates, we propose that these geologically constrained GIA models should additionally resolve: (a) ice‐mass changes during and after the Little Ice Age; and (b) broadband mantle relaxation processes. While such features are challenging to implement, they offer a more granular model paradigm appropriate to the improved temporal sampling that the collective geological and geodetic data sets now provide. Key Points: GIA models constrained by geological data underpredict the modern crustal uplift rates corrected for the elastic loading effectsMass loss since the Little Ice Age explains the residual uplift rates provided a reduced mantle viscosity on sub‐centennial timescalesReconciling geological and modern geodetic data requires a more sophisticated mantle rheology model than generally used in loading studies [ABSTRACT FROM AUTHOR]

Usher syndrome (USH) is a hereditary disorder associated with sensorineural hearing impairment, progressive loss of vision attributable to retinitis pigmentosa (RP) and variable vestibular function. Three clinical types have been described with type I (USH1) being the most severe. To date, six USH1 loci have been reported. We ascertained two large Pakistani consanguineous families segregating profound hearing loss, vestibular dysfunction, and RP, the defining features of USH1. In these families, we excluded linkage of USH to the 11 known USH loci and subsequently performed a genome-wide linkage screen. We found a novel USH1 locus designated USH1H that mapped to chromosome 15q22-23 in a 4.92-cM interval. This locus overlaps the non-syndromic deafness locus DFNB48 raising the possibility that the two disorders may be caused by allelic mutations. [ABSTRACT FROM AUTHOR]

Introduction: The ~31-km-wide Hiawatha structure, located beneath Hiawatha Glacier in northwestern Greenland, has been proposed as an impact structure that may have formed after the Pleistocene inception of the Greenland Ice Sheet [1]. However, available age constraints for the Hiawatha structure have only been tentative. The bedrock under the structure is likely a continuation of the highly metamorphosed 1.95-1.75 Ga [2] bedrock exposed immediately adjacent to Hiawatha Glacier, providing a maximum constraint on the structure's age [1]. Further age estimates have been based on indirect constraints, such as estimates of erosion rates and the structure's relationship to the Greenland Ice Sheet [1]. Here we dated the structure using detrital materials sampled immediately downstream thereof. We report 40Ar/39Ar analyses of impact-related glaciofluvial sand collected in 2016 and U-Pb analyses of shocked zircon from pebble-sized glaciofluvial clasts of impact melt rock collected in 2019. Results: Of the 50 grains that underwent 40Ar/39Ar step-heating analysis, 29 developed 'U'- or 'saddle'-shaped age spectra, with 23 giving minimum apparent ages in the Paleocene. Two mini-plateaus gave Late Paleocene ages of 58.5 ± 0.3 Ma and 60.2 ± 0.5 Ma, respectively. The 62 U-Pb analysis performed on 43 zircon grains using secondary ion mass spectrometry (SIMS) defined a discordant array in concordia space, spreading between an upper intercept of ~1915 Ma and a Late Paleocene lower intercept. The ~1915 Ma age for the majority of unshocked zircon grains from the impact melt rocks agrees with known geological events and zircon ages from the bedrock adjacent to Hiawatha Glacier [2], supporting a local origin for the samples. Of the 45 analyses performed on shocked zircon grains, the youngest nine data points are statistically indistinguishable, giving a robust concordia age and a weighted mean 206Pb/238U age of 57.99 ± 0.54 Ma (MSWD = 1.18; probability = 0.30; n = 9). We consider this to be the most robust estimate for the age of the impact structure [3]. Discussion: Impact melt rocks collected less than 10 km downstream from the edge of the Hiawatha structure contain unshocked zircon with ages matching that of the bedrock adjacent to Hiawatha Glacier. Shocked zircon in these samples gives a ~58 Ma U-Pb age, which agrees with the younger of two 40Ar/39Ar mini-plateau ages from the sand sample. The samples were thus derived from a Late Paleocene impact structure somewhere upstream but sufficiently proximal that the target geology is indistinguishable geochronologically from that exposed where the samples were recovered. Given existing geomorphic evidence for an eroded complex impact structure beneath Hiawatha Glacier, we suggest this is the source of the samples and thus that the Hiawatha structure is a relatively large impact structure that formed in the Late Paleocene. The new age indicates that the Hiawatha impact structure significantly predates Pleistocene glaciation and is unrelated to either the Paleocene-Eocene Thermal Maximum or flood basalt volcanism in east Greenland. The impact was contemporaneous with the Paleocene Carbon Isotope Maximum, although the impact's exact paleoenvironmental and climatic significance await further investigation. [ABSTRACT FROM AUTHOR]

Bardet-Biedl syndrome ( BBS) is an autosomal recessive multisystemic human genetic disorder characterized by six major defects including obesity, mental retardation, renal anomalies, polydactyly, retinal degeneration and hypogenitalism. In several cases of BBS, few other features such as metabolic defects, cardiovascular anomalies, speech deficits, hearing loss, hypertension, hepatic defects and high incidence of diabetes mellitus have been reported as well. The BBS displays extensive genetic heterogeneity. To date, 19 genes have been mapped on different chromosomes causing BBS phenotypes having varied mutational load of each BBS gene. In this review, we have discussed clinical spectrum and genetics of BBS. This report presents a concise overview of the current knowledge on clinical data and its molecular genetics progress upto date. [ABSTRACT FROM AUTHOR]

Although there has been significant research surrounding incidental findings (IFs), the guidelines and information provided to investigators remain unspecific, unclear, and often generalize the course of action to everyone in the field. We explored the perceptions and experiences of investigators regarding the return of IFs in genetic research. Researchers and clinician-researchers were invited to participate in semi-structured telephone interviews in Quebec and Ontario. Twenty professionals participated, and thematic analysis was used to analyze the transcriptions. Four contextual elements emerged: (i) degree of significance of results, (ii) respect for persons, (iii) infrastructure implications, and (iv) professional responsibilities. Our findings demonstrate that all investigators raised similar contextual elements surrounding the return of IFs. However, some nuances in participants' experiences of the understanding of professional responsibilities also emerged. Because of the existing nuances, a one-size-fits-all approach is inappropriate, suggesting that context ought to be considered in decisions about IFs. [ABSTRACT FROM AUTHOR]

Moslehi R, Signore C, Tamura D, Mills JL, DiGiovanna JJ, Tucker MA, Troendle J, Ueda T, Boyle J, Khan SG, Oh K-S, Goldstein AM, Kraemer KH. Adverse effects of trichothiodystrophy DNA repair and transcription gene disorder on human fetal development. The effects of DNA repair and transcription gene abnormalities in human pre-natal life have never been studied. Trichothiodystrophy (TTD) is a rare (affected frequency of 10−6) recessive disorder caused by mutations in genes involved in nucleotide excision repair (NER) pathway and in transcription. Based on our novel clinical observations, we conducted a genetic epidemiologic study to investigate gestational outcomes associated with TTD. We compared pregnancies resulting in TTD-affected offspring ( n = 24) with respect to abnormalities during their antenatal and neonatal periods to pregnancies resulting in their unaffected siblings ( n = 18), accounting for correlation, and to population reference values. Significantly higher incidence of several severe gestational complications was noted in TTD-affected pregnancies. Small for gestational age (SGA) <10th percentile [Relative risk (RR ) = 9.3, 95% CI = 1.4–60.5, p = 0.02], SGA <3rd percentile (RR = 7.2, 95% CI = 1.1–48.1, p = 0.04), and neonatal intensive care unit (NICU) hospitalization (RR = 6.4, 95% CI = 1.4–29.5, p = 0.02) occurred more frequently among TTD-affected neonates compared with their unaffected siblings. Compared with reference values from general obstetrical population, pregnancies that resulted in TTD-affected infants were significantly more likely to be complicated by hemolysis, elevated liver enzymes and low platelets (HELLP) syndrome (RR = 35.7, 95% CI = 7.6–92.5, p = 0.0002), elevated mid-trimester maternal serum human chorionic gonadotropin (hCG) levels (RR = 14.3, 95% CI = 7.0–16.6, p < 0.0001), SGA <3rd percentile (RR = 13.9, 95% CI = 7.4–21.1, p < 0.0001), pre-term delivery (<32 weeks) (RR = 12.0, 95% CI = 4.9–21.6, p < 0.0001), pre-eclampsia (RR = 4.0, 95% CI = 1.6–7.4, p = 0.006), and decreased fetal movement (RR = 3.3, 95% CI = 1.6–5.2, p = 0.0018). Abnormal placental development is an underlying mechanism that may explain the constellation of observed complications in our study. Thus, we hypothesize that TTD DNA repair and transcription genes play an important role in normal human placental development. [ABSTRACT FROM AUTHOR]

Autosomal recessive nonsyndromic hearing impairment (ARNSHI) segregating in three unrelated, large consanguineous Pakistani families (PKDF528, PKDF859 and PKDF326) is linked to markers on chromosome 12q14.2-q15. This novel locus is designated DFNB74. Maximum two-point limit of detection (LOD) scores of 5.6, 5.7 and 2.6 were estimated for markers D12 S313, D12 S83 and D12 S75 at θ = 0 for recessive deafness segregating in these three families. Haplotype analyses identified a critical linkage interval of 5.35 cM (5.36 Mb) defined by D12 S329 at 74.58 cM and D12 S313 at 79.93 cM. DFNB74 is the second ARNSHI locus mapped to chromosome 12, but the physical intervals do not overlap with one another. A locus contributing to the early onset, rapidly progressing hearing loss of A/J mice ( ahl4, age-related hearing loss 4) was reported to map to chromosome 10 in a region of conserved synteny to DFNB74, suggesting that ahl4 and DFNB74 may be due to mutations of the same gene in these two species. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented on mutations in the OTOA gene (MIM 607038) which causes autosomal recessive nonsyndromic hearing impairment.