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Northern sand lance (Ammodytes dubius) are essential forage fish in most offshore, temperate-to-polar waters on the Northwest Atlantic shelf (NWA), but their population structure and genetic separation from the American sand lance (A. americanus) remain unresolved. We assembled a reference genome for A. dubius (first in the Ammodytidae) and then used low-coverage whole genome sequencing on 262 specimens collected across the species distribution (Mid-Atlantic Bight to Greenland) to quantify genetic differentiation between geographic regions based on single nucleotide polymorphisms. We found strong separation between A. dubius from locations north and south of the Scotian Shelf, largely due to massive genetic differentiation spanning most of chromosomes 21 and 24. Genetic distance increased with geographic distance in the smaller southern cluster but not in the larger northern cluster, where genetic homogeneity appeared across large geographic distances (>103 km). The two genetic clusters coincide with a clear break in winter sea surface temperature, suggesting that differential offspring survival, rather than limited transport, causes a break in realized connectivity. Nuclear and mitochondrial DNA both clearly delineated A. dubius from A. americanus , thereby confirming a species boundary through spatial niche partitioning into inshore (A. americanus) and offshore (A. dubius) sand lance species on the NWA. [ABSTRACT FROM AUTHOR]

Northern sand lance (Ammodytes dubius) are essential forage fish in most offshore, temperate-to-polar waters on the Northwest Atlantic shelf (NWA), but their population structure and genetic separation from the American sand lance (A. americanus) remain unresolved. We assembled a reference genome for A. dubius (first in the Ammodytidae) and then used low-coverage whole genome sequencing on 262 specimens collected across the species distribution (Mid-Atlantic Bight to Greenland) to quantify genetic differentiation between geographic regions based on single nucleotide polymorphisms. We found strong separation between A. dubius from locations north and south of the Scotian Shelf, largely due to massive genetic differentiation spanning most of chromosomes 21 and 24. Genetic distance increased with geographic distance in the smaller southern cluster but not in the larger northern cluster, where genetic homogeneity appeared across large geographic distances (>103 km). The two genetic clusters coincide with a clear break in winter sea surface temperature, suggesting that differential offspring survival, rather than limited transport, causes a break in realized connectivity. Nuclear and mitochondrial DNA both clearly delineated A. dubius from A. americanus , thereby confirming a species boundary through spatial niche partitioning into inshore (A. americanus) and offshore (A. dubius) sand lance species on the NWA. [ABSTRACT FROM AUTHOR]

Selection can create complex patterns of adaptive differentiation among populations in the wild that may be relevant to management. Atlantic cod in the Northwest Atlantic are at a fraction of their historical abundance and a lack of recovery within the Gulf of Maine has created concern regarding the misalignment of fisheries management structures with biological population structure. To address this and investigate genome‐wide patterns of variation, we used low‐coverage sequencing to perform a region‐wide, whole‐genome analysis of fine‐scale population structure. We sequenced 306 individuals from 20 sampling locations in U.S. and Canadian waters, including the major spawning aggregations in the Gulf of Maine in addition to spawning aggregations from Georges Bank, southern New England, the eastern Scotian Shelf, and St. Pierre Bank. With genotype likelihoods estimated at almost 11 million loci, we found large differences in haplotype frequencies of previously described chromosomal inversions between Canadian and U.S. sampling locations and also among U.S. sampling locations. Our whole‐genome resolution also revealed novel outlier peaks, some of which showed significant genetic differentiation among sampling locations. Comparisons between allochronic winter‐ and spring‐spawning populations revealed highly elevated relative (FST) and absolute (dxy) genetic differentiation near genes involved in reproduction, particularly genes associated with the brain‐pituitary‐gonadal axis, which likely control timing of spawning, contributing to prezygotic isolation. We also found genetic differentiation associated with heat shock proteins and other genes of functional relevance, with complex patterns that may point to multifaceted selection pressures and local adaptation among spawning populations. We provide a high‐resolution picture of U.S. Atlantic cod population structure, revealing greater complexity than is currently recognized in management. Our genome‐scan approach likely underestimates the full suite of adaptive differentiation among sampling locations. Nevertheless, it should inform the revision of stock boundaries to preserve adaptive genetic diversity and evolutionary potential of cod populations. [ABSTRACT FROM AUTHOR]

Abstract: A broadband multilayer beam‐steering antenna array with a modified mushroom‐like radiating element is introduced. The two‐layer aperture‐coupled array consists of four equal sets of mushroom‐like elements, each of which is made of 16 unit cells in a 4 × 4 configuration. The feeding network is a modified quasi‐Butler matrix, which benefits from improved double‐box branch line couplers. The network has an isolation bandwidth between 4 and 7.9 GHz (65%) and a transmission bandwidth from 4.8 to 7.1 GHz (39%), which operates acceptably in most of the C‐band, especially at wireless local area network and Intelligent Transport Systems (ITS). A broadband Butler matrix uses broadband 3 dB couplers and a middle network. The geometry of the element and feeding network is utilized in array form to enhance the impedance bandwidth and radiation efficiency of the antenna. The results show that the antenna impedance bandwidth covers 3.82 to 8.2 GHz (port 1) and 3.8 to 8.28 GHz (port 2) for Snn ≤ −10 dB, which covers the C‐band fully (4–8 GHz). Moreover, it has a 3 dB gain‐bandwidth of 2.25 GHz that extends from 4.65 to 6.9 GHz with a peak value of 13.65 dBi. The antenna array has a 3 dB axial ratio bandwidth of 1.65 GHz that extends from 4.9 to 6.55 GHz and involves wireless local area network (5.15–5.825 GHz) and ITS (5.795–6.400 GHz). The radiation efficiency of the array for both port excitations is in excess of 75% when circular polarization is achieved. Two firing beams at elevation angles of 20° and −35° are obtained for ports 1 and 2 upon excitation, respectively. [ABSTRACT FROM AUTHOR]

In this letter, a compact size multiband metamaterial based antenna with circular polarization property is presented. A metamaterial unit cell consist of four thin strips that constitute the modified square split ring resonator (MSSRR) which each of strips generate negative refraction index in antenna's resonant frequency modes. The proposed antenna operate at Bluetooth (2400-2484 MHz specified by IEEE 802.11b/g), WiMAX (3.3-3.6 GHz specified by IEEE 802.16) and C-band (4-8 GHz) while circular polarization feature is obtained at these operational bands. The total size of antenna is 20 × 20 × 1.5 mm and realized on FR4-epoxy substrate. The design concept was confirmed by fabrication of the antenna scheme and measuring its characteristics. The extracted results show the antenna exhibits good agreement with simulation ones. [ABSTRACT FROM AUTHOR]

Background: Impairment of gas and substrate exchange through the placenta leads to fetal hypoxia and growth restriction. Oxygenation of vital organs is maintained with preferential perfusion at the expense of less vital organs, challenging the fetal cardiovascular system. Objectives: To identify cardiovascular compromise in preterm small for gestational age (SGA) infants using the cardiac biomarker B-type natriuretic peptide (BNP), which indicates the workload of the myocardium. Methods: In this retrospective case-control study, 26 SGA infants born at less than 32 weeks of gestation from October 2009 to October 2010 were matched for gestational age and month of birth with 26 appropriate for gestational age (AGA) infants. Antenatal Doppler ultrasound was used to identify fetal hemodynamic changes by determination of the pulsatility index (PI) of the middle cerebral artery (MCA-PI), umbilical artery (UA-PI) and veins of the ductus venosus (DV-PIV). These indices were compared with BNP levels obtained within 6 h after birth. Results: Antenatal PIs of MCA, UA and DV were significantly related to elevated BNP levels after birth in SGA infants, but not in AGA infants (SGA: MCA-PI = r2 0.23, p < 0.05; UA-PI = r2 0.46, p < 0.01; DV-PIV = r2 0.31, p < 0.05). Furthermore, signs of perinatal (chronic) asphyxia coincided with elevated levels of BNP. SGA was related to more postnatal cardiocirculatory complications. No significant relations between postnatal cardiac ultrasound measurements, placenta size and BNP were found. Conclusion: BNP levels were elevated early after birth in SGA infants and corresponded positively with Doppler indices of circulatory compromise. This suggests an increased workload of the myocardium. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

ABSTRACT Objectives To test the fetal profile (FP) line, defined as the line that passes through the anterior border of the mandible and the nasion, as a reference line for forehead and mandible anomalies. Methods Volumes of 248 normal and 24 pathological fetuses (16-36 and 19-37 weeks' gestation, respectively) were analysed retrospectively. When the FP line passes anteriorly, across or posteriorly to the frontal bone, this was defined as 'negative', 'zero' or 'positive', respectively. When the FP line was positive the distance ( F distance) between the FP line and the frontal bone was measured. Results No cases with a negative FP line were found in the normal fetuses. Before 27 weeks' gestation the FP line was always 'zero' except in one case. After 27 weeks' gestation the FP line was 'positive' in up to 25% ( F distance (mean, range): 2.8, 2.1-3.6 mm). The FP line correctly identified 13 cases with retrognathia, 5 cases with frontal bossing and 3 cases with a sloping forehead. Conclusion Although large prospective studies are needed, the FP line may be a useful tool to detect second trimester profile anomalies such as retrognathia, sloping forehead and frontal bossing with the possibility of quantifying the latter. © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The objective of this study was to examine the factors influencing fieldwork educators' ability and willingness to supervise Level II occupational therapy students in hospital-based settings. Qualitative focus groups were used to explore the perceptions of occupational therapists in four urban hospitals in Nebraska. The study presents the issues facing fieldwork supervisors and their suggestions on how to improve the fieldwork process. Both personal and professional factors influenced occupational therapists' willingness to accept students, while facility constraints were the primary reason occupational therapists would not accept Level II students. Fieldwork educators believe that their facilities need structured fieldwork programs and that students need more formalized fieldwork preparation at their academic institutions. Themes highlight the need for continued collaborative endeavors between academic fieldwork coordinators and fieldwork educators. [ABSTRACT FROM AUTHOR]

Decompressive craniectomy is an important method for managing refractory intracranial hypertension in patients with head injury. We reviewed a large series of patients who underwent this surgical procedure to establish the incidence and type of postoperative complications. From 1998 to 2005, decompressive craniectomy was performed in 108 patients who suffered from a closed head injury. The incidence rates of complications secondary to decompressive craniectomy and risk factors for developing these complications were analysed. In addition, the relationship between outcome and clinical factors was analysed. Twenty-five of the 108 patients died within the first month after surgical decompression. A lower GCS at admission seemed to be associated with a poorer outcome. Complications related to surgical decompression occurred in 54 of the 108 (50%) patients; of these, 28 (25.9%) patients developed more than one type of complication. Herniation through the cranial defect was the most frequent complication within 1 week and 1 month, and subdural effusion was another frequent complication during this period. After 1 month, the “syndrome of the trephined” and hydrocephalus were the most frequent complications. Older patients and/or those with more severe head trauma had a higher occurrence rate of complications. The potential benefits of decompressive craniectomy can be adversely affected by the occurrence of complications. Each complication secondary to surgical decompression had its own typical time window for occurrence. In addition, the severity of head injury was related to the development of a complication. [ABSTRACT FROM AUTHOR]

Objective: To investigate parents' opinions about enrolling their premature baby into several research studies in the few days after birth. Methodology: A questionnaire was given to parents of premature babies in the neonatal intensive core unit who had been invited to loin several studies (two to seven). Results: Alt 50 mothers and 42 of 48 fathers completed the questionnaire independently; 28% had been asked to join two studies, 32% three, 24% four, 14% five, and 2% six studies. There were 61 babies with mean (SD) geslational age 26.9 (1.6) weeks and birth weight 877(249) g. Nearly three quarters (71%) of the parents thought it was very good for their baby to be in a hospital that was carrying out a lot of research. Most (93%) thought that their baby would get the same or better care in a study. Only 15% thought their baby was too small for research studies. Almost all (98%) wanted to be involved in the decision about their baby joining a study. Only 22% were worried about the number of studies; 10% would not enrol their baby in any studies, but 74% were willing for their baby to join two or more studies, and 10% would enrol in all the studies. Most (94%) believed that their baby's participation would improve care of future babies. Conclusions: Most of these parents were willing to loin several studies. The majority were not worried about their baby participating in the studies. The profession needs to be aware that parents are supportive of neonatal research and participation in multiple studies. [ABSTRACT FROM AUTHOR]

In the general circular permutation layout problem there are two concentric circles, C and C. There are a set of n inner terminals on C and a set of n outer terminals on C: terminals i on C and π on C are to be connected by means of a wire, where 1 ≤ i ≤ n. All wires must be realized in the interior of C. Each wire can intersect C at most once and at most K wires, for a fixed K, can pass between two adjacent inner terminals. A linear-time algorithm for obtaining a planar homotopy (single-layer realization) of an arbitrary instance of the general circular permutation layout problem, for K ≥ 0, is proposed. Previously, K = 1 has been studied. In this paper the algorithm is also extended to a more general problem, in which the number of wires allowed to pass between each pair of adjacent terminals on C may be different from pair to pair. [ABSTRACT FROM AUTHOR]

Consider a weighted transitive graph, where each vertex is assigned a positive weight. Given a positive integer k, the maximum k-covering problem is to find k disjoint cliques covering a set of vertices with maximum total weight. An 0( kn)-time algorithm to solve the problem in a transitive graph is proposed, where n is the number of vertices. Based on the proposed algorithm the weighted version of a number of problems in VLSI layout (e.g., k-layer topological via minimization), computational geometry (e.g., maximum multidimensional k-chain), graph theory (e.g., maximum k-independent set in interval graphs), and sequence manipulation (e.g., maximum increasing k-subsequence) can be solved in O(kn), where n is the input size. [ABSTRACT FROM AUTHOR]

This article reports on the development of an adult sickle cell support group and provides a description of the psychosocial factors most prevalent in patients' lives. Sickle cell disease refers to a variety of inherited disorders called hemoglobinopathies, which involve the production of abnormal red blood cells. Sickle cell disease exists in all races and in all parts of the world. No cure for sickle cell disease exists, and medical intervention is generally palliative, capable only of temporarily alleviating pain. The author has described the process by which a community-based adult sickle cell group developed through three overlapping stages and functions: patient education, task-oriented activities, and ongoing support. Research regarding mental health problems of sickle cell patients indicates a prevalence of mental disorders that exceeds that of the general population. age adults. Through this group, the physician-patient relationship was improved, patients were able to express many unspoken fears, and individual members were able to seek help.