Abstract
Commercial production of high-quality lumber for Nordic conifers is negatively impacted by long rotation age and adverse negative correlations between growth and wood quality traits. A ...prospective solution to ensure sufficient fibre quality from future plantations is to identify key wood traits for desired applications and to consider them in tree breeding programs. In this study, we used the widespread and largely reforested white spruce (Picea glauca Moench Voss) in Canada to investigate the genetic control of wood flexural properties such as stiffness, i.e. modulus of elasticity (MOE), and strength, i.e. modulus of rupture (MOR). We also looked at their phenotypic and genetic correlations with other wood quality and growth traits to assess the efficiency of indirect methods of selection to improve wood flexural properties in the context of multi-trait selection in tree breeding programs. To achieve this, standardized solid wood samples, growth records and standing tree wood quality traits were collected from 289 trees belonging to 38 white spruce families from a polycross genetic trial established on two different sites in the province of Quebec, Canada. Flexural stiffness and strength, height, diameter at breast height (DBH) and wood density showed moderate to high heritability. Flexural stiffness was also positively correlated at the genetic level with flexural strength, average wood density and acoustic velocity as an indirect measure of dynamic MOE (${r}_{\mathrm{G}}$ = 0.99, ${r}_{\mathrm{G}}$ = 0.78 and ${r}_{\mathrm{G}}$= 0.78, respectively). When selecting the top 5 per cent of the trees, the expected genetic gains varied from 3.6 per cent for acoustic velocity to 16.5 per cent for MOE. Selection based on wood density and acoustic velocity would result in considerable genetic gains in flexural stiffness. Several multi-trait selection scenarios were tested to investigate the genetic gains obtained from selecting with different combinations of growth and wood quality traits. The results showed that indirect selection for wood flexural properties by means of acoustic velocity and wood density are efficient methods that can be combined in operational white spruce breeding programs to increase simultaneously genetic gains for growth and wood flexural properties.
Premise of the study: The genetic structure of jack pine (Pinus banksiana Lamb.), a North American boreal conifer with large longitudinal distribution, was investigated to test for the possible ...existence of a genetically distinct lineage in the Maritimes region in northeastern North America, which could be indicative of a mid-latitude coastal refuge during the last glaciation. METHODS: One maternally inherited mitochondrial DNA (mtDNA) minisatellite marker and four paternally inherited chloroplast DNA (cpDNA) microsatellite markers were used to assess the range-wide geographical structure of jack pine populations with particular focus on northeastern North America. Key results: The populations from the Maritimes region presented a unique mtDNA background characterized by very low diversity and the preponderance of a distinctive mitotype. The distribution of cpDNA diversity was not spatially structured, though three chlorotypes were restricted to the east. CONCLUSIONS: MtDNA data suggest that populations from the Maritimes region derive from a genetically depauperated north-coastal refugium. Contrastingly, the much higher geographical uniformity observed for cpDNA variation indicates that gene flow by pollen had been much more effective than seed gene flow at homogenizing population structure.
Summary
Over the last decade, extensive genetic and genomic resources have been developed for the conifer white spruce (Picea glauca, Pinaceae), which has one of the largest plant genomes (20 Gbp). ...Draft genome sequences of white spruce and other conifers have recently been produced, but dense genetic maps are needed to comprehend genome macrostructure, delineate regions involved in quantitative traits, complement functional genomic investigations, and assist the assembly of fragmented genomic sequences. A greatly expanded P. glauca composite linkage map was generated from a set of 1976 full‐sib progeny, with the positioning of 8793 expressed genes. Regions with significant low or high gene density were identified. Gene family members tended to be mapped on the same chromosomes, with tandemly arrayed genes significantly biased towards specific functional classes. The map was integrated with transcriptome data surveyed across eight tissues. In total, 69 clusters of co‐expressed and co‐localising genes were identified. A high level of synteny was found with pine genetic maps, which should facilitate the transfer of structural information in the Pinaceae. Although the current white spruce genome sequence remains highly fragmented, dozens of scaffolds encompassing more than one mapped gene were identified. From these, the relationship between genetic and physical distances was examined and the genome‐wide recombination rate was found to be much smaller than most estimates reported for angiosperm genomes. This gene linkage map shall assist the large‐scale assembly of the next‐generation white spruce genome sequence and provide a reference resource for the conifer genomics community.
Significance Statement
Conifers have very large genomes whose macrostructure is still poorly understood. Here we developed a greatly expanded reference genetic map for white spruce. Gene marker density and accuracy of this map are high, synteny with pine genetic maps is high and segregating regions underlying quantitative trait variation were well populated with genes. Genome sequence scaffolds and transcriptome information were anchored on the genetic map, thus providing a highly relevant resource for future conifer genome research.
Background
The aim was to study the association between allergic multimorbidity and adult‐onset asthma considering the number of allergic diseases and the age effect.
Methods
We used population‐based ...data from Finnish national registers including 1205 adults over 30 years of age with recently diagnosed asthma (age range: 30‐93), matched for gender, age, and living region with one or two controls (n = 2050). Allergic rhinitis (AR), allergic conjunctivitis (AC), and allergic dermatitis (AD) were defined from self‐completed questionnaire. Conditional logistic regression adjusted on potential confounders (smoking, growing in countryside, childhood hospitalized infection/pneumonia, parental asthma/allergy, parental smoking, education level, professional training, number of siblings, and birth order) was applied to estimate the asthma risk associated with allergic multimorbidity.
Results
A total of 1118 cases with asthma and 1772 matched controls were included mean (SD, min‐max) 53 (11, 31‐71) years, 37% men). AR, AC, and AD were reported by 50.2%, 39.6%, and 33.8%, respectively, among subjects with asthma and 26.1%, 20.0%, and 23.5%, respectively, among controls. Compared to nonatopics, adult‐onset asthma increased with the number of allergic diseases; adjusted OR for asthma 95% CI associated with 1, 2, and 3 allergic diseases was 1.95 1.52‐2.49, 2.87 2.19‐3.77, and 4.26 3.07‐5.90, respectively. The association between adult‐onset asthma and ≥ 1 allergic multimorbidity decreased with increasing age (3.52 2.51‐4.94, 2.44 1.74‐3.42, and 1.68 1.04‐2.71) in subjects < 50 years, 50‐62 years, and > 62 years, respectively (p for age*≥1 allergic multimorbidity interaction, 0.002).
Conclusions
Adult‐onset asthma was positively associated with the number of allergic diseases, and this association decreases with age.
A population‐based matched case‐control study of adult‐onset asthma was performed in Finland. The odds ratio for asthma increased with the number of allergic diseases, and the association between ≥ 1 allergic disease and asthma decreased with age. 3 allergic diseases were reported by 27.5%, 12.3%, and 6.6% asthmatic patients in the age groups <= 49, 50‐62, and >= 63 years old, respectively, while in control groups, only 8.5%, 5.0%, and 5.5% subjects reported three allergic diseases.
Background
Frail older persons may have an atypical presentation of coronavirus disease 2019 (COVID-19). The value of real-time reverse-transcriptase polymerase chain reaction (rRT-PCR) testing for ...identifying severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nursing homes (NHs) residents is not known.
Objective
To determine whether (i) atypical symptoms may predict rRT-PCR results and (ii) rRT-PCR results may predict immunisation against SARS-CoV-2 in NH residents.
Design
A retrospective longitudinal study.
Setting
Eight NHs with at least 10 rRT-PCR-positive residents.
Subjects
A total of 456 residents.
Methods
Typical and atypical symptoms recorded in residents’ files during the 14 days before and after rRT-PCR testing were analysed. Residents underwent blood testing for IgG-SARS-CoV-2 nucleocapsid protein 6 to 8 weeks after testing. Univariate and multivariate analyses compared symptoms and immunisation rates in rRT-PCR-positive and negative residents.
Results
A total of 161 residents had a positive rRT-PCR (35.3%), 17.4% of whom were asymptomatic before testing. Temperature >37.8°C, oxygen saturation <90%, unexplained anorexia, behavioural change, exhaustion, malaise and falls before testing were independent predictors of a further positive rRT-PCR. Among the rRT-PCR-positive residents, 95.2% developed SARS-CoV-2 antibodies vs 7.6% in the rRT-PCR-negative residents. Among the residents with a negative rRT-PCR, those who developed SARS-CoV-2 antibodies more often had typical or atypical symptoms (P = 0.02 and <0.01, respectively).
Conclusion
This study supports a strategy based on (i) testing residents with typical or unexplained atypical symptoms for an early identification of the first SARS-CoV-2 cases, (ii) rT-PCR testing for identifying COVID-19 residents, (iii) repeated wide-facility testing (including asymptomatic cases) as soon as a resident is tested positive for SARS-CoV-2 and (iv) implementing SARS-CoV-2 infection control measures in rRT-PCR-negative residents when they have unexplained typical or atypical symptoms.
To evaluate the performance of underwater acoustic communication systems, it is typically assumed that the noise at the receiver is uncorrelated spatially and temporally. This assumption ...underestimates the impact of acoustic ocean ambient noise on the performance of communication systems. In this article, the impact of ocean ambient noise on a coherent acoustic communication system is analyzed. The communication performance is assessed in narrowband conditions at a center frequency of <inline-formula><tex-math notation="LaTeX">{\text{2.048}\;\text{kHz}}</tex-math></inline-formula> using the noise measurements from two different experiments-DalComm1 and the shallow water Canada Basin acoustic propagation experiment (SW CANAPE). DalComm1 focuses on characterizing the acoustic channel over ranges of 1-10 km on the Nova Scotian littoral, while the spatio-temporal variability of noise propagation in shallow and deep water environments was characterized during the CANAPE experiments. The ambient noise coherence and directionality in both environments were also measured. Two distinct noise modeling methodologies are presented to represent realistic synthetic ambient noise with defined directionality. Further, the synthetic noise is validated against measured ambient noise. The impact of ambient noise characteristics on an optimum space-time filter is characterized. A frame structure with an optimum training duration is also defined for the adaptive filter. It is observed that the bit-error rate of the space-time filter depends on optimizing the training and payload duration in the received signal.
Conifers have dominated forests for more than 200 million years and are of huge ecological and economic importance. Here we present the draft assembly of the 20-gigabase genome of Norway spruce ...(Picea abies), the first available for any gymnosperm. The number of well-supported genes (28,354) is similar to the >100 times smaller genome of Arabidopsis thaliana, and there is no evidence of a recent whole-genome duplication in the gymnosperm lineage. Instead, the large genome size seems to result from the slow and steady accumulation of a diverse set of long-terminal repeat transposable elements, possibly owing to the lack of an efficient elimination mechanism. Comparative sequencing of Pinus sylvestris, Abies sibirica, Juniperus communis, Taxus baccata and Gnetum gnemon reveals that the transposable element diversity is shared among extant conifers. Expression of 24-nucleotide small RNAs, previously implicated in transposable element silencing, is tissue-specific and much lower than in other plants. We further identify numerous long (>10,000 base pairs) introns, gene-like fragments, uncharacterized long non-coding RNAs and short RNAs. This opens up new genomic avenues for conifer forestry and breeding.
To highlight how using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach to understand the certainty in the evidence about the impact of climate change in ...health outcomes increases transparency. Also, how GRADE can enhance communication and decisions about adaptation and mitigation strategies.
We developed a narrative review based on an assessment of exiting systematic reviews addressing the effect of climate change on health outcomes and the impact of mitigation and adaptation strategies.
Adopting structured approaches such as GRADE to tackle the impact of climate change on health may help to (1) define the specific question to be addressed; (2) summarize the evidence in a structured way and assess uncertainty; (3) provide a systematic framework to move from evidence to action and to offer recommendations of different strength; (4) provide a systematic way to adapt recommendations to specific settings; and (5) provide a framework to assess the certainty of modeled evidence.
In this article, we describe epidemiologic principles that could be used to move decision-making in climate change forward.
•Reviews´ authors in climate change are often unaware of structured approaches to assess evidence.•This article describes a proposal focused on using the GRADE approach on climate change.•The GRADE approach has been used successfully in other prominent public health problems.
This article presents a design-for-test (DFT) loopback scheme for testing the analog portion of a mixed-signal chip using an all- digital tester. In fact, the proposed approach is used to assess the ...ENOB of a high-speed 6-bit ADC without the need for an external signal generator. Using an on-chip PLL with a programmable divider, a divided version of the 16GHz clock is passed through an on-chip buffer network where the output driver amplitude is programmable to achieve the desired fill ratio (~80%). The test PLL is coherent to the system PLL as they are driven from the same reference clock; hence, no windowing needs to be applied to the ADC output prior to performing the FFT for ENOB assessment. The on-chip output driver has an open-drain configuration that is far- end terminated through 50Ω pull-up resistors connected to a 2.0V external supply on the device interface board (DIB). The output is then applied to a 5th order external filter on the DIB with a 3dB cutoff frequency of 2.4GHz to filter out the high order harmonics prior to looping back the stimulus to the ADC front-end. The proposed scheme is implemented within a CMOS 32nm ADC macro and is experimentally validated using a commercial all-digital automated-test-equipment (ATE). A 4.5 bit ENOB was experimentally measured using the ADC under test. Unlike conventional loopback schemes, the proposed architecture is not susceptible to fault masking.
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