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The pandemic of coronavirus disease 2019 (COVID-19) has posed serious challenges. It is vitally important to further clarify the epidemiological characteristics of the COVID-19 outbreak for future study and prevention and control measures. Epidemiological characteristics and spatial−temporal analysis were performed based on COVID-19 cases from 21 January 2020 to 1 March 2020 in Shandong Province, and close contacts were traced to construct transmission chains. A total of 758 laboratory-confirmed cases were reported in Shandong. The sex ratio was 1.27: 1 (M: F) and the median age was 42 (interquartile range: 32–55). The high-risk clusters were identified in the central, eastern and southern regions of Shandong from 25 January 2020 to 10 February 2020. We rebuilt 54 transmission chains involving 209 cases, of which 52.2% were family clusters, and three widespread infection chains were elaborated, occurring in Jining, Zaozhuang and Liaocheng, respectively. The geographical and temporal disparity may alert public health agencies to implement specific measures in regions with different risk, and should attach importance on how to avoid household and community transmission.
Previous work led to the proposal that the precision feeding of a high-concentrate diet may represent a potential method with which to enhance feed efficiency (FE) when rearing dairy heifers. However, the physiological and metabolic mechanisms underlying this approach remain unclear. This study used metabolomics analysis to investigate the changes in plasma metabolites of heifers precision-fed diets containing a wide range of forage to concentrate ratios. Twenty-four half-sib Holstein heifers, with a similar body condition, were randomly assigned into four groups and precision fed with diets containing different proportions of concentrate (20%, 40%, 60% and 80% based on DM). After 28 days of feeding, blood samples were collected 6 h after morning feeding and gas chromatography time-of-ﬂight/MS was used to analyze the plasma samples. Parameters of oxidative status were also determined in the plasma. The FE (after being corrected for gut fill) increased linearly (P < 0.01) with increasing level of dietary concentrate. Significant changes were identified for 38 different metabolites in the plasma of heifers fed different dietary forage to concentrate ratios. The main pathways showing alterations were clustered into those relating to carbohydrate and amino acid metabolism; all of which have been previously associated with FE changes in ruminants. Heifers fed with a high-concentrate diet had higher (P < 0.01) plasma total antioxidant capacity and superoxide dismutase but lower (P ≤ 0.02) hydroxyl radical and hydrogen peroxide than heifers fed with a low-concentrate diet, which might indicate a lower plasma oxidative status in the heifers fed a high-concentrate diet. Thus, heifers fed with a high-concentrate diet had higher FE and antioxidant capacity but a lower plasma oxidative status as well as changed carbohydrate and amino acid metabolism. Our findings provide a better understanding of how forage to concentrate ratios affect FE and metabolism in the precision-fed growing heifers.
Porphyromonas gingivalis has been linked to the development and progression of oesophageal squamous cell carcinoma (ESCC), and is considered to be a high-risk factor for ESCC. Currently, the commonly used methods for P. gingivalis detection are culture or DNA extraction-based, which are either time and labour intensive especially for high-throughput applications. We aimed to establish and evaluate a rapid and sensitive direct quantitative polymerase chain reaction (qPCR) protocol for the detection of P. gingivalis without DNA extraction which is suitable for large-scale epidemiological studies. Paired gingival swab samples from 192 subjects undergoing general medical examinations were analysed using two direct and one extraction-based qPCR assays for P. gingivalis. Tris-EDTA buffer-based direct qPCR (TE-direct qPCR), lysis-based direct qPCR (lysis-direct qPCR) and DNA extraction-based qPCR (kit-qPCR) were used, respectively, in 192, 132 and 60 of these samples for quantification of P. gingivalis. The sensitivity and specificity of TE-direct qPCR was 95.24% and 100% compared with lysis-direct qPCR, which was 100% and 97.30% when compared with kit-qPCR; TE-direct qPCR had an almost perfect agreement with lysis-direct qPCR (κ = 0.954) and kit-qPCR (κ = 0.965). Moreover, the assay time used for TE-direct qPCR was 1.5 h. In conclusion, the TE-direct qPCR assay is a simple and efficient method for the quantification of oral P. gingivalis and showed high sensitivity and specificity compared with routine qPCR.
A 2-year fertilization experiment was conducted to study the effect of different ratios of organic (pig) manure on wheat yield and nitrogen use efficiency (NUE). The four treatments were no nitrogen (N) (CK); 100% chemical fertilizer N (urea; T1); 70% chemical fertilizer N + 30% organic manure N (T2) and 50% chemical fertilizer N + 50% organic manure N (T3), with the same amount of applied nitrogen (120 kg/ha). The results showed the maximum grain yield (3049 kg/ha), crop nitrogen uptake (216 kg/ha), NUE (65.4%) and accumulated nitrate nitrogen (NO3−-N in 0–200 cm, 142 kg/ha) were observed in the T1 among all treatments in the first year. However, the largest grain yield (5074 kg/ha), crop nitrogen uptake (244 kg/ha) and NUE (82.5%) were under T2 treatment in the second year. Furthermore, T2 had the maximum NO3−-N content in 0–100 cm layer (116 kg/ha), especially 0–40 cm layer, and the lowest NO3−-N content in 100–200 cm (58.8 kg/ha). However, 50% organic manure N in T3 increased apparent nitrogen loss by 39.0% compared to that in T2. Therefore, 30% organic manure N application was more conducive for enhancing wheat yield and NUE and promoting environmental safety after 1-year fertilization time.
There are strong links between circadian disturbance and some of the most characteristic symptoms of clinical major depressive disorder (MDD). However there are no published studies of changes in expression of clock genes or of other neuropeptides related to circadian-rhythm regulation, which may influence recurrent susceptibility after treatment with antidepressant in MDD.
Blood samples were collected from twelve healthy controls and twelve male major depressive patients pre- and post- treated with escitalopram for eight weeks at 4-hour intervals for 24 hours. Outcome measures were the relative expression of mRNA of clock genes (hPERIOD1, hPERIOD2, hPERIOD3, hCRY1, hBMAL1, hNPAS2 and hGSK-3beta) and the levels of serum melatonin, Vasoactive Intestinal Peptide (VIP), cortisol, Adrenocorticotropic Hormone (ACTH), Insulin-like Growth Factor-1(IGF-1) and growth hormone (GH) in twelve healthy controls and twelve pre- and post- treated MDD patients.
Compared with healthy controls, MDD patients showed disruptions in diurnal rhythms of expression of hPERIOD1, hPERIOD2, hCRY1, hBMAL1, hNPAS2 and hGSK-3beta, along with disruptions in diurnal rhythms of release of melatonin, VIP, cortisol, ACTH, IGF-1, and GH. Several of these disruptions (hPER1, hCRY1, melatonin, VIP, cortisol, ACTH, and IGF-1) persisted after eight weeks escitalopram treatment, as did elevation of 24-hour levels of VIP and decreases in 24-hour levels of cortisol and ACTH.
These persisted neurobiological changes may play a role in MDD symptoms that are thought to contribute to recurrence vulnerability and in maintenance therapy for a long term.
The implementation of advanced multi-level modulation schemes such as quadrature phase-shift keying (QPSK) in contrast to the conventional on–off keying is crucial to further boost the terahertz (THz) communications speed. Thereby, carrier phase noise reduction in the THz range is one of the key goals that need to be urgently achieved. In this paper, the photonic-based THz sources and the phase noise problem are briefly summarized. Then, a low phase-noise photonic source based on the stimulated Brillouin scattering (SBS) optical fiber cavity is first applied for a 300-GHz-band QPSK wireless communication link. The highest data rate at forward-error-correction limited condition was 15 Gbaud utilizing the SBS-based photonic source with a small transmit power of ~ −36 dBm. Its transmission characteristics are evaluated and compared with the conventional optical frequency comb generator (OFCG)-based source at 5 Gbaud. The proposed SBS-based photonic source has been proven to offer better performances than the OFCG-based source with respect to the phase noise, optical carrier to noise ratio, and bit error rate in communications.
Pedophilia is a disorder where sexual preferences of adults are directed towards children. This disorder impacts society with 1–2 out of every 10 children being sexually approached by an adult, often resulting in prolonged negative psychological effects. Prior research reported structural and functional amygdala alterations in pedophilia. As the neurophenomenological model of sexual arousal suggests the importance of the amygdala in the emotional component, we focused on amygdala functional connectivity in pedophilia.
To investigate amygdala functional connectivity (FC) modulated by expectancy and salient stimuli in pedophilic patients.
Thirteen pedophilic patients and 13 matched healthy controls underwent a salience expectancy task in a 7T ultra high fMRI study. Subjects perceived pictures of naked adults and children. Half of the pictures were preceded by an expectancy cue. Participants were instructed to actively expect the picture depending on the cue. We conducted psychophysiological analysis (PPI) to examine amygdala FC changes in two amygdala sub-regions for child/adult stimuli during the expectancy period and the visual stimuli consummation period using as seed regions the basolateral (BLA) and central nucleus of the amygdala (CeA).
Healthy controls, relative to patients showed significant stronger left CeA to right post-central gyrus FC during expectancy of adult > child picture. For picture condition (adult > child picture) we found significant stronger left CeA to left dorsolateral prefrontal cortex FC in patients compared to healthy controls.
These findings add to the recent literature by indicating that amygdala dysfunctional connectivity is involved in development of deviant sexual behavior.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
As an epigenetic modification, DNA methylation may reflect the interaction between genetic and environmental factors in the development of schizophrenia (SCZ). Catechol-O-methyltransferase (COMT) gene is a promising candidate gene of SCZ. In the present study, we investigate the association of COMT methylation with the risk of SCZ using bisulfite pyrosequencing technology. Significant association between DNA methylation of COMT and the risk of SCZ is identified (P = 1.618e−007). A breakdown analysis by gender shows that the significance is driven by males (P = 3.310e−009), but not by females. DNA methylation of COMT is not significantly associated with SCZ clinical phenotypes, including p300 and cysteine level. No interaction is found between COMT genotypes and the percent methylation of this gene. Receiver operating characteristic (ROC) curve shows that DNA methylation of COMT is able to predict the SCZ risk in males (area under curve [AUC] = 0.802, P = 1.91e−007). The current study indicates the clinical value of COMT methylation as a potential male-specific biomarker in SCZ diagnosis.
The development of digestive organs and the establishment of gut microbiota in pullets play an important role throughout life. This study was conducted to investigate the effects of Bacillus subtilis (BS) on growth performance, intestinal function and gut microbiota in pullets from 0 to 6 weeks of age. Hy-line Brown laying hens (1-day-old, n = 504) were randomly allotted into four diets with a 2 × 2 factorial design: (1) basal diet group (control); (2) antibiotics group (AGP), the basal diet supplemented with 20 mg/kg Bacitracin Zinc and 4 mg/kg Colistin Sulphate; (3) BS group, the basal diet supplemented with 500 mg/kg BS and (4) mixed group, the basal diet supplemented with both AGP and BS. As a result, when BS was considered the main effect, BS addition (1) reduced the feed conversion ratio at 4 to 6 weeks (P < 0.05); (2) decreased duodenal and jejunal crypt depth at 3 weeks; (3) increased the villus height : crypt depth (V : C) ratio in the duodenum at 3 weeks and jejunal villus height at 6 weeks and (4) increased sucrase mRNA expression in the duodenum at 3 weeks as well as the jejunum at 6 weeks, and jejunal maltase and aminopeptidase expression at 3 weeks. When AGP was considered the main effect, AGP supplementation (1) increased the V : C ratio in the ileum at 3 weeks of age; (2) increased sucrase mRNA expression in the duodenum at 3 weeks as well as the ileum at 6 weeks, and increased maltase expression in the ileum. The BS × AGP interaction was observed to affect average daily feed intake at 4 to 6 weeks, and duodenal sucrase and jejunal maltase expression at 3 weeks. Furthermore, dietary BS or AGP addition improved caecal microbial diversity at 3 weeks, and a BS × AGP interaction was observed (P < 0.05) for the Shannon and Simpson indexes. At the genus level, the relative abundance of Lactobacillus was found to be higher in the mixed group at 3 weeks and in the BS group at 6 weeks. Moreover, Anaerostipes, Dehalobacterium and Oscillospira were also found to be dominant genera in pullets with dietary BS addition. In conclusion, BS could improve intestinal morphology and change digestive enzyme relative expression and caecum microbiota, thereby increasing the efficiency of nutrient utilization. Our findings suggested that BS might have more beneficial effects than AGP in the study, which would provide theoretical evidence and new insight into BS application in layer pullets.
This paper provides an up-to-date review of the problems related to the generation, detection and mitigation of strong electromagnetic pulses created in the interaction of high-power, high-energy laser pulses with different types of solid targets. It includes new experimental data obtained independently at several international laboratories. The mechanisms of electromagnetic field generation are analyzed and considered as a function of the intensity and the spectral range of emissions they produce. The major emphasis is put on the GHz frequency domain, which is the most damaging for electronics and may have important applications. The physics of electromagnetic emissions in other spectral domains, in particular THz and MHz, is also discussed. The theoretical models and numerical simulations are compared with the results of experimental measurements, with special attention to the methodology of measurements and complementary diagnostics. Understanding the underlying physical processes is the basis for developing techniques to mitigate the electromagnetic threat and to harness electromagnetic emissions, which may have promising applications.
The Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80–300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new observational window in the southern hemisphere enabling many science areas. The driving science objectives of the original design were to observe 21 cm radiation from the Epoch of Reionisation (EoR), explore the radio time domain, perform Galactic and extragalactic surveys, and monitor solar, heliospheric, and ionospheric phenomena. All together
programs recorded 20 000 h producing 146 papers to date. In 2016, the telescope underwent a major upgrade resulting in alternating compact and extended configurations. Other upgrades, including digital back-ends and a rapid-response triggering system, have been developed since the original array was commissioned. In this paper, we review the major results from the prior operation of the MWA and then discuss the new science paths enabled by the improved capabilities. We group these science opportunities by the four original science themes but also include ideas for directions outside these categories.
We study the formation of fine radial jets during the impact of a compound drop on a smooth solid surface. The disperse-phase droplets are heavier than the outer continuous phase of the main drop and sink to the bottom of the drop before it is released from the nozzle. The droplets often arrange into a regular pattern around the axis of symmetry. This configuration produces narrow high-speed jets aligned with every internal droplet. These radial jets form during the early impulsive phase of the impact, by local focusing of the outer liquid, which is forced into the narrowing wedge under each internal droplet. The pressure-driven flow forces a thin sheet under and around each droplet, which levitates and separates from the solid surface. Subsequently, surface tension re-forms this horizontal sheet into a cylindrical jet, which is typically as narrow as
, while smaller droplets can produce even thinner jets. We systematically change the number of inner droplets and the properties of the main drop to identify the jetting threshold. The jet speed and thickness are minimally affected by the viscosity of the outer liquid, suggesting pure inertial focusing. The jets emerge at around eight times the drop impact velocity. Jetting stops when the density of the inner droplets approaches that of the continuous phase. The interior droplets are often greatly deformed and broken up into satellites by the outer viscous stretching, through capillary pinch-off or tip streaming.
There has been little reported on the transoral reconstructive options following salvage transoral robotic surgery. This paper describes the facial artery musculomucosal flap as a method to introduce vascularised tissue to a previously irradiated resection bed.
A facial artery musculomucosal flap was used to reconstruct the lateral pharyngeal wall in 13 patients undergoing salvage transoral robotic surgery for oropharyngeal squamous cell carcinoma. Outcomes recorded include flap and donor site complications, length of stay, and swallowing and speech outcomes.
There were no immediate or late flap complications, or cases of delayed wound healing in this series. There were two facial artery musculomucosal related complications requiring surgical management: one bleed from the facial artery musculomucosal donor site and one minor surgical revision. Healing of the flap onto the resection bed was successful in all cases.
The facial artery musculomucosal flap provides a suitable transoral local flap option for selected patients undergoing salvage transoral robotic surgery for oropharyngeal malignancies.
Space Infrared Telescope for Cosmology and Astrophysics (SPICA), the cryogenic infrared space telescope recently pre-selected for a ‘Phase A’ concept study as one of the three remaining candidates for European Space Agency (ESA's) fifth medium class (M5) mission, is foreseen to include a far-infrared polarimetric imager [SPICA-POL, now called B-fields with BOlometers and Polarizers (B-BOP)], which would offer a unique opportunity to resolve major issues in our understanding of the nearby, cold magnetised Universe. This paper presents an overview of the main science drivers for B-BOP, including high dynamic range polarimetric imaging of the cold interstellar medium (ISM) in both our Milky Way and nearby galaxies. Thanks to a cooled telescope, B-BOP will deliver wide-field 100–350
m images of linearly polarised dust emission in Stokes Q and U with a resolution, signal-to-noise ratio, and both intensity and spatial dynamic ranges comparable to those achieved by Herschel images of the cold ISM in total intensity (Stokes I). The B-BOP 200
m images will also have a factor
30 higher resolution than Planck polarisation data. This will make B-BOP a unique tool for characterising the statistical properties of the magnetised ISM and probing the role of magnetic fields in the formation and evolution of the interstellar web of dusty molecular filaments giving birth to most stars in our Galaxy. B-BOP will also be a powerful instrument for studying the magnetism of nearby galaxies and testing Galactic dynamo models, constraining the physics of dust grain alignment, informing the problem of the interaction of cosmic rays with molecular clouds, tracing magnetic fields in the inner layers of protoplanetary disks, and monitoring accretion bursts in embedded protostars.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
The search for life in the Universe is a fundamental problem of astrobiology and modern science. The current progress in the detection of terrestrial-type exoplanets has opened a new avenue in the characterization of exoplanetary atmospheres and in the search for biosignatures of life with the upcoming ground-based and space missions. To specify the conditions favourable for the origin, development and sustainment of life as we know it in other worlds, we need to understand the nature of global (astrospheric), and local (atmospheric and surface) environments of exoplanets in the habitable zones (HZs) around G-K-M dwarf stars including our young Sun. Global environment is formed by propagated disturbances from the planet-hosting stars in the form of stellar flares, coronal mass ejections, energetic particles and winds collectively known as astrospheric space weather. Its characterization will help in understanding how an exoplanetary ecosystem interacts with its host star, as well as in the specification of the physical, chemical and biochemical conditions that can create favourable and/or detrimental conditions for planetary climate and habitability along with evolution of planetary internal dynamics over geological timescales. A key linkage of (astro)physical, chemical and geological processes can only be understood in the framework of interdisciplinary studies with the incorporation of progress in heliophysics, astrophysics, planetary and Earth sciences. The assessment of the impacts of host stars on the climate and habitability of terrestrial (exo)planets will significantly expand the current definition of the HZ to the biogenic zone and provide new observational strategies for searching for signatures of life. The major goal of this paper is to describe and discuss the current status and recent progress in this interdisciplinary field in light of presentations and discussions during the NASA Nexus for Exoplanetary System Science funded workshop ‘Exoplanetary Space Weather, Climate and Habitability’ and to provide a new roadmap for the future development of the emerging field of exoplanetary science and astrobiology.