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In shape-from-focus (SFF) methods, a single focus measure is used to compute the focus volume. However, it seems that a single focus measure operator is not capable of computing accurate focus values for the images of diverse types of object shapes. Furthermore, most of the SFF methods try to improve the depth map without considering any additional structural or prior information. Consequently, the extracted shape of the object might lack important details. In this work, we address these problems and suggest a method in which depth hypotheses are combined for a more accurate 3D shape through 3D weighted least squares. First, depth hypotheses are obtained by applying a number of focus operators. Then, structural prior or guidance volume is extracted from the focus measure volumes. Finally, a 3D weighted least squares optimization technique is applied to the depth hypothesis volume, where weights are computed from the guidance volume. Thus, by inducing structural prior, an improved resultant depth map is obtained. The proposed method was tested using various image sequences of synthetic and microscopic real objects. Experimental results and comparative analysis demonstrated the effectiveness of the proposed method.
The objective of this study was to describe the epidemiology of COVID-19 in Nigeria with a view of generating evidence to enhance planning and response strategies. A national surveillance dataset between 27 February and 6 June 2020 was retrospectively analysed, with confirmatory testing for COVID-19 done by real-time polymerase chain reaction (RT-PCR). The primary outcomes were cumulative incidence (CI) and case fatality (CF). A total of 40 926 persons (67% of total 60 839) had complete records of RT-PCR test across 35 states and the Federal Capital Territory, 12 289 (30.0%) of whom were confirmed COVID-19 cases. Of those confirmed cases, 3467 (28.2%) had complete records of clinical outcome (alive or dead), 342 (9.9%) of which died. The overall CI and CF were 5.6 per 100 000 population and 2.8%, respectively. The highest proportion of COVID-19 cases and deaths were recorded in persons aged 31–40 years (25.5%) and 61–70 years (26.6%), respectively; and males accounted for a higher proportion of confirmed cases (65.8%) and deaths (79.0%). Sixty-six per cent of confirmed COVID-19 cases were asymptomatic at diagnosis. In conclusion, this paper has provided an insight into the early epidemiology of COVID-19 in Nigeria, which could be useful for contextualising public health planning.
Sigma-delta radio over fiber (ΣΔ-RoF) is an expedient technology for next-generation networks including 5G cloud/centralized radio access networks (C-RAN). In this article, we demonstrate a realistic experimental scenario for ΣΔ-RoF link targeting C-RAN fronthaul applications, by using baseband second-order 1-bit sigma-delta modulation (ΣΔ-M). The experimental set-up validates the LTE 20 MHz signals having modulation order of 256-quadrature amplitude modulation for a carrier frequency of 3 GHz, up to 10 km of standard single mode fiber. A detailed analysis of the ΣΔ-RoF system performance is reported by adjacent channel leakage ratio and error vector magnitude. Furthermore, an experimental study is evaluated where ΣΔ-RoF is compared with its counterparts. It is deduced that ΣΔ-RoF corroborates the present range of C-RAN fronthaul networks and can be a promising candidate for future mobile haul applications.
Grounding our research in social exchange theory and the conservation of resources perspective, we hypothesized a model that examines the effects of servant leadership (SL) on employees' workplace thriving via agentic work behaviors. To clarify the effects, employee core self-evaluations (CSEs) were investigated to determine boundary conditions on the relationship between SL and thriving. Data were collected at three points in time from 260 professionals across diverse functional backgrounds and industries. The analysis results confirmed an indirect effect from SL to workplace thriving via agentic work behaviors. Importantly, the moderation results demonstrated that the relationship between SL and workplace thriving is stronger when individuals have high CSEs. Implications for theory and practice are discussed.
This paper presents a two-elements based, dual polarized, single layer, patch antenna array with improved isolation between transmit (Tx) and receive (Rx) ports for 2.4 GHz in-band full duplex (IBFD) or simultaneous transmit and receive wireless applications. The differential feeding deployed at the Rx port effectively suppresses the coupling which is termed as self-interference from the Tx port to achieve high Tx–Rx interport isolation. A simple 3 dB/180° ring hybrid coupler with nice amplitude and phase balance characteristics has been used for differential Rx operation. The mathematical description for a differential feeding based self-interference cancellation mechanism is also presented for the proposed dual polarized IBFD antenna array. The measurement results for the implemented prototype of the antenna array demonstrate very nice levels of Tx–Rx interport isolation. The implemented single layer, compact antenna array presents 10 dB return-loss bandwidth of more than 50 MHz for both Tx and Rx ports. The prototype achieves >80 dB peak interport isolation and 75 dB (65 dB) isolation in 20 MHz (50 MHz) bandwidth.
Improving the production traits and resistance against mastitis in dairy cattle is a challenge for animal scientists across the globe. The present study was designed to investigate the genetic effects of single nucleotide polymorphisms (SNPs) in Janus kinase 2 (JAK2) and diacylglycerol acyltransferase (DGAT1) genes with production and mastitis-related traits. Four SNPs in JAK2 and one in DGAT1 were analyzed through Chinese Cow's SNPs Chip-I (CCSC-I) and genotyped in a population of 312 Chinese Holsteins. Our findings demonstrated that milk fat percentage, somatic cell count (SCC), somatic cell score (SCS), serum cytokines interleukin 6 (IL-6) and interferon gamma (IFN-γ) showed significant associations (P < 0.05) with at least one or more identified SNPs. Consequently, the analysis based on haplotypes amongst the SNPs in JAK2 revealed noteworthy (P < 0.05) association with SCC and IL-6. Collectively, our results verified the pleiotropic ability of detected SNPs in bovine JAK2 and DGAT1 for milk fat percentage as well as mastitis-related traits. The significant SNPs in both the genes could serve as powerful genetic markers to minimize mastitis risk. In addition, besides SCC and SCS, the IFN-γ and IL-6 could also be used as indicators of improved genetic resistance against mastitis.
Maize (Zea mays L.) grain yield is severely constrained by drought and this study was conducted to assess gains in grain yield and other traits of released maize cultivars. Twenty-three maize cultivars plus a check were evaluated under drought and well-watered conditions at Zaria and Kadawa during 2015/2016 and 2016/2017 dry seasons. The 24 cultivars were evaluated using 6 x 4 lattice design with three replications. Genotypes differed significantly for all measured traits except anthesis-silking interval (ASI), husk cover, and number of ears per plant under drought, and ASI, husk cover, and ear aspect under well-watered conditions. Under drought, grain yield ranged from 2251 kg ha−1 for SAMMAZ 31 to 4938 kg ha−1 for SAMMAZ 19, with a genetic gain of 1.93% yr−1. Under well-watered conditions, grain yield varied from 3082 kg ha−1 for SAMMAZ 37 to 5689 kg ha−1 for SAMMAZ 51, with the same genetic gain found under drought conditions. Grain yield reduction as a result of drought was 28.4% and performance under drought predicted performance under well-watered conditions better than vice versa with regression coefficient value of 0.8. Grain yield had significant correlations with all measured traits under both water conditions, except for husk cover, plant and ear heights under drought. Our data revealed that substantial genetic gains have been made in breeding for high grain yield cultivars under drought and well-watered conditions over a period of 16 years in Nigeria.
Unlike in most other regions, Karakoram glaciers are either stable or advancing, a phenomenon known as the Karakoram anomaly. Despite studies of glacier surges and the derivation of surface velocity maps, the spatiotemporal variability of glacier dynamics still remains poorly understood, particularly in the Eastern Karakoram Range. We use Advanced Land Observing Satellite/the Phased Array type L-band Synthetic Aperture Radar (ALOS/PALSAR)-1/2 data from 2007 to 2011 and 2014 to 2015 to examine detailed surface velocity patterns of the Siachen, Baltoro, Kundos, Singkhu and Gasherbrum Glaciers. The first three glaciers show considerable velocity variability (20–350 m a−1), with clear seasonal patterns. Although all glaciers, except for Baltoro, flow slowest in 2015, the velocity structures are individual and vary in space and time. In Gasherbrum Glacier, peak surge-phase velocities are seasonally modulated, with maxima in summers 2006 and 2007, suggesting surface melt plays an important role in maintaining the active phase. Given the relatively close proximity of these glaciers, we assume that surface melt timing and rates are comparable. We therefore argue that the observed spatiotemporal and interannual velocity patterns are determined by local and internal mechanisms, including englacial and subglacial hydrology, thermal processes and tributary configuration of each individual glacier.
This study explores the relationships of negative affectivity with two frequently studied outcome variables job performance and turnover intentions. Conventional wisdom holds that negative affectivity has a harmful impact on both job performance and intentions to leave; however, we propose a more nuanced perspective using empirical and theoretical arguments (e.g., self-regulation theory) to highlight the functional effects of negative affectivity. To test our hypotheses, we collected self-reported and supervisor-reported data from seven organizations in Pakistan. The findings based on data collected from 280 employees show that while negative affectivity is detrimental for job performance, this effect is mitigated as negative affectivity increases. It further shows that the linear negative main effect of negative affectivity on job performance is more pronounced when employees experience less time-related work stress. Finally, the curvilinear relationship between negative affectivity and turnover intentions is moderated by time-related work stress. The relationship has a U shape at high levels of time-related work stress, whereas at low levels it has an inverted U shape. A discussion of the limitations, future research, and implications for theory building and practice conclude the article.
A ternary Nickel foam (NF)–graphene/MnO2/polyaniline (PANI) nanocomposite has been synthesized using green chemistry approach (in situ polymerization). All reactants were dispersed homogeneously in precursor solution in the form of ions and molecules. PANI and MnO2 molecules on the NF–graphene contact each other and are arranged alternately in the composite. Alternative arrangement of PANI and MnO2 nanoparticles separates them and prevents the aggregation of PANI and MnO2 to decrease the particle size of the composite on the surface of NF–graphene. The intermolecule contact improves the conductivity of the composite. The composite showed excellent specific capacitance of 1081 F/g at a scan rate of 1 mV/s and specific capacitance of 815 F/g at a current density of 3 A/g, having excellent cycling stability. Current study provides an alternative pathway to improve the rate capability and cycling stability of nanostructured electrodes, by offering a great promise for their applications in supercapacitors.
Drawing upon the Conservation of Resources Theory, we investigated the hitherto unexplored role of ‘social resources’ (i.e., trust in supervisor and social interaction) in mediating the relationship between ‘self-regulation of emotions’ (i.e., a personal resource) and work engagement. The data were collected from 296 IT professionals at four well-established IT firms in Ukraine. As we hypothesized, self-regulation of emotions positively affected work engagement, yet this effect partially disappeared when controlling for the role of social resources. Together, these findings illustrate the dynamic role of an individual's personal and social resources in fostering work engagement.
We determined cytokines (e.g. interleukin-8, 10, 12 and TNF-α) expression by peripheral blood mononuclear cells (PBMCs) and in rectal mucosa in diarrhoea-predominant irritable bowel syndrome (D-IBS) with Blastocystis spp. Eighty patients with D-IBS and Blastocystis spp. infection were classified as ‘cases’ and 80 with D-IBS without Blastocystis spp. infection were classified as ‘control’. Cases were subdivided into D-IBS and Blastocystis sp. defined type 1 (subtype-specific primer SB83) and type 3 (SB227). Stool microscopy and culture were performed. Rectal biopsies were obtained for histology and cytokines by real-time PCR for mRNA expression of cytokines. PBMCs IL-8 was similar in different groups but in type 1, IL-8mRNA was increased compared with type 3 (P = 0·001) and control (P = 0·001). In type 1, IL-10 by PBMCs had a low mean value (14·5±1·6) compared with (16·7±1·5) type 3 and (16±2·3) in controls (P<0·001 and P<0·001, respectively). In Blastocystis sp. type 1, low IL-10 was associated with lymphocyte and plasma cell infiltration (P = 0·015 and P = 0·002, respectively). In Blastocystis sp. type 1 and type 3, IL-12 was associated with goblet cell depletion 23 (85%) (P<0·001) and 8 (29%) (P = 0·037), respectively. In Blastocystis sp. type 1, low IL-10 was associated with a proinflammatory response characterized by IL-8.
In the South-East Asian subcontinent, flatbreads contribute the main portion of carbohydrate to a meal. There are no specific data on the effect of different flatbreads on satiety and recurrent hunger, as indicated by the duration of ghrelin suppression after a meal. The present study was designed to examine the glycaemic, insulin and ghrelin responses to traditional subcontinental breads in type 2 diabetic subjects and healthy volunteers. For this purpose, twelve normoglycaemic healthy volunteers and ten type 2 diabetic patients, in the fasting state, consumed one of five common flatbreads on consecutive days. Capillary blood glucose was examined in the fasting state and serially for 5 h after a meal. Serum insulin and ghrelin levels were determined at hourly intervals for 5 h after the consumption of bran and plain chapatti flatbreads. The incremental area under the curve (iAUC) was calculated for glycaemic and insulin responses, while the net AUC was used to assess the ghrelin response. The results showed that glycaemic and insulin iAUC were lowest for bran chapatti, and highest for plain chapatti. Furthermore, bran chapatti showed maximum ghrelin suppression in both normal and diabetic groups. In conclusion, the low-glycaemic index bran chapatti flatbread had a lower postprandial glycaemic excursion and insulin response, and a more prolonged suppression of ghrelin levels, compared with the plain chapatti flatbread, and in each case, the difference was greater for the diabetic subjects than for the normal subjects. The inclusion of these flatbreads in the diabetic/weight-reducing diet may help weight loss by promoting satiety and reducing hyperinsulinaemia.
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