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Background Pakistan introduced Ten-valent pneumococcal-conjugate-vaccine PCV10 in 2012 as a 3 + 0 schedule without catch-up. Methods Children

The potential of microalgae as an alternative energy source has been adequately studied. However, exclusive use of microalgae as an energy feedstocks cannot warrant their scalability and economical sustainability due to the high cost involved in their biomass processing. The co-processing of microalgae biomass with other related bio-refinery applications can offset their cost and improve their sustainability. Thus, it triggers up the need of exploring the potential of microalgae biomass beyond their typical use. Microalgae offer interesting features to qualify them as alternative feedstocks for various bio-refinery applications. Microalgae have unique abilities to utilize them for industrial and environmental applications. Thus, this review discusses to expand the scope of integrating microalgae with other biotechnological applications to enhance their sustainability. The use of microalgae as a feed for animal and aquaculture, fertilizers, medicine, cosmetic, environmental and other biotechnological applications is thoroughly reviewed. It also highlights the barriers, opportunities, developments, and prospects of extending the scope of microalgae. This study concludes that sustained research funding, and a shift of microalgae focus from biofuels production to bio-refinery co-products can qualify them as promising feedstocks. Moreover, technology integration is inevitable to off-set the cost of microalgae biomass processing. It is expected that this study would be helpful to determine the future role of microalgae in bio-refinery applications.

For signature verification systems, micro deformations can be defined as the small differences in the same strokes of signatures or special writing habits of different signers. These micro deformations can reveal the core distinction between the genuine signatures and skilled forgeries. In this paper, we prove that Convolutional Neural Networks (CNNs) have the potential to extract those micro deformations by max-pooling. More specifically, the micro deformations can be determined by watching the location coordinates of the maximum values in pooling windows of max-pooling. Extensive analysis and experiments demonstrate that it is possible to achieve state-of-the-art performance by using this location information as a new feature for capturing micro deformations, along with convolutional features. The proposed method outperforms the state-of-the-art systems on four publicly available datasets of different languages, i.e., English (GPDSsynthetic, CEDAR), Persian (UTSig), and Hindi (BHSig260).

This paper has a threefold contribution. First, it presents a novel online handwriting database captured using a digital/sensor pen (Apple pencil) and digital/sensor screen (iPad). The captured data are continuous streams of multi-dimensional points, analyzed and processed to classify handwritten sequences into plain text, mathematical expressions, and plots/graphs. Second, a new feature set for online handwritten sequence classification is proposed. The said feature set is used to establish a benchmark for the proposed dataset using various machine-learning classifiers. Third, an ablation study is performed to look into the performance of the proposed feature set compared to the existing feature sets. Here, the proposed feature set has outperformed all the existing feature sets in various evaluation metrics. Furthermore, the proposed dataset and the feature set have been made publicly available along with the benchmark evaluation to enable further research in the field.

The studies of core–shell nanoparticles have gained significant interests due to the high stability and probable template to form a core–shell complex by coating on them with organic or inorganic substances. The silica nanoparticle covered with cobalt is especially important because it has a chemically stable core. Co3O4-NF was synthesized by the calcination of Co(OH)2@SiO2 under atmospheric air for oxygen reduction and evolution reactions. After calcination, Ag deposition was performed to produce Ag@Co3O4-NF and their surface area reduces from 125.68 to 108.12 m2/g. The crystallanity and morphological features were observed by the X-ray diffraction (XRD) and scanning electron microscopy (SEM). Furthermore, Ag@Co3O4-NF catalysts exhibited superior electrochemical performance as a cathode material for Zinc-air batteries. The cyclic test for charging and discharging was performed for 500 h revealing Ag@Co3O4-NF a potential catalyst, having splendid stability for the OER and ORR.

Background & Aims Environmental enteric dysfunction (EED) limits the Sustainable Development Goals of improved childhood growth and survival. We applied mucosal genomics to advance our understanding of EED. Methods The Study of Environmental Enteropathy and Malnutrition (SEEM) followed 416 children from birth to 24 months in a rural district in Pakistan. Biomarkers were measured at 9 months and tested for association with growth at 24 months. The duodenal methylome and transcriptome were determined in 52 undernourished SEEM participants and 42 North American controls and patients with celiac disease. Results After accounting for growth at study entry, circulating insulin-like growth factor-1 (IGF-1) and ferritin predicted linear growth, whereas leptin correlated with future weight gain. The EED transcriptome exhibited suppression of antioxidant, detoxification, and lipid metabolism genes, and induction of anti-microbial response, interferon, and lymphocyte activation genes. Relative to celiac disease, suppression of antioxidant and detoxification genes and induction of antimicrobial response genes were EED-specific. At the epigenetic level, EED showed hyper-methylation of epithelial metabolism and barrier function genes, and hypo-methylation of immune response and cell proliferation genes. Duodenal coexpression modules showed association between lymphocyte proliferation and epithelial metabolic genes and histologic severity, fecal energy loss, and wasting (weight-for-length/height Z < -2.0). Leptin was associated with expression of epithelial carbohydrate metabolism and stem cell renewal genes. Immune response genes were attenuated by giardia colonization. Conclusions Children with reduced circulating IGF-1 are more likely to experience stunting. Leptin and a gene signature for lymphocyte activation and dysregulated lipid metabolism are implicated in wasting, suggesting new approaches for EED refractory to nutritional intervention. ClinicalTrials.gov, Number: NCT03588013. (https://clinicaltrials.gov/ct2/show/NCT03588013), Graphical abstract

The dataset described in this paper was collected for a time-series cross-sectional study exploring the impact of 10-valent Pneumococcal Conjugate Vaccine (PCV10) on nasopharyngeal (NP) carriage in children under 2 years of age from a rural population in Sindh, Pakistan. The study was carried out in two union councils of Matiari - Khyber and Shah Alam Shah Jee Wasi (Latitude 25.680298 / Longitude 68.502711). Data was collected on socio-demographics, clinical characteristics and vaccination status using android phone-based application. NP samples were collected using standard World Health Organisation (WHO) techniques, culture and serotyping was done using sequential Multiplex PCR described by Centre for Disease Control, USA. We looked at the carriage rate of vaccine type (VT) and non-vaccine type (NVT) serotypes over time in vaccinated and unvaccinated children. We additionally looked at the predictors for pneumococcal carriage. The uploaded dataset, available on Mendeley data repository (Nisar, Muhammad Imran (2021), "Impact of PCV10 on nasopharyngeal carriage in children in Pakistan", Mendeley Data, V1, doi:10.17632/t79h6g97gr.1), has 3140 observations in CSV format. Additional files uploaded include a data dictionary and the set of questionnaires. The dataset and accompanying files can be used by other interested researchers to replicate our analysis, carry similar analysis under varying set of assumptions or perform additional exploratory or metanalysis.

The wide structural versatility of the Metal-Organic Framework (MOF) is considered to be potential catalysts. In this work, [Mn (BDC). nDMF]n was synthesized by the reaction of 1,4-benzene dicarboxylic acid (1,4-BDC) with Manganese (II) nitrate using a solvothermal method. The [Mn (BDC). nDMF]n crystals were calcined for 2 h to produce Mn-MOF derived catalysts (C@MnO catalysts). The formation of MnO crystals was investigated by the X-ray diffraction (XRD) and the Raman Spectroscopy analyzed the graphitization. The resulting catalysts, C@MnO are highly porous with a high specific surface area of 291.62 m2/g at 700 °C. After calcination, Ni deposition was performed, to produce Ni@C@MnO on which Ni-atoms are deposited on the surface of MnO. The surface area reduces to 214.09 m2/g at 700 °C and the structure is distorted due to deposition. Numerous characterization techniques, including XRD, SEM, EDS, TGA, and Raman, strongly support the effective incorporation of Mn and Ni into the material frameworks. When applied as a cathode for Zinc-air battery, the Ni@C@MnO electrode delivered a high current density of 0.206 Acm−2 for the OER. The cyclic test for charging-discharging was performed for 152 cycles revealing a potential catalyst, having splendid stability for the OER and ORR.

The fabrication of efficient catalysts for the oxygen evolution reactions (OER) that are required to accelerate the sluggish kinetics of metal-air batteries has attracted significant attention for application in energy conversion devices. Metal-organic frameworks (MOFs) have been recognized as potential candidates for the formation of promising catalysts. In this study, we report the formation of Ni/CNT/CoNi using bimetallic-ZIF (CoNi-ZIF) as a precursor. Bimetallic CoNi encapsulated in carbon nanotubes (CNTs) was obtained by calcinating CoNi-ZIF-67 to yield CNT/CoNi. The resulting CNT/CoNi was highly porous with a significant specific surface area of 242 m2/g. After calcination, Ni deposition on the CNT was performed and the surface area was reduced to 168.7 m2/g. Ni/CNT/CoNi was applied as a cathode material in zinc-air batteries, exhibiting excellent electrochemical performance and cycling stability.

In this study, we examine the average and extreme dependence between Exchange Traded Funds ETFs (both energy & commodity) and WTI crude oil prices by using EGARCH-copula models. We use both static (Normal, Student-t, Gumbel and Clayton) and time-varying (Normal and SJC) copulas to explore both average and extreme dependence. Based on the Akaike information criterion (AIC), our results show that time-varying copulas outperform the static copulas. Further, we have found strong enough positive correlations of energy and commodity ETFs with oil prices to suggest that they could be used as a tool for managing oil price risk. Also, contrasting results of time-varying copulas with each other provide useful information regarding the hedge or safe-haven properties of energy and commodity ETFs.

Zeolitic imidazolate framework containing cobalt and nickel (Co- and Ni-ZIF-67) were used as a precursor to perform Ni deposition, in order to obtain enhanced catalytic activity and nanocatalysts. Co or Ni embedded in the carbon nanotubes (CNTs) were obtained by the heat treatment of Co- or Ni-ZIF-67. On Co or Ni embedded CNTs, Ni-deposition was performed to obtain the Ni-deposited catalysts, Ni-CNT-(Co or Ni), which have a higher surface area of 136.7 and 259 m2/g, respectively. These catalysts exhibit superior performance, low overpotential, and high stability for both oxygen reduction and evolution reactions. The superior performance is attributed to metal deposition, which creates highly active catalytic sites and has potential application as a catalyst for the rechargeable zinc-air battery.

Co3O4 nanoflowers (NFs) were obtained from cobalt hydroxide coated on silica, Co(OH)2@SiO2, prepared from a homogenous mixture of urea and cobalt nitrate in an aqueous solution. The Co3O4@SiO2 was obtained by calcining Co(OH)2@SiO2 under atmospheric air for 3 h and then immersing in sodium hydroxide to yield Co3O4-NFs. The Ni-deposited Co3O4 NFs (Ni@Co3O4-NFs) were synthesized by chemical deposition of nickel nanoparticles onto Co3O4-NF by a reducing agent, NaBH4. The physical characterization of Co3O4-NFs and Ni@Co3O4-NFs was performed by Brunauer-Emmett-Teller analysis, scanning electron microscopy and X-ray diffraction. The electrochemical properties of Co3O4-NFs and Ni@Co3O4-NFs for the oxygen reduction and evolution reaction were determined in an 8 M KOH solution. Ni@Co3O4-NF showed a better cell performance than that of Co3O4-NF. Moreover, Ni@Co3O4-NF exhibited a higher stability and longer life cycles at 20 mA cm−2 at a 2 h charging and discharging rate as compared to Co3O4-NF. Therefore, Co3O4-NF and Ni@Co3O4-NF could be used as a cathode material for Zn-air rechargeable batteries.

Trifluoroethanol (TFE) mimics the membrane environments as it simulates the hydrophobic environment and better stabilizes the secondary structures in peptides owing to its hydrophobicity and hydrogen bond-forming properties. Its dielectric constant approximates that of the interior of proteins and is one-third of that of water. Human serum albumin (HSA) is a biological transporter. The effect of TFE on HSA gives the clue about the conformational changes taking place in HSA on transport of ligands across the biological membranes. At 25% (v/v) and 60% (v/v) TFE, HSA exhibits non-native β-sheet, altered tryptophan fluorescence, exposed hydrophobic clusters, increased thioflavin T fluorescence and prominent red shifted Congo red absorbance, and large hydrodynamic radii suggesting the aggregate formation. Isothermal titration calorimetric results indicate weak binding of TFE and HSA. This suggests that solvent-mediated effects dominate the interaction of TFE and HSA. TEM confirmed prefibrillar at 25% (v/v) and fibrillar aggregates at 60% (v/v) TFE. Comet assay of prefibrillar aggregates showed DNA damage causing cell necrosis hence confirming cytotoxic nature. On increasing concentration of TFE to 80% (v/v), HSA showed retention of native-like secondary structure, increased Trp and ANS fluorescence, a transition from β-sheet to α-helix. Thus, TFE at high concentration possess anti- aggregating potency.

The contribution of this article is twofold. First, we propose a sketch-based system, namely the a.SCatch system, for querying a floor plan repository. Second, for generating such a repository, a novel complete system for floor plan analysis is presented. The latter system extracts the semantics from existing floor plans. We introduce novel preprocessing methods, e.g., the differentiation between thick, medium, and thin lines and the removal of components outside the convex hull of the outer walls. Especially, the use of the convex hull increases the performance of the final system. The a.SCatch system enables the user to easily access knowledge from past projects. The user searches for semantically similar floor plans just by drawing parts of the new plan. An algorithm extracts the semantic structure sketched by the architect on DFKI's Touch &Write table. Finally, the extracted structures are compared using the graph matching, and the most similar one is retrieved. In our experiments for floor plan analysis on a reference data set we compare our approach to other approaches available in the literature. We show that our floor plan analysis system outperforms previous systems. Also the performance of the sketch recognition system is quite high. Overall, the performance of the floor plan analysis, as well as of the retrieval, is already good for the use in practice.

This paper aims to study the extent of overinvestment, underinvestment problem and measure its impact on corporate performance. Our sample consists of 7 years data (2005 to 2011) of 360 non-financial companies listed in the Singapore Stock Market. After panel data models appropriation tests (LM test, Hausman test, No Fixed effect test) we employed fixed effect regression methodology in our analysis. Our results show that 52% firms in our sample are engaged in proper investment projects, 29% firms are overinvesting, while 19% firms are underinvesting. Maximum overinvestment is taking place in Basic Material sector while maximum underinvestment happening in Healthcare sector. Further tests show that both overinvestment and underinvestment shows severe negative impact on firm performance. However, proper investment has positive impact on firm performance in Singapore Stock Market. The results highlight the extent of agency problem in Singapore Stock Market. Moreover, it depicts the importance of investment activities of Singaporean companies for the international investors and portfolio managers.

Did the terrorist attacks of September 11, 2001 change the volatility dynamics of stock markets? Using daily returns data from Pakistan, a front line state in the war against terror, we investigate whether important time series characteristics, for example first-order time dependence in the mean and conditional variance, the conditional variance risk premium, and the asymmetric response of the conditional variance to innovations, have changed during the post-9/11 period in comparison to these characteristics during the pre-9/11 period. Our results show that the volatility behavior changed significantly after the terrorist attacks of 9/11. We show that this sudden shift in the volatility behavior cannot be explained by the implementation of regulatory reforms. We divide pre-9/11 period into the pre- and the post-reform periods and show that the volatility behavior during both of these periods was qualitatively the same.

What happens to analysts' performance when market intermediaries are not governed properly? Using analysts' recommendation data from Pakistan, we find that analysts' performance deteriorate significantly as the unscrupulous behavior of market intermediaries increase. Deterioration in analysts' performance is more evident after the introduction of corporate governance code. We argue that this sharp decline in analysts' performance is at least partly due to the accumulation of market power by these intermediaries. We propose that improvement in firm-level governance mechanisms alone is not sufficient to develop capital markets in the newly emerging economies. The market intermediaries should also be subject to proper governance mechanisms.

This paper investigates the earnings management response to Russian Corporate Governance reforms during the year 2002 when corporate governance codes were introduced. We study the effect of these codes on the earnings management practices of Russian companies. The event-study analysis is carried on employing cross-sectional Jones (1991) Model to detect the earnings management in both periods. Our null hypothesis of 'No Earnings Management in event-period' is rejected; however, the analyses highlight a decline in the use of absolute discretionary accruals during the reform period. We also found that companies' compliance with IAS/USGAAP is significantly affecting the discretionary powers of the managers of these companies. International accounting standards and USGAAP provide clear indication of no earnings management in the subsequent firm-year. Both cross-sectional and panel data models show positive (inflating) abnormal accruals in Ferrous Metal industry and negative (deflating) abnormal accruals in Telecom industry. Whereas, Oil & Gas and power industries are more transparent in disclosing earnings in terms of managerial discretionary powers of using firm's earnings. We found significantly lower absolute earnings management in these industries that represents better shareholders' rights. The results are robust in favour of obvious earnings management practices in Russia during 1998 to 2003. However, we do not neglect the positive impacts of reforms that have urged the management to use more transparent methods to disclose actual performance but full impact is yet to happen when high concentrated ownership and insider trading exists. More targeted and refined codes are needed to overcome the excessive discretionary power problem in Russia.

This study demonstrates how hedging methodologies can be evaluated in a modern risk management context and provides a hedging effectiveness of dynamic hedge ratios. The results provide an indication of the superior performance of the time varying hedge ratio as compared with traditional constant ratio. Time varying hedge ratio estimated by CCC-GARCH model shows a clear advantage over linear regression based constant hedge ratio in minimizing the variance (risk) of portfolio returns over the whole 10 years of analysis. The time-varying hedge ratio estimated in our study provides an efficient measure for bond investors to maximize the value of their investments by changing positions in both spot and future markets of U.S. Treasuries with the change in actual yields of cash market. The results are robust in the sense that constant conditional correlation model does take account of the conditional heteroskedasticity present in the data in case of spot market.