bluuebunny/crossref_metadata_2025 huggingface dataset:
Roles of OmpA in Type III Secretion System-Mediated Virulence of Enterohemorrhagic Escherichia coli
Authors: Hirakawa Hidetada , Suzue Kazutomo , Takita Ayako , Tomita Haruyoshi
Published: November 2021

Outer membrane proteins are commonly produced by gram-negative bacteria, and they have diverse functions. A subgroup of proteins, which includes OmpA, OmpW and OmpX, is often involved in bacterial pathogenesis. Here we show that OmpA, rather than OmpW or OmpX, contributes to the virulence of enterohemorrhagic Escherichia coli (EHEC) through its type III secretion system (T3SS). Deletion of ompA decreased secretion of the T3SS proteins EspA and EspB; however, the expression level of the LEE genes that encode a set of T3SS proteins did not decrease. The ompA mutant had less abilities to form A/E lesions in host epithelial cells and lyse human red blood cells than the parent strain. Moreover, the virulence of an ompA mutant of Citrobacter rodentium (traditionally used to estimate T3SS-associated virulence in mice) was attenuated. Mice infected with the ompA mutant survived longer than those infected with the parent strain. Furthermore, mice infected with ompA developed symptoms of diarrhea more slowly than mice infected with the parent strain. Altogether, these results suggest that OmpA sustains the activity of the T3SS and is required for optimal virulence in EHEC. This work expands the roles of outer membrane proteins in bacterial pathogenesis.
Ceragenin-Coated Non-Spherical Gold Nanoparticles as Novel Candidacidal Agents
Authors: Skłodowski Karol , Chmielewska Sylwia Joanna , Depciuch Joanna , Deptuła Piotr , Piktel Ewelina , Daniluk Tamara , Zakrzewska Magdalena , Czarnowski Michał , Cieśluk Mateusz , Durnaś Bonita , Parlińska-Wojtan Magdalena , Savage Paul B. , Bucki Robert
Published: November 2021

Background: Infections caused by Candida spp. have become one of the major causes of morbidity and mortality in immunocompromised patients. Therefore, new effective fungicides are urgently needed, especially due to an escalating resistance crisis. Methods: A set of nanosystems with rod- (AuR), peanut- (AuP), and star-shaped (AuS) metal cores were synthesized. These gold nanoparticles were conjugated with ceragenins CSA-13, CSA-44, and CSA-131, and their activity was evaluated against Candida strains (n = 21) through the assessment of MICs (minimum inhibitory concentrations)/MFCs (minimum fungicidal concentrations). Moreover, in order to determine the potential for resistance development, serial passages of Candida cells with tested nanosystems were performed. The principal mechanism of action of Au NPs was evaluated via ROS (reactive oxygen species) generation assessment, plasma membrane permeabilization, and release of the protein content. Finally, to evaluate the potential toxicity of Au NPs, the measurement of hemoglobin release from red blood cells (RBCs) was carried out. Results: All of the tested nanosystems exerted a potent candidacidal activity, regardless of the species or susceptibility to other antifungal agents. Significantly, no resistance development after 25 passages of Candida cells with AuR@CSA-13, AuR@CSA-44, and AuR@CSA-131 nanosystems was observed. Moreover, the fungicidal mechanism of action of the investigated nanosystems involved the generation of ROS, damage of the fungal cell membrane, and leakage of intracellular contents. Notably, no significant RBCs hemolysis at candidacidal doses of tested nanosystems was detected. Conclusions: The results provide rationale for the development of gold nanoparticles of rod-, peanut-, and star-shaped conjugated with CSA-13, CSA-44, and CSA-131 as effective candidacidal agents.
Novel N7-Arylmethyl Substituted Dinucleotide mRNA 5′ cap Analogs: Synthesis and Evaluation as Modulators of Translation
Authors: Wojcik Radoslaw , Baranowski Marek R. , Markiewicz Lukasz , Kubacka Dorota , Bednarczyk Marcelina , Baran Natalia , Wojtczak Anna , Sikorski Pawel J. , Zuberek Joanna , Kowalska Joanna , Jemielity Jacek
Published: November 2021

Dinucleotide analogs of the messenger RNA cap (m7GpppN) are useful research tools and have potential applications as translational inhibitors or reagents for modification of in vitro transcribed mRNAs. It has been previously reported that replacing the methyl group at the N7-position with benzyl (Bn) produces a dinucleotide cap with superior properties. Here, we followed up on this finding by synthesizing 17 novel Bn7GpppG analogs and determining their structure–activity relationship regarding translation and translational inhibition. The compounds were prepared in two steps, including selective N7-alkylation of guanosine 5′-monophosphate by arylmethyl bromide followed by coupling with imidazole-activated GDP, with total yields varying from 22% to 62%. The compounds were then evaluated by determining their affinity for eukaryotic translation initiation factor 4E (eIF4E), testing their susceptibility to decapping pyrophosphatase, DcpS—which is most likely the major cellular enzyme targeting this type of compound—and determining their translation inhibitory properties in vitro. We also synthesized mRNAs capped with the evaluated compounds and tested their translational properties in A549 cells. Our studies identified N7-(4-halogenbenzyl) substituents as promising modifications in the contexts of either mRNA translation or translational inhibition. Finally, to gain more insight into the consequences at the molecular level of N7-benzylation of the mRNA cap, we determined the crystal structures of three compounds with eIF4E.
Improvement of Growth, Yield, Seed Production and Phytochemical Properties of Satureja khuzistanica Jamzad by Foliar Application of Boron and Zinc
Authors: Mumivand Hasan , Khanizadeh Parisa , Morshedloo Mohammad Reza , Sierka Edyta , Żuk-Gołaszewska Krystyna , Horaczek Tomasz , Kalaji Hazem M.
Published: November 2021

Satureja khuzistanica Jamzad is a valuable and endemic medicinal plant. Boron and zinc are essential elements for the vegetative and reproductive growth of plants and have significant effects on yield, essential oil composition and the seed production of plants. To investigate the effects of the foliar application of zinc and boron on the growth, yield, seed production and phytochemical properties of S. khuzistanica, a study was conducted in a factorial experiment with three replicates in two consecutive years based on a randomized complete block design. The foliar application of boron (B) at three concentrations (control or distilled water, 0.4% and 0.8% as H3BO3) and zinc (Zn) at three concentrations (control or distilled water, 0.3% and 0.6% as ZnSO4) was carried out. Our results showed that the foliar application of B resulted in a significant increase in the fresh and dry weights of plants, the dry weight of stems, drug yield, seed yield, seed germination and 1000-seed weight. At the same time, the application of B resulted in a significant decrease in seed emptiness. The fresh and dry weights of plants, drug yield, seed yield, 1000-seed weight and seed germination were also significantly improved by Zn foliar spraying compared to the control. Application of 0.8% B resulted in a significant decrease in seed emptiness by 14.16% and 22.37%, as compared to the control. The foliar spraying of B and Zn improved the total phenolic content, the essential oil content and the yield and antioxidant activity of S. khuzistanica. Moreover, B application generally concentrated more carvacrol in the essential oil (in the first experimental year). In contrast, no significant differences were observed between Zn treatments in carvacrol content and total flavonoids. The use of several microelements, such as B and Zn, could improve both the quantity and quality of S. khuzistanica. Additionally, improvement of seed set and seed quality by the foliar spraying of Zn and B may be useful for growing plants in arid and semi-arid areas.
LED Illumination for High-Quality High-Yield Crop Growth in Protected Cropping Environments
Authors: Rahman Md Momtazur , Field David Luke , Ahmed Soyed Mohiuddin , Hasan Md Tanvir , Basher Mohammad Khairul , Alameh Kamal
Published: November 2021

Vegetables and herbs play a central role in the human diet due to their low fat and calory content and essential antioxidant, phytochemicals, and fiber. It is well known that the manipulation of light wavelengths illuminating the crops can enhance their growth rate and nutrient contents. To date, it has not been easy to generalize the effects of LED illumination because of the differences in the plant species investigated, the measured traits, the way wavelengths have been manipulated, and the plants’ growing environments. In order to address this gap, we undertook a quantitative review of LED manipulation in relation to plant traits, focusing on vegetables and herbs. Here, we use standardized measurements of biomass, antioxidant, and other quantitative characteristics together with the whole range of the photosynthetic photon flux density (PPFD). Overall, our review revealed support for the claims that the red and blue LED illumination is more reliable and efficient than full spectrum illumination and increases the plant’s biomass and nutritional value by enhancing the photosynthetic activity, antioxidant properties, phenolic, and flavonoids contents. Although LED illumination provides an efficient way to improve yield and modify plant properties, this study also highlights the broad range of responses among species, varieties traits, and the age of plant material.
Physico-Chemical, Nutritional, and Sensory Evaluation of Two New Commercial Tomato Hybrids and Their Parental Lines
Authors: Felföldi Zoltán , Ranga Floricuta , Socaci Sonia Ancuta , Farcas Anca , Plazas Mariola , Sestras Adriana F. , Vodnar Dan Cristian , Prohens Jaime , Sestras Radu E.
Published: November 2021

Tomato (Solanum lycopersicum) is the globally most consumed vegetable. The objective of this research was to analyze physico-chemical, nutritional and sensorial components (taste and flavor) in two new commercial hybrids (AS 300 F1 and AS 400 F1) and their four F7 parental lines. Two widely grown F1 hybrids (Precos F1 and Addalyn F1) were used as controls. The results obtained for carbohydrates (HPLC-RID) indicated that the highest values (27.82 mg/g) were recorded in the paternal line AS 10 of the new hybrid AS 400 F1. The highest values of total organic acids (HPLC-VWD) were recorded in Addalyn F1 (5.06 m/g), while the highest value of phenolic compounds (HPLC-DAD-ESI⁺) were identified in the maternal line AS 09 of the hybrid AS 400 F1 (96.3 µg/g). Intrinsic sensory values were analyzed by male and female tasters of different ages using a hedonic scale. The tasters’ perception revealed obvious taste differences between tomato genotypes. The study allowed determining genetic parameters of interest (heterosis and heterobeltosis) for the new hybrids, as well as a detailed characterization of the chemical composition and organoleptic quality of the parental breeding lines and their hybrids, which is useful in tomato breeding.
LightCue: An Innovative Far-Red Light Emitter for Locally Modifying the Spectral Cue in Outdoor Conditions with Global Consequences on Plant Architecture
Authors: Fortineau Alain , Combes Didier , Richard-Molard Céline , Frak Ela , Jullien Alexandra
Published: November 2021

Plasticity of plant architecture is a promising lever to increase crop resilience to biotic and abiotic damage. Among the main drivers of its regulation are the spectral signals which occur via photomorphogenesis processes. In particular, branching, one of the yield components, is responsive to photosynthetic photon flux density (PPFD) and to red to far-red ratio (R:FR), both signals whose effects are tricky to decorrelate in the field. Here, we developed a device consisting of far-red light emitting diode (LED) rings. It can reduce the R:FR ratio to 0.14 in the vicinity of an organ without changing the PPFD in outdoor high irradiance fluctuating conditions, which is a breakthrough as LEDs have been mostly used in non-fluctuant controlled conditions at low irradiance over short periods of time. Applied at the base of rapeseed stems during the whole bolting-reproductive phase, LightCue induced an expected significant inhibitory effect on two basal targeted axillary buds and a strong unexpected stimulatory effect on the overall plant aerial architecture. It increased shoot/root ratio while not modifying the carbon balance. LightCue therefore represents a promising device for progress in the understanding of light signal regulation in the field.
Fabrication of Highly Microporous Structure Activated Carbon via Surface Modification with Sodium Hydroxide
Authors: Hafizuddin Mohd Sahfani , Lee Chuan Li , Chin Kit Ling , H’ng Paik San , Khoo Pui San , Rashid Umer
Published: November 2021

The aim of this study was to select the optimal conditions for the carbonization process followed by surface modification treatment with sodium hydroxide (NaOH) to obtain a highly microporous activated carbon structure derived from palm kernel shells (PKS) and coconut shells (CS). The effects of the carbonization temperature and NaOH concentration on the physiochemical properties, adsorption capability, specific surface area, surface morphology, and surface chemistry of PKS and CS were evaluated in this study. The results show that surface-modified activated carbons presented higher surface area values (CS: 356.87 m2 g−1, PKS: 427.64 m2 g−1), smaller pore size (CS: 2.24 nm, PKS: 1.99 nm), and larger pore volume (CS: 0.34 cm3 g−1, PKS: 0.30 cm3 g−1) than the untreated activated carbon, demonstrating that the NaOH surface modification was efficient enough to improve the surface characteristics of the activated carbon. Moreover, surface modification via 25% NaOH greatly increases the active functional group of activated carbon, thereby directly increasing the adsorption capability of activated carbon (CS: 527.44 mg g−1, PKS: 627.03 mg g−1). By applying the NaOH post-treatment as the ultimate surface modification technique to the activated carbon derived from PKS and CS, a highly microporous structure was produced.
Geometrical Scaling Effects in the Mechanical Properties of 3D-Printed Body-Centered Cubic (BCC) Lattice Structures
Authors: Aziz Alia Ruzanna , Zhou Jin , Thorne David , Cantwell Wesley James
Published: November 2021

This paper investigates size effects on the mechanical response of additively manufactured lattice structures based on a commercially available polylactic acid (PLA) polymer. Initial attention is focused on investigating geometrical effects in the mechanical properties of simple beams and cubes. Following this, a number of geometrically scaled lattice structures based on the body-centered cubic design were manufactured and tested in order to highlight size effects in their compression properties and failure modes. A finite element analysis was also conducted in order to compare the predicted modes of failure with those observed experimentally. Scaling effects were observed in the compression response of the PLA cubes, with the compression strength increasing by approximately 19% over the range of scale sizes investigated. Similar size-related effects were observed in the flexural samples, where a brittle mode of failure was observed at all scale sizes. Here, the flexural strength increased by approximately 18% when passing from the quarter size sample to its full-scale counterpart. Significant size effects were observed following the compression tests on the scaled lattice structures. Here, the compression strength increased by approximately 60% over the four sample sizes, in spite of the fact that similar failure modes were observed in all samples. Finally, reasonably good agreement was observed between the predicted failure modes and those observed experimentally. However, the FE models tended to over-estimate the mechanical properties of the lattice structures, probably as a result of the fact that the models were assumed to be defect free.
Microfibrillated Cellulose Grafted with Metacrylic Acid as a Modifier in Poly(3-hydroxybutyrate)
Authors: Popa Marius Stelian , Frone Adriana Nicoleta , Radu Ionut Cristian , Stanescu Paul Octavian , Truşcă Roxana , Rădiţoiu Valentin , Nicolae Cristian Andi , Gabor Augusta Raluca , Panaitescu Denis Mihaela
Published: November 2021

This work proposes a new method for obtaining poly(3-hydroxybutyrate) (PHB)/microfibrillated cellulose (MC) composites with more balanced properties intended for the substitution of petroleum-based polymers in packaging and engineering applications. To achieve this, the MC surface was adjusted by a new chemical route to enhance its compatibility with the PHB matrix: (i) creating active sites on the surface of MC with γ-methacryloxypropyltrimethoxysilane (SIMA) or vinyltriethoxysilane (SIV), followed by (ii) the graft polymerization of methacrylic acid (MA). The high efficiency of the SIMA-MA treatment and the lower efficiency in the case of SIV-MA were proven by the changes observed in the Fourier transform infrared FTIR spectra of celluloses. All modified celluloses and the PHB composites containing them showed good thermal stability close to the processing temperature of PHB. SIMA-modified celluloses acted as nucleating agents in PHB, increasing its crystallinity and favoring the formation of smaller spherulites. A uniform dispersion of SIMA-modified celluloses in PHB as a result of the good compatibility between the two phases was observed by scanning electron microscopy and many agglomerations of fibers in the composite with unmodified MC. The dual role of SIMA-MA treatment, as both compatibilizer and plasticizer, was pointed out by mechanical and rheological measurements. This new method to modify MC and obtain PHB/MC composites with more balanced stiffness–toughness properties could be a solution to the high brittleness and poor processability of PHB-based materials.
On the Applicability of Electrophoresis for Protein Quantification
Authors: Dome Karina , Akimenko Zoya , Bychkov Aleksey , Kalambet Yuri , Lomovsky Oleg
Published: November 2021

Polyacrylamide gel electrophoresis is widely used for studying proteins and protein-containing objects. However, it is employed most frequently as a qualitative method rather than a quantitative one. This paper shows the feasibility of routine digital image acquisition and mathematical processing of electropherograms for protein quantification when using vertical gel electrophoresis and Chrom & Spec software. Both the well-studied model protein molecules (bovine serum albumin) and more complex real-world protein-based products (casein-containing isolate for sports nutrition), which were subjected to mechanical activation in a planetary ball mill to obtain samples characterized by different protein denaturation degrees, were used as study objects. Protein quantification in the mechanically activated samples was carried out. The degree of destruction of individual protein was shown to be higher compared to that of the protein-containing mixture after mechanical treatment for an identical amount of time. The methodological approach used in this study can serve as guidance for other researchers who would like to use electrophoresis for protein quantification both in individual form and in protein mixtures. The findings prove that photographic imaging of gels followed by mathematical data processing can be applied for analyzing the electrophoretic data as an affordable, convenient and quick tool.
Theoretical Investigation of the Influence of Wavelength on the Bandwidth in Multimode W-Type Plastic Optical Fibers with Graded-Index Core Distribution
Authors: Simović Ana , Savović Svetislav , Drljača Branko , Djordjevich Alexandar , Min Rui
Published: November 2021

The bandwidth of multimode W-type plastic optical fibers (POFs) with graded-index (GI) core distribution is investigated by solving the time-dependent power flow equation. The multimode W-type GI POF is designed from a multimode single-clad (SC) GI POF fiber upon modification of the cladding layer of the latter. Results show how the bandwidth in W-type GI POFs can be enhanced by increasing the wavelength for different widths of the intermediate layer and refractive indices of the outer cladding. These fibers are characterized according to their apparent efficiency to reduce modal dispersion and increase bandwidth.
Preparation and Characterization of Calcium Cross-Linked Starch Monolithic Cryogels and Their Application as Cost-Effective Green Filters
Authors: Boonkanon Chanita , Phatthanawiwat Kharittha , Chuenchom Laemthong , Lamthornkit Nareumon , Taweekarn Tarawee , Wongniramaikul Worawit , Choodum Aree
Published: November 2021

Monolithic cryogels from starch were successfully synthesized and applied as alternative biodegradable filters for the first time. Rice flour was cross-linked with Ca2+ from limewater during gelatinization before being frozen and then thawed for three cycles. The resultant material was then soaked in ethanol for 3 h before incubation at 80 °C for 1 h, yielding monolithic material with interconnected pores in sizes of 51 ± 18 to 52 ± 15 µm without any need of freeze-drying. The cryogels possessed macroporous structure with specific surface areas from 1.1 to 4.3 m2g−1, they could adsorb water from 599 ± 27 to 635 ± 59% of their dry weight with low swelling ratios of 6.0 ± 0.3 to 6.4 ± 0.6 gwater/gcryogel, and could be applied as biofilters to remove suspended particles and reduce the light absorption of water sample from 25 ± 3 to 96 ± 5%. The prepared biofilters can be re-used up to three times, although they cost only USD 0.0004/piece. Complete weight loss resulted from burial in soil for 30 days, indicating environmentally friendly biodegradation and potential for environmental applications.
Whiteness in Christianity and Decoloniality of the African Experience: Developing a Political Theology for ‘Shalom’ in Kenya
Authors: Munyao Martin , Tanui Philemon Kipruto
Published: November 2021

The decolonial discourse around Christianity must not avoid dealing with Whiteness if there is going to be any fruitful decolonization. Colonialism and the Western missionary enterprise were not necessarily two distinct and unrelated entries to precolonial Kenya. How then did Christianity, for decades, live side by side with colonialism? In this article, we contend that Colonialism in Kenya could not have been possible without the missionary enterprise activity. The impact of that unholy relationship is felt and sustained in contemporary forms of violence. Unfortunately, critics of such a discourse dismiss the decolonial efforts in African Christianity citing intellectual activism. Such voices of dissent may not be far from the truth as Jesus’ ministry involved elements of activism. Whenever he confronted oppressive institutional structures, he used activism tempered with a degree of pacifism. Looking at the history of historical injustices in Kenya, we see instances whereby missionary Christianity conveniently abetted injustices for colonial structures to sustain the oppression of the indigenous Africans. Such injustices have been unresolved to date because the oppressive structures are still in place in the shape of neocolonialism. Land, for example, is a present source of conflict in Kenya. In the precolonial African ontology, the land was in harmony with the people. For land to be taken away from its owners, a separation of the people from the land had to happen. This was facilitated by a Christian theology that created existential dualism, violently separating the African bodies from their souls and the person from the community. Hence, Christian doctrine that emphasized ‘saving souls’ and ‘personal salvation’ was entrenched. This separation and fragmentation are fundamental to Whiteness. Whiteness universalizes truth, even theology; it puts a face of neutrality that obscures specificity. Such has made the church uncritical of oppressive and unjust political structures. Whiteness realizes that it is hard to enter into something that is in harmony. Therefore, separation needs to happen for Whiteness to succeed. Unfortunately, much of our theological understanding today is tempered with a neocolonial mindset that separates the soul from the body for Christian triumphalism. It anesthetizes the pain of oppression with the eschatological promise of future deliverance. This paper will analyze the impact of Whiteness in Kenya during and after colonialism to demonstrate how the British explorer–settler–missionary alliance ‘oiled’ the religious and economic disenfranchising of African people. Secondly, it proposes a political theology that will restore ‘Shalom’ in a socially, economically, and spiritually broken country. It is such a theology undertaken in Africa that will confront oppressive structures and identify with the marginalized communities in Kenya.
Theorizing the (Un)Sounded in Sikhī: Anhad, Sabad, and Kīrtan
Authors: Kaur Inderjit N.
Published: November 2021

Listening to sabad kīrtan (sung scriptural verse) is a core, everyday, widespread, and loved worship practice of Sikhs around the globe. Thus, it would be fair to state that sounding is central to Sikh worship. Indeed, the Sikh scripture considers kīrtan to be an eminent mode of devotion. Yet, the ultimate aim of this sonic practice is to sense the “unsounded” vibration—anhad—and thereby the divine and divine ethical virtues. Based on a close reading of Sikh sacred texts and ethnographic research, and drawing on the analytic of transduction, the paper explicates the embodied vibratory dimensions of the (unsounded) anhad and (sounded) sabad kīrtan. It argues that the central purpose of the Sikh (un)sounding perceptual practice is embodied ethical attunement for an unmediated experience of the divine and divine ethical virtues, and thereby the development of an ethical life. At the intersection of music, sound, religious, and philosophical studies, the analysis reveals the centrality of the body in worship and ethical development, and contributes to interdisciplinary conversations on sensory epistemologies in faith traditions.
The Transit of Mary Magdalene’s Soul in Catalan Artistic Production in the 15th Century
Authors: Monzón Pertejo Elena
Published: November 2021

There are a great many studies on the figure of Mary Magdalene in different areas of knowledge. Nevertheless, there is a gap as regards the image of this character in Catalonia, and specifically regarding the visual representation of her soul at the moment when she died. This text aims to analyze this matter based on two Catalan altarpieces: the Altarpiece of Saint Mary Magdalene from Perella (Bernat Martorell, 1437–1453) and The Death of Mary Magdalene (Jaume Huguet, 1465–1480). The analysis has been carried out based on the postulates from the tradition of studies on iconography and iconology: the relationships between image and text, the history of the iconographic types and the magnetic power of images. The basic hypothesis is that the representation of Mary Magdalene’s soul in the 15th Century in Catalonia is visually borrowed from the iconographic type of the Dormition of the Mother of God. To test this, comparative analyses have been made of the visual representation of the two women and also of the textual sources, such as the canonical and extracanonical gospels, a variety of medieval legends and different hagiographies or vitas and sermons from the period.
Crop Rotation Modeling for Deep Learning-Based Parcel Classification from Satellite Time Series
Authors: Quinton Félix , Landrieu Loic
Published: November 2021

While annual crop rotations play a crucial role for agricultural optimization, they have been largely ignored for automated crop type mapping. In this paper, we take advantage of the increasing quantity of annotated satellite data to propose to model simultaneously the inter- and intra-annual agricultural dynamics of yearly parcel classification with a deep learning approach. Along with simple training adjustments, our model provides an improvement of over 6.3% mIoU over the current state-of-the-art of crop classification, and a reduction of over 21% of the error rate. Furthermore, we release the first large-scale multi-year agricultural dataset with over 300,000 annotated parcels.
Monitoring and Analyzing Yield Gap in Africa through Soil Attribute Best Management Using Remote Sensing Approaches: A Review
Authors: Khechba Keltoum , Laamrani Ahmed , Dhiba Driss , Misbah Khalil , Chehbouni Abdelghani
Published: November 2021

Africa has the largest population growth rate in the world and an agricultural system characterized by the predominance of smallholder farmers. Improving food security in Africa will require a good understanding of farming systems yields as well as reducing yield gaps (i.e., the difference between potential yield and actual farmer yield). To this end, crop yield gap practices in African countries need to be understood to fill this gap while decreasing the environmental impacts of agricultural systems. For instance, the variability of yields has been demonstrated to be strongly controlled by soil fertilizer use, irrigation management, soil attribute, and the climate. Consequently, the quantitative assessment and mapping information of soil attributes such as nitrogen (N), phosphorus (P), potassium (K), soil organic carbon (SOC), moisture content (MC), and soil texture (i.e., clay, sand and silt contents) on the ground are essential to potentially reducing the yield gap. However, to assess, measure, and monitor these soil yield-related parameters in the field, there is a need for rapid, accurate, and inexpensive methods. Recent advances in remote sensing technologies and high computational performances offer a unique opportunity to implement cost-effective spatiotemporal methods for estimating crop yield with important levels of scalability. However, researchers and scientists in Africa are not taking advantage of the opportunity of increasingly available geospatial remote sensing technologies and data for yield studies. The objectives of this report are to (i) conduct a review of scientific literature on the current status of African yield gap analysis research and their variation in regard to soil properties management by using remote sensing techniques; (ii) review and describe optimal yield practices in Africa; and (iii) identify gaps and limitations to higher yields in African smallholder farms and propose possible improvements. Our literature reviewed 80 publications and covered a period of 22 years (1998-2020) over many selected African countries with a potential yield improvement. Our results found that (i) the number of agriculture yield-focused remote sensing studies has gradually increased, with the largest proportion of studies published during the last 15 years; (ii) most studies were conducted exclusively using multispectral Landsat and Sentinel sensors; and (iii) over the past decade, hyperspectral imagery has contributed to a better understanding of yield gap analysis compared to multispectral imagery; (iv) soil nutrients (i.e., NPK) are not the main factor influencing the studied crop productivity in Africa, whereas clay, SOC, and soil pH were the most examined soil properties in prior papers.
Optimization of Landsat Chl-a Retrieval Algorithms in Freshwater Lakes through Classification of Optical Water Types
Authors: Dallosch Michael A. , Creed Irena F.
Published: November 2021

The application of remote sensing data to empirical models of inland surface water chlorophyll-a concentrations (chl-a) has been in development since the launch of the Landsat 4 satellite series in 1982. However, establishing an empirical model using a chl-a retrieval algorithm is difficult due to the spatial heterogeneity of inland lake water properties. Classification of optical water types (OWTs; i.e., differentially observed water spectra due to differences in water properties) has grown in favour in recent years over traditional non-turbid vs. turbid classifications. This study examined whether top-of-atmosphere reflectance observations in visible to near-infrared bands from Landsat 4, 5, 7, and 8 sensors can be used to identify unique OWTs using a guided unsupervised classification approach in which OWTs are defined through both remotely sensed reflectance and surface water chemistry data taken from samples in North American and Swedish lakes. Linear regressions of algorithms (Landsat reflectance bands, band ratios, products, or combinations) to lake surface water chl-a were built for each OWT. The performances of chl-a retrieval algorithms within each OWT were compared to those of global chl-a algorithms to test the effectiveness of OWT classification. Seven unique OWTs were identified and then fit into four categories with varying degrees of brightness as follows: turbid lakes with a low chl-a:turbidity ratio; turbid lakes with a mixture of high chl-a and turbidity measurements; oligotrophic or mesotrophic lakes with a mixture of low chl-a and turbidity measurements; and eutrophic lakes with a high chl-a:turbidity ratio. With one exception (r2 = 0.26, p = 0.08), the best performing algorithm in each OWT showed improvement (r2 = 0.69–0.91, p < 0.05), compared with the best performing algorithm for all lakes combined (r2 = 0.52, p < 0.05). Landsat reflectance can be used to extract OWTs in inland lakes to provide improved prediction of chl-a over large extents and long time series, giving researchers an opportunity to study the trophic states of unmonitored lakes.
In Situ Determination of Dry and Wet Snow Permittivity: Improving Equations for Low Frequency Radar Applications
Authors: Webb Ryan W. , Marziliano Adrian , McGrath Daniel , Bonnell Randall , Meehan Tate G. , Vuyovich Carrie , Marshall Hans-Peter
Published: November 2021

Extensive efforts have been made to observe the accumulation and melting of seasonal snow. However, making accurate observations of snow water equivalent (SWE) at global scales is challenging. Active radar systems show promise, provided the dielectric properties of the snowpack are accurately constrained. The dielectric constant (k) determines the velocity of a radar wave through snow, which is a critical component of time-of-flight radar techniques such as ground penetrating radar and interferometric synthetic aperture radar (InSAR). However, equations used to estimate k have been validated only for specific conditions with limited in situ validation for seasonal snow applications. The goal of this work was to further understand the dielectric permittivity of seasonal snow under both dry and wet conditions. We utilized extensive direct field observations of k, along with corresponding snow density and liquid water content (LWC) measurements. Data were collected in the Jemez Mountains, NM; Sandia Mountains, NM; Grand Mesa, CO; and Cameron Pass, CO from February 2020 to May 2021. We present empirical relationships based on 146 snow pits for dry snow conditions and 92 independent LWC observations in naturally melting snowpacks. Regression results had r2 values of 0.57 and 0.37 for dry and wet snow conditions, respectively. Our results in dry snow showed large differences between our in situ observations and commonly applied equations. We attribute these differences to assumptions in the shape of the snow grains that may not hold true for seasonal snow applications. Different assumptions, and thus different equations, may be necessary for varying snowpack conditions in different climates, suggesting that further testing is necessary. When considering wet snow, large differences were found between commonly applied equations and our in situ measurements. Many previous equations assume a background (dry snow) k that we found to be inaccurate, as previously stated, and is the primary driver of resulting uncertainty. Our results suggest large errors in SWE (10–15%) or LWC (0.05–0.07 volumetric LWC) estimates based on current equations. The work presented here could prove useful for making accurate observations of changes in SWE using future InSAR opportunities such as NISAR and ROSE-L.
Remote Sensing of Aerosols at Night with the CoSQM Sky Brightness Data
Authors: Marseille Charles , Aubé Martin , Barreto Africa , Simoneau Alexandre
Published: November 2021

Aerosol optical depth is an important indicator of aerosol particle properties and their associated radiative impacts. AOD determination is very important to achieve relevant climate modelling. Most remote sensing techniques to retrieve aerosol optical depth are applicable to daytime given the high level of light available. The night represents half of the time but in such conditions only a few remote sensing methods are available. Among these approaches, the most reliable are moon photometers and star photometers. In this paper, we attempt to fill gaps in the aerosol detection performed with the aforementioned techniques using night sky brightness measurements during moonless nights with the novel CoSQM, a portable, low-cost and open-source multispectral photometer. In this paper, we present an innovative method for estimating the aerosol optical depth using an empirical relationship between the zenith night sky brightness measured at night with the CoSQM and the aerosol optical depth retrieved during daytime from the AErosol Robotic NETwork. Although the proposed method does not measure the AOD directly, an empirical relationship with the CE318-T is shown to give good results at the location of Santa Cruz de Tenerife. Such a method is especially suited to light-polluted regions with light pollution sources located within a few kilometres of the observation site. A coherent day-to-night aerosol optical depth and Ångström Exponent evolution in a set of 354 days and nights from August 2019 to February 2021 was verified at the location of Santa Cruz de Tenerife on the island of Tenerife, Spain. The preliminary uncertainty of this technique was evaluated using the variance under stable day-to-night conditions, set at 0.02 for aerosol optical depth and 0.75 for the Ångström Exponent. These results indicate the set of CoSQM and the proposed methodology appear to be a promising tool, adding new information on the optical properties of aerosols at night, which could be of key importance in improving climate predictions.
COVID-19 Mortality in Patients with a Ward-Based Ceiling of Care
Authors: Ingram Matthew , Tullo Ellen , Mackay Laura , Aujayeb Avinash ,   Northumbria COVID-19 Audit Collaborative
Published: November 2021

Objectives: COVID-19 patients thought unlikely to benefit from organ support, thereby having a ward-based ceiling of care (WBCoC), represent a distinct subgroup. There are no associated studies in mortality. We sought to identify clinical risk factors for inpatient COVID-19 mortality. Design and setting: this was a retrospective observational study of patients admitted to Northumbria Healthcare NHS Foundation Trust. Clinical variables were associated with inpatient mortality via logistic regression. Participants: all patients admitted with COVID-19 infection and who had a WBCoC at point of admission were included (n = 114). Main outcome measures: the outcome measure was inpatient death.
Assessment of the Impact of Road Transport Change on the Security of the Urban Social Environment
Authors: Vitkūnas Rolandas , Činčikaitė Renata , Meidute-Kavaliauskiene Ieva
Published: November 2021

In the context of accelerating urbanisation, cities must ensure a viable economy, social well-being, and a healthy environment. Transport is one of the key conditions for economic development and meeting the needs of countries, regions, and cities. However, transport must meet not only the physiological but also the social needs of society, one of which is environmental security. Urban transport accounts for around 40% of CO2 emissions and 70% of other pollutants from road transport. Thus, one of the most difficult issues for any city to address when building bypasses is the growing number of cars in the city, traffic congestion, and the reduction of all greenhouse gas emissions. The documents adopted in July 2020 aim to revitalise the EU’s economy by moving towards a green economy and sustainability. In addition to the systematic and comparative analysis of concepts published in the scientific literature, the article also presents an analysis of the concepts of the sustainable city and sustainable transport, as well as a study of the social impact of bypasses and the assessment of the security of the social environment in the Baltic capitals. The aim of the article is to assess the impact of the growing number of vehicles on the security of the city’s social environment. Research results show that the number of pollutants and a direct dependence between the number of pollutants and the driving speed were established. Therefore, it needs to make investments in the transport sector: improving roads, the construction of bypasses, and the technical parameters of purchased cars.
The Influence of Environment Factors on Chronic Non-Communicable Diseases in a Heavy Industry City—A Case of Xigu District of Lanzhou City
Authors: Zhao Haili , Du Yuhan , Li Jialiang , Wu Minghui , Zhang Fang
Published: November 2021

Taking Xigu District of Lanzhou City as an example, this paper systematically analyzes the spatio-temporal distribution characteristics of patients with chronic non-communicable diseases (NCD) and compares the differences between heating period and non-heating period. Furthermore, the impact paths of natural environmental factors and built-up environmental factors on NCD are probed with the help of the geographic detector. The results are as follows: In time, the incidence of NCD in Xigu district fluctuated from 2012 to 2019. In space, there was an overall declining trend in high incidence rate from the central area to the surrounding areas, among which Xigucheng street was the high-risk area. The incidence of NCD in heating period was higher than that of in non-heating period, and the number of H-H cluster areas was witnessed an obviously increasing growth in Sijiqing Street. There are significant differences in the explanatory power of different factors (if any) for NCD. The explanatory power of each index in Xigu District is as follows: Facility > SO2 > NO2 > PM2.5 > food > Beverage Service > Green Facilities > Traffic Regulations > medical facilities. The interaction between plant facilities and SO2 has the strongest effect on NCD. Except for the negative correlation between greening and medical facilities and the incidence of NCD, all the influencing factors were positively correlated with NCD.
The Measurement and Temporal and Spatial Evolution of Tourism Poverty Alleviation Efficiency in the Liupan Mountain Area of Gansu Province, China
Authors: Wang Yaobin , Song Ying , Chen Guangfeng , Huang Shihua , Wang Meizhen , Pan Yinggang
Published: November 2021

Poverty is a chronic problem all over the world. Since the 18th National Congress of the Communist Party of China was held in 2012, the Chinese government has continuously increased its poverty alleviation efforts. In addition, absolute poverty in China was eliminated by the end of 2020. Tourism has played an important role in poverty alleviation. To explore the role of the tourism industry in reducing poverty, this paper takes the Liupan Mountain area of Gansu Province in western China, as a case site. An input–output evaluation index system was constructed, and a Super-SBM model was used to evaluate the tourism poverty alleviation efficiency in 40 districts and counties in the Liupan Mountain area from 2009 to 2018. The results show that the overall starting point of tourism poverty alleviation efficiency in the study area was high, which needed to be further optimized. The difference in tourism poverty alleviation efficiency among districts and counties tended to decrease in the time series. The restrictive factors were the lack of technological progress and lack of innovation. The spatial distribution of tourism poverty alleviation efficiency in the study area presented a pattern of high in the east and low in the west, high in the north and low in the south. In the future, the tourism poverty alleviation efficiency in the concentrated and contiguous destitute areas of the Liupan Mountain area in Gansu Province could be improved by cultivating the tourism industry, strengthening technological innovation, cultivating core growth poles, and exerting radiation effects.
Sustainability Psychology of Disruption: Attitude towards Water Purification Technology Can Be Predicted by Cultural Value Orientation and Personality Traits
Authors: Abraham Juneman , Salsabilla Indhira , Warnars Harco Leslie Hendric Spits , Manurung Rudi Hartono , Ruman Yustinus Suhardi
Published: November 2021

The clean water crisis, particularly drinking water, is an issue that is strongly tied to water sustainability. The availability of disruptive technology that is cheaper and easy to use, such as a water purifier, is one answer to the ongoing crisis. Unfortunately, a disparity exists in the attitudes of Indonesia’s society toward this technology. Five cultural orientations are set as predictors, each hypothesized as able to predict such attitudes as mediated by relevant personality traits. This study applied a correlational-predictive design toward 244 individuals (112 males and 132 females, Mage = 23.766 years old, SDage = 6.196 years) residing in Jakarta, Indonesia’s capital city. The main results were: (1) uncertainty avoidance can predict attitudes toward water purification technology through the conscientiousness trait; (2) power distance is unable to predict attitudes through neuroticism; (3) collectivism can predict attitudes through agreeableness; (4) masculinity is unable to predict attitudes through extraversion; and (5) long-term orientation can predict attitudes toward water purification technology through the openness trait. Prior studies have generally employed culture and personality as two separate predictors, yet this study might be the first in setting culture and personality as socio-psychological processes that shape a person’s attitude toward water purification technology in a single theoretical model.
Earth Observations and Statistics: Unlocking Sociodemographic Knowledge through the Power of Satellite Images
Authors: Merodio Gómez Paloma , Juarez Carrillo Olivia Jimena , Kuffer Monika , Thomson Dana R. , Olarte Quiroz Jose Luis , Villaseñor García Elio , Vanhuysse Sabine , Abascal Ángela , Oluoch Isaac , Nagenborg Michael , Persello Claudio , Brito Patricia Lustosa
Published: November 2021

The continuous urbanisation in most Low-to-Middle-Income-Country (LMIC) cities is accompanied by rapid socio-economic changes in urban and peri-urban areas. Urban transformation processes, such as gentrification as well as the increase in poor urban neighbourhoods (e.g., slums) produce new urban patterns. The intersection of very rapid socio-economic and demographic dynamics are often insufficiently understood, and relevant data for understanding them are commonly unavailable, dated, or too coarse (resolution). Traditional survey-based methods (e.g., census) are carried out at low temporal granularity and do not allow for frequent updates of large urban areas. Researchers and policymakers typically work with very dated data, which do not reflect on-the-ground realities and data aggregation hide socio-economic disparities. Therefore, the potential of Earth Observations (EO) needs to be unlocked. EO data have the ability to provide information at detailed spatial and temporal scales so as to support monitoring transformations. In this paper, we showcase how recent innovations in EO and Artificial Intelligence (AI) can provide relevant, rapid information about socio-economic conditions, and in particular on poor urban neighbourhoods, when large scale and/or multi-temporal data are required, e.g., to support Sustainable Development Goals (SDG) monitoring. We provide solutions to key challenges, including the provision of multi-scale data, the reduction in data costs, and the mapping of socio-economic conditions. These innovations fill data gaps for the production of statistical information, addressing the problems of access to field-based data under COVID-19.