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In this paper we investigate a class of integrals that were encountered in the course of a work on statistical plasma physics, in the so-called Sommerfeld temperature-expansion of the electronic entropy. We show that such integrals, involving some parameters, can be fully described in closed form represented by special functions. [ABSTRACT FROM AUTHOR]

In this paper, we investigate one in the family of four parametric linear Euler sums as given by Alzer and Choi and later extended by Sofo and Choi. We give explicit expressions for a variety of special cases involving a free parameter. Our analysis incorporates the properties of the polylogarithm function, commonly referred to as the Fermi–Dirac integral. A reciprocity property is utilized to highlight an explicit representation of a particular skew harmonic linear Euler sum. A number of examples are also given which highlight the theorems. This work generalizes some results in the published literature. [ABSTRACT FROM AUTHOR]

We investigate the linear arrangement of Euler harmonic sums that may be expressed in closed form in terms of special functions such as the classical Riemann zeta function and the Dirichlet eta function. Particular emphasis is given to Euler harmonic sums with even weight. New examples highlighting the theorems will be presented. [ABSTRACT FROM AUTHOR]

Carrion decomposition has a significant impact on soil chemical profiles. However, soil nutrient research associated with animal carcasses in Antarctica has been relatively scarce, and the effect of penguin carrion decomposition on soil chemical composition is largely unknown. We aimed to determine Antarctica's soil chemistry profiles associated with penguin carrion. Soil samples were collected from a penguin rookery near King Sejong Station, Barton Peninsula, King George Island, Antarctica. Dry combustion methods were used to identify soil nitrogen and sulfur, while ammonia, nitrate, and phosphate were determined colorimetrically using a spectrophotometer. In addition, total carbon, pH, electrical conductivity, soil moisture, and soil porosity were also determined. Overall, soil chemical properties were not significantly different between the stages of decomposition and the sampling locations. These findings suggest that nutrients from penguin carrion disperse and leach in limited quantities into the soil, probably due to the active scavenging activities by vertebrate scavengers and the slower decomposition rate resulting from cold temperatures in the Antarctic region. [ABSTRACT FROM AUTHOR]

In this paper we investigate the representation of integrals involving the product of the Legendre Chi function, polylogarithm function and log function. We will show that in many cases these integrals take an explicit form involving the Riemann zeta function, the Dirichlet Eta function, Dirichlet lambda function and many other special functions. Some examples illustrating the theorems will be detailed. [ABSTRACT FROM AUTHOR]

Climate change negatively affects crop productivity, threatening the survival of entire populations from many vulnerable hotspot regions of the world with the risk of exacerbating hunger, malnutrition and international inequality. Selecting plant species manifesting abiotic stress-tolerant adaptive traits represents a challenge towards ensuring that crops are more resistant and resilient to environmental perturbations. The rhizosheath, defined as the complex of root hair, exudates and soil that strongly adheres to plant roots, is a promising root adaptive trait in facing conditions of water and nutrient deficits, as well as acidic soil. Several beneficial ecological functions are attributed to the rhizosheath, such as enhancing water and nutrient uptake; protecting from dehydration, heat and acid stresses; and stimulating microbial activities. It has been described in several Angiosperm species, including crops grown in severe habitats. The aim of this review was to collect the relevant literature produced to date regarding rhizosheaths, focusing on (i) the various processes involved in its formation, including both physicochemical and biological ones; (ii) the evolutionary and ecological role of rhizosheaths; and (iii) the most frequently used methodologies for its investigation and characterization. The present work provides a comprehensive overview of this revolutionary root's great agronomic importance in order to address future research aiming to fill the existing knowledge gaps and define a common and shared methodology. [ABSTRACT FROM AUTHOR]

The article focuses on the evolution of contemporary painting in Ghana since its independence in 1957, employing the concept of "morphing" to describe the gradual transformation of artistic styles and identities. It identifies three generations of Ghanaian artists, delving into their unique approaches and thematic shifts. It specifically examines the contributions of artists Rikki Wemega-Kwawu and Brother Owusu-Ankomah from Sekondi-Takoradi, challenging the historical oversight of this urban center in Ghanaian art history.

A very recent article delved into and expanded the four parametric linear Euler sums, revealing that two well-established subjects—Euler sums and series involving the zeta functions—display particular correlations. In this study, we present several closed forms of series involving zeta functions by using formulas for series associated with the zeta functions detailed in the aforementioned paper. Another closed form of series involving Riemann zeta functions is provided by utilizing a known identity for a series of rational functions in the series index, expressed in terms of Gamma functions. Furthermore, we demonstrate a myriad of applications and relationships of series involving the zeta functions and the extended parametric linear Euler sums. These include connections with Wallis's infinite product formula for π , Mathieu series, Mellin transforms, determinants of Laplacians, certain integrals expressed in terms of Euler sums, representations and evaluations of some integrals, and certain parametric Euler sum identities. The use of Mathematica for various approximation values and certain integral formulas is elaborated upon. Symmetry naturally occurs in Euler sums. [ABSTRACT FROM AUTHOR]

People are facing uncertain and difficult times in the face of the Covid-19 pandemic. The benefits of plants (psychological, health, economic, productive) in this period of forced isolation can be of key importance. If many of us have to self-isolate in urban or suburban environments, we need something to do to keep our bodies and minds active and fed. In such a challenging scenario, a vegetable garden in home spaces can bring recreational, health, economic and environmental benefits. Regardless of the Covid-19 pandemic, there is untapped potential for this kind of garden to impact environmental outcomes, public awareness, and market trends. Home vegetable gardens could provide a small-scale approach to the sustainable use of natural resources, leading towards self-sufficiency, self-regulation, sustainability, and environmental protection. [ABSTRACT FROM AUTHOR]

An investigation into families of integrals containing powers of the arctanh and log functions will be undertaken in this paper. It will be shown that Euler sums play an important part in the solution of these integrals. In another special case we prove that the corresponding log-tanh integral can be represented as a linear combination of the product of zeta functions and the Dirichlet eta function. [ABSTRACT FROM AUTHOR]

Contamination of soil by heavy metals severely affects plant growth and causes soil pollution. While effects on plant growth have been investigated for metals taken individually or in groups, less is known about their comparative effects. In this study Arabidopsis thaliana seedlings were grown for 14 days in Petri dishes containing medium contaminated by six common heavy metals (Hg, Cd, Pb, Cu, Ni and Zn), at the minimum concentrations defined as toxic by the most recent EU legislation on contamination of agricultural soils. (a) Root structure and morphology, (b) metal composition and translocation, and (c) the levels of indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) were analyzed. Metals accumulated more in roots than in shoots, with concentrations that differed by several orders of magnitude depending on the metal: Cd (ca. 700 × and ca. 450 × in roots and shoots, respectively), Hg (150 × , 80 ×), Ni (50 × , 20 ×), Cu (48 × , 20 ×), Zn (23 × , 6 ×), and Pb (9 × , 4 ×). Responses were significant for at least nine of the ten root parameters (with the exception of Hg), and five of the six shoot parameters (with the exception of Zn). Cu and Zn induced respectively the strongest responses in root hormonal (up to ca. 240% the control values for IBA, 190% for IAA) and structural parameters (up to 210% for main root length, 330% for total lateral root length, 220% for number of root tips, 600% for total root surface, and from 2.5° to 26.0° of root growth angle). Regarding the shoots, the largest changes occurred for shoot height (down to 60% for Ni), rosette diameter (down to 45% for Hg), leaf number (up to 230% for Zn) and IBA (up to 240% for Pb and Cu). A microscope analysis revealed that shape and conformation of root hairs were strongly inhibited after Cd exposure, and enhanced under Hg and Pb. The results could have positive applications such as for defining toxicity thresholds (in phytoremediation) and acceptable concentration levels (for policies) for some of the most common heavy metals in agricultural soils. • Responses of Arabidopsis to six of the most common heavy metals were studied. • Root-shoot structure, morphology and auxins levels were measured and analyzed. • A strong and specific remodelling of the shoot and root in response to metals occurred. [ABSTRACT FROM AUTHOR]

An investigation into the representation of integrals involving the product of the logarithm and the arctan functions, reducing to log-tangent integrals, will be undertaken in this paper. We will show that in many cases these integrals take an explicit form involving the Riemann zeta function, the Dirichlet eta function, Dirichlet lambda function and many other special functions. Some examples illustrating the theorems will be detailed. [ABSTRACT FROM AUTHOR]

In the past decade learning outcomes in public basic schools in Ghana have fallen far below the targets of the Ministry of Education as less than a third of primary school children reach proficiency in English or in Mathematics. In the wake of this low performance, there has been a call for the professionalization and strengthening of instructional leadership in Ghanaian basic schools to facilitate effective teaching and learning. Employing qualitative research strategy through interviews, this study sought to investigate instructional leadership practices of 14 school leaders in the basic schools of one educational district of Ghana. The study found limited shared instructional leadership aimed at improving instruction. It seems instructional leadership was related to managerially focused idiosyncratic teaching and learning practices underpinned by behaviourism. Head Teachers had entrenched a leadership culture driven by central policies and expectations. [ABSTRACT FROM AUTHOR]

An investigation into a family of definite integrals contain- ing log-polylog functions will be undertaken in this paper. It will be shown that Euler sums play an important part in the solution of these integrals and may be represented as a BBP-type formula. In a special case we prove that the corresponding log integral can be represented as a linear combination of the product of zeta functions and the Dirichlet beta function. [ABSTRACT FROM AUTHOR]

Introduction: medical staff in constant handling of cytostatics is exposed to various levels of respective drugs toxicity. The exposure route is: inhalation, intradermal and oral. Symptoms of toxic effects vary in length of exposure, type of drug, and route of exposure. Protective equipment at work with toxic substances is the basis of work, and all risks are exclusively related to non-compliance with safety procedures and insufficient preventive measures. Aim of the study: to examine the management of cytostatics safety, to determine the quality of work of the examined group of medical staff, to prove the persistence of harmful effects of cytostatics on medical staff and quality and efficiency of all nurses in the process of chemotherapy. Materials and methods: this is a retrospective, cohort, clinical-descriptive study, research was conducted at Clinic of Hematology, Clinic of Oncology, and Clinic of Tuberculosis and Lung Diseases of the Clinical Center University of Sarajevo in the period from January 1st to 31st December 2015. Data were collected on a voluntary basis and anonymously, using a questionnaire on the quality of safety in working with toxic substances. The study included 50 nurses of all professional profiles (nurses with completed secondary nursing school, senior nurses and graduate nurses), who have in the course of their work applied cytotherapy over a period of 1-20 years. Results: the study justified its research goal and proved inadequate and insufficient protection at work with toxic substances, malfunctions in the preparation and use of drugs in the work of healthcare providers, and the existence of harmful effects of cytostatics on healthcare providers, with 111 toxic effects in 39 subjects. Conclusion: the study was conducted on 50 respondents proved the existence of toxicity in cytostatic handling. Results of the study proved justification of establishing a centralized unit for preparation of cytostatic agents (CPC). [ABSTRACT FROM AUTHOR]

Finally, people with celiac disease can tolerate sourdough-produced bread much more easily than bread made of the same ingredients but fermented with another type of yeast (Gobbetti I et al. i [10]). The rise in Covid-19 infections and the consequent social isolation have led to a widespread surge in interest in home baking, particularly of sourdough breads. Sourdough, also called acid yeast or natural yeast, is on the other hand obtained from a mixture of flour and water that absorbs yeast strains that are free in the air or present in the flour. Today, we think of sourdough as a special type of bread but before the advent of commercial yeast sourdough was the only way bread was made (Harris [15]). [Extracted from the article]

There is little information regarding factors that determine dietary diversity among pregnant women in Ghana. The present study, therefore, sought to assess the independent predictors of dietary diversity and its relationship with nutritional status of pregnant women in the Northern Region of Ghana. The present study was an analytical cross-sectional survey involving 423 pregnant women in different stages of gestation. The 24-h dietary recall method was used to assess minimum dietary diversity for women (MDD-W), and nutritional status was assessed using mid-upper arm circumference (MUAC) measurements. Binary logistic regression was performed to assess the association between maternal dietary diversity and maternal thinness and a P value of <0⋅05 was considered statistically significant. Of the 423 women, 79⋅9 % (95 % CI 76⋅1, 83⋅7) met the MDD-W and the prevalence of undernutrition among the pregnant women was 26⋅0 %. The analysis showed that women of low household wealth index were 48 % less likely (AOR 0⋅52, CI 0⋅31, 0⋅88) of meeting the MDD-W, whereas women from households of poor food insecurity were 88 % less likely (AOR 0⋅12, CI 0⋅05, 0⋅27) of achieving the MDD-W. Women of low household size were three times more likely of meeting the MDD-W (AOR 3⋅07, CI 1⋅13, 8⋅39). MDD-W was not associated with maternal underweight during pregnancy. In conclusion, the results of the present study showed that food insecurity and not low MDD-W, associated with mothers' thinness (underweight) during pregnancy in peri-urban setting of Northern Ghana. [ABSTRACT FROM AUTHOR]

We evaluate Euler-like sums involving harmonic numbers using expansions for powers of logarithmic, arctan and a r c t a n h functions. [ABSTRACT FROM AUTHOR]

In this article, we present the measurements and a physically motivated model for the transport and diffusion of small charge packets in the bulk of thick high-resistivity charge-coupled devices (CCDs). We use a novel technique to measure the lateral spread of the charge as a function of the ionization depth in the silicon bulk. Measurements from CCDs, currently being used in several scientific instruments, are shown and used to validate the new mathematical algorithm that extends the current modeling of the diffusion of the charge carriers in silicon before being collected by the pixel potential wells. [ABSTRACT FROM AUTHOR]

We calculate the photoelectron spectrum of small mono-niobium carbide clusters (NbCn) using density functional theory for clusters with n = 2-7 and the symmetry adapted cluster configuration interaction method for the smallest clusters (n = 2-4). Theoretical spectra of a single structure cannot explain all peaks present in the spectrum measured by Zhai et al. [J. Chem. Phys. 115, 5170 (2001)]. However, we can match all peaks in the experimental spectra if we assume that the beam contains a combination of cyclic and linear structures. This finding is even more surprising given the fact that some of the excited metastable geometries have energies as large as 0.5 eV above the ground state. Our result is confirmed by both theoretical approaches. We suggest further experiments, using additional beam cooling, to corroborate this observation. [ABSTRACT FROM AUTHOR]

The van der Waals (dispersion) interaction between an atom and a cluster or between two clusters at large separation is calculated by considering each cluster as a point particle, characterized by a polarizability tensor. For the extreme limit of very large separation, the fully retarded regime, one needs to know just the static polarizability in order to determine the interaction. This polarizability is evaluated by including all many-body (MB) intracluster atomic interactions self-consistently. The results of these calculations are compared with those obtained from various alternative methods. One is to consider each cluster as a collection of many atoms and evaluate the sum of two-body interatomic interactions, a common assumption. An alternative method is to include three-body atomic interactions as a MB correction term in the total energy. A comparison of these results reveals that the contribution of the higher-than-three-body MB interactions is always attractive and non-negligible even at such a large separation, in contrast to common assumptions. The procedure employed is quite general and is applicable, in principle, to any shape or size of dielectric cluster. We present numerical results for clusters composed of atoms with polarizability consistent with silica, for which the higher-than-three-body MB correction term can be as high as 42% of the atomic pairwise sum. This result is quite sensitive to the anisotropy and orientation of the cluster, in contrast to the result found in the additive case. We also present a power law expansion of the total van der Waals interaction as a series of n-body interaction terms. [ABSTRACT FROM AUTHOR]

van der Waals interactions between nanoclusters have been calculated with a self-consistent, coupled dipole method. The method accounts for all many-body (MB) effects. Comparison is made between the exact potential energy, V, and the values obtained with two alternative methods: the sum of two-body interactions and the sum of two-body and three-body interactions. For all cases considered, the three-body term alone does not accurately represent the MB contributions to V. MB contributions are especially large for shape-anisotropic clusters. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV) is a component of the solar radiation with a wavelength in the range of 100 ≤ λ ≤ 390 nm that is almost entirely shielded by the terrestrial atmosphere, but not in space. The effects of UV-C (100 ≤ λ ≤ 280 nm) on plants mainly depend on: i) the applied UV-C radiation dose and quality, ii) the different plant species and varieties used, and iii) the phenological phase of irradiated plants. UV-C radiation can be extremely dangerous also at low exposition times. On the other side, considering that terrestrial plants under sunlight are naturally exposed to low doses of UV-C, the question is how much UV-C could be beneficial for plants cultivated in space, in relation to i) protection of plants from pathogens, ii) increase of the concentration of important dietary supplements, and iii) regulation of some physiological processes. The research on UV-C should be more addressed to better evaluate the damages and benefits in UV-C-exposed photosynthetic organisms, involving plants useful for Bioregenerative Life Support Systems (BLSSs). [ABSTRACT FROM AUTHOR]

In this paper we develop new identities for Euler sums with rational argument. We shall investigate and report on new Euler identities of weight for m,p,q positive integers and m + p + q an even integer, but with a non-unitary argument of the harmonic numbers. Some examples of these Euler identities will be given in terms of Riemann zeta values, Dirichlet values and other special functions. We shall also give an explicit solution to an integral with a log polylog integrand. [ABSTRACT FROM AUTHOR]

Many countries in Sub-Saharan Africa have used non-traditional teacher education programs to address the perpetual problem of inadequate provision of trained teachers. Using the bioecological systems theory, the present study examined untrained teacher trainees' perceptions about the prospects and challenges of upgrading untrained teachers in Ghana. Participants included 248 untrained teachers (39.4% males, 60.6% females) enrolled in the Untrained Teachers Diploma in Basic Education (UTDBE) program at two colleges of education in the Northern Region of Ghana. A 5-point Likert questionnaire consisting of nine predictors served as the main data source. The predictors were: attitude, program cost, admission requirements, autonomy support, self-efficacy, social support, childcare, curriculum and instruction, and political interference. The questionnaire also elicited the following demographic information: teaching experience, year in program, grade level taught, level of education attained, age, trainees' sex, and marital status. The response variable was the extent to which the UTDBE was achieving its goals. The questionnaire had a Cronbach's alpha of .728. The lasso-penalized logistic regression model was used to determine important predictors of the response variable. Overall, 90.72% of the trainees indicated the program was achieving its goals to some degree. The optimal predictive model identified four (4) important predictors: self-efficacy, social support, attitude, and autonomy support in descending order of importance in terms of the extent to which the program was achieving its goals. In conclusion, individual factors, trainees' direct environment, and autonomy-supportive teacher education classrooms influenced untrained teacher trainees' perceptions of the extent to which their teacher education program was achieving its goals. [ABSTRACT FROM AUTHOR]

In conventional olive growing, frequent soil tillage strongly reduces the complexity and diversity of the agro-ecosystem. Here, a metabolomic analysis was carried out on the xylem sap (XS) of olive plants (Olea europaea L.) from a grove located in Southern Italy (Basilicata region). The orchard has been divided in two plots that have been managed for 18 years with two different systems: a) 'sustainable management' (S mng), with no-tillage, fertigation and internal C-inputs (spontaneous weeds and pruning residues), and b) an adjacent rainfed 'conventional management' (C mng), that included soil tillage and mineral fertilization. The XS was extracted from olive shoots in two sampling times (ST1: May; ST2: October) using a Sholander pressure chamber, and its metabolome analyzed by ultra-high performance liquid chromatography (UHPLC) coupled to a hybrid quadrupole-time-of-flight mass spectrometer (QTOF-MS). The discriminating compounds were 94 at ST1 and 119 at ST2, and 35 of them were in common between the two sampling times. The majority of the discriminating metabolites (73 on 94 at ST1, and 109 on 119 at ST2) were found at higher concentration in the XS of S mng plants, compared to that of C mng ones. Most of the discriminating metabolites found in XS (about 80%, both at ST1 and ST2) were involved in plant secondary metabolism, mainly for plant chemical defense, growth regulation and signal transduction. The most prevailing class of compounds included terpenoids, phytohormones, alkaloids, sterols/steroids, retinols/retinoids, tocopherols and carotenoids. For the first time, we have demonstrated that the XS of a tree crop significantly responds to a shift of soil management. Generally, the plants of the S mng plot showed an up-regulated secondary metabolism. The results of our study encourage the use of a set of sustainable agricultural practices in a productive orchard, in order to enhance plant physiological status, increase yield quantity/quality, safeguard the environment and ameliorate human health. • Olive plants were managed by a sustainable (S mng) or a conventional (C mng) system. • A metabolomic analysis (UHPLC/QTOF-MS) of extracted xylem sap was conducted. • Deep differences in xylem sap composition were observed between S mng and C mng. • The plants from the S mng showed an up-regulated secondary metabolism. • The xylem sap of olive trees responded to a shift of soil management. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A sustainable (S mng) and a conventional (C mng) olive orchard were compared. • Pedological, chemical, and microbiological analyses on soils were carried out. • S mng showed a higher soil C and N in the topsoil layers, and lower pH. • N-cycling bacteria were higher in S mng but bacterial diversity did not change. • A new sustainable approach for optimizing soil C and N cycling is proposed. Abstract Under Mediterranean type climates, a sustainable soil management aimed at increasing soil organic carbon and microbiological diversity is of key importance. The aim of this study was to characterize and compare soils from a mature Mediterranean olive (Olea europaea L.) orchard subjected to two different soil management systems (sustainable, S mng , and conventional, C mng) for 18 years. Composite soil samples were analyzed qualitatively (pedological determinations) and quantitatively (soil C, N and pH). Bacterial metabolic activity and diversity were evaluated spectrophometrically by the Biolog® assay, while 16S-based metagenomics analysis was used to analyse the abundance of N-cycling bacteria. From the general analysis of the data obtained by the study of soil profiles and litter, C and N dynamics, and the genetic and functional diversity of soil bacteria, it emerged that the S mng system caused an improvement in soil organic matter in the topsoil layers, compared to the C mng system, with consequent increases in the abundance of soil N-cycling bacteria but without affecting the indices related to total bacterial metabolic activity and diversity. The results obtained could promote the development of new approaches for optimizing soil carbon cycling, managing nutrient transport, and sustaining and improving olive yield and quality. [ABSTRACT FROM AUTHOR]

Presents information on thermionic cooling, a proposed method of refrigeration and power generation. Physics behind thermionic cooling; How cooling is obtained; Theory of the properties of a multilayer thermionic refrigerator and power generator.

Discusses a study which detailed the calculation of the conductivity, Hall coefficient, and thermopower of Hg[sub1-x]Cd[subx]Te (MCT) for 0≤x≤0.3. Methods used; Agreement considered excellent for bulk samples and thick films grown by molecular-beam epitaxy; Band gap of suitable materials for thermoelectric applications; Condition in which the energy band gap of MCT changes.

Abstract Under suitable conditions, low-quality, treated urban wastewater (TWW) is an additional water resource for irrigation in water-scarce environments but its use in agriculture requires a careful monitoring of a range of hygiene parameters, including human pathogenic bacteria (HPB). DNA-based microbiological analyses on soil, xylem sap, and leaves surface (phyllosphere) were carried out in an olive (Olea europaea L.) grove located in Southern Italy (Basilicata region). The experimental grove has been managed in two plots for 18 years. The experimental plot (WW tr) was drip irrigated daily with TWW (2800 m3 ha−1 year−1), while the control plot (RF tr) was rainfed. The results of the 16S-rRNA-based metagenomic analysis demonstrated that the phyllosphere had the lowest number of potential HPB (6), compared to soil (22) and xylem (26) compartments. Gammaproteobacteria, including potential HPB, like Pseudomonas and Acinetobacter spp., were significantly higher in WW tr soil and xylem sap, compared to RF tr. A similar trend was observed for Burkholderia spp. (Betaproteobacteria) and Mycobacterium spp. (Actinobacteria). The Firmicutes Enterococcus , Staphylococcus and Streptococcus spp. were more abundant in WW tr xylem sap. The pathogenic Clostridium perfringens was found higher on WW tr leaves (relative abundance 7.17 in WW tr and 1.33 in RF tr) and Enterococcus faecalis in WW tr xylem sap (93.22 in WW tr and 7.08 in RF tr). On the basis of the results obtained, the irrigation with TWW can be considered a realistic and safe agronomic practice in Mediterranean orchards, and an opportunity for farmers and consumers. Graphical abstract Unlabelled Image Highlights • Treated urban wastewater (TWW) can contain human pathogenic bacteria (HPB). • A TWW-irrigated (WW tr) and a rainfed (RF tr) olive orchard were compared. • 16S-rRNA-microbiological analyses on soil, xylem sap, and phyllosphere were done. • WW tr soil contained more potential HPB than xylem sap and phyllosphere. • Urban TWW, if adequately-treated and applied, does not constitute health risks. [ABSTRACT FROM AUTHOR]

In Ghana, research has shown that educational reforms over the years have ignored the importance of school leadership development, and there are currently very few reform initiatives that address the need to develop the leadership proficiencies and skills of school leaders. This study sought to investigate how school leaders, who include headteachers, assistant headteachers, and form masters, in such contexts develop their leadership skills following their appointment into their new roles. A mixed-methods approach was employed in gathering both quantitative and qualitative data concurrently from three groups of leaders in the basic schools of one rural educational district in Ghana. Results from the study showed that the professional development activities (PDAs) that the leaders employed for their development were mostly informal and self-directed learning methods. There were only limited formal leadership development programmes for the leaders working within any of the rural district basic schools represented in the study. The study concludes that to strengthen school leadership in basic schools in the selected district, educational authorities would need to learn from international best practice to initiate sustainable PDAs to strengthen the leadership capacities of leaders to promote effective teaching and learning in schools. [ABSTRACT FROM AUTHOR]

The post-management of landfills represents an important challenge for landfill gas treatment. Traditional systems (energy recovery, flares, etc.) present technical problems in treating flow with low methane (CH4) concentrations. The objective of this study was to isolate methanotrophic bacteria from a field-scale biofilter in order to study the bacteria in laboratories and evaluate the environmental factors that mostly influence Microbial Aerobic Methane Oxidation (MAMO). The soil considered was sampled from the biofilter located in the landfill of Venosa (Basilicata Region, Italy) and it was mainly composed of wood chips and compost. The results showed that methanotrophic microorganisms are mainly characterized by a slow growth and a significant sensitivity to CH4 levels. Temperature and nitrogen (N) also have a very important role on their development. On the basis of the results, biofilters for biological CH4 oxidation can be considered a viable alternative to mitigate CH4 emissions from landfills. [ABSTRACT FROM AUTHOR]

We develop new closed form representations of sums of cubic alternating harmonic numbers and reciprocal binomial squared coefficients. [ABSTRACT FROM AUTHOR]

A screening strategy using micropropagation glass tubes with a gradient of distances between germinating seeds and a metal-contaminated medium was used for studying alterations in root architecture and morphology of Arabidopsis thaliana treated with cadmium (Cd) and zinc (Zn) at the concentration of 10–20 μM and 100–200 μM, respectively. Metal concentrations in plant shoots and roots were measured by quadrupole inductively coupled plasma mass spectrometry. After 21 days from germination, all plants in the tubes were scanned at high resolution and the root systems analyzed. The localization of indole-3-acetic acid (IAA) in the primary root and lateral root apices was monitored using DR5:GUS , LAX3:GUS and AUX1:GUS Arabidopsis transgenic lines. Total phenol content in leaves was measured spectrophotometrically. Shoot and root dry weight and leaf area did not change in Zn-exposed plants and significantly decreased in Cd-exposed plants, compared to control plants. Cadmium induced a reduction of root length, of mean number of roots and of total root surface. Both Cd- and Zn-exposed plants showed a reduced specific root length. This morphological behavior, together with an observed increase in root diameter in metal-exposed plants could be interpreted as compensatory growth, and the observed thicker roots could act as a barrier to protect root from the metals. In comparison with the apical localization of the IAA signal in the control plants, Zn generally reinforced the intensity of IAA signal, without affecting its localization. In Cd-exposed plants, IAA localization remained apical but weaker compared to control plants. Total phenols decreased in plants exposed to Zn and Cd. Therefore, we propose that the remodelling of the root architecture and the production of some secondary metabolites, such as IAA and phenols could be two responses of plants subjected to metal stress. This knowledge can open the way to future phytoremediation strategies of contaminated sites. [ABSTRACT FROM AUTHOR]

We introduce an integral transform which may be used to construct new closed-form formulas for series involving alternating harmonic numbers, such as the Ramanujan-like formulaintroduced in this article which elegantly relates Catalan's constantGwiththrough an infinite summation involving Catalan numbers. Using this integral transform, we also obtain closed-form expressions for new series involving harmonic numbers of even index such as the new summationfor Apéry's constant introduced in our article, as well as new proofs of known formulas for series containing harmonic numbers. The techniques introduced in this paper are also used to provide closed-form evaluations for some new definite integrals which state-of-the-art computer algebra systems cannot compute symbolically. [ABSTRACT FROM AUTHOR]

Sum Frequency Generation (SFG) is a powerful, surface-specific vibrational probe ideally suited to studying buried interfaces; however, insight from theory is often necessary to explain the microscopic origins of the spectral features. To calculate the SFG spectrum at an insulating solid/liquid interface, we develop a flexible polarizability model that takes local dipole interactions into account, rather than assuming additive polarizabilities. We use this model to calculate bond dipoles and polarizabilities that reflect the local geometry of the interface. We apply our method to the Al2O3(0001)-H2O interface, where we reproduce the experimental spectrum and show the two H stretching peaks come from solvent and surface modes separately, not from H2O molecules with different coordination numbers as previously thought. Our work therefore emphasizes the importance of treating both surface and solvent at the same level of theory for accurate spectroscopic calculations. [ABSTRACT FROM AUTHOR]

In this paper we consider a master integral in four arbitrary parameters. The integrand involves the logarithmic function and the Gauss hypergeometric function, which in certain special cases the integral reduces to identities involving zeta functions. A relationship will also be created between the integral and Euler sums of arbitrary order and arbitrary argument. Many interesting new specific examples will be highlighted. [ABSTRACT FROM AUTHOR]

Focuses on a study on the thermoelectric figure of merit of n-Hg[sub1-x]Cd[subx]Se. Introduction ot the thermal conductivity of solids; Description of the model; Results and conclusions.

Conventional medicines used to treat obesity and cancer frequently exhibit high side effects, so that researchers are focusing on new therapies and drugs based on natural products. Total extracts from bulbs of Muscari comosum were tested for i) free radical scavenging activity, ii) in vitro enzymatic inhibition of pancreatic α-amylase and lipase, and iii) inhibition of the growth of breast adenocarcinoma cells. Three treatments were considered: bulbs boiled in water for 15 min (traditional cooking method; BB); bulbs steam-cooked for 15 min (alternative cooking method; SB); raw bulbs (RB). The polyphenol content and antioxidant capacity of bulb extracts were related to the inhibition of pancreatic lipase and α-amylase, whose activities have been found to have a half maximal inhibitory concentration (IC50) of 0.28, 2.14 and 3.22 mg/mL for lipase, and 0.16, 0.73 and 0.69 mg/mL for α-amylase in RB, SB and BB, respectively. The analysis on breast adenocarcinoma MCF-7 cells revealed that RB extracts, and in a lesser extent BB, exerted a dose-dependent inhibition on cell proliferation. Considering that the potential of natural products for the treatment of obesity are under exploration, M. comosum could be an excellent plant for the development of future anti-obesity drugs, also able to prevent cancer. [ABSTRACT FROM AUTHOR]

Ultraviolet-C (UV-C) light (100 ≤ λ ≤ 280 nm) is a ionizing radiation that can damage living organisms. An experiment was conducted on plants of common dandelion (Taraxacum officinale Weber, T. Densleonis Desf.) and purple coneflower [Echinacea purpurea, (L.) Moench] irradiated with UV-C at different exposition times, under controlled conditions and grown in self-produced characterized compost, to assess the effect of different doses UV-C radiation on some physiological parameters. Trials have been carried out using a black chamber equipped with an UV-C lamp in which plants were divided in four groups on the basis of UV-C irradiation period (10, 30, 60, and 120 min). Non-irradiated plants were kept as controls. Plant photosynthetic performance, chlorophyll content (SPAD) and some morphologic traits were recorded before, immediately after irradiations and 20 days weeks later. The effects on photosynthetic performances and chlorophyll contents (SPAD) were evaluated and compared with data obtained in similar experiments where tomato plants were irradiated at different times with UVC light. In both species, SPAD values decreased as the irradiation period became longer. The two species showed different gas exchange dynamics, depending on the UV-C exposure time. Two months after the UV-C irradiation, plant dry weight measured at 120-min UV-C exposure was significantly lower than the control. [ABSTRACT FROM AUTHOR]

Introduction: Diffuse Large B-cell Lymphoma (DLBCL) is the most commonly represented subtype of Non-Hodgkin Lymphoma (NHL), accounting for 30% - 58% of newly diagnosed. Immunochemotherapy is considered a standard treatment in first line therapy. International Prognostic Index (IPI) which includes: age, level of serum lactate dehydrogenase (LDH), general condition of the patient, clinical stage and extranodal involvement, oers a possibility of recognizing patients with expected poor outcome. Aim: to prove predictive value of the International Prognostic Index in DLBCL patients in the era of immunochemotherapy in relation to achieving first complete remission and three-year survival. Material and methods: the conducted research is a retrospective analysis of DLBCL patients' treatment results in the era of immunochemotherapy. The research included 46 patients (32 women and 14 men) aged from 24 to 74 years, with median age 52 years, most of them diagnosed between 50 to 60 years of age. Results: results of the research indicated statistically significant influence of IPI>2 in achieving first complete remission in patients treated in first line by immunochemotherapy (p=0.028). 66% of the examinees with a high IPI score (3, 4, and 5) did not achieve complete remission in the first line of immunochemotherapy. Three-year survival in participants who achieved complete remission in relation to primarily progressive disease and early relapse is significantly dierent (p< 0. 0005). IPI>2 was in correlation with three-year survival of the participants (p=0.0447). In the participant group with IPI>2, patients survive up to 30 month s (p=0.008; Kaplan Meier survival curve). Statistics: assessment of the significance of dierences (X2 tests), Log Rank (Mantel-Cox) test, Kaplan-Meier curve of survival. Conclusion: although established in the era before immunochemotherapy, IPI remains the most important and the cheapest clinical tool in the management of DLBCL patients. [ABSTRACT FROM AUTHOR]

Introduction: European Treatment and Outcomes Study (EUTOS) score divides patients with chronic myeloid leukemia (CML) into low and high risk groups. Aim: to reevaluate predictor significance of EUTOS score in relation to achieving event free survival (EFS): acceleration/blast transformation or death, major molecular response (MMR) and 10-year overall survival of CML Ph+. Material and methods: this was a retrospective study, following CML Ph+ patients in the period from 2001 to 2014. The study involved 48 patients aged 18 to 60 years, mean age 44.6 years, of which 26 (54%) males and 22 females (46%). There were 24 patients in a low risk group and 24 in a high risk group, who were treated with Tyrosine kinase inhibitors (TKI) in the first, second and third line of therapy. Results: it was confirmed that MMR response at 3 to 6 months depends of EUTOS score (low vs. high) 64.3% vs 20% p=0.014; and at 18 months 66.7% vs 20%, p=0.013. Median survival in the low score group was 134.5 months, specifically 95% CI (110.5-158.6), which was longer than in the high score group in which median survival was 102.7 months or 95% CI (79.4-126). Survival rate differences without EFS in the low and high risk groups of EUTOS score were dependent χ²=4.463, p=0.035. Difference in survival according to EUTOS score was not statistically significant χ²=2.49, p=0.114. Conclusion: EUTOS score was not predictive for outcome in 10 years overall survival, but had predictive achieving EFS, value in MMR at 3 to 6 months and at 18 months. Statistic analysis: assessment of the significance of differences (X² tests), Log Rank (Mantel-Cox) test, Kaplan-Meier curve of survival. [ABSTRACT FROM AUTHOR]

Half integer values of harmonic numbers and reciprocal binomial coefficients sums are investigated in this paper. Closed-form representations and integral expressions are developed for the infinite series. [ABSTRACT FROM AUTHOR]

LAGO is an extended cosmic ray observatory composed of water-Cherenkov detectors (WCD) placed throughout Latin America. It is dedicated to the study of various issues related to astrophysics, space weather and atmospheric physics at the regional scale. In this paper we present the design and implementation of the front-end electronics and the data acquisition system for readout of the WCDs of LAGO. The system consists of preamplifiers and a digital board sending data to a computer via an USB interface. The analog signals are acquired from three independent channels at a maximum rate of ~1.2×10 5 pulses per second and a sampling rate of 40 MHz. To avoid false trigger due to baseline fluctuations, we present in this work a baseline correction algorithm that makes it possible to use WCDs to study variations of the environmental radiation. A data logging software has been designed to format the received data. It also enables an easy access to the data for an off-line analysis, together with the operational conditions and environmental information. The system is currently used at different sites of LAGO. [ABSTRACT FROM AUTHOR]

The present paper aims to investigate phenolic profiles, antioxidant capacity and mineral composition of lettuce ( Lactuca sativa L., var. ‘Maravilla de Verano’) grown under conventional (CON) and an organic (ORG) systems with four different fertilization treatments. The polyphenolic profiles of leaf extracts were determined by ultra-high-performance liquid chromatography (UHPLC), the levels of mineral elements by means of inductively coupled plasma mass spectrometry, whereas total phenolic content and antioxidant capacity were determined spectrophotometrically. Yield, soil and meteorological parameters were measured. In all the fertilization treatments, total phenolic acids and flavonols in CON were significantly higher compared to ORG. A trend parallel to that of single phenols was observed for total phenolic content and total antioxidant capacity. Plant mineral distribution revealed significant changes between CON and ORG systems in some plant macronutrients (N, Mg, S, Na, Fe) and micronutrients (Se, Mn, Mo). The differences among fertilization treatments for all the parameters considered were also discussed. From the overall analysis of the results, the higher content of phenolics observed in CON system could be associated to the presence of more stressful conditions, in terms of plant and/or soil mineral deficits. On the other hand, the adoption of an organic management determined higher yields and a better plant mineral balance. [ABSTRACT FROM AUTHOR]

Background: Plants mediate several defense mechanisms to withstand abiotic stresses. Several gene families respond to stress as well as multiple transcription factors to minimize abiotic stresses without minimizing their effects on performance potential. RNA helicase (RH) is one of the foremost critical gene families that can play an influential role in tolerating abiotic stresses in plants. However, little knowledge is present about this protein family in rapeseed (canola). Here, we performed a comprehensive survey analysis of the RH protein family in rapeseed (Brassica napus L.). Results: A total of 133 BnRHs genes have been discovered in this study. By phylogenetic analysis, RHs genes were divided into one main group and a subgroup. Examination of the chromosomal position of the identified genes showed that most of the genes (27%) were located on chromosome 3. All 133 identified sequences contained the main DEXDC domain, the HELICC domain, and a number of sub-domains. The results of biological process studies showed that about 17% of the proteins acted as RHs, 22% as ATP binding, and 14% as mRNA binding. Each part of the conserved motifs, communication network, and three-dimensional structure of the proteins were examined separately. The results showed that the RWC in leaf tissue decreased with higher levels of drought stress and in both root and leaf tissues sodium concentration was increased upon increased levels of salt stress treatments. The proline content were found to be increased in leaf and root with the increased level of stress treatment. Finally, the expression patterns of eight selected RHs genes that have been exposed to drought, salinity, cold, heat and cadmium stresses were investigated by qPCR. The results showed the effect of genes under stress. Examination of gene expression in the Hayola #4815 cultivar showed that all primers except primer #79 had less expression in both leaves and roots than the control level. Conclusions: New finding from the study have been presented new insights for better understanding the function and possible mechanism of RH in response to abiotic stress in rapeseed. [ABSTRACT FROM AUTHOR]

Among the different causes of gynecological acute pelvic pain, ovarian torsion represents a surgical emergency. It is a rare case in the pediatric/adolescent aged group that must be included in the differential diagnosis of any girl with abdominal pain or pelvic/abdominal mass. Current recommendations suggest that laparoscopic detorsion should be performed in order to preserve the integrity of the ovaries and fertility, although oophoropexy may be considered in case of severe necrosis. Nevertheless, maintaining the circulation of the ovary after detorsion deteriorates the tissue injury and leads to a pathologic process called ischaemia/reperfusion (I/R) injury, which is characterized by oxidative stress. During the detorsion process, an excess amount of molecular oxygen is supplied to the tissues, and reactive species of oxygen (ROS) such as superoxide radical (O2 -), hydrogen peroxide (H2O2), hydroxyl radical (OH•), as well as reactive nitrogen species (RNS) are produced in excess. ROS, RNS and their toxic products cause DNA damage and lipid peroxidation in the cellular and mitochondrial membranes, leading to cell death. In spite of attention on this topic, currently there is no shared and clear evidence about the use of anti-inflammatory and antioxidant agents to prevent I/R damage after laparoscopic ovarian detorsion. Considering this element, future research should aim to develop shared protocols for the clinical use (route of application, dosage and time of application) of antioxidants after laparoscopic management of this condition. [ABSTRACT FROM AUTHOR]

Artificial light, supplied by fluorescent lamps, has been effectively utilized in controlled- environment chambers for horticulture and floriculture nursery. This experiment aimed at investigating whether light-emitting diodes (LEDs) have the same effectiveness on plant morphology, photosynthetic and physiological responses as FLUORA lamps. Seedlings of common dandelion (Taraxacum officinale) and purple coneflower (Echinacea purpurea), species of high interest for their nutraceutical properties, were grown in controlled-environment chambers for 50 days under LED and FLUORA light sources as sole-source lighting systems, and the effects of artificial light supplies on plant photosynthetic performance and chlorophyll content (SPAD) were evaluated. The results were compared to plants grown under natural sunlight. In both species, total chlorophyll content (SPAD) values decreased for plants under sunlight, and for those grown under FLUORA lighting throughout the experimental period, while the values measured for plants grown under LEDs maintained a relatively constant value. At the end of the experiment, plant dry matter in both species was significantly lower under LEDs and FLUORA lighting, than the plants exposed to solar light. The two species showed different gas exchange dynamics under LEDs and FLUORA lighting, and photosynthetic performance decreasing after 10 days of light treatment compared to plants under sunlight. The results demonstrated that for common dandelion and purple coneflower photosynthetic processes are often modified when the species are cultivated under these artificial lighting and in controlled- environment chambers, because lamps do not able to generate the same spectrum and energy of sunlight. [ABSTRACT FROM AUTHOR]