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Polythiourethanes (PTU) and polythioesters (PTE) derived from renewable sources are emerging sustainable polymers for their excellent degradability and recyclability. However, P(TU-alt-TE) copolymers have been rare and challenging to synthesize. Here, we report the efficient synthesis of novel P(TU-alt-TE) copolymers via the alternating copolymerization of N-thiocarboxyanhydrides (NTA)/episufides (ES) and provide mechanistic insight into the alternating chain propagation process via density functional theory (DFT) calculation. The incorporation of ESs into traditional peptide backbone is capable of adjusting the glass transition temperature below thermal decomposition temperature, which confers better thermal processability by regulating the rigidity of the backbone and the hydrogen bond interaction among the polymer chains. Crosslinked PTUs with tailored properties are accessible by altering the feeding ratio of NTAs and (bifunctional) ESs. Moreover, the thiourethane in the backbone can endow interesting underwater adhesion properties to the materials. Considering the broad scope of NTA and ES monomers, this method is expected to provide a promising and general route to a wide range of P(TU-alt-TE) copolymers with diverse properties. [ABSTRACT FROM AUTHOR]

In this paper, algorithms for different types of trigonometric power sums are developed and presented. Although interesting in their own right, these trigonometric power sums arise during the creation of an algorithm for the four types of twisted trigonometric power sums defined in the introduction. The primary aim in evaluating these sums is to obtain exact results in a rational form, as opposed to standard or direct evaluation, which often results in machine-dependent decimal values that can be affected by round-off errors. Moreover, since the variable, m, appearing in the denominators of the arguments of the trigonometric functions in these sums, can remain algebraic in the algorithms/codes, one can also obtain polynomial solutions in powers of m and the variable r that appears in the cosine factor accompanying the trigonometric power. The degrees of these polynomials are found to be dependent upon v, the value of the trigonometric power in the sum, which must always be specified. [ABSTRACT FROM AUTHOR]

Introduction. The aim of this research was to study the effect of alternating impulses of pressure on changes in the physicochemical properties of liquid nutrient solutions and media for hydroponic systems used in food production. Materials and methods. Liquid nutrient solutions such as double distilled water, irrigation water for drip irrigation systems, and solutions with fertilizes were used for processing. Spring barley "Myronivskyi 22" and vigorous triticale "Soncedar kharkivskyi" were used for testing growing crops. Rotary-pulsed apparatus of the cylindrical type with clearances 120×10-6 m was used. The method of testing growing crops and method of optical microscopy were used. Results and discussion. For growing of spring barley "Myronivskyi 22" such parameters were selected: processing time - 30 s, processing frequency 5, angular velocity - 315 s-1, impulses of pressure - 390 kPa. For growing of vigorous triticale "Soncedar kharkivskyi" selected parameters were: processing time - 15 s, processing frequency 1, angular velocity - 300 s-1, impulses of pressure - 370 kPa. The analysis of experimental data showed the effectiveness of using of alternating impulses of pressure for treatment of liquid nutrient solutions and media for hydroponic system. The productivity of the growing agricultural crop of spring barley "Myronivskyi 22" increased by 32.8% and the productivity agricultural crop of vigorous triticale "Soncedar kharkivskyi" increased by 33.3%. Growth rate for spring barley increase by 20.5%, and for vigorous triticale increased by 22.7%. A study of growing crops using irrigation water showed that as a result of using alternating pressure impulses for processing liquid nutrient solutions and media for a hydroponic system, the yield of the grown agricultural crop of spring barley "Mironovsky 22" increased by 33.3%, and the yield of the agricultural crop of vigorous triticale "Soncedar Kharkivskyi" increased by 33.5%. The growth rate of spring barley increased by 22.2% and of vigorous triticale by 24.4%. The highest yield was obtained using a nutrient solution containing fertilizers. The highest growth rate of experimental crops was observed using irrigation water for drip irrigation systems. Conclusions. Analysis of experimental data showed the effectiveness of using alternating pressure impulses for processing liquid nutrient solutions for hydroponic systems to increase the productivity of cultivated agricultural crops and the yield of green biomass. [ABSTRACT FROM AUTHOR]

Precise control of multiple structural parameters associated with vinyl polymers is important for producing materials with the desired properties and functions. While the development of living polymerization methods has provided a way to control the various structural parameters of vinyl polymers, the concomitant control of their sequence and regioregularity remains a challenging task. To overcome this challenge, herein, we report the living cationic ring‐opening polymerization of hetero Diels–Alder adducts. The scalable and modular synthesis of the cyclic monomers was achieved by a one‐step protocol using readily available vinyl precursors. Subsequently, living polymerization of the cyclic monomers was examined, allowing the synthesis of vinyl polymers while controlling multiple factors, including molecular weight, dispersity, alternating sequence, head‐to‐head regioregularity, and end‐group functionality. The living characteristics of the developed method were further demonstrated by block copolymerization. The synthesized vinyl polymers exhibited unique thermal properties and underwent fast photodegradation even under sunlight. [ABSTRACT FROM AUTHOR]

What is known and objective: The United States is the only country with legislation to approve two classes of biosimilars. One has "no clinically meaningful difference" from the reference product, and when it is tested for switching and alternating, it can receive an interchangeable status. The objective of this review is to establish whether it is possible from the switching and alternating studies to evaluate additional safety or efficacy. Methods: Analysed published data to ascertain if the testing with switching and alternating provide additional proof of safety or efficacy. Political and scientific rationale of creating a new class of biosimilars and how this affects the confidence in biosimilars. Results and discussion: There is no safety or efficacy concern when switching or alternating biosimilars with the reference product. Unfortunately, the rationale for interchangeability is more political than scientific, and it has brought more confusion and mistrust in using biosimilars in the United States. What is new and conclusion: The US Congress is requested to remove the interchangeability clause from the Biological Price and Competition Act to enable faster acceptance of biosimilars and remove the threat of lack of confidence in the safety of biosimilars. [ABSTRACT FROM AUTHOR]

Menasco proved that if G is a reduced, alternating, connected diagram of a link L and G is prime then L is prime. This surprising and important result has been generalized to other classes of links, as well as to tangles and spatial graphs. After exploring some issues with previous results, we obtain new splitting results for tangles and spatial graphs. [ABSTRACT FROM AUTHOR]

Using a simple technique, from the classical Euler–Maclaurin formula is derived the equality ∑ k = 1 n (- 1) k + 1 f (k) = ∑ k = 1 2 m - 1 (- 1) k + 1 f (k) + 1 2 [ f 2 ⌊ n + 1 2 ⌋ - f (2 m) ] - ∑ i = 1 ⌊ p / 2 ⌋ 4 i - 1 B 2 i (2 i) ! [ f (2 i - 1) 2 ⌊ n + 1 2 ⌋ - f (2 i - 1) (2 m) ] + r p (m , n) , true for integers m , n , p ≥ 1 , such that n ≥ 2 m + 1 , and for a function f ∈ C p [ 2 m , n + 1 ] , where the remainder r p (m , n) is estimated as r p (m , n) ≤ 1 + 2 - p 3 π p - 2 ∫ 2 m 2 n + 1 2 f (p) (x) d x. This formula implies also an infinite alternating summation rule having an integral in the error term only. [ABSTRACT FROM AUTHOR]

We continue developing the theory of nilpotent symplectic alternating algebras. The algebras of upper bound nilpotent class, that we call maximal algebras, have been introduced and well studied. In this paper, we continue with the external case problem of algebras of minimal nilpotent class. We show the existence of a subclass of algebras over a field F that is of certain lower bound class that depends on the dimension only. This suggests a minimal bound for the class of nilpotent algebras of dimension 2 n ≥ 8 of rank 2 over any field. [ABSTRACT FROM AUTHOR]

Introduction. The aim of this research was to study the influence of the application of alternating impulses of pressure all through processing in foodstuff production. It was done by the quantitative sensory analysis and tasting evaluation of samples of the wine, fortified wine and associated liquid aqueous systems and solutions. Materials and methods. Wine, fortified wine and associated liquid aqueous systems and solutions were used for investigations and analysing the change of their physical and chemical parameters and properties during the processing by the different methods, approaches, and technological modes. Electrochemical methods were used for the results analysing. A quantitative sensory analysis and tasting evaluation of the experimental liquid samples of wine, fortified wine and associated liquid aqueous systems and solutions was also conducted. Results and discussion. In general, an effect of the treatment in the conditions of alternating impulses of pressure during uninterrupted mode gave the opportunity to increase the general score of a quantitative sensory analysis of wine and fortified wine by 7.3%. During treatment in uninterrupted mode of alternating impulses of pressure with flow shear speed 3.0x105 s-1 and flow shear stress 300 Pa, the general score reached its lowest value 8.4. The verification of the cavitation number from 0.1 to 0.5 gave the possibility to receive the highest general score 8.8 from 10. It substantiates the technology of obtaining the fortified wine involving grape comminution, crest separation, must infusion on the seeds and skins, pressing, must fermentation, blending, and alcoholization. Wine alcoholization is performed under conditions of hydrodynamic cavitation with cavitation number of 0.3, flow shear rate of 2.6·105 s-1 and flow shear stress of 260 Pa. Conclusions. The total score of wine and fortified wine samples obtained under the conditions of alternating impulses of pressure had increased quality indicators compared to control samples, which were obtained by the traditional technology. This has a positive effect on the quality of the finished product. [ABSTRACT FROM AUTHOR]

New semi‐aromatic bio‐based copolyamides PA 4T/4Y and PA 6T/6Y were successfully synthesized in bulk by direct solid‐state polycondensation in which hydrophobic bio‐based dicarboxylic acids sebacic acid, octadecanedioic or hydrogenated dimer fatty acid (Y = C10, C18 or C36) alternate with terephthalic acid T. The absence of a polymerization solvent and the possibility of performing the polymerization on the dicarboxylic acid make it an interesting route for future production of alternating copolyamides. A stepwise synthetic approach is taken where first terephthalic acid‐based diamide diamines of the linear C4 or C6 diamines 4T4 or 6T6 are prepared, followed by preparation of solid salts with the above aliphatic dicarboxylic acids and subjecting the salts to a solid‐state post‐condensation. The alternation is achieved by the interlocking of the 4T4 or 6T6 units in the salts with the bio‐based dicarboxylic acids and polymerizing these salts below the melt temperature of the terephthalamide‐based core. During the polycondensation, the transamidation reaction of the terephthalamide moiety is prevented and with that the randomization of the polyamide. Especially the diaminobutane‐based PA 4T/4Y copolyamides show strict alternation, leading to interesting properties like high crystallinity and high melting points of 250 to 318 °C supported by a randomness value of 2, determined using13C NMR spectroscopy. The special alternating feature becomes especially clear when heating the polymer in the melt state, when the transamidation of the terephthalamide moieties is no longer prevented by the interlocking principle, leading to lowering of the randomness value and therewith the melting point and crystallinity. © 2020 Society of Industrial Chemistry [ABSTRACT FROM AUTHOR]

This paper concerns the braid index of an alternating link. It is well known that the braid index of any link equals the minimum number of Seifert circles among all link diagrams representing it. For an alternating link represented by a reduced alternating diagram D , it is known that s (D) , the number of Seifert circles in D , equals the braid index b (D) of D if D contains no lone crossings, where a crossing in D is called a lone crossing if it is the only crossing between two Seifert circles in D. If D contains lone crossings, then one can reduce the number of Seifert circles in D using link-type preserving moves such as the Murasugi–Przytycki operation. Let r (D) ≥ 1 be the maximum number of Seifert circles in D that can be reduced, then we have b (D) ≤ s (D) − r (D). On the other hand, if the a -span of the HOMFLY polynomial of D satisfies the equality a -span / 2 + 1 = s (D) − r (D) , then the Morton–Frank–Williams (MFW) inequality a -span / 2 + 1 ≤ b (D) leads us to the simple braid index formula b (D) = s (D) − r (D). In this paper, we derive explicit formulas for many alternating links based on minimum projections of these links by establishing the equality a -span / 2 + 1 = s (D) − r (D). Our methods depend on the structures of the link diagrams under consideration and our results lead to explicit braid index formulas that are applicable to a very large class of links, a proper subset of which contains all two bridge links, all alternating pretzel links, and more generally all alternating Montesinos links. The derived braid index formula for an alternating Montesinos link is a function whose inputs are the signs of the crossings in the rational tangles of the Montesinos link. Finally, by applying the now proven Jones Conjecture on the writhe of minimum braids of a link, our results also allow us to obtain explicit formulas of the writhe of minimum braids for the links discussed in this paper from the minimum projections of these links. [ABSTRACT FROM AUTHOR]

Purpose: To compare the outcome of shock wave lithotripsy (SWL) for upper lumbar ureteric stones using the alternating bidirectional approach versus the standard approach during the first session. Methods: Our study was a randomized controlled trial including patients with single radio-opaque stone < 1 cm located in the upper lumbar ureter (from the ureteropelvic junction till the level medial to the lower margin of the kidney). SWL was conducted using electromagnetic Dornier Gemini Lithotripter. In group 1, patients were treated with the alternating under and over-table approach during the first session only and if other sessions were needed, the standard under-table approach was used. In group 2, patients were treated with the standard under-table approach during all sessions. Stone disintegration after the first session was assessed by kidney–ureter–bladder X-ray, renal ultrasonography and noncontrast computed tomography. Moreover, the incidence and severity of postoperative complications were evaluated. Results: Forty-eight patients in each group completed the study. Patient demographics and stone characteristics were comparable in both groups. Complete disintegration was achieved in 41.7% of patients in group 1 versus 18.8% in group 2 (P = 0.021). Stone-free rate (SFR) was 58.3% and 20.8% in group 1 and 2 respectively (P = 0.001). The mean session time was 56.42 min in group 1 versus 46.35 min in group 2 (P < 0.001). There was no significant difference in postoperative complications. Conclusion: Stone disintegration and SFR after the first SWL session are higher when using the alternating bidirectional approach for upper lumbar ureteric stones at the expense of longer procedural duration. Trial registration: ClinicalTrials identifier (ID: NCT03243682), clinicaltrials.gov [ABSTRACT FROM AUTHOR]

We test acculturative stress, Hybrid (HIS) and Alternating (AIS) Identity Styles, and their interaction effects as predictors of psychosocial functioning over a 12-day period among Hispanic American university students. Participants completed measures of acculturative stress, HIS, AIS, and internalizing (anxiety and depression) and externalizing (social aggression and rule-breaking) symptoms on Day 1; on Day 12 they completed the symptom measures a second time. Structural equation modelling was used to examine the Day 1 effects of acculturative stress, cultural identity styles, and their interactions on Day 12 symptoms controlling for the Day 1 symptoms. We hypothesized that acculturative stress would predict more, and the HIS would predict fewer, symptoms and that the AIS would moderate the relationship between acculturative stress and symptoms over time. Results indicated that: (1) acculturative stress predicted an increase in internalizing symptoms; (2) the HIS predicted a decrease in internalizing and externalizing symptoms; and (3) the AIS attenuated the relationship between acculturative stress and externalizing symptoms. The results are discussed in relation to the distinctive features of internalizing and externalizing symptoms, and recommendations for future research are advanced. [ABSTRACT FROM AUTHOR]

A rational link may be represented by any of the (infinitely) many link diagrams corresponding to various continued fraction expansions of the same rational number. The continued fraction expansion of the rational number in which all signs are the same is called a nonalternating form, and the diagram corresponding to it is a reduced alternating link diagram, which is minimum in terms of the number of crossings in the diagram. Famous formulas exist in the literature for the braid index of a rational link by Murasugi and for its HOMFLY polynomial by Lickorish and Millett, but these rely on a special continued fraction expansion of the rational number in which all partial denominators are even (called the all-even form). In this paper we present an algorithmic way to transform a continued fraction given in nonalternating form into the all-even form. Using this method we derive formulas for the braid index and the HOMFLY polynomial of a rational link in terms of its reduced alternating form, or, equivalently, the nonalternating form of the corresponding rational number. [ABSTRACT FROM AUTHOR]

Ito–Takimura recently defined a splice-unknotting number u − (D) for knot diagrams. They proved that this number provides an upper bound for the crosscap number of any prime knot, asking whether equality holds in the alternating case. We answer their question in the affirmative. (Ito has independently proven the same result.) As an application, we compute the crosscap numbers of all prime alternating knots through at least 13 crossings, using Gauss codes. [ABSTRACT FROM AUTHOR]

The 2-periodic function, W ∗ ∈ C 2 (R) is constructed in such a way that the sum ∑ k = 1 n (- 1) k + 1 f (k) can be efficiently estimated for any n ∈ N ∪ { ∞ } and for every f ∈ C 4 [ 1 , ∞) having ∫ 1 ∞ | f (4) (x) | d x < ∞ . [ABSTRACT FROM AUTHOR]

The current study examined the effect of interocular delay in a manual aiming task that required accurate end-point placement, but not precise control of a grip aperture. Participants aimed in binocular, monocular, or alternating monocular vision conditions. For the latter, 25ms monocular samples were provided to alternate eyes without delay (0ms), or a delay of 25 or 50ms. The interocular delay resulted in a longer movement time, caused by a longer time-to-peak and time-after-peak velocity, and a reduction in peak velocity. We suggest that the change in kinematics reflect a strategic response to preserve terminal aiming accuracy and variability when faced with an informational perturbation. These findings indicate that the response to the interocular delay between alternating monocular samples depends on the task-specific information used to control that behavior. [ABSTRACT FROM AUTHOR]

Let $n,r,k\in \mathbb{N}$. An $r$ -colouring of the vertices of a regular $n$ -gon is any mapping $\unicode[STIX]{x1D712}:\mathbb{Z}_{n}\rightarrow \{1,2,\ldots ,r\}$. Two colourings are equivalent if one of them can be obtained from another by a rotation of the polygon. An $r$ -ary necklace of length $n$ is an equivalence class of $r$ -colourings of $\mathbb{Z}_{n}$. We say that a colouring is $k$ -alternating if all $k$ consecutive vertices have pairwise distinct colours. We compute the smallest number $r$ for which there exists a $k$ -alternating $r$ -colouring of $\mathbb{Z}_{n}$ and we count, for any $r$ , 2-alternating $r$ -colourings of $\mathbb{Z}_{n}$ and 2-alternating $r$ -ary necklaces of length $n$. [ABSTRACT FROM AUTHOR]

Poor attention skills constitute a major problem for psychiatric patients with psychotic symptoms, and increase their chances of treatment drop-out. This study investigated possible benefits of musical attention control training (MACT). To examine the effect of MACT on attention skills of psychiatric patients with psychotic features a randomized controlled trial (RCT) was conducted in a forensic psychiatric clinic. Participants (N = 35, age M = 34.7, 69% male) were pair matched (on age, gender, and educational level), and randomly assigned to an experimental and control group. The experimental group received a 30-min MACT training once a week over 6 weeks' time, whereas the controls received treatment as usual without attention training. Single blind pre- and post-neuropsychological assessments were performed to measure different attention levels. The experimental MACT group outperformed the control group in selective, sustained and alternating attention. In addition, overall attendance of MACT participants was high (87.1%). This result suggests that in this experimental pilot study MACT was effective for attention skills of psychiatric patients with psychotic features. To obtain larger intervention effects additional research is necessary, with a larger sample and a more specific MACT intervention. [ABSTRACT FROM AUTHOR]

Novel alternating poly(aryl ether ketone)s (PAEKs) were prepared from a multiple aromatic difluoroketone monomer, that is, containing six aromatic rings via nucleophilic substitution polycondensation with various bisphenols. Each chain segment of the synthesized poly aryl ether ketone alternating copolymer was regularly separated by bisphenol units, which resulted in improvements in their thermal stability and solubility in common organic solvents. All glass transition temperatures of the alternating PAEKs were above 179°C, and the temperatures at 5% weight loss were above 446°C under nitrogen atmosphere. Wide-angle X-ray diffraction patterns confirmed that the resulting PAEKs were amorphous. PAEKs can form strong, transparent, and flexible films by solution casting, with a tensile strength of 72–79 MPa, Young's modulus of 1.5–2.0 GPa, and elongation at break of 7–17%. [ABSTRACT FROM AUTHOR]

Introduction. The purpose of this scientific work is to research the influence of the application of alternating impulses of pressure throughout treatment of liquid solutions by the numerical modelling. Materials and methods. The volume parametric imitation and visualization, modelling methods, math modelling methods were used for the description of the conditions at the working parts of the rotary pulsed apparatus during the liquid treatment. Experimental investigations of liquid samples were carried out with using potentiometry laboratory measurement procedure. Results and discussion. In this paper, it is established that the local values of pressure in the sector of input of water and water systems and the output of the water systems from the gaps vary: at the external surface of the internal rotor from -50 to +300 kPa; at the external stator surface from -150 to 100 kPa; at the inner stator surface from +40 to -120 kPa; at the inner surface of the external rotor from +100 to -100 kPa. During the last values cavitation and adiabatic boiling can be present. Throughout the water and water solutions treatment and during the processes of mixing liquid associated components in the conditions of hydrodynamic fluctuation as alternating impulses of pressure characterized the changing of pressure: ΔР = 350 kPa near an outside surface of an interior spinning rotor; ΔР = 250 kPa near an outside stator surface; ΔР = 160 kPa near an interior stator surface; ΔР = 200 kPa near an interior surface of an outside spinning rotor. By the consequences of the computation was established that the principal values of speeds of shift of a stream emerge in RPA with coaxial clearances between first rotors, stator and second rotor 100 mkm. Conclusions. Throughout the calculations was found the values of pressure changing in working chamber of rotary-pulsating apparatus between coaxial cylinders «rotor-stator-rotor» system. These give us the possibility to receive the liquids with necessary and required physical and chemical properties and parameters by the no reagent influence and to control this processes. [ABSTRACT FROM AUTHOR]

Transcranial alternating-current stimulation (tACS) for entraining alpha activity holds potential for influencing mental function, both in laboratory and clinical settings. While initial results of alpha entrainment are promising, questions remain regarding its translational potential—namely if tACS alpha entrainment is sufficiently robust to context and to what extent it can be upscaled to multi-electrode arrangements needed to direct currents into precise brain loci. We set out to explore these questions by administering alternating current through a multi-electrode montage (mtACS), while varying background task. A multi-electrode analog of previously employed anterior/posterior stimulation failed to replicate the reported alpha entrainment, suggesting that further work is required to understand the scope of applicability of tACS alpha entrainment.

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For ∈ 2 N and p ∈ R the nth partial sum of the alternating p-series, known also as alternating generalized harmonic number of order p... [ABSTRACT FROM AUTHOR]

The article introduces the concept of cultural identity styles, strategies that individuals use for decision making about identity-relevant issues, and proposes that blending and alternating are two strategies that acculturating individuals activate to manage multiple cultural identities. Drawing on diverse samples from New Zealand, Mauritius, and Israel, we present two studies. The first describes the construction of the Multicultural Identity Styles Scale (MISS) and the validation of its Hybrid Identity Style (HIS) and Alternating Identity Style (AIS) subscales. HIS was associated with greater blendedness as assessed by the Bicultural Identity Integration Scale (BIIS-1) and was more prominent in second-generation immigrants compared with their first-generation peers. AIS was associated with less BIIS harmony and was stronger in first-generation immigrants. In the second study, we propose, test, and replicate a mediational model, whereby cultural identity outcomes mediate the impact of cultural identity styles on well-being. Path analysis demonstrated that the motivation to integrate predicted the use of both HIS and AIS; however, HIS led to greater cultural identity consolidation and on to higher levels of well-being. In contrast, AIS predicted greater cultural identity conflict and poorer psychological adaptation. The studies advance our theorizing on biculturalism and integration by adopting a process-oriented approach to cultural identity negotiation. [ABSTRACT FROM AUTHOR]

Transcranial alternating-current stimulation (tACS) for entraining alpha activity holds potential for influencing mental function, both in laboratory and clinical settings. While initial results of alpha entrainment are promising, questions remain regarding its translational potential—namely if tACS alpha entrainment is sufficiently robust to context and to what extent it can be upscaled to multi-electrode arrangements needed to direct currents into precise brain loci. We set out to explore these questions by administering alternating current through a multi-electrode montage (mtACS), while varying background task. A multi-electrode analog of previously employed anterior/posterior stimulation failed to replicate the reported alpha entrainment, suggesting that further work is required to understand the scope of applicability of tACS alpha entrainment. [ABSTRACT FROM AUTHOR]

A novel alternating TiO 2 structure was used as an active layer for dye-sensitized solar cells. The TiO 2 film was prepared with pure TiO 2 nanoparticle paste and mixed polystyrene–TiO 2 paste to form an alternating configuration of dense TiO 2 and micro-/nano-composite porous TiO 2 . The solar cell efficiency was enhanced from 4.91% to 5.58%. A dense TiO 2 layer forms a closer contact with the conducting substrate, and the micro-/nano-composite porous TiO 2 layer favorites dye absorption. Thus, their combination offered better performance. This improvement was attributed to the enhancement of light harvesting, more efficient dye absorption, lower resistance, and longer electron lifetime. [ABSTRACT FROM AUTHOR]

We prove that every homogeneously adequate Kauffman state has enhancements X± in distinct j-gradings whose traces (which we define) represent nonzero Khovanov homology classes over Z/2Z; this is also true over Z when all A-blocks' state surfaces are two-sided. A direct proof constructs X± explicitly. An alternate proof, reecting the theorem's geometric motivation, applies a plumbing (Murasugi sum) operation that has been adapted to the context of Khovanov homology. [ABSTRACT FROM AUTHOR]

An asymptotic approximation of Wallis' sequence m ↦ W m : = ∏ k = 1 m 4 k 2 4 k 2 − 1 is presented as W m = m π 2 m + 1 exp ⁡ ( 2 σ q ( m ) ) ⋅ exp ⁡ ( r q ( m ) ) , where σ q ( x ) : = ∑ i = 1 ⌊ q / 2 ⌋ ( 1 − 4 − i ) B 2 i i ( 2 i − 1 ) ⋅ x 2 i − 1 ( B k are the Bernoulli coefficients ) , and where | r q ( m ) | < r q ⁎ ( m ) : = 2 π ( q − 2 ) ! 3 ( 2 m π ) q − 1 , for any integers m ≥ 1 and q ≥ 2 . Parameters m and q control the error factor exp ⁡ ( r q ( m ) ) . [ABSTRACT FROM AUTHOR]

The present system of vocational training in Morocco is an assembly of models and categories of policy making largely inspired from different countries of the OECD. If the choice of the scholar vocational training has its origin in the common history of both countries, the introduction of other models (dual and vocational training inspired from Germany and Belgium) constructs a composite configuration that results from a socio-political process. These two models are based on an other conception of the regulation of the vocational training-employment relationship, in term of “ occupational market “ that implies that the Moroccan enterprises should participate actively in the production of skills and qualifications. This institutional setting is structured by the rules of the school-enterprise alternating, what distinguishes this formula of the model of the traditional apprenticeship. The application of the Canadian Competency-Based-Education is linked to an other design of the coordination between training centers and workshops.In Morocco the handcraft is anchored in a multi-centuries tradition; so it is a relevant way for analyzing this complex configuration. This choice is justified by the fact it allows to confront the “ modern “ devices of vocational training to the traditional on the job training. So it is possible to reveal the result of co-existence between foreign models and traditional ways to produce the skills.

For a primitive group G acting on a finite set $$\Omega $$ , we define the orbital diameter to be the maximum of the diameters of all orbital graphs of G. In this paper, we study the orbital diameters of symmetric and alternating groups. We give necessary numerical conditions for the orbital diameter to be bounded by some constant c and give precise descriptions of the actions for which the orbital diameter is bounded by 5. For each primitive action, we also either determine all orbital graphs of diameter 2 or give descriptions of infinite families of orbital graphs of diameter 2. [ABSTRACT FROM AUTHOR]

Two main knapping strategies can be used to start bifacial reduction on a lithic cobble or nodule: the alternate strategy, in which first one face is knapped and then the other; and the alternating strategy, in which both faces are removed in the same sequence, interspersing core about-turns between strikes. Flaking reduction of spherical and elliptical blanks (cobbles or nodules) is a common knapping process documented in many archaeological records. Rounded and thick edges require different fracture parameters and give rise to constraints in terms of viable knapping methods. When analysing abandoned cores, it is only possible to see the last strikes, so it is important to know how they were shaped or exploited in the earlier knapping stages in order to understand the entire reduction process. As cortical flakes are the direct evidence of the first reduction phases, we undertook an experimental programme for the purpose of comparing the first flakes generated using the alternate and alternating knapping strategies. We have focused our efforts on identifying and diagnosing distinctive features produced by each strategy in the first or cortical flakes. Our study indicates that several platform attributes can be considered as diagnostic features to differentiate between the alternate and alternating knapping strategies, and that this kind of analysis can be translated to archaeological assemblages. [ABSTRACT FROM AUTHOR]

In this paper and its sequel we continue our study of nilpotent symplectic alternating algebras. In particular we give a full classification of such algebras of dimension 10 over any field. It is known that symplectic alternating algebras over GF(3) correspond to a special rich class of 2-Engel 3-groups of exponent 27 and under this correspondence we will see that the nilpotent algebras correspond to a subclass of that are those groups in that have an extra group theoretical property that we refer to as being powerfully nilpotent and can be described also in the context of -groups where is an arbitrary prime. [ABSTRACT FROM AUTHOR]

Highlights • Allergic fungal rhinosinusitis nature in children is more aggressive when compared to adults. • Endoscopic sinus surgery is an important therapeutic step in the treatment of allergic fungal rhinosinusits. • The reason for this contralateral development of AFRS not clear, but it may be part of the natural disease process. • Involvement of the contralateral sinuses in children is uncommon. The normal uninvolved sinus should be involved in the routine endoscopic examination and the post-operative treatment in order to minimize the risk of disease recurrence. Abstract Objectives to report the alternating nature of allergic fungal rhinosinusitis in children in the Eastern part of Saudi Arabia and to review the experience of King Fahad Specialist Hospital in the diagnosis and management of alternating allergic fungal rhinosinusitis in children. An 8 years old Saudi girl with alternating allergic fungal rhinosinusitis was diagnosed and managed. The patient was diagnosed to have unilateral left allergic fungal rhinosinusitis and underwent endoscopic sinus surgery and cleaning of the left sinuses from polyps, mud and mucin. One year postoperatively the patient developed AFRS in the contralateral right side. Conclusion involvement of the contralateral sinuses in children with AFRS is uncommon. The normal uninvolved sinus should be involved in the routine endoscopic examination and the post-operative treatment in order to minimize the risk of disease recurrence. [ABSTRACT FROM AUTHOR]

The alternating shielding gas technique is a method of achieving transient arc characteristics during arc welding; however the complex flow that occurs through its use has not been investigated previously. A schlieren system was used to image density gradients that arise when alternating argon and helium shield gases, under varying flow parameters, with gas tungsten arc welding (GTAW). A theoretical analysis was carried out to determine the conditions under which the technique facilitates arc pulsing, in particular to avoid mixing of the shield gases in the delivery pipe prior to the welding nozzle. At appropriate pulsing frequency and flow rates, a stable horizontal region of helium was observed in the weld region, maintained in position by the denser argon from the preceding pulse. This higher than average mass fraction of helium when applying the shielding gases alternately, compared to a premixed gas with the same volume of argon and helium, increased the weld penetration by 13% on average, suggesting a modest improvement in heat transfer. [ABSTRACT FROM AUTHOR]

Herein we report the first synthesis of 1,5- di-(ethylphenyl)-1,5-dimethyl-3,3,7,7-tetraphenylcyclotetrasiloxane using a new 'One Pot' procedure as recently reported for the preparation of strictly alternating 1,1,5,5-tetramethyl-3,3,7,7-tetraphenylcyclotetrasiloxane by the heterofunctional condensation of diphenylsilanediol with (phenylethyl)methyldichlorosilane in the presence of the ter tiary amine, triethylamine (Nguyen et al. Silicon 6:21-26 ). The prepared 1,5-di-(ethylphenyl)-1,5-dimethyl-3,3,7,7-tetraphenylcyclotetrasi loxane was fully characterized by single-crystal X-ray diffraction, H, C and Si nuclear magnetic resonance spectroscopy, elemental analysis, mass spectroscopy, thermogravimetric analysis and differential scanning calori metric studies. [ABSTRACT FROM AUTHOR]

Chronic diseases and illnesses associated with unspecific symptoms are on the rise. In addition to chronic stress in social and work environments, physical and chemical exposures at home, at work, and during leisure activities are causal or contributing environmental stressors that deserve attention by the general practitioner as well as by all other members of the health care community. It seems certainly necessary now to take "new exposures" like electromagnetic field (EMF) into account. Physicians are increasingly confronted with health problems from unidentified causes. Studies, empirical observations, and patient reports clearly indicate interactions between EMF exposure and health problems. Individual susceptibility and environmental factors are frequently neglected. New wireless technologies and applications have been introduced without any certainty about their health effects, raising new challenges for medicine and society. For instance, the issue of so-called non-thermal effects and potential long-term effects of low-dose exposure were scarcely investigated prior to the introduction of these technologies. Common EMF sources include Wi-Fi access points, routers and clients, cordless and mobile phones including their base stations, Bluetooth devices, ELF magnetic fields from net currents, ELF electric fields from electric lamps and wiring close to the bed and office desk. On the one hand, there is strong evidence that long-term-exposure to certain EMF exposures is a risk factor for diseases such as certain cancers, Alzheimer's disease and male infertility. On the other hand, the emerging electromagnetic hypersensitivity (EHS) is more and more recognized by health authorities, disability administrators and case workers, politicians, as well as courts of law. We recommend treating EHS clinically as part of the group of chronic multisystem illnesses (CMI) leading to a functional impairment (EHS), but still recognizing that the underlying cause remains the environment. In the beginning, EHS symptoms often occur only occasionally, but over time they may increase in frequency and severity. Common EHS symptoms include headaches, concentration difficulties, sleeping problems, depression, lack of energy, fatigue and flu-like symptoms. A comprehensive medical history, which should include all symptoms and their occurrences in spatial and temporal terms and in the context of EMF exposures, is the key to the diagnosis. The EMF exposure can be assessed by asking for typical sources like Wi-Fi access points, routers and clients, cordless and mobile phones and measurements at home and at work. It is very important to take the individual susceptibility into account. The primary method of treatment should mainly focus on the prevention or reduction of EMF exposure, that is, reducing or eliminating all sources of EMF at home and in the workplace. The reduction of EMF exposure should also be extended to public spaces such as schools, hospitals, public transport, and libraries to enable persons with EHS an unhindered use (accessibility measure). If a detrimental EMF exposure is reduced sufficiently, the body has a chance to recover and EHS symptoms will be reduced or even disappear. Many examples have shown that such measures can prove effective. Also the survival rate of children with leukemia depends on ELF magnetic field exposure at home. To increase the effectiveness of the treatment, the broad range of other environmental factors that contribute to the total body burden should also be addressed. Anything that supports a balanced homeostasis will increase a person's resilience against disease and thus against the adverse effects of EMF exposure. There is increasing evidence that EMF exposure has a major impact on the oxidative and nitrosative regulation capacity in affected individuals. This concept also may explain why the level of susceptibility to EMF can change and why the number of symptoms reported in the context of EMF exposures is so large. Based on our current understanding, a treatment approach that minimizes the adverse effects of peroxynitrite - as has been increasingly used in the treatment of multisystem disorders - works best. This EMF Guideline gives an overview of the current knowledge regarding EMF-related health risks and provides concepts for the diagnosis and treatment and accessibility measures of EHS to improve and restore individual health outcomes as well as for the development of strategies for prevention. [ABSTRACT FROM AUTHOR]

Pressure ulcer prevention is a primary requirement for the NHS. Robust nursing procedures and the provision of pressure-relieving equipment is vital in meeting this requirement. However, the Department of Health also regards making considerable financial savings as a fundamental requirement. There is a firm clinical consensus among national and international bodies that patients at a high risk of developing pressure ulcers, or with existing tissue damage, should be cared for on an alternating (pressure-relieving) mattress system. This evaluation process looks at the performance of the lower cost Air-Flo® 8 Acute alternating (pressure-relieving) mattress system to see if it is effective in meeting the needs of patients. The outcomes suggest that when combined with a pressure ulcer management plan and turning schedule the Air-Flo® 8 Acute performed well, giving an option to continue to care for high-risk patients with an empirically proven effective therapy, while making considerable financial savings. [ABSTRACT FROM AUTHOR]

We consider the real-rootedness of generalized Touchard polynomials recently revisited by Mansour and Schork (2013). Towards this end, we first describe the normal form of the generalized Touchard polynomials, by which recurrence relations for the polynomial part are derived. By using the recurrence relations, we prove the real-rootedness of the generalized Touchard polynomials for the parameter m ∈ [ 1 , ∞ ) ∪ k k + 1 : k ∈ N . [ABSTRACT FROM AUTHOR]

We describe the case of a 92-year-old male patient presenting with shortness of breath and an electrocardiogram showing bradycardia with irregular rhythm and varying QRS morphology. A differential diagnosis is discussed. ( Level of Difficulty: Advanced. )., Competing Interests: Dr Do has received research funding and speaker fees from Medtronic, Inc. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (© 2023 The Authors.)

This article leans on researchs which we led as coordinator and speaker of the course "intervention in Educational Midler" within the framework of a master's degree "Education Teaching, Education Training" set up by the ESPE. The analysis of practices by becoming a dynamic space, allowed to spot and to illustrate the simultaneity of three times occurring in the process of professionalization of the students. The object of this contribution is to operate a putting in the day for the links between this simultaneity of the times and the method and posture adapted by the trainer. The results of this research exposed two axes of questioning in which we wish to continue will be discussed: which epistemology may be used by the trainer to create an open space several timesframes? What is an epistemology of training relationship? [ABSTRACT FROM AUTHOR]

Abstract: Forced convective heat transfer of water based nanofluid (ferrofluid) in the presence of an alternating non-uniform magnetic field is investigated numerically. The geometry is a two-dimensional channel which is subjected to a uniform heat flux at the top and bottom surfaces. Nonuniform magnetic field produced by eight line source dipoles is imposed on several parts of the channel. Also, a rectangular wave function is applied to the dipoles in order to turn them on and off alternatingly. The effects of the alternating magnetic field strength and frequency on the convective heat transfer are investigated for four different Reynolds numbers (Re=100, 600, 1200 and 2000) in the laminar flow regime. Comparing the results with zero magnetic field case, show that the heat transfer enhancement increases with the Reynolds number and reaches a maximum of 13.9% at Re=2000 and f=20Hz. Moreover, at a constant Reynolds number, it increases with the magnetic field intensity while an optimum value exists for the frequency. Also, the optimum frequency increases with the Reynolds number. On the other hand, the heat transfer enhancement due to the magnetic field is always accompanied by a pressure drop penalty. A maximum pressure drop increase of 6% is observed at Re=2000 and f=5Hz which shows that the pressure drop increase is not as significant as the heat transfer enhancement. [Copyright &y& Elsevier]

Objective Alternating hemiplegia of childhood (AHC) is a rare neurodevelopmental syndrome of uncertain etiology. Although the use of magnetic resonance spectroscopy (MRS) for the study of neurologic diseases has grown rapidly over the past decade, its use for AHC patients is quite new. This study was aimed at investigating changes of brain metabolites in patients with alternating hemiplegia of childhood (AHC) during the hemiplegic ictal phases and interictal phases by proton magnetic resonance spectroscopy (1H-MRS). Methods 1H-MRS was used in AHC patients during the hemiplegic ictal phases and interictal phases to evaluate functional activity in certain brain regions. A total of 10 unmedicated, healthy volunteers served as controls. Results N-acetylaspartate (NAA)/Creatine(Cr) ratio of the frontal lobes, basal ganglia, and temporal lobes in contralateral hemiplegic hemisphere of AHC patients during the ictal phases was significantly lower than that in AHC patients during interictal phases and control subjects. Significantly increased choline-containing compounds (Cho)/Cr were obtained in corresponding regions. Conclusions These findings suggest neuronal metabolic dysfunctions in frontal lobes, temporal lobes and basal ganglia in AHC patients during ictal phases that perhaps are involved in the pathogenesis of AHC. [ABSTRACT FROM AUTHOR]