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The honey bee constitutes an essential element of the environmental balance in the world as a pollinator of very many species. American foulbrood is a serious disease that threatens local bee colonies. It is considered to be the most harmful disease of the honey bee Apis mellifera. Spores represent the infectious stage. The pathology is caused by the bacterium P. larvae. The objective of this work is to study the prevalence of this pathology in some regions of central Algeria, using microbiological and molecular diagnostic methods. The research of a possible influence of this pathology on the hives mortalities is one of the sought objectives of this work. A sampling was carried out on 6 wilayas at the end of 2019, 100 samples were taken from all the regions studied, but the end of 2019 from 24 apiaries including 4 apiaries by region. A microbiological and a molecular diagnostic method by PCR were used to determine the contamination of bees by the bacterium. The analysis of the results obtained shows that the bacterium Paenibacillus larvae are present in the five areas studied. But bee populations are infested at various levels. Many factors favor the spread of the disease, such as poor beekeeping practices, the high density of honey bee colonies, the sale of swarms and transhumance. The highly pathogenic nature of this disease and the inability to detect it early are partly responsible for its wide spread. [ABSTRACT FROM AUTHOR]

A recent isolated population of Apis florea has been reported from Aqaba in Jordan at the Red Sea, consisting of numerous colonies within a still limited range which apparently is expanding. This region is about 1500 km apart from its next occurrences in Sudan where it had been introduced and first detected in 1985 and about 2000 km apart from its next natural occurrences in Iran and Oman. These bees apparently have been imported by human transport, most likely by ship. This new location thus represents a major jump in the progression of the species still to fill a wide area of possible locations offering adequate living conditions. Here we attempt to track the possible origin of this new population by morphometric methods. This analysis indicated closest relation to A. florea from Oman, thus being the most likely source of this population. [ABSTRACT FROM AUTHOR]

Varroasis is a dangerous pathogen of the honey bee caused by the mite Varroa destructor, the aim of this work is to assess the effectiveness of two natural products (oxalic acid and thymol) in the fight against varroasis. The experiment covered 40 colonies in the central region of Algeria. Two doses of oxalic acid were used: 30 and 45 grams per liter of sugar syrup. For thymol (Thymovar), two treatments were carried out: ½ strip with one and two applications for each group of colonies. The 1/2 strip formulation in two applications at an interval of two weeks apart seems the most effective; the 45 gm solution of oxalic acid has a higher efficacy compared to that of 30 gm, that the effectiveness of oxalic acid is directly linked to the presence of brood at the time of the intervention. these two treatments are of control measure to be integrated by beekeepers as part of an alternative control strategy. [ABSTRACT FROM AUTHOR]

A series of novel, efficient, air-stable, and tunable chiral bisdihydrobenzooxaphosphole ligands (BIBOPs) were developed for rhodium-catalyzed hydrogenations of various functionalized olefins such as α-arylenamides, α-(acylamino)acrylic acid derivatives, β-(acylamino)acrylates, and dimethyl itaconate with excellent enantioselectivities (up to 99% ee) and reactivities (up to 2000 TON). [ABSTRACT FROM AUTHOR]

Phosphine boranes have been found to hydrophosphinate internal, unactivated alkynes at room temperature under basic conditions without the need for catalysts or radical initiators. The use of air-sensitive secondary phosphines is avoided in this facile process. Broad scope in both the phosphine borane and alkyne partners leads to excellent diversity in the phosphine products. Asymmetric hydrogenation of these species then provides one of the shortest possible routes to chiral monodentate phosphines. Hydrophosphination of allenyl phosphine oxides under similar conditions followed by hydrogenation of the exomethylene moiety yields a wide variety of bis-phosphine derivatives. [ABSTRACT FROM AUTHOR]

Reaction of 4-bromo-NH-1,2,3-triazoles 2with alkyl halides in the presence of K2CO3in DMF produced the corresponding 2-substituted 4-bromo-1,2,3-triazoles 5in a regioselective process. Subsequent Suzuki cross-coupling reaction of these bromides provided an efficient synthesis of 2,4,5-trisubstituted triazoles 3. In addition, reduction of the bromotriazoles by hydrogenation furnished an efficient synthesis of 2,4-disubstituted triazoles 8. [ABSTRACT FROM AUTHOR]

Asymmetric hydrogenation of unsaturated urea esters with the BIPI Ligands has been examined. Optimization of the P−N ligand structure has led to the development of chiral rhodium catalysts capable of producing the targets with >99% ee. The critical phosphine borane SNAr reaction needed for ligand synthesis has been optimized to give the adducts in high yield at ambient temperature with no racemization. An extremely concise, economical, and scalable sequence to these important new ligands for catalysis of asymmetric hydrogenation has been developed. [ABSTRACT FROM AUTHOR]

Beeswax is composed of fatty acids, odd numbered n-alkanes and wax esters. Focusing on the most stable components of beeswax, namely the n-alkanes, we have found by gas chromatography and gas chromatography-mass spectrometry analyses of combs from twelve colonies from Israel and Jordan that as beeswax ages and darkens its n-alkane composition changes. The amount of even numbered n-alkanes (C22-C32) is significantly higher in darker colored beeswax as compared to light colored beeswax. We attribute this in part to the accumulation of cuticular residues found in the darker colored comb cells. Cuticular residues are known to contain C23-C32odd and even numbered n-alkanes. [ABSTRACT FROM AUTHOR]

The palladium catalyzed alkoxycarbonylation and aminocarbonylation of vinyl tosylates are described. A variety of ketone and aldehyde derived vinyl tosylates may be carbonylated in the presence of primary, secondary, and tertiary alcohols, or primary and secondary amines, to provide the corresponding esters and amides in good yields. The alkoxycarbonylation was applied to a short synthesis of isoguvacine. [ABSTRACT FROM AUTHOR]

Reaction of 4,5-dibromo-1,2,3-triazole with electron-deficient aromatic halides in the presence of potassium carbonate in DMF produces the corresponding 2-aryl-4,5-dibromotriazoles with high regioselectivity. Subsequent debromination of these triazoles by hydrogenation furnishes 2-aryltriazoles in excellent yields. Overall, this two-step process provides an efficient access to 2-aryl-1,2,3-triazoles. [ABSTRACT FROM AUTHOR]