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The 4.2 ka event in the vegetation record of the central Mediterranean

The 4.2 ka event in the vegetation record of the central Mediterranean

compositional variations in vegetation but no clear drop in AP percentages around 4.2 ka, as well as some doubt- ful cases that we will shortly discuss. These sites are represented in yellow in Figs. 1–3. We do not include in this list Lake Preola, where a clear drop in trees peaking around 4.2 ka is compensated for by a shrubland (Calò et al., 2012). By contrast, we include Lago dell’Accesa, where a drop in evergreen oaks around 4.2 ka is com- pensated for by deciduous oaks, which contribute to maintaining forested conditions in spite of a signif- icant compositional change in vegetation (Drescher- Schneider et al., 2007; Vannière et al., 2008). At Lin- gua d’Oca-Interporto, the proximity of the Tiber River and the Tyrrhenian Sea caused repeated floods and the ingress of marine water, which severely affected the record of vegetation dynamics in the hills behind the large coastal wetland, making it difficult to recognize any vegetation change in response to climate events (Di Rita et al., 2015). The Adriatic core RF93-30, which shows a clear drop in AP starting only around 3.9 ka, collects pollen from the Po Valley and north-central Apennines, and only in part from the central and south- ern Italian Peninsula, in spite of its location just north of the Gargano Promontory (Mercuri et al., 2012). At Lago Grande di Monticchio, a slight decrease in AP is recorded ( − 5 %) just before a gap in the pollen record from 4 to 3.5 ka (Allen et al., 2002) that may have con- tributed to masking the 4.2 ka event. At Lago Trifogli- etti, the authors report an intense dry episode around 4.2 ka shown by the reconstructed annual precipitation record, which is not visible in the pollen record (Joannin et al., 2012). One possible explanation for this discrep- ancy is that in this mountain area a high mean annual precipitation (ca. 1850 mm) favors the development of a dense forest, so even a marked decrease in moisture conditions may not provoke any severe decline in forest cover. On the whole, in these “uncertain sites” differ- ent factors may have contributed to partially masking a forest decline.
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Persistence of elevated levels of galactosyl alpha(1 3)galactose antibodies in sera from patients cured of visceral leishmaniasis

Persistence of elevated levels of galactosyl alpha(1 3)galactose antibodies in sera from patients cured of visceral leishmaniasis

This unexpected fact explains why we did not present a longitudinal follow-up study of each of our patients with KA, as studies of our group 5 have demonstrated that 2 to 3 months after [r]

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Was the 4 2 ka Event an Anthropogenic Disaster?

Was the 4 2 ka Event an Anthropogenic Disaster?

occurring ecosystems, might have contributed to the global climate change. Conversion of naturally occurring forests and savannas to fields and pastures could have resulted in a progressive desertification, increasing albedo, changing the direction of airflow from ascending to descending, the disappearance of summer rainfall and the increasing de- pendence of agriculture on the spring snowmelt in mountains. Archaeological research indicates that the first large cities of Mesopotamia were abandoned almost simulta- neously about 4200 years ago, at a time that coincided with a period of extensive deser- tification of areas to the east of the Mediterranean Sea. Features of this desertification were found in studies of stalactites and stalagmites in caves [4] [49] [50] and marine se- diments [5] [51]-[54]. The rapid desertification of the Middle East which took place about 4200 years ago coincided with the rapid global cooling of the climate [6] [7] [55] and was probably related to Bond cycle. However, the cooling related to Bond event 3 proceeded more rapidly than usual. Probably the need to feed a large human popula- tion during the long-term drought and cold forced people to more intense clearing of forests and trees on the savannah, both for fuel and construction, as well as to increase the area suitable for sowing and pastures. Due to drought lasting about 150 years, these forests and trees on the savannah had no possibility of rebirth. Because their cutting down caused an increased albedo and more negative energy balance across several mil- lion square kilometers-from the Atlantic to the Pacific along the Tropic of Can- cer-therefore it could have exacerbated climate cooling not only at these latitudes but also globally. The disappearance of the savannah from the today’s Sahara and the Ara- bian Peninsula as well as cedar-oak-pistacia forests from the Near East, together with the expansion of the Gobi and Ordos Desert in China, increased the albedo of these areas by about 10 percentile points (forest albedo: 5 - 15, farmland albedo: 15 - 25, sa- vannah albedo: 15 - 20, desert albedo: 25 - 30). However, an exact calculation of the impact of changes in earth’s surface albedo on global climate is impossible because the planet’s albedo also depends on the amount and type of clouds and data on this topic are lacking.
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Some thoughts on neural network modelling of micro-abrasion-corrosion processes

Some thoughts on neural network modelling of micro-abrasion-corrosion processes

MLP has been used to model the microabrasion-corrosion process of steel/ polymer couple and a ceramic/lasercarb coating. The basic objective of modelling is to estimate Kac and Kc using the network and compare it with experimental results. Table 5 gives the sample results of estimation for both the data sets. The average total error on training data and test data set is 5.65E-4 and 8.8E-2 for data set 1 and 2.1E-3 and 5.0E-2 for data set 2 respectively. It is clear from the error values and also from the sample results of estimation of Kac and Ka that the network has been able to estimate the values more accurately of the training data than the test data set. The test data contains data not used for training the network.
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(E) 5 [(3 Bromo­phen­yl)diazen­yl] 2 hydr­­oxy 3 meth­oxy­benzaldehyde

(E) 5 [(3 Bromo­phen­yl)diazen­yl] 2 hydr­­oxy 3 meth­oxy­benzaldehyde

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

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5 Cyclo­hexyl 2 methyl 3 (3 methyl­phenyl­sulfin­yl) 1 benzo­furan

5 Cyclo­hexyl 2 methyl 3 (3 methyl­phenyl­sulfin­yl) 1 benzo­furan

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Bran- denburg, 1998); software used to prepare material for publication: SHELXL97.

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5 Cyclo­pentyl 2 methyl 3 (3 methyl­phenyl­sulfon­yl) 1 benzo­furan

5 Cyclo­pentyl 2 methyl 3 (3 methyl­phenyl­sulfon­yl) 1 benzo­furan

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Bran- denburg, 1998); software used to prepare material for publication: SHELXL97.

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(E) 5 [(3 Chloro­phen­yl)diazen­yl] 2 hydr­­oxy 3 meth­oxy­benzaldehyde

(E) 5 [(3 Chloro­phen­yl)diazen­yl] 2 hydr­­oxy 3 meth­oxy­benzaldehyde

packing is further stabilized by – stacking interactions between the C1–C6 and C7–C12 benzene rings of molecules related by an inversion centre [the centroid–centroid distance is 3.8351 (13) A ˚ ], and by a C—H interaction [C14 Cg ii = 3.743 (3) A ˚ , H14B Cg ii = 3.32 A ˚ and C14—H14B Cg ii = 109 ; Cg is the centroid of the C1–C6 ring; symmetry code: (ii) 3

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5 Fluoro 2 methyl 3 (3 methyl­phenyl­sulfon­yl) 1 benzo­furan

5 Fluoro 2 methyl 3 (3 methyl­phenyl­sulfon­yl) 1 benzo­furan

3-Chloroperoxybenzoic acid (77%, 448 mg, 2.0 mmol) was added in small portions to a stirred solution of 5-fluoro-2- methyl-3-(3-methylphenylsulfanyl)-1-benzofuran (245 mg, 0.9 mmol) in dichloromethane (30 mL) at 273 K. After being stirred at room temperature for 8h, the mixture was washed with a saturated sodium bicarbonate solution and the organic layer was separated, dried over magnesium sulfate, filtered and concentrated at reduced pressure. The residue was purified by column chromatography (hexane–ethyl acetate, 4:1 v/v) to afford the title compound as a colorless solid [yield 71%, m.p. 375–376 K; R f = 0.51 (hexane–ethyl acetate, 2:1 v/v)]. Single crystals suitable for X-ray diffraction were
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1 Acetyl 5 (2 meth­oxy­phenyl) 3 (2 meth­oxy­styryl) 2 pyrazoline

1 Acetyl 5 (2 meth­oxy­phenyl) 3 (2 meth­oxy­styryl) 2 pyrazoline

All the rings in (I) are essentially planar and their geometry is independent of the nature of the substituents. The packing in (I) has no correlation with the packing in PYRA1, PYRA2 and PYRA3. The molecules aggregate as double layers parallel to the (101) plane, as shown in Fig. 2. It is interesting to note that consecutive layers, labelled ABAB . . . , are inversely related to one another.

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Dislocation Density Tensor of Thin Elastic Shells at Finite Deformation

Dislocation Density Tensor of Thin Elastic Shells at Finite Deformation

− [v 1 − ξ(v 3 ,1 + v γ B γ 1 )]λ 1 β A β ⊗ A 3 } , (α, β = 1, 2). (23) The equation (23) is obtained for the first time by this paper, which shows that the dislocation density tensor of arbitrary surface of thin shells is proportional to ¯ KA 3/2 . The equation (23) reveals that the displacement component v

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tert Butyl 3 oxo 2 oxa 5 aza­bi­cyclo­[2 2 1]heptane 5 carboxyl­ate

tert Butyl 3 oxo 2 oxa 5 aza­bi­cyclo­[2 2 1]heptane 5 carboxyl­ate

O2 0.0234 (14) 0.0253 (16) 0.0352 (16) 0.0018 (13) 0.0050 (12) −0.0054 (13) O3 0.0253 (15) 0.0189 (14) 0.0349 (16) −0.0018 (13) 0.0067 (12) 0.0007 (13) O4 0.0344 (17) 0.0263 (16) 0.0359 (16) −0.0089 (14) 0.0091 (13) 0.0022 (14) N1 0.0215 (17) 0.0192 (17) 0.0275 (18) 0.0024 (14) 0.0017 (14) −0.0023 (15) C1 0.027 (2) 0.018 (2) 0.031 (2) 0.0018 (17) 0.0092 (17) −0.0050 (17) C2 0.034 (2) 0.018 (2) 0.039 (2) 0.0029 (18) 0.0049 (19) −0.0017 (19) C3 0.037 (2) 0.023 (2) 0.035 (2) −0.0045 (18) 0.0101 (19) −0.0047 (19) C4 0.026 (2) 0.020 (2) 0.034 (2) −0.0009 (17) 0.0064 (17) −0.0039 (18) C5 0.023 (2) 0.0157 (19) 0.029 (2) −0.0012 (16) 0.0028 (16) 0.0015 (16) C6 0.024 (2) 0.021 (2) 0.030 (2) −0.0009 (17) 0.0057 (16) −0.0024 (17) C7 0.028 (2) 0.022 (2) 0.030 (2) −0.0006 (18) 0.0099 (19) −0.0045 (18) C8 0.031 (2) 0.019 (2) 0.028 (2) −0.0005 (17) 0.0056 (17) −0.0007 (18) C9 0.0238 (19) 0.0187 (19) 0.027 (2) −0.0022 (17) 0.0049 (17) −0.0039 (16) C10 0.031 (2) 0.020 (2) 0.025 (2) −0.0038 (18) 0.0024 (17) −0.0047 (17)
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5 Cyclo­hexyl 3 (3 fluoro­phenyl­sulfon­yl) 2 methyl 1 benzo­furan

5 Cyclo­hexyl 3 (3 fluoro­phenyl­sulfon­yl) 2 methyl 1 benzo­furan

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL97.

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5 Chloro 3 ethyl­sulfinyl 2 (3 fluoro­phen­yl) 1 benzo­furan

5 Chloro 3 ethyl­sulfinyl 2 (3 fluoro­phen­yl) 1 benzo­furan

methyl H atoms. The positions of methyl hydrogens were optimized rotationally. The F1 and F2 atoms of the 3-fluoro- phenyl rings are disordered over two positions with site occupancy factors, from refinement of 0.921 (2) (part A) and 0.079 (2) (part B). For the proper treatment of H-atoms, carbon atoms C11 and C13 (molecule A), and C27 and C29 (molecule B) were divided in two parts with equalized coordinates and thermal parameters. The distance of equivalent C– F pairs were restrained to 1.330 (5) Å using command DFIX, and displacement ellipsoids of F1 and F2 sets were
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3 Ethyl­sulfinyl 2 (3 fluoro­phen­yl) 5 phenyl 1 benzo­furan

3 Ethyl­sulfinyl 2 (3 fluoro­phen­yl) 5 phenyl 1 benzo­furan

crystal, molecules are linked by two weak C—H O(sulfinyl) hydrogen bonds and a C—H interaction, forming a sheet, which lies in the ab plane. A – interaction between the benzene and furan rings of neighbouring molecules [centroid– centroid distance = 3.976 (2) A ˚ ] links the molecules into inversion dimers and connects adjacent sheets, resulting in a three-dimensional network.

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5 Ethyl 3 (3 fluoro­phenyl­sulfon­yl) 2 methyl 1 benzo­furan

5 Ethyl 3 (3 fluoro­phenyl­sulfon­yl) 2 methyl 1 benzo­furan

For the biological activity of benzofuran compounds, see: Aslam et al. (2009); Galal et al. (2009); Khan et al. (2005). For natural products with benzofuran rings, see: Akgul & Anil (2003); Soekamto et al. (2003). For structural studies of related 5-alkyl-3-(4-fluorophenylsulfonyl)-2-methyl-1-benzofurans, see: Choi et al. (2010a,b,c).

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5 Bromo 2 methyl 3 (3 methyl­phenyl­sulfin­yl) 1 benzo­furan

5 Bromo 2 methyl 3 (3 methyl­phenyl­sulfin­yl) 1 benzo­furan

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Bran- denburg, 1998); software used to prepare material for publication: SHELXL97.

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5 Cyclo­hexyl 2 methyl 3 (3 methyl­phenyl­sulfon­yl) 1 benzo­furan

5 Cyclo­hexyl 2 methyl 3 (3 methyl­phenyl­sulfon­yl) 1 benzo­furan

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Bran- denburg, 1998); software used to prepare material for publication: SHELXL97.

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5 Cyclo­hexyl 3 ethyl­sulfinyl 2 (3 fluoro­phen­yl) 1 benzo­furan

5 Cyclo­hexyl 3 ethyl­sulfinyl 2 (3 fluoro­phen­yl) 1 benzo­furan

a chair conformation. The dihedral angle between the mean plane [r.m.s. deviation = 0.013 (2) A ˚ ] of the benzofuran ring system and the mean plane [r.m.s. deviation = 0.009 (2) A ˚ ] of the 3-fluorophenyl ring is 24.80 (4) . In the crystal, molecules are connected by C—H O hydrogen bonds, forming chains along [101]. These chains are linked via C—H F hydrogen bonds, forming a three-dimensional structure. There are also interplanar interactions present involving the furan ring of the benzofuran ring system and the 3-fluorophenyl ring [centroid– centroid distance = 3.728 (2) A ˚ ].
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Methyl 3 (2 chloro 5 ethyl 3 pyrid­yl) 3 hydr­­oxy 2 methyl­ene­propanoate

Methyl 3 (2 chloro 5 ethyl 3 pyrid­yl) 3 hydr­­oxy 2 methyl­ene­propanoate

Compound (I) was prepared by the coupling of 2-chloro-5-ethyl- pyridine-3-carbaldehyde (5 mmol) and methyl acrylate (5 mmol) in methanol (5 ml), the reaction mixture being stirred at room temperature in the presence of 1,4-diaza-bicyclo[2.2.2]octane (5 mmol) for 15 min. The mixture was washed with water. Compound (I) was extracted with chloroform (yield 96%). Crystals were grown by slow evaporation of a chloroform solution.

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