Evaluating the dendroclimatological potential of Taxus baccata (yew) in southwest Ireland

Tree-ring research in Ireland has typically been dominated by Quercus species, particularly Quercus petraea and Quercus robur. Recent years have seen a greater focus on multi-species reconstructions in Ireland but, due to difficulties with the hardness of the wood, missing/pinched rings and fused stems, Taxus baccata has not been included in these investigations. Despite these difficulties, a 31-tree, 204-year T. baccata chronology was successfully constructed from Killarney National Park, southwest Ireland. The chronology exhibits promising dendroclimatological potential, with climatic responsiveness equivalent to that of the other major Irish tree taxa, including Quercus. The chronology shows the strongest relationship with May–June precipitation from Muckross House synoptic station (1970–2007; r = 0.521, p < 0.01) and Valentia Observatory (1941–2007; r = 0.545, p < 0.01). November–April temperatures also exhibited a strong relationship with the chronology post-1970 (r = 0.605, p < 0.01 for Muckross House, r = 0.567, p < 0.01 for Valentia Observatory), but this relationship is not time stable and breaks down for the pre-1970 Valentia Observatory record. The long-lived nature of T. baccata, the exceptional preservation of wood and rings in this hard softwood species, as well as its prominence in Irish archaeology, all point to the potential to expand this chronology both spatially and temporally, and demonstrate T. baccata's potential in multi-site and multi-species tree-ring studies in the region.     

The historical dendroarchaeology of two log structures at the Wynnewood State Historic Site,Castalian Springs,Tennessee, USA

Tree rings of eastern red cedar (Juniperus virginiana L.) were examined from cores extracted from two log cabins located at the Wynnewood State Historic Site in Castalian Springs, Sumner County, Tennessee. One cabin was reportedly built by the first explorer in the area, Isaac Bledsoe, sometime between 1772 and his death in 1793. The second cabin was known as Spencer's Cabin after the first settler of the region, Thomas Sharp Spencer, who lived in the immediate vicinity from 1776 to 1779. The goal of this research was to determine the probable construction year(s) for both cabins and determine whether Bledsoe and Spencer did indeed build these structures. Forty-one cores were extracted from Bledsoe's Cabin, and 30 were used for crossdating and building a floating chronology using COFECHA. The Bledsoe's Cabin chronology was then statistically and graphically crossdated using the eastern red cedar reference tree-ring chronology (ITRDB #TN031) from Norris Dam, Tennessee. We found a statistically significant correlation (r = 0.42, t = 4.18, n = 85, p < 0.0001) between the Bledsoe's Cabin chronology and the reference chronology, anchoring the chronology between 1720 and 1804, with nearly all cores indicating tree harvesting between February and April 1805. Twenty-two cores were extracted from Spencer's Cabin, and 17 were used to build a floating chronology for the cabin. Again, we found a statistically significant correlation (r = 0.44, t = 4.85, n = 100, p < 0.00001) with the reference chronology, which anchored the Spencer's Cabin chronology between 1726 and 1825. All trees appear to have been harvested between February and August in 1826. Therefore, neither structure was built by its historical namesake. No known historical documents suggest who the potential builders were, although the property was owned between ca. 1797 and 1829 by General James Winchester. He and his family, however, never resided on the Wynnewood property because Winchester had built a large multi-room structure in nearby Gallatin, Tennessee, by 1802.     

An attempt to dendrochronologically date house features at the King site (9FL5), a 16th century Late Mississippian town in northwestern Georgia,USA

The King site is a Late Mississippian (ca. 1400–1540 CE) aboriginal town located in northwestern Georgia along the Coosa River associated with the Coosa Chiefdom. The site was settled ca. 1530 but was occupied for perhaps only 50 years or so based on the lack of horizontal stratigraphy. The site was visited by members of either or both the Hernando de Soto expedition in 1540 and/or the Tristan de Luna expedition in 1560. In 1974, archaeologists discovered and removed 36 sections of subterranean charred pine posts from six house features. Our objectives were to determine if the tree rings on these posts could be dendrochronologically dated to verify the dates of site occupation and confirm the construction sequence of several houses determined originally via stratigraphic and archaeological evidence. We were able to graphically and statistically crossmatch 13 measurement series representing 10 posts from 5 of the 6 structures, yielding a 157-year floating chronology (average interseries correlation = 0.60). We were unable to absolutely crossdate this floating chronology with the only regional reference chronology long enough (back to 1378 CE) to reach the 16th century, an eastern red cedar chronology from eastern Tennessee. Archaeological evidence indicated Houses 8 and 23.4 were built later in the King site occupancy, confirmed by the tree-ring dates as both houses have the youngest tree rings of the five structures. House 14 had the oldest outermost tree rings but archaeological evidence suggests this house also was likely constructed late in the King site occupancy. We propose some posts were salvaged and reused from abandoned houses as the King site became rapidly depopulated in the last 10–20 years of site occupancy, thus explaining the age of posts used in House 14. We urge archaeologists working in the Southeastern U.S. to consider developing a more formal process for exhuming and preserving charcoalized wood remains from archaeological sites so that these samples can be evaluated using dendrochronological techniques.     

Historical dendroarchaeology of two log structures in the Valles Caldera National Preserve,New Mexico,USA

We used dendroarchaeological techniques to determine the year of construction of two historic structures in the Valles Caldera National Preserve of New Mexico, USA. Historical documents date some structures in the headquarters area of the Preserve, but the Commissary Cabin and Salt Barn were lacking conclusive construction dates. Both structures were originally thought to have been built by the Otero family who bought the property in 1899. We found that the structures were built from two tree species, white fir (Abies concolor (Gordon) Lindl. ex Hildebr.) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), surprising given that ponderosa pines are also found in great numbers in the adjacent forest. Tree rings from 20 logs were confidently crossdated both graphically and statistically and provided cutting dates of trees in both structures of 1940 and 1941 when compared against the Fenton Lake reference chronology (Commissary Cabin: r = 0.69, t = 15.54, p < 0.0001, n = 263 years; Salt Barn: r = 0.77, t = 11.7, p < 0.0001, n = 232 years). By combining the cutting date years and terminal ring attributes, we suggest that both structures were built in the spring or early summer of 1941 using freshly cut logs and logs that had been cut the previous spring (1940, before or during the growing season) and stockpiled. The cutting dates of 1940 and 1941 indicate that these buildings were constructed during the Franklin Bond (1939–1945) era and associated with the transition from sheep ranching to more modern cattle grazing. These new dates provide a more distinct understanding of the cultural resources at the Valles Caldera National Preserve and provide interpretative staff with more accurate information that can be given to the public.     

Prevalence and resting behaviour of dengue vectors,Aedes aegypti and Aedes albopictus in dengue high risk urban settings in Colombo,Sri Lanka

Understanding local geographical variation in vector density and bionomics related to virus transmission are critical for planning effective vector control programs to control dengue virus transmission. This study investigated the prevalence and resting behaviour of Aedes aegypti and Ae. albopictus in three dengue high-risk areas in the Colombo District, Sri Lanka. Monthly sampling of resting adult mosquitoes was conducted from August 2019 to February 2020. Thirty-seven percent of the households (289/776) harboured Aedes mosquitoes, and 603 Aedes mosquitoes were collected. The proportion of Ae. aegypti was higher in the overall collection during the collection period (94% [569/603]), and 62% (352/569) were females. Significant monthly variations in Ae. aegypti were observed with respect to the indices: number of females per surveyed house (F/SH; p = 0.001), number of females per Aedes positive house (F/PH; p = 0.029), adult house index (AHI; p = 0.001), adult density (AD; p = 0.005) and resting ratio (RR; p = 0.001). AHI, AD, and RR had statistically significant positive correlations with monthly rainfall (p = 0.001, p = 0.011, and p = 0.002 respectively) and one-month lagged dengue cases (p = 0.002, p = 0.005, and p < 0.001 respectively). A statistically significantly higher proportion of Ae. aegypti females were caught resting indoors (N = 309, 88%) than outdoors (N = 43, 12%; p < 0.001). The most common resting areas were bedrooms (51%) & living/dining rooms (37%), and places were under or on furniture (47%) & hangings (34%) for Ae. aegypti. Conversely, 74% of female Ae. albopictus were collected outdoors. Results of this study could have strong implications to improve vector surveillance and control by early detection of dengue to detect outbreaks and minimization of disease transmission.     

The effect of glucose and maltose concentrations on pyruvate and ascorbate production,antioxidant enzyme activities and LPO levels in Fusarium equiseti

Changes in pyruvate and ascorbate production and antioxidant enzyme activities together with lipid peroxidation levels in Fusarium equiseti were investigated in relation to changes in the concentrations of glucose and maltose as carbon sources in the range of 5–25 g/l in Armstrong Fusarium Medium (AFM). The highest pyruvate concentration obtained at 20 g/l maltose was 67.5 ± 0.69 μg/ml while ascorbic acid reached a maximum value at 25 g/l glucose of 1866±26.1 μg/ml The maximum superoxide dismutas (SOD) activities related to increased pyruvate production were determined in AFM medium containing 20 g/l glucose as 41.49±0.65 and maltose as 61.12±0.8 IU/mg. Catalase (CAT) activity variations showed coherence with SOD activity in a medium containing maltose and reached 219.11±2.8 IU/mg while they were decreased with increasing glucose concentration. glutathione peroxidase (GSH-Px) activities in F. equiseti did not change significantly with glucose and maltose concentration and were determined to be 1.21±0.22 and 1.67±0.15 IU/mg, respectively. Minimum lipid peroxidation levels for each carbon source were determined in both 20 g/l maltose and glucose concentrations as 0.9 and 1.62 nmol MDA/g wet weight.     

A multi-century eastern white pine tree-ring chronology developed from salvaged river logs and its utility for dating heritage structures in Canada's National Capital Region

The early settlement history of Canada's National Capital Region, including Ottawa (Ontario) and Gatineau (Québec), was shaped in large part by the towering eastern white pine (Pinus strobus) forests that once covered the Ottawa Valley and fuelled a lucrative lumber export industry spanning the 19th and much of the 20th century. Some of the first dwellings and farmsteads of this era are still standing and serve as reminders of this history. A crucial piece of information in the assessment of a structure's heritage value is its date of construction. Unfortunately, this information is not always known and is approximated based on construction styles and other sources of information. In this study, dendroarchaeology methods are applied to constrain the construction dates of six historic structures in the National Capital Region of 19th century vintage. A multi-century (AD 1670–2009) eastern white pine ring-width chronology was developed for dating the study structures using cross sections from sunken logs recovered from the Ottawa River and cores from live trees from the Petawawa Research Forest. The tree-ring inferred construction dates for the six structures ranged from 1830 to 1878. For most structures, historical records about the property or first inhabitants were available to corroborate the results. The ring-width chronologies of the individual structures were well correlated with the regional chronology (r_avg = 0.63, p ≤ 0.01), and this regional coherence clearly demonstrates the value of tree-rings for heritage structure assessments and reconstructing the settlement history of this region.     

A 1700-year Athrotaxis selaginoides tree-ring width chronology from southeastern Australia

Few Southern Hemisphere tree-ring chronologies exceed 1000 years in length. We present a ca. 1700 years of indexed values for the long-lived conifer Athrotaxis selaginoides at Cradle Mt in southeastern Australia and compare it with the only other published millennial-plus length tree-ring chronology for Australia: the nearby Mt Read Lagarostrobos franklinii. We use simple correlation function and pointer year analyses to compare the climate responses of the two species (temperature, precipitation and growing degree days). Both chronologies show accelerated growth at their modern ends, but this growth acceleration is not synchronous, beginning approximately a quarter of a century earlier at the Cradle Mt site. This discrepancy may highlight the relevance of chronology composition and/or physiological differences in the species. Although the seasonality of the climatic responses of the two species is similar, that of A. selaginoides is generally weaker than that of L. franklinii. Somewhat paradoxically, the only pointer years in common between the chronologies are 1898 and 1908 CE. The periods from 600 to 900 CE and ∼1200–1450 CE are conspicuous for their absence of positive pointer years while no negative pointer years occur for either site from ∼1200–1350 CE. It is possible that differing patterns of pointer years can be partially explained by a peak in establishment from ∼1150–1850 CE at the Mt Read L. franklinii site compared to continuous establishment at Cradle Mt. Although statistically significant and time-stable climate responses for the A. selaginoides chronology are too weak to base a single-chronology climate reconstruction on, the long chronology will likely make an important contribution to future multi-proxy temperature reconstructions for southeastern Australia.     

June–September temperature reconstruction in the Northern Caucasus based on blue intensity data

Although long-lived trees grow in the Northern Caucasus, no single tree-ring chronology has been reported thus far from this area in the International Tree-Ring Data Base (ITRDB), neither has one been published in international journals. Extensive tree-ring studies were conducted over the last decade, and a tree-ring network was developed for the investigated area. The data on the minimum blue intensity based on 33 series of pine (Pinus sylvestris L.) and fir (Abies nordmanniana (Steven) Spach) is presented in this study. The minimum blue intensity (BI) chronology covers the period 1596–2011 with EPS value ≥0.85. The BI chronology strongly correlates with the mean June-September temperature (R = 0.74; p < 0.05) from the weather station “Kluhorskij Pereval” (1951–2011). Mean June-September temperature anomalies were reconstructed using the rescaling method. Based on the reconstruction provided in this study the twentieth century is characterized by highly increased June-September temperature. According to this study, the minimum blue intensity approach demonstrates a great potential for paleoclimatic research in the Caucasus. Vast spatial coverage of the new BI-based reconstruction based on data from only two locations in the Northern Caucasus provides prospects for reconstruction of temperature variations for a great region in the Middle East and Northern Africa.     

Diabetes,metformin use,and colorectal cancer survival in postmenopausal women

Background: Observational studies have associated metformin use with lower colorectal cancer (CRC) incidence but few studies have examined metformin's influence on CRC survival. We examined the relationships among metformin use, diabetes, and survival in postmenopausal women with CRC in the Women's Health Initiative (WHI) clinical trials and observational study. Methods: 2066 postmenopausal women with CRC were followed for a median of 4.1 years, with 589 deaths after CRC diagnosis from all causes and 414 deaths directly attributed to CRC. CRC-specific survival was compared among women with diabetes with metformin use (n = 84); women with diabetes with no metformin use (n = 128); and women without diabetes (n = 1854). Cox proportional hazard models were used to estimate associations among metformin use, diabetes and survival after CRC. Strategies to adjust for potential confounders included: multivariate adjustment with known predictors of colorectal cancer survival and construction of a propensity score for the likelihood of receiving metformin, with model stratification by propensity score quintile. Results: After adjusting for age and stage, CRC specific survival in women with diabetes with metformin use was not significantly different compared to that in women with diabetes with no metformin use (HR 0.75; 95% CI 0.40–1.38, p = 0.67) and to women without diabetes (HR 1.00; 95% CI 0.61–1.66, p = 0.99). Following propensity score adjustment, the HR for CRC-specific survival in women with diabetes with metformin use compared to non-users was 0.78 (95% CI 0.38–1.55, p = 0.47) and for overall survival was 0.86 (95% CI 0.49–1.52; p = 0.60). Conclusions: In postmenopausal women with CRC and DM, no statistically significant difference was seen in CRC specific survival in those who used metformin compared to non-users. Analyses in larger populations of colorectal cancer patients are warranted.     

Lethal effects of ichthyotoxic raphidophytes,Chattonella marina,C. antiqua,and Heterosigma akashiwo,on post-embryonic stages of the Japanese pearl oyster,Pinctada fucata martensii

The inimical effects of the ichthyotoxic harmful algal bloom (HAB)-forming raphidophytes Heterosigma akashiwo, Chattonella marina, and Chattonella antiqua on the early-life stages of the Japanese pearl oyster Pinctada fucata martensii were studied. Fertilized eggs and developing embryos were not affected following exposure to the harmful raphidophytes; however, all three algal species severely affected trochophores and D-larvae, early-stage D-larvae, and late-stage pre-settling larvae. Exposure to C. marina (5 × 10² cells ml⁻¹), C. antiqua (10³ cells ml⁻¹), and H. akashiwo (5 × 10³ cells ml⁻¹) resulted in decreased success of metamorphosis to the trochophore stage. A complete inhibition of trochophore metamorphosis was observed following exposure to C. antiqua at 5 × 10³ cells ml⁻¹ and C. marina at 8 × 10³ cells ml⁻¹. In all experiments, more than 80% of newly formed trochophores were anomalous, and in the case of exposure to H. akashiwo at 10⁵ cells ml⁻¹ more than 70% of D-larvae were anomalous. The activity rates of D-larvae (1-day-old) were significantly reduced following exposure to C. antiqua (8 × 10³ cells ml⁻¹, 24 h), C. marina (8 × 10³ cells ml⁻¹, 24 h), and H. akashiwo (10⁴ cells ml⁻¹, 24 h). The activity rates of pre-settling larvae (21-day-old) were also significantly reduced following exposure to C. antiqua (10³ cells ml⁻¹, 24 h), C. marina (8 × 10³ cells ml⁻¹, 24 h), and H. akashiwo (5 × 10⁴ cells ml⁻¹, 24 h). Significant mortalities of both larval stages were induced by all three raphidophytes, with higher mortality rates registered for pre-settling larvae than D-larvae, especially following exposure to C. marina (5 × 10²–8 × 10³ cells ml⁻¹, 48–86 h) and C. antiqua (10³–8 × 10³ cells ml⁻¹, 72–86 h). Contact between raphidophyte cells and newly metamorphosed trochophores and D-larvae, 1-day-old D-larvae, and 21-day-old larvae resulted in microscopic changes in the raphidophytes, and then, in the motile early-life stages of pearl oysters. Upon contact and physical disturbance of their cells by larval cilia, H. akashiwo, C. marina and C. antiqua became immotile and shed their glycocalyx. The trochophores and larvae were observed trapped in a conglomerate of glycocalyx and mucus, most probably a mixture of larval mucous and raphidophyte tricosyts and mucocytes. All motile stages of pearl oyster larvae showed a typical escape behavior translating into increased swimming in an effort to release themselves from the sticky mucous traps. The larvae subsequently became exhausted, entrapped in more heavy mucous, lost their larval cilia, sank, become immotile, and died. Although other toxic mediators could have been involved, the results of the present study indicate that all three raphidophytes were harmful only for motile stages of pearl oysters, and that the physical disturbance of their cells upon contact with the ciliary structures of pearl oyster larvae initiated the harmful mechanism. The present study is the first report of lethal effects of harmful Chattonella spp. towards larvae of a bivalve mollusc. Blooms of H. akashiwo, C. antiqua and C. marina occur in all major cultivation areas of P. fucata martensii during the developmental period of their larvae. Therefore, exposure of the motile early-life stages of Japanese pearl oysters could adversely affect their population recruitment. In addition, the present study shows that further research with early-life development of pearl oysters and other bivalves could contribute to improving the understanding of the controversial harmful mechanisms of raphidophytes in marine organisms.     

EPA,DHA, cholesterol and phospholipid content in Pagrus pagrus (cultured and wild), Trachinus draco and Trigla lyra from Mediterranean Sea

EPA, DHA, cholesterol and phospholipid content were determined in the Trachinus draco, Trigla lyra and (wild and cultured) Pagrus pagrus muscles.The EPA and DHA levels – as determined by GC-GC/MS – in the cultured P. pagrus muscles (233.20 ± 16.3 and 399.39 ± 31.1 mg/100 g of the wet tissue respectively) were found to be significantly higher compared to the ones in the wild P. pagrus, T. draco and T. lyra (26.31 ± 2.26, 158.24 ± 10.92 mg/100 g, 28.65 ± 1.68, 155.97 ± 2.63 mg/100 g 35.66 ± 0.66 and 102.52 ± 1.71 mg/100 g of the wet muscles respectively). The amounts of cholesterol (determined by GC on a capillary column) and phospholipids in the cultured P. pagrus muscles were significantly higher (149.3 mg/100 g and 0.80 g/100 g of the wet tissue respectively) compared to the ones in the wild P. pagrus (8.73 mg/100 g and 0.40 g/100 g), T. draco (41.72 mg/100 g and 0.59 g/100 g) and T. lyra muscles (38.63 mg/100 g and 0.40 g/100 g of the wet tissue respectively).The highest DHA/EPA and ω-3/ω-6 ratios were 6.00 and 5.93 in wild P. pagrus and T. draco muscles respectively, while the lowest in cultured P. pagrus (1.71 and 1.48 respectively).     

Influence of different types of environmental enrichment on the behaviour of finishing pigs in two different housing systems: 3. Hanging toy versus rootable toy of the same material

This study aimed to assess the effects of (1) environmental enrichment with either straw bedding or a plastic toy and (2) the way in which the plastic toy was presented on the behaviour of finishing pigs in two different housing systems. One thousand and twenty four (Large White × Landrace) × Large White pigs were housed contemporarily in either a straw-based (ST) or fully slatted (FS) building from 35 kg to slaughter at 104 kg. In each building, half of the pens received additional environmental enrichment in the form of a hanging plastic toy. The remaining pens in the ST house were enriched only by the straw bedding. In the FS house, the remaining pens were provided with a rootable toy of the same plastic material presented on the floor of the pen. There was no significant effect of housing system on the level of manipulation of the hanging toy. Within the FS system, the level of manipulation of the hanging toy tended to be higher than that of the plastic toy presented on the floor (P = 0.052). Neither form of additional environmental enrichment provided a comparable level of occupation to that of straw bedding. In the absence of straw, more investigatory behaviours were directed towards both pen-mates (P < 0.001) and pen components (P < 0.001). Further study is required to identify functional forms of environmental enrichment in slatted systems to occupy pigs and prevent them from performing adverse behaviours.     

Growth,intake, diet digestibility,and nitrogen use in three hair sheep breeds fed alfalfa hay

Pen feeding and metabolism trials were conducted to determine intake, diet digestibility and nitrogen (N) use in three hair sheep breeds with differing growth potential offered an alfalfa hay diet. For pen feeding, 24 6-mo-old wether lambs, equally representing the Barbados Blackbelly, Katahdin, and St. Croix breeds, were paired by breed, placed in 12 enclosed cement-floor pens (2.5 m × 3.5 m), and offered chopped alfalfa (Medicago sativa L.; 17.6% CP, 50.4% NDF, and 36.4% ADF) ad libitum. Lambs were allowed a 14-d adaptation period to pens and diets, and remained on trial for 56 d. Starting body weight (BW) was different (P < 0.05) among breeds (Barbados Blackbelly: 23.8 kg; Katahdin: 36.5 kg; St. Croix: 29.1 kg). Daily gain was not different (P < 0.10) between Katahdin (131 g/d) and St. Croix (117 g/d), but both were higher (P < 0.05) than Barbados Blackbelly (87 g/d). Daily dry matter hay intake was similar among breeds (107–109 g/kg BW^0.75), and feed to gain ratio ranged from 8.7 in St. Croix and 9.1 in Katahdin to 10.5 in Barbados Blackbelly, but was not different (P > 0.10) among breeds. Six lambs per breed were used in the metabolism trial. Total DMI was greater (P < 0.01) for Katahdin (1196 g/d) than St. Croix (907 g/d) and Barbados Blackbelly (858 g/d), but was not different (P > 0.10) adjusted for body weight (mean: 71 g/kg BW^0.75). Coefficients of apparent digestibility for DM (P < 0.06), OM (P < 0.06), N (P < 0.05), NDF (P < 0.08), and ADF (P < 0.08) were higher for Katahdin compared to Barbados Blackbelly with St. Croix intermediate. Intake of N (P < 0.01), feces N (P < 0.08), urine N (P < 0.01), absorbed N (P < 0.01), and retained N (P < 0.05) also were greater for Katahdin compared to St. Croix and Barbados Blackbelly. Blood glucose, urea-N, and creatinine were not different (P > 0.10) among breeds. Breeds differed in their growth performance in line with breed mature size, and differences were observed in N digestibility and absorption.     

Purification,characterization, and crystallization of the adhesive domain of SdrD from Staphylococcus aureus

The adhesive domain of SdrD from Staphylococcus aureus was solubly expressed in Escherichia coli in high yield. After a series of purification steps, the purified protein was >95% pure, which was SdrD from S. aureus identified by SDS–PAGE and MALDI-TOF MS. Crystals were grown at 18 °C using 25% polyethylene glycol 3350 as precipitant. Diffraction by the crystal extends to 1.65 Å resolution, and the crystal belongs to the space group C2, with the unit cell parameters a = 133.3, b = 58.3, c = 112.3 Å, α = 90.00, β = 111.14, γ = 90.00.     

Novel insights into cyclooxygenases,linoleate diol synthases,and lipoxygenases from deuterium kinetic isotope effects and oxidation of substrate analogs

Cyclooxygenases (COX) and 8R-dioxygenase (8R-DOX) activities of linoleate diol synthases (LDS) are homologous heme-dependent enzymes that oxygenate fatty acids by a tyrosyl radical-mediated hydrogen abstraction and antarafacial insertion of O₂. Soybean lipoxygenase-1 (sLOX-1) contains non-heme iron and oxidizes 18:2n ? 6 with a large deuterium kinetic isotope effect (D-KIE). The aim of the present work was to obtain further mechanistic insight into the action of these enzymes by using a series of n ? 6 and n ? 9 fatty acids and by analysis of D-KIE. COX-1 oxidized C₂₀ and C₁₈ fatty acids in the following order of rates: 20:2n ? 6 > 20:1n ? 6 > 20:3n ? 9 > 20:1n ? 9 and 18:3n ? 3 ≥ 18:2n ? 6 > 18:1n ? 6. 18:2n ? 6 and its geometrical isomer (9E,12Z)18:2 were both mainly oxygenated at C-9 by COX-1, but the 9Z,12E isomer was mostly oxygenated at C-13. A cis-configured double bond in the n ? 6 position therefore seems important for substrate positioning. 8R-DOX oxidized (9Z,12E)18:2 at C-8 in analogy with 18:2n ? 6, but the 9E,12Z isomer was mainly subject to hydrogen abstraction at C-11 and oxygen insertion at C-9 by 8R-DOX of 5,8-LDS. sLOX-1 and 13R-MnLOX oxidized [11S-²H]18:2n ? 6 with similar D-KIE (~ 53), which implies that the catalytic metals did not alter the D-KIE. Oxygenation of 18:2n ? 6 by COX-1 and COX-2 took place with a D-KIE of 3–5 as probed by incubations of [11,11-²H₂]- and [11S-²H]18:2n ? 6. In contrast, the more energetically demanding hydrogen abstractions of the allylic carbons of 20:1n ? 6 by COX-1 and 18:1n ? 9 by 8R-DOX were both accompanied by large D-KIE (> 20).     

Stature,body mass,and brain size: A two-million-year odyssey

Physical size has been critical in the evolutionary success of the genus Homo over the past 2.4 million-years. An acceleration in the expansion of savannah grasslands in Africa from 1.6 Ma to 1.2 Ma witnessed concomitant increases in physical stature (150–170 cm), weight (50–70 kg), and brain size (750–900 cm³). With the onset of 100,000 year Middle Pleistocene glacial cycles (“ice ages”) some 780,000 years ago, large-bodied Homo groups had reached modern size and had successfully dispersed from equatorial Africa, Central, and Southeast Asia to high-latitude localities in Atlantic Europe and North East Asia. While there is support for incursions of multiple Homo lineages to West Asia and Continental Europe at this time, data does not favour a persistence of Homo erectus beyond ～400,000 years ago in Africa, west and Central Asia, and Europe. Novel Middle Pleistocene Homo forms (780,000–400,000 years) may not have been substantially taller (150–170 cm) than earlier Homo (1.6 Ma–800,000 years), yet brain size exceeded 1000 cm³ and body mass approached 80 kg in some males. Later Pleistocene Homo (400,000–138,000 years) were ‘massive’ in their height (160–190 cm) and mass (70–90 kg) and consistently exceed recent humans. Relative brain size exceeds earlier Homo, yet is substantially lower than in final glacial H. sapiens and Homo neanderthalensis. A final leap in absolute and relative brain size in Homo (300,000–138,000 years) occurred independent of any observed increase in body mass and implies a different selective mediator to that operating on brain size increases observed in earlier Homo.     

Chronologie du Paléolithique supérieur dans le Nord-Est de la principale île du Japon

Palaeolithic archaeology in Tohoku region has long been discussed on constructing chronology, however it is difficult to build reliable chronological order because of poor stratigraphic excavations. In recent radiocarbon dating has advanced. In this paper I discuss the relation between chronology and radiocarbon dating in Tohoku region. At first, I categorize the Palaeolithic industries and establish the chronology by analyzing tool typology, lithic technology, and stratigraphic data. I correlate it with radiocarbon data from sites in Tohoku region. The result of analysis shows that Upper Palaeolithic industries are divided into 18 categories and 8 periods on chronology. The calibration curve IntCal 13 indicated that oldest Early Upper Palaeolithic site appeared around 37,000 cal BP, and late Upper Palaeolithic started about 27,000 cal BP. The pottery first appeared as far back as around 16,000 cal BP. Now we do not have enough radiocarbon data, so we have to gather and examine more ¹⁴C data.     

Synthesis and antioxidant evaluation of (S,S)- and (R,R)-secoisolariciresinol diglucosides (SDGs)

Secoisolariciresinol diglucosides (SDGs) (S,S)-SDG-1 (major isomer in flaxseed) and (R,R)-SDG-2 (minor isomer in flaxseed) were synthesized from vanillin via secoisolariciresinol (6) and glucosyl donor 7 through a concise route that involved chromatographic separation of diastereomeric diglucoside derivatives (S,S)-8 and (R,R)-9. Synthetic (S,S)-SDG-1 and (R,R)-SDG-2 exhibited potent antioxidant properties (EC₅₀ = 292.17 ± 27.71 μM and 331.94 ± 21.21 μM, respectively), which compared well with that of natural (S,S)-SDG-1 (EC₅₀ = 275.24 ± 13.15 μM). These values are significantly lower than those of ascorbic acid (EC₅₀ = 1129.32 ± 88.79 μM) and α-tocopherol (EC₅₀ = 944.62 ± 148.00 μM). Compounds (S,S)-SDG-1 and (R,R)-SDG-2 also demonstrated powerful scavenging activities against hydroxyl [natural (S,S)-SDG-1: 3.68 ± 0.27; synthetic (S,S)-SDG-1: 2.09 ± 0.16; synthetic (R,R)-SDG-2: 1.96 ± 0.27], peroxyl [natural (S,S)-SDG-1: 2.55 ± 0.11; synthetic (S,S)-SDG-1: 2.20 ± 0.10; synthetic (R,R)-SDG-2: 3.03 ± 0.04] and DPPH [natural (S,S)-SDG-1: EC₅₀ = 83.94 ± 2.80 μM; synthetic (S,S)-SDG-1: EC₅₀ = 157.54 ± 21.30 μM; synthetic (R,R)-SDG-2: EC₅₀ = 123.63 ± 8.67 μM] radicals. These results confirm previous studies with naturally occurring (S,S)-SDG-1 and establish both (S,S)-SDG-1 and (R,R)-SDG-2 as potent antioxidants and free radical scavengers for potential in vivo use.     

Effect of different levels of concentrate allowances on rumen fluid pH,nutrient digestion,nitrogen retention and growth performance of weaner lambs

This experiment was conducted for 90 d to assess the effect of feeding graded levels of concentrate allowance on rumen fermentation characteristics, performance and nutrient utilisation of weaner lambs on restricted or high concentrate allowance using 60 weaner lambs of initial average live weight of 13.90 kg BW in a randomized design. The experimental treatments were 15 or 25 g kg⁻¹ BW or ad libitum concentrate allowance. Roughage source which contained Khejri (Prosopis cineratia) and Siris (Albizia lebback) leaves in 50:50 ratio was offered ad libitum to all the animals. Lambs supplemented with 15 g or ad libitum concentrate had similar dry matter intake (4.2 kg/100 kg BW) but significantly (p < 0.01) lower than 25 g concentrate supplemented group (4.9 kg/100 kg BW). Organic matter and CP intakes increased with increasing concentrate supplementation. Apparent digestibilities of dry matter, organic matter, CP, NDF, ADF and cellulose were significantly (p < 0.01) higher in ad libitum concentrate supplemented than 15 and 25 g concentrate supplemented lambs. Daily ME intake was significantly (p < 0.05) higher in 25 g and ad libitum concentrate supplemented lambs while ME intake kg⁻¹ gain was lower in ad libitum concentrate supplemented lambs (57 MJ kg⁻¹ gain) than those supplemented with 15 or 25 g concentrate (91 MJ kg⁻¹ gain). Generally, average daily gain increased with increasing levels of concentrate supplementation. Ad libitum concentrate supplemented lambs had significantly (p < 0.01) higher daily gains (151 g) than 15 and 25 g concentrate supplemented lambs (77 and 98 g, respectively). Feed efficiency was similar for 15 and 25 g concentrate supplemented lambs but significantly (p < 0.01) lower than the ad libitum concentrate supplemented lambs. All animals were in positive N-balance and the N-balance increased with increasing concentrate supplementation. Mean rumen fluid pH was significantly (6.6, p < 0.01) lower in ad libitum concentrate supplemented lambs compared to 15 or 25 g concentrate fed lambs (6.9). Rumen NH₃-N and total-N-concentrations peaked at 3 h post-feeding. Optimum rumen fluid pH, better nutrient digestibilities, higher N-retention improved growth by 49% of ad libitum concentrate fed lambs.