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The variability of the northern westerlies has been considered as one of the key elements for modern and past climate evolution. Their multiscale behavior and underlying control mechanisms, however, are incompletely understood, owing to the complex dynamics of Atlantic sea-level pressures. Here, we present a multi-annually resolved record of the westerly drift over the past 6,500 years from northern Italy. In combination with more than 20 other westerly-sensitive records, our results depict the non-stationary westerly-affected regions over mainland Europe on multi-decadal to multi-centennial time scales, showing that the direction of the westerlies has changed with respect to the migrations of the North Atlantic centers of action since the middle Holocene. Our findings suggest the crucial role of the migrations of the North Atlantic dipole in modulating the westerly-affected domain over Europe, possibly modulated by Atlantic Ocean variability.

Naturally stalled replication forks are considered to cause structurally abnormal chromosomes in tumor cells. However, underlying mechanisms remain speculative, as capturing naturally stalled forks has been a challenge. Here, we captured naturally stalled forks in tumor cells and delineated molecular processes underlying the structural evolution of circular mini-chromosomes (double-minute chromosomes; DMs). Replication forks stalled on the DM by the co-directional collision with the transcription machinery for long non-coding RNA. RPA, BRCA2, and DNA polymerase eta (Polη) were recruited to the stalled forks. The recruitment of Polη was critical for replication to continue, as Polη knockdown resulted in DM loss. Rescued stalled forks were error-prone and switched replication templates repeatedly to create complex fusions of multiple short genomic segments. In mice, such complex fusions circularized the genomic region surrounding MYC to create a DM during tumorigenesis. Our results define a molecular path that guides stalled replication forks to complex chromosomal rearrangements.

Sea surface temperature (SST) variability in the south-eastern tropical Indian Ocean is crucial for rainfall variability in Indian Ocean rim countries. A large body of literature has focused on zonal variability associated with the Indian Ocean Dipole (IOD), but it is unclear whether meridional shifts in the position of the Intertropical Convergence Zone (ITCZ), which at present co-vary with the IOD, may also occur independently. We have developed a new, monthly resolved Sr/Ca record from a sub-fossil coral cored at Enggano Island (Indonesia, 5° S, 102° E). Core sections containing diagenetic phases are omitted from the SST reconstruction. U/Th dating shows that the Sr/Ca-based SST record extends from 1917–1868 and from 1861–1823 with a relative age uncertainty of ±2.4 years (2σ). At Enggano Island, coastal upwelling and cooling in austral spring is coupled to the position of the ITCZ, and impacts SST seasonality. The sub-fossil coral indicates an increase in SST seasonality due to enhanced austral spring cooling between 1917 and 1855, which we attribute to stronger SE winds and a northward shift in the position of the ITCZ in austral spring. A nearby sediment core indicates SST cooling and a shallowing of the thermocline prior to ~1930. These results are consistent with an increase in the North-South SST gradient in the eastern Indian Ocean calculated from historical temperature data, that is not seen in the zonal SST gradient. We conclude that the relationship between meridional and zonal variability in the eastern Indian Ocean is non-stationary and influenced by long-term temperature trends. [ABSTRACT FROM AUTHOR]

Introduction: Peripheral artery disease (PAD) is commonly observed in patients undergoing hemodialysis. PAD impairs the vasculature and leads to pathophysiologic changes in the skeletal muscles, causing physical function impairment and physical inactivity in general. However, it is unclear whether PAD adversely affects physical function and physical activity in patients on hemodialysis. Methods: We performed a cross‐sectional study with a retrospective review of the data to determine whether PAD is associated with impaired physical function and physical activity in patients undergoing hemodialysis. The study population comprised 310 patients and 88 healthy subjects. PAD was diagnosed based on an ankle‐brachial index of <1.00 in patients on hemodialysis. Measurements of physical function included maximum walking speed, muscle strength in the lower extremities, and balance while standing. Findings: Of the 310 patients, 84 (27.1%) had PAD. When patients undergoing hemodialysis were divided into those without PAD and those with PAD, both groups had poorer physical function and physical activity than the healthy control subjects. After adjustments for potential confounders, it was found that patients on hemodialysis with PAD had slower walking speed, poorer standing balance, and less physical activity than those without PAD. However, there was no significant difference in lower extremity muscle strength between the two groups. Discussion: PAD diagnosed based on an ankle‐brachial index of <1.00 was independently associated with impaired physical function and reduced physical activity in patients undergoing hemodialysis. [ABSTRACT FROM AUTHOR]

This study examines the effect of gender on marketing efficiency among maize producing households using data collected in the Dawuro zone, southern Ethiopia. Results indicate that the amount of maize assigned to the first ranked (most efficient) channel for male, female and joint decision-making households is significantly larger than that of the second, third, and fourth ranked channels, respectively. Significant results vary across gender categories at the same stage of marketing channel. Female decision-making households receive a lower producer price, as well as cover higher marketing costs and margins of middlemen, as compared to male and joint decision-makers at the same stage of the marketing channel. This study also found a limited financial ability for local institutions to establish maize storages in the study area. There is a need for an integrated agricultural marketing information system that would help female decision-making maize producers to better engage in available market opportunities. [ABSTRACT FROM AUTHOR]

A giant clam shell (Tridacna maxima) collected from the lagoon of Minicoy Island in the southern Lakshadweep Archipelago, India, was used for a high-resolution stable isotope (δ18O, δ13C) analysis. The results reveal a cyclic pattern in δ18Oshell values, interpreted as combined signatures of seasonal temperature and δ18Osw fluctuations over the period from 2004 to 2014. These δ18Oshell cycles are characterized by a slight background scatter governed by rainfall events leading to short-term and limited freshening of the water in the partly restricted lagoon. The most striking features of the isotope data are exceptionally negative outliers in δ18Oshell values beginning in mid-2010. This first anomalous isotope excursion is followed by a phase of lowered growth rates lasting until the beginning of 2011. It is observed that this sudden change in oxygen isotope composition and shell precipitation was caused by anomalous sea surface warming, which was previously documented for the region in 2010 and caused widespread coral bleaching throughout the Lakshadweep Archipelago. Even though several other negative excursions in δ18Oshell values follow, the cyclicity in the isotope signal and the growth rates become again more regular in the distal part of the shell, indicating a gradual recovery of the bivalve after the initial thermal stress event. The results reveal that even short high-temperature events can significantly perturb the biology of giant clams and require long recovery phases. This information is particularly significant for conservation efforts for this endangered bivalve group in a world with ongoing global warming. [ABSTRACT FROM AUTHOR]