Dynamic subcellular translocation of V-type H+ -ATPase is essential for biomineralization of the diatom silica cell wall.

Diatom cell walls, called frustules, are main sources of biogenic silica in the ocean and their intricate morphology is an inspiration for nanoengineering. Here we show dynamic aspects of frustule biosynthesis involving acidification of the silica deposition vesicle (SDV) by V-type H+  ATPase (VHA). Transgenic Thalassiosira pseudonana expressing the VHA B subunit tagged with enhanced green fluorescent protein (VHAB -eGFP) enabled subcellular protein localization in live cells. In exponentially growing cultures, VHAB -eGFP was present in various subcellular localizations including the cytoplasm, SDVs and vacuoles. We studied the role of VHA during frustule biosynthesis in synchronized cell cultures of T. pseudonana. During the making of new biosilica components, VHAB -eGFP first localized in the girdle band SDVs, and subsequently in valve SDVs. In single cell time-lapse imaging experiments, VHAB -eGFP localization in SDVs precluded accumulation of the acidotropic silica biomineralization marker PDMPO. Furthermore, pharmacological VHA inhibition prevented PDMPO accumulation in the SDV, frustule biosynthesis and cell division, as well as insertion of the silicalemma-associated protein SAP1 into the SDVs. Finally, partial inhibition of VHA activity affected the nanoscale morphology of the valve. Altogether, these results indicate that VHA is essential for frustule biosynthesis by acidifying the SDVs and regulating the insertion of other structural proteins into the SDV

Timing is everything: Drivers of interannual variability in blue whale migration.

Blue whales need to time their migration from their breeding grounds to their feeding grounds to avoid missing peak prey abundances, but the cues they use for this are unknown. We examine migration timing (inferred from the local onset and cessation of blue whale calls recorded on seafloor-mounted hydrophones), environmental conditions (e.g., sea surface temperature anomalies and chlorophyll a), and prey (spring krill biomass from annual net tow surveys) during a 10 year period (2008-2017) in waters of the Southern California Region where blue whales feed in the summer. Colder sea surface temperature anomalies the previous season were correlated with greater krill biomass the following year, and earlier arrival by blue whales. Our results demonstrate a plastic response of blue whales to interannual variability and the importance of krill as a driving force behind migration timing. A decadal-scale increase in temperature due to climate change has led to blue whales extending their overall time in Southern California. By the end of our 10-year study, whales were arriving at the feeding grounds more than one month earlier, while their departure date did not change. Conservation strategies will need to account for increased anthropogenic threats resulting from longer times at the feeding grounds

Similarity search in the blink of an eye with compressed indices

Nowadays, data is represented by vectors. Retrieving those vectors, among millions and billions, that are similar to a given query is a ubiquitous problem of relevance for a wide range of applications. In this work, we present new techniques for creating faster and smaller indices to run these searches. To this end, we introduce a novel vector compression method, Locally-adaptive Vector Quantization (LVQ), that simultaneously reduces memory footprint and improves search performance, with minimal impact on search accuracy. LVQ is designed to work optimally in conjunction with graph-based indices, reducing their effective bandwidth while enabling random-access-friendly fast similarity computations. Our experimental results show that LVQ, combined with key optimizations for graph-based indices in modern datacenter systems, establishes the new state of the art in terms of performance and memory footprint. For billions of vectors, LVQ outcompetes the second-best alternatives: (1) in the low-memory regime, by up to 20.7x in throughput with up to a 3x memory footprint reduction, and (2) in the high-throughput regime by 5.8x with 1.4x less memory

Spatio-temporal patterns of beaked whale echolocation signals in the North Pacific.

At least ten species of beaked whales inhabit the North Pacific, but little is known about their abundance, ecology, and behavior, as they are elusive and difficult to distinguish visually at sea. Six of these species produce known species-specific frequency modulated (FM) echolocation pulses: Baird's, Blainville's, Cuvier's, Deraniyagala's, Longman's, and Stejneger's beaked whales. Additionally, one described FM pulse (BWC) from Cross Seamount, Hawai'i, and three unknown FM pulse types (BW40, BW43, BW70) have been identified from almost 11 cumulative years of autonomous recordings at 24 sites throughout the North Pacific. Most sites had a dominant FM pulse type with other types being either absent or limited. There was not a strong seasonal influence on the occurrence of these signals at any site, but longer time series may reveal smaller, consistent fluctuations. Only the species producing BWC signals, detected throughout the Pacific Islands region, consistently showed a diel cycle with nocturnal foraging. By comparing stranding and sighting information with acoustic findings, we hypothesize that BWC signals are produced by ginkgo-toothed beaked whales. BW43 signal encounters were restricted to Southern California and may be produced by Perrin's beaked whale, known only from Californian waters. BW70 signals were detected in the southern Gulf of California, which is prime habitat for Pygmy beaked whales. Hubb's beaked whale may have produced the BW40 signals encountered off central and southern California; however, these signals were also recorded off Pearl and Hermes Reef and Wake Atoll, which are well south of their known range

Life adversities of clients seeking advice for suicidal ideation from an online peer counseling service: Characteristics and associations with outcomes

Objective: [U25] Germany is a low-threshold, anonymous and free-of-charge online suicide prevention service for people up to 25 years of age. Its special feature is that counseling is provided by trained and continuously supervised voluntary peers. This study addresses the following research questions: (1) Which life adversities are reported by the clients of [U25]? (2) Are the life adversities intercorrelated? (3) According to patients, do life adversities change during the counseling process? (4) What are the associations between life adversities and outcome measures (e.g., reduction in suicidality or improvement in general situation)? Method: Data was collected through an online survey (n = 318). To measure psychological burden, the presence of 16 life adversities (e.g., problems in relationships) was assessed retrospectively. As the dependent variable, the change in suicidality was measured by means of three newly created items. In addition, a short form of the Bochum Change Questionnaire 2000 (BCQ 2000) was used to assess the patients’ subjectively perceived change due to counseling. Results: Regarding life adversities, the clients were heavily burdened. Throughout the course of counseling, many clients’ situations improved, at least concerning several adversities. Some life adversities significantly correlate with each other, but the correlation is mostly small to moderate. Suicidality is positively correlated with self-harming behaviors and loss of someone close to the advice seekers. Conclusions: Possible starting points for improving online counseling for suicidal adolescents and young adults are discussed

Brainspotting – the efficacy of a new therapy approach for the treatment of Posttraumatic Stress Disorder in comparison to Eye Movement Desensitization and Reprocessing

Objective: This study aims at determining the efficacy of the new therapy approach Brainspotting (BSP) in comparison to the established Eye Movement Desensitization and Reprocessing (EMDR) approach for the treatment of Posttraumatic Stress Disorder (PTSD). Method: The sample consisted of 76 adult seeking professional help after they have been affected by a traumatic event. Clients were either treated with three 60-minute sessions of EMDR (n=23) or BSP (n=53) according to a standard protocol. Primary outcomes assessed were self-reports of the severity of PTSD symptoms. Secondary outcomes included self-reported symptoms of depression and anxiety. Assessments were conducted at pretreatment, posttreatment and 6 month after the treatment. Results: Participants in both conditions showed significant reductions in PTSD symptoms. Effect sizes (Cohen’s d) from baseline to posttreatment concerning PTSD related symptoms were between 1.19 - 1.76 for clients treated with EMDR and 0.74 - 1.04 for clients treated with BSP. Conclusion: Our results indicate that Brainspotting seems to be an effective alternative therapeutic approach for clients who experienced a traumatic event and/or with PTSD

Open Posterior Reduction and Stabilization of AO Spine C3 Sacral Fractures.

AO Spine C3 sacral fractures are defined by separation of the spine including S1 from the pelvic ring and are usually result of a high-energy injury. Besides their high biomechanical instability and high rate of associated neurological impairment, these fractures are often extremely difficult to reduce due to severe bony impaction and dislocation. Additional difficulties in management of these fractures arise from only a thin-layer of soft-tissue coverage overlying the injured area

BLAST05: Power Spectra of Bright Galactic Cirrus at Submillimeter Wavelengths

We report multi-wavelength power spectra of diffuse Galactic dust emission from BLAST observations at 250, 350, and 500 microns in Galactic Plane fields in Cygnus X and Aquila. These submillimeter power spectra statistically quantify the self-similar structure observable over a broad range of scales and can be used to assess the cirrus noise which limits the detection of faint point sources. The advent of submillimeter surveys with the Herschel Space Observatory makes the wavelength dependence a matter of interest. We show that the observed relative amplitudes of the power spectra can be related through a spectral energy distribution (SED). Fitting a simple modified black body to this SED, we find the dust temperature in Cygnus X to be 19.9 +/- 1.3 K and in the Aquila region 16.9 +/- 0.7 K. Our empirical estimates provide important new insight into the substantial cirrus noise that will be encountered in forthcoming observations.Comment: Submitted to the Astrophysical Journal. Maps and other data are available at http://blastexperiment.info