Low-Weight Primes for Lightweight Elliptic Curve Cryptography on 8-bit AVR Processors

Small 8-bit RISC processors and micro-controllers based on the AVR instruction set architecture are widely used in the embedded domain with applications ranging from smartcards over control systems to wireless sensor nodes. Many of these applications require asymmetric encryption or authentication, which has spurred a body of research into implementation aspects of Elliptic Curve Cryptography (ECC) on the AVR platform. In this paper, we study the suitability of a special class of finite fields, the so-called Optimal Prime Fields (OPFs), for a "lightweight" implementation of ECC with a view towards high performance and security. An OPF is a finite field Fp defined by a prime of the form p = u*2^k + v, whereby both u and v are "small" (in relation to 2^k) so that they fit into one or two registers of an AVR processor. OPFs have a low Hamming weight, which allows for a very efficient implementation of the modular reduction since only the non-zero words of p need to be processed. We describe a special variant of Montgomery multiplication for OPFs that does not execute any input-dependent conditional statements (e.g. branch instructions) and is, hence, resistant against certain side-channel attacks. When executed on an Atmel ATmega processor, a multiplication in a 160-bit OPF takes just 3237 cycles, which compares favorably with other implementations of 160-bit modular multiplication on an 8-bit processor. We also describe a performance-optimized and a security-optimized implementation of elliptic curve scalar multiplication over OPFs. The former uses a GLV curve and executes in 4.19M cycles (over a 160-bit OPF), while the latter is based on a Montgomery curve and has an execution time of approximately 5.93M cycles. Both results improve the state-of-the-art in lightweight ECC on 8-bit processors

Glutamate mediated metabolic neutralization mitigates propionate toxicity in intracellular Mycobacterium tuberculosis

Metabolic networks in biological systems are interconnected, such that malfunctioning parts can be corrected by other parts within the network, a process termed adaptive metabolism. Unlike Bacillus Calmette-Guérin (BCG), Mycobacterium tuberculosis (Mtb) better manages its intracellular lifestyle by executing adaptive metabolism. Here, we used metabolomics and identified glutamate synthase (GltB/D) that converts glutamine to glutamate (Q → E) as a metabolic effort used to neutralize cytoplasmic pH that is acidified while consuming host propionate carbon through the methylcitrate cycle (MCC). Methylisocitrate lyase, the last step of the MCC, is intrinsically downregulated in BCG, leading to obstruction of carbon flux toward central carbon metabolism, accumulation of MCC intermediates, and interference with GltB/D mediated neutralizing activity against propionate toxicity. Indeed, vitamin B12 mediated bypass MCC and additional supplement of glutamate led to selectively correct the phenotypic attenuation in BCG and restore the adaptive capacity of BCG to the similar level of Mtb phenotype. Collectively, a defective crosstalk between MCC and Q → E contributes to attenuation of intracellular BCG. Furthermore, GltB/D inhibition enhances the level of propionate toxicity in Mtb. Thus, these findings revealed a new adaptive metabolism and propose GltB/D as a synergistic target to improve the antimicrobial outcomes of MCC inhibition in Mtb

Aspek Moral Dalam Novel Nebula Karya Tere-Liye : Tinjauan Sosiologi Sastra Dan Implementasi Sebagai Bahan Ajar Di Sma

Penelitian ini bertujuan untuk (1) mendeskripsikan struktur pembangun novel Nebula karya Tere-Liye, (2) mendeskripsikan aspek moral yang terkandung dalam novel Nebula karya Tere-Liye dan (3) mendeskripsikan implementasi hasil penelitian dalam pembelajaran sastra di SMA. Penelitian ini menggunakan metode deskriptif kualitatif. Sumber data yang diperoleh dari novel Nebula karya Tere-Liye yang berjumlah 374 halaman. Teknik pengumpulan data menggunakan teknik pustaka, teknik simak dan catat. Teknik analisis data dalam penelitian ini di lakukan menggunakan metode semiotik, dengan teknik membaca heuristik dan hermeneutik. Hasil penelitian ini adalah : alur yang di gunakan Tere-Liye dalam novel Nebula karya Tere-Liye ini adalah maju (progresif). Tokoh yang di hadirkan dalam novel ini adalah Selena, Mata, Tazk, Paman Raff, Bibi Leh, Boh, Ev, Lumpu, Kosong. Latar tempat dalam novel ini yaitu Kota Tishri, Kampus ABTT, Klan Nebula. Latar waktu dalam novel ini yaitu pagi, siang dan malam. Analisis aspek moral dalam novel Nebula karya Tere-Liye dengan menggunakan pendekatan sosiologi sastra di temukan adanya (1) aspek moral kejujuran yang di tunjukan pada tokoh utama yaitu Selena yang mengaku pada Tazk dan Mata bahwa dia lah yang mencuri cawan itu dan ingin meninggalkan kedua temannya dan mermbuat menjadi kekacauan, (2) aspek menjadi diri sendiri yang ditunjukan pada tokoh Kosong perempuan tua berambut putih yang mempuyai perilaku yang tidak mudah terpengaruh pada orang lain, (3) aspek bertanggung jawab yang di tunjukkan pada Selena yang bersedia melakukan apa saja agar tidak terjadi kekacauan lagi di Klan Nebula, (4) aspek kemandirian yang di tunjukan pada tokoh Mata sahabat Selena dia selalu mempuyai prinsip dengan dirinya sendiri, (5) aspek keberanian moral yang di tunjukkan pada tokoh Mata yang tetap mempertahankan suara hatinya bahwa dia tetap baik hati dan tulus kepada sahabatnya yaitu Selena, (6) aspek kerendahan hati yang di tunjukkan pada semua individu atau penduduk di Klan Nebula yang semuanya merupakan orang-orang yang sangat apa adanya, sederhana dan jujur dalam hal apapun dan (7) aspek kritis yang di tunjukkan pada tokoh Tazk yang memberikan saran kepada Selena agar tidak lagi mengambil cawan keabadian tersebut. Berdasarkan hasil analisi di atas, dapat disimpulkan bahwa novel Nebula karya Tere-Liye layak digunakan sebagai bahan pembelajaran sastra di SMA kelas XII, KD 3.8. Dari segi bahasa, perkembangan psikologi, dan latar belakang budaya, novel ini cocok untuk dijadikan bahan pembelajaran di kelas

Dynamic Modeling of Cell Migration and Spreading Behaviors on Fibronectin Coated Planar Substrates and Micropatterned Geometries

An integrative cell migration model incorporating focal adhesion (FA) dynamics, cytoskeleton and nucleus remodeling, actin motor activity, and lamellipodia protrusion is developed for predicting cell spreading and migration behaviors. This work is motivated by two experimental works: (1) cell migration on 2-D substrates under various fibronectin concentrations and (2) cell spreading on 2-D micropatterned geometries. These works suggest (1) cell migration speed takes a maximum at a particular ligand density (~1140 molecules/µm2) and (2) that strong traction forces at the corners of the patterns may exist due to combined effects exerted by actin stress fibers (SFs). The integrative model of this paper successfully reproduced these experimental results and indicates the mechanism of cell migration and spreading. In this paper, the mechanical structure of the cell is modeled as having two elastic membranes: an outer cell membrane and an inner nuclear membrane. The two elastic membranes are connected by SFs, which are extended from focal adhesions on the cortical surface to the nuclear membrane. In addition, the model also includes ventral SFs bridging two focal adhesions on the cell surface. The cell deforms and gains traction as transmembrane integrins distributed over the outer cell membrane bond to ligands on the ECM surface, activate SFs, and form focal adhesions. The relationship between the cell migration speed and fibronectin concentration agrees with existing experimental data for Chinese hamster ovary (CHO) cell migrations on fibronectin coated surfaces. In addition, the integrated model is validated by showing persistent high stress concentrations at sharp geometrically patterned edges. This model will be used as a predictive model to assist in design and data processing of upcoming microfluidic cell migration assays

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Effect of Peer Health Workers on AIDS Care in Rakai, Uganda: A Cluster-Randomized Trial

Human resource limitations are a challenge to the delivery of antiretroviral therapy (ART) in low-resource settings. We conducted a cluster randomized trial to assess the effect of community-based peer health workers (PHW) on AIDS care of adults in Rakai, Uganda.15 AIDS clinics were randomized 2:1 to receive the PHW intervention (n = 10) or control (n = 5). PHW tasks included clinic and home-based provision of counseling, clinical, adherence to ART, and social support. Primary outcomes were adherence and cumulative risk of virologic failure (>400 copies/mL). Secondary outcomes were virologic failure at each 24 week time point up to 192 weeks of ART. Analysis was by intention to treat. From May 2006 to July 2008, 1336 patients were followed. 444 (33%) of these patients were already on ART at the start of the study. No significant differences were found in lack of adherence (<95% pill count adherence risk ratio [RR] 0.55, 95% confidence interval [CI] 0.23-1.35; <100% adherence RR 1.10, 95% CI 0.94-1.30), cumulative risk of virologic failure (RR 0.81, 95% CI 0.61-1.08) or in shorter-term virologic outcomes (24 week virologic failure RR 0.93, 95% CI 0.65-1.32; 48 week, RR 0.83, 95% CI 0.47-1.48; 72 week, RR 0.81, 95% CI 0.44-1.49). However, virologic failure rates >or=96 weeks into ART were significantly decreased in the intervention arm compared to the control arm (96 week failure RR 0.50, 95% CI 0.31-0.81; 120 week, RR 0.59, 95% CI 0.22-1.60; 144 week, RR 0.39, 95% CI 0.16-0.95; 168 week, RR 0.30, 95% CI 0.097-0.92; 192 week, RR 0.067, 95% CI 0.0065-0.71).A PHW intervention was associated with decreased virologic failure rates occurring 96 weeks and longer into ART, but did not affect cumulative risk of virologic failure, adherence measures, or shorter-term virologic outcomes. PHWs may be an effective intervention to sustain long-term ART in low-resource settings.ClinicalTrials.gov NCT00675389

Antipsychotic withdrawal symptoms: Phenomenology and pathophysiology

The authors review the literature discribing non-dyskinetic antipsychotic withdrawal phenomena. Withdrawal of these agents can cause nausea, emesis, anorexia, diarrhea, rhinorrhea, diaphoresis, myalgia, paresthesia, anxiety, agitation, restlessness, and insomnia. Psychotic relapse is often presaged by increased anxiety, agitation, restlessness and insomnia, but the temporal relationship of these prodromal symptoms to reduction in the dosage or discontinuation of neuroleptics distinguishes them from the effects of abrupt withdrawal.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65190/1/j.1600-0447.1988.tb05116.x.pd

Early Life Events Carry Over to Influence Pre-Migratory Condition in a Free-Living Songbird

Conditions experienced during development can have long-term consequences for individual success. In migratory songbirds, the proximate mechanisms linking early life events and survival are not well understood because tracking individuals across stages of the annual cycle can be extremely challenging. In this paper, we first use a 13 year dataset to demonstrate a positive relationship between 1st year survival and nestling mass in migratory Savannah sparrows (Passerculus sandwichensis). We also use a brood manipulation experiment to show that nestlings from smaller broods have higher mass in the nest relative to individuals from larger broods. Having established these relationships, we then use three years of field data involving multiple captures of individuals throughout the pre-migratory period and a multi-level path model to examine the hypothesis that conditions during development limit survival during migration by affecting an individual's ability to accumulate sufficient lean tissue and fat mass prior to migration. We found a positive relationship between fat mass during the pre-migratory period (Sept–Oct) and nestling mass and a negative indirect relationship between pre-migratory fat mass and fledging date. Our results provide the first evidence that conditions during development limit survival during migration through their effect on fat stores. These results are particularly important given recent evidence showing that body condition of songbirds at fledging is affected by climate change and anthropogenic changes to landscape structure

The validation of a new measure quantifying the social quality of life of ethnically diverse older women: two cross-sectional studies

<p>Abstract</p> <p>Background</p> <p>To our knowledge, the available psychometric literature does not include an instrument for the quantification of social quality of life among older women from diverse ethnic backgrounds. To address the need for a tool of this kind, we conducted two studies to assess the initial reliability and validity of a new instrument. The latter was created specifically to quantify the contribution of a) social networks and resources (e.g., family, friends, and community) as well as b) one's perceived power and respect within family and community to subjective well-being in non-clinical, ethnically diverse populations of older women.</p> <p>Methods</p> <p>In Study 1, we recruited a cross-sectional sample of primarily non-European-American older women (<it>N </it>= 220) at a variety of community locations. Participants were administered the following: a short screener for dementia; a demographic list; an initial pool of 50 items from which the final items of the new Older Women's Social Quality of Life Inventory (OWSQLI) were to be chosen (based on a statistical criterion to apply to the factor analysis findings); the Single Item Measure of Social Support (SIMSS); and the Medical Outcome Study 36-item Short-Form Health Survey (MOS SF-36). Study 2 was conducted on a second independent sample of ethnically diverse older women. The same recruitment strategies, procedures, and instruments as those of Study 1 were utilized in Study 2, whose sample was comprised of 241 older women with mostly non-European-American ethnic status.</p> <p>Results</p> <p>In Study 1, exploratory factor analysis of the OWSQLI obtained robust findings: the total variance explained by one single factor with the final selection of 22 items was over 44%. The OWSQLI demonstrated strong internal consistency (<it>α </it>= .92, <it>p </it>< .001), adequate criterion validity with the SIMSS (<it>r </it>= .33; <it>p </it>< .01), and (as expected) moderate concurrent validity with the MOS SF-36 for both physical (<it>r </it>= .21; <it>p </it>< .01) and mental (<it>r </it>= .26; <it>p </it>< .01) quality of life. In order to confirm the validity of the 22-item OWSQLI scale that emerged from Study 1 analyses, we replicated those analyses in Study 2, although using confirmatory factor analysis. The total variance accounted for by one factor was about 42%, again quite high and indicative of a strong single-factor solution. Study 2 data analyses yielded the same strong reliability findings (i.e., <it>α </it>= .92, <it>p </it>< .001). The 22-item OWSQLI was correlated with the SIMSS (<it>r </it>= .27, <it>p </it>< .001) in the expected direction. Finally, correlations with the MOS SF- 36 demonstrated moderate concurrent validity for physical (<it>r </it>= .14; <it>p </it>< .01) and mental (<it>r </it>= .18; <it>p </it>< .01) quality of life, as expected.</p> <p>Conclusions</p> <p>The findings of these two studies highlight the potential for our new tool to provide a valid measure of older women's social quality of life, yet they require duplication in longitudinal research. Interested clinicians should consider using the OWSQLI in their assessment battery to identify older women's areas of lower versus higher social quality of life, and should establish the maximization of patients' social quality of life as an important therapeutic goal, as this variable is significantly related to both physical and mental health.</p