391 research outputs found

    Synthesis of electrical networks interconnecting PZT actuators to damp mechanical vibrations

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    This paper proves that it is possible to damp mechanical vibrations of some beam frames by means of piezoelectric actuators interconnected via passive networks. We create a kind of electromechanical wave guide where the electrical velocity group equals the mechanical one thus enabling an electromechanical energy transfer. Numerical simulations are presented which prove the technical feasibility of proposed deviceComment: International Symposium on Applied Electromagnetics and Mechanics in honor of Professor K.Miya, Tokyo: 2000. 9 page

    A study of the stress wave factor technique for nondestructive evaluation of composite materials

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    The acousto-ultrasonic method of nondestructive evaluation is an extremely sensitive means of assessing material response. Efforts continue to complete the understanding of this method. In order to achieve the full sensitivity of the technique, extreme care must be taken in its performance. This report provides an update of the efforts to advance the understanding of this method and to increase its application to the nondestructive evaluation of composite materials. Included are descriptions of a novel optical system that is capable of measuring in-plane and out-of-plane displacements, an IBM PC-based data acquisition system, an extensive data analysis software package, the azimuthal variation of acousto-ultrasonic behavior in graphite/epoxy laminates, and preliminary examination of processing variation in graphite-aluminum tubes

    PCR for the detection of pathogens in neonatal early onset sepsis.

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    BACKGROUND: A large proportion of neonates are treated for presumed bacterial sepsis with broad spectrum antibiotics even though their blood cultures subsequently show no growth. This study aimed to investigate PCR-based methods to identify pathogens not detected by conventional culture. METHODS: Whole blood samples of 208 neonates with suspected early onset sepsis were tested using a panel of multiplexed bacterial PCRs targeting Streptococcus pneumoniae, Streptococcus agalactiae (GBS), Staphylococcus aureus, Streptococcus pyogenes (GAS), Enterobacteriaceae, Enterococcus faecalis, Enterococcus faecium, Ureaplasma parvum, Ureaplasma urealyticum, Mycoplasma hominis and Mycoplasma genitalium, a 16S rRNA gene broad-range PCR and a multiplexed PCR for Candida spp. RESULTS: Two-hundred and eight samples were processed. In five of those samples, organisms were detected by conventional culture; all of those were also identified by PCR. PCR detected bacteria in 91 (45%) of the 203 samples that did not show bacterial growth in culture. S. aureus, Enterobacteriaceae and S. pneumoniae were the most frequently detected pathogens. A higher bacterial load detected by PCR was correlated positively with the number of clinical signs at presentation. CONCLUSION: Real-time PCR has the potential to be a valuable additional tool for the diagnosis of neonatal sepsis

    VISUALIZING THE DATA VISUALIZATION NETWORK: THE DVMAP PROJECT

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    Data visualization is a familiar buzzword. Experts in the humanities, social and natural sciences, as well as technology, along with semi-experts and the general public, reach people everywhere with trends and conclusions drawn from visualized data. Governments, industries, businesses, sciences, marketers, academics, students and others value data visualization methods and tools as critical, applicable tools for understanding the world, which provide rich information analyses for specialists and generalists alike. Unfortunately, no single resource offers a space where people working in the multifaceted field of data visualization can share projects they are working on, tools they created, educational opportunities in the field, nor where they (and their work) are situated geographically. A research group at New Mexico Institute of Mining and Technology seeks to fill this gap with a repository of data visualization resources called ―Data Visualization Map (DVMap).‖ The DVMap is an interactive network data and geographic representation graph that provides a data visualization space for people across the world to share, view and/or collaborate on projects and publications; tools deployed or under development; educational opportunities in data visualization, such as formal programs, summer seminars, conferences; and the geographical locations of the users, projects, tools and educational opportunities. Given the necessity of this repository, this paper outlines the structure, underlying methodology, and anticipated outcomes for the DVMap data visualization network. The paper also accounts for limitations of the project and the potential problems of creating a map that wants to share work – especially work in progress – with everyone

    Axial jerks: a clinical spectrum ranging from propriospinal to psychogenic myoclonus

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    Propriospinal myoclonus (PSM) is a rare disorder with repetitive flexor, arrhythmic jerks of the trunk, hips and knees. Its generation is presumed to relay in the spinal cord. We report a case series of 35 consecutive patients with jerks of the trunk referred as possible PSM to a tertiary referral center for movement disorders. We review classical PSM features as well as psychogenic and tic characteristics. In our case series, secondary PSM was diagnosed in one patient only. 34 patients showed features suggestive of a psychogenic origin of axial jerks. Diagnosis of psychogenic axial jerks was based on clinical clues without additional investigations (n = 8), inconsistent findings at polymyography (n = 15), regular eye blinking preceding jerks (n = 2), or the presence of a Bereitschaftspotential (BP) (n = 9). In addition, several tic characteristics were noted. Almost all patients referred with possible PSM in our tertiary referral clinic had characteristics suggesting a psychogenic origin even in the presence of a classic polymyography pattern or in the absence of a BP. Clinical overlap with adult-onset tics seems to exist

    Utilization of life feed Alona sp., Boiled Egg Yolk and Commercial Feed Toward Survival Rate of Betta Fish Larvae

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    The purpose of this study was to find out the survival rates of betta fish larvae (cupang) that were given life feed Alona sp., boiled egg yolk and commercial feed for 21 days. Data analysis was performed by one-way ANOVA, and continued with BNJ (Tukey) test. The result of the survival rate is as follow treatment with life feed Alona sp. 56%, treatment with boiled egg yolk 26%, and treatment with commercial feed 0%. The results of statistical tests show there are significant differences.  Significant value p <.0002 (<.05). Water quality parameter measured during the study was temperature of 26 ºC.Keywords: betta fish larvae, life feed, Alona sp., survival rateABSTRAKTujuan penelitian ini adalah untuk mendapatkan laju kelangsungan hidup larva ikan betta (cupang) yang dibeerikan pakan alami Alona sp., rebusan kuning telur dan pakan komersil selama 21 hari.  Analisis data dilakukan dengan ANOVA one way, dan dilanjutkan dengan uji BNJ (Tukey).  Hasil laju kelangsungan hidup adalah sebagai berikut, perlakuan dengan pakan alami Alona sp. 56%, perlakuan dengan rebusan kuning telur 26%, dan perlakuan dengan pakan komersil 0%.  Hasil uji statistik menunjukan adanya perbedaan yang nyata.  Nilai signifikan p <.0002 (<.05).  Parameter kualitas air yang diukur selama penelitian adalah suhu 26ºC.Keywords: larva ikan betta, pakan alami, Alona sp., kelangsungan hidu

    Phytoplankton Community Structure in Seagrass Beds in Tiwoho Village, North Minahasa Regency

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    This research was carried out from May to July 2022. A sampling at the study site included seawater for the needs of plankton identification as well as the measurement of water nitrate &amp; phosphate levels and measurement of physical and chemical parameters such as temperature, pH, salinity and dissolved oxygen which were carried out on an ongoing basis In situ (in the field). The technique for determining plankton sampling was carried out purposively, namely with certain considerations to obtain samples that represent the research location area. Plankton sampling was carried out horizontally using a plankton net. Sample bottles containing seawater were identified at the Marine Biology Laboratory, Faculty of Fisheries and Marine Sciences. The composition of the phytoplankton found in the Tiwoho seagrass bed ecosystem consists of three classes, namely the Bacillariophyceae, Dynophyceae, and Cyanophyceae classes, with 28 genera. The results of chopped phytoplankton are expressed in Cells/l. The qualitative determination of plankton is made up to the genus level. The composition of the phytoplankton found in the Tiwoho seagrass bed ecosystem consists of three classes, namely the Bacillariophyceae, Dynophyceae, and Cyanophyceae classes, with 28 genera. The results of calculating the abundance of phytoplankton in the Tiwoho seagrass ecosystem are in the range of 29 - 66 cells/l. The highest abundance was found at station two, namely 66 cells/l with 21 genera, then station three (65 cells/l) with 24 genera, and station one (29 cells/l) with a total of 23 genera. The diversity index of seagrass beds in Tiwoho waters is in the range of 1.9330 - 2.4083, which means that community stability is categorized as moderate. The uniformity index is in the range of 0.4614 - 0.7154, this means that the uniformity between species is relatively the same, or the difference is not striking. While the domination index is in the range of 0.1494 - 0.2404, it means that the condition of the community structure is stable, and there is no ecological pressure (stress) on biota. Keywords: Phytoplankton, Biological Index, Abundance, Environmental parameters Abstrak Penelitian ini dilaksanakan pada bulan Mei sampai bulan Juli 2022. Pengambilan sampel di lokasi penelitian meliputi air laut untuk kebutuhan identifikasi fitoplankton dan pengukuran kadar nitrat, fosfat perairan serta pengukuran parameter fisika kimia seperti suhu, pH, salinitas dan oksigen terlarut yang dilakukan secara In situ (di lapangan). Teknik penentuan pengambilan sampel plankton dilakukan secara purposif yaitu dengan pertimbangan tertentu untuk mendapatkan sampel yang mewakili area lokasi penelitian. Pengambilan sampel plankton dilakukan secara horisontal dengan menggunakan plankton net. Sampel plankton diberi pengawet formalin 4% dan&nbsp; diidentifikasi di laboratorium Biologi Kelautan Fakultas Perikanan dan Ilmu Kelautan. Komposisi fitoplankton yang dijumpai di ekosistem padang lamun Perairan Tiwoho terdiri dari tiga kelas yaitu kelas Bacillariophyceae, Dynophyceae, dan Cyanophyceae, dengan 28 genera. Hasil perhitungan kelimpahan fitoplankton di ekosistem padang lamun Perairan Tiwoho berada di kisaran 29 - 66 sel/l. Kelimpahan tertinggi ditemukan di stasiun dua (depan kampung) yaitu 66 sel/l dengan 21 genera, kemudian stasiun tiga (depan dermaga) yaitu 65 sel/l dengan 24 genera, dan stasiun satu (ujung kampung) sebanyak 29 sel/l dengan jumlah 23 genera. Indeks keanekaragaman ekosistem padang lamun Perairan Tiwoho berada pada kisaran 1,9330 - 2,4083, yang berarti stabilitas komunitas dikategorikan sedang. Indeks keseragaman yaitu pada kisaran 0,4614 - 0,7154, ini berarti keseragaman antar spesies relatif sama, atau perbedaannya tidak menyolok. Sedangkan indeks dominasi yaitu pada kisaran&nbsp; 0,1494 - 0,2404, berarti kondisi struktur komunitas dalam keadaan stabil, dan tidak terjadi tekanan ekologi (stress) terhadap biota. Kata kunci: Fitoplankton, Indeks Biologi, Kelimpahan, Parameter lingkunga
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