Preliminary Study In Finding Bioelastomer Based On Vegetable Oil: Dimer Acid Preparation

Dimer acid is the main material in the synthesis of bioelastomer. The preparation of dimer acid from vegetable oil such as crude palm oil and jatropha seed oil via Diels-Alder reaction were investigated. The dimer acid based vegetable oil was obtained by reacting vegetable oil with 12% by weight of acrylic acid and 0.05 – 0.15% by weight of iodine catalyst at temperature 191.25 – 247.5 oC for 1 – 2 hours. Dimer acids were analyzed using Fourier transform infrared spectroscopy, degree of acidity and acid value determination. The results show that the degree acidity (pH) of dimer acid from crude palm oil and jatropha seed oil were 2.18 – 2.35 and 2.46 – 2.56, respectively. The acid value of dimer acid from palm oil is 89.07 – 90.07 mg KOH/g sample and acid value of dimer acid from the jatropha seed oil is 63.80 – 80.43 mg KOH/g sample. Although the acid value is still lower than the commercial dimer acid (Empol 1016), the FTIR results showed that both dimer acids had some dicarboxylic acid functional groups as appeared in Empol 1016. So both vegetable oils have potential as a raw material for bioelastomer synthesis

Karakterisasi Kondisi Penggumpalan Dan Mutu Karet Yang Digumpalkan Dengan Koagulan Deorub Formula Baru

Penggunaan koagulan menentukan kondisi penggumpalan dan mutu karet yang akan dihasilkan. Koagulan anjuran, asam format dan asap cair murni, masih belum digunakan secara luas oleh petani karet. Asam format menghasilkan bokar berbau busuk, berbahaya bagi manusia dan lingkungan serta harganya mahal. Sedangkan asap cair murni memerlukan konsentrasi dan dosis yang lebih banyak sehingga kurang ekonomis. Sekarang ini sudah dikembangkan koagulan Deorub formula baru yang memiliki kelebihan dibandingkan kedua koagulan anjuran tersebut. Tujuan penelitian ini adalah untuk mengetahui dan mempelajari karakteristik kondisi penggumpalan dan mutu karet yang digumpalkan dengan koagulan Deorub formula baru. Parameter yang diamati terdiri atas kondisi penggumpalan, kadar karet kering koagulum, karakteristik karet mentah, mutu teknis, karateristik vulkanisasi, dan sifat fisik vulkanisat karet yang dihasilkan. Hasil penelitian menunjukkan bahwa waktu, pH penggumpalan, mutu teknis, modulus torsi, dan sifat fisik vulkanisat karet yang digumpalkan dengan koagulan Deorub formula baru tidak berbeda dibandingkan asam format dan lebih baik dari Deorub K. Koagulum yang digumpalkan dengan Deorub formula baru ini mempunyai warna coklat muda dan bau asap ringan dengan kadar karet kering lebih tinggi. Mutu teknis karet dari kedua koagulan juga tidak berbeda nyata. Diterima : 15 April 2015; Direvisi : 30 Juni 2015; Disetujui : 3 Agustus 2015 How to Cite : Vachlepi, A., Suwardin, D., & Purbaya, M. (2015). Karakterisasi kondisi penggumpalan dan mutu karet yang digumpalkan dengan koagulan deorub formula baru. Jurnal Penelitian Karet, 33(2), 175-182. Retrieved from http://ejournal.puslitkaret.co.id/index.php/jpk/article/view/18

Family of neural wiring receptors in bilaterians defined by phylogenetic, biochemical, and structural evidence

The evolution of complex nervous systems was accompanied by the expansion of numerous protein families, including cell-adhesion molecules, surface receptors, and their ligands. These proteins mediate axonal guidance, synapse targeting, and other neuronal wiring-related functions. Recently, 32 interacting cell surface proteins belonging to two newly defined families of the Ig superfamily (IgSF) in fruit flies were discovered to label different subsets of neurons in the brain and ventral nerve cord. They have been shown to be involved in synaptic targeting and morphogenesis, retrograde signaling, and neuronal survival. Here, we show that these proteins, Dprs and DIPs, are members of a widely distributed family of two- and three-Ig domain molecules with neuronal wiring functions, which we refer to as Wirins. Beginning from a single ancestral Wirin gene in the last common ancestor of Bilateria, numerous gene duplications produced the heterophilic Dprs and DIPs in protostomes, along with two other subfamilies that diversified independently across protostome phyla. In deuterostomes, the ancestral Wirin evolved into the IgLON subfamily of neuronal receptors. We show that IgLONs interact with each other and that their complexes can be broken by mutations designed using homology models based on Dpr and DIP structures. The nematode orthologs ZIG-8 and RIG-5 also form heterophilic and homophilic complexes, and crystal structures reveal numerous apparently ancestral features shared with Dpr-DIP complexes. The evolutionary, biochemical, and structural relationships we demonstrate here provide insights into neural development and the rise of the metazoan nervous system

A comparative study to see the effectiveness of Pap smear, visual inspection with 3-5% acetic acid and its confirmation by cervical biopsy

Background: Cancer of the cervix is a leading cause of morbidity and mortality among women worldwide. The present study was undertaken to compare the effectiveness of Pap smear and visual inspection with 3-5% acetic acid (VIA) in screening carcinoma cervix followed by its confirmation by cervical biopsy.Methods: A total of 100 patients with abnormal looking cervices or symptomatic patients having age beyond 30 years, attending the obstetrics and gynaecology OPD at Naval Hospital Powai, Mumbai from 31st December 2015 to 31st December 2017 were selected for the study. Pap smear and VIA was done on consecutive days. In positive cases cervical biopsy were done to confirm the result.Results: The sensitivity of VIA was 100% but at the same time specificity was 41% there will be unnecessary investigation and biopsy in false positive cases. The sensitivity of cytology was 75% and specificity was 97%. Not a single case was missed by Pap smear only one case of severe dysplasia on cytology had squamous cell carcinoma on HPE which was done after 90 days because of delay in patients follow up.Conclusions: Both the Pap smears and VIA is very effective screening tool for cervical cancer and histopathological examination remains the mainstay. But VIA is very cost effective and easy procedure, though it gives false positive reports but is not going to miss any case, rather leads to over diagnosis of the cases with cervicitis and hence treatment starts early and thus the progress of disease can be slowed down or even stopped

Simulation for training in sinus floor elevation : new surgical bench model

Objectives: to describe a bench model (workshop of abilities) for sinus floor elevation (SFE) training that simulates the surgical environment and to assess its effectiveness in terms of trainees? perception. Study design: thirty-six randomly selected postgraduate students entered this cross-sectional pilot study and asked to fill in an anonymous, self-applied, 12-item questionnaire about a SFE workshop that included a study guide containing the workshop?s details, supervised practice on a simulated surgical environment, and assessment by means of specific check-lists. Results: Thirtiy-six fresh sheep heads were prepared to allow access to the buccal vestible. Using the facial tuber, third premolar and a 3D-CT study as landmarks for trepanation, the sinus membrane was lifted, the space filled with ceramic material and closed with a resorbable membrane. The participants agreed on their ability to perform SFE in a simulated situation (median score= 4.5; range 2-5) and felt capable to teach the technique to other clinicians or to undertake the procedure for a patient under supervision of an expert surgeon (median= 4; range 1-5 ). There were no differences on their perceived ability to undertake the technique on a model or on a real patient under supervision of an expert surgeon (p=0.36). Conclusions: Clinical abilities workshops for SFE teaching are an essential educational tool but supervised clinical practice should always precede autonomous SFE on real patients. Simulation procedures (workshop of abilities) are perceived by the partakers as useful for the surgical practice. However, more studies are needed to validate the procedure and to address cognitive and communication skills, that are clearly integral parts of surgical performance

Recognition process of jamming signals superimposed on GSM-R radiocommunications

This paper explores an approach trying to recognize the presence of electromagnetic attacks on an equipment. Wireless communications are widely used in railway traffic management systems. Such systems are probably susceptible to be disturbed by malicious actions involving jammers. The general objective of this work is to develop a specific method enabling to detect and to recognize these types of interfering signals. This method could be used to involve adequate reactions in order to reduce the impact on the railway network. This paper focuses on the recognition method. It is based on accurate statistical models of signals generated by jammers. This work is carried out in the framework of the European project “SECRET” for SECurity of Railways against Electromagnetic aTtacks

Which Green Matters for Whom? Greening and Firm Performance across Age and Size Distribution of Firms.

A growing body of literature links firm performance with sustainability efforts.We contribute to this literature by developing a novel framework for contextualising greening through the lens of tangibility and visibility of greening activities and examine the impact of different types of greening on firm performance along the age and size distribution of firms. The empirical results based on a large-scale database suggest that rewards to different types of greening differ across age and size distributions

Bulbar and speech motor assessment in ALS: Challenges and future directions

Bulbar motor deterioration due to amyotrophic lateral sclerosis (ALS) leads to the eventual impairment of speech and swallowing functions. Despite these devastating consequences, no standardized diagnostic procedure for assessing bulbar dysfunction in ALS exists and adequate objective markers of bulbar deterioration have not been identifi ed. In this paper, we consider objective measures of speech motor function, which show promise for forming the basis of a comprehensive, quantitative bulbar motor assessment in ALS. These measures are based on the assessment of four speech subsystems: respiratory, phonatory, articulatory, and resonatory. The goal of this research is to design a non-invasive, comprehensive bulbar motor assessment instrument intended for early detection, monitoring of disease progression, and clinical trial application. Preliminary data from an ongoing study of bulbar motor decline are presented, which demonstrate the potential clinical effi cacy of the speech subsystem approach