scholarly journals PENGARUH RADIASI SINAR ULTRAVIOLET TIPE C (UVC) TERHADAP KULTUR TOTAL MIKROBA IKAN ASAP PINEKUHE

2020 ◽  
Vol 6 (2) ◽  
pp. 42-45
Author(s):  
Jaka Frianto Putra Palawe ◽  
Jefri Mandeno

Untuk meningkatkan mutu produk olahan khas daerah, khususnya ikan asap pinekuhe, pengembangan teknik atau instrumen baru menjadi sebuah keharusan. Sejauh ini, metode yang umum digunakan untuk mempertahankan mutu produk pangan, khususnya mutu mikrobiologis, adalah mensterilkan produk pangan untuk mengurangi dan menginaktifkan mikroba kontaminan misalnya melalui perebusan, penggaraman atau pengasapan. Tetapi metode steriliasi menggunakan sinar ultraviolet khususnya tipe C (UVC) belum banyak diterapkan pada produk pangan di Indonesia. Sinar ultraviolet adalah gelombang elektromagnetik yang memiliki muatan elektron berfrekuensi tinggi dan panjang gelombang 100-400 nm. Sinar UV dapat memotong rantai basa nitrogen dalam RNA atau DNA sehingga menyebabkan kegagalan pemberian kode genetik untuk sintesa protein dan kematian mikroba. Penelitian ini bertujuan untuk mempelajari pengaruh sinar UVC terhadap isolat kultur mikroba dari ikan asap pinekuhe dengan menggunakan metode observasi dan analisa data secara deskriptif. Koloni bakteri yang diisolasi dari ikan pinekuhe dipaparkan dengan sinar UVC dengan perlakuan (12, 24, 36 dan 48) jam. Hasil penelitian menunjukan bahwa sinar ultra violet tipe c (UVC) dengan daya 8 va dan penyinaran 48 jam mempengaruhi pertumbuhan koloni mikroba ikan asap pinekuhe secara maksimal berupa kekeringan pada koloni bakteri isolat dari ikan asap pinekuhe.   To improve quality of pinekuhe smoked fish locally produced in Sangihe Islands, development of new techniques or instruments becomes necessary. Widely used techniques for maintaining food quality mainly include sterilization through boiling, salting or smoking. To date, however, sterilization by ultraviolet type C (UVC) has been poorly practiced for preserving food products in Indonesia. Ultraviolet light is an electromagnetic wave that has a high frequency electron charge with a wavelength of 100-400 nm. It can cut the nitrogenous base chains in RNA or DNA resulting in coding failure in protein synthesis, causing the death of microbes. This research aimed to study the effect of UVC on microbes isolated from pinekuhe. The results showed that UVC radiation with 8 va for 48 hours significantly affected the growth of microbial colonies isolated from the smoked fish, drying up the bacterial colony.

2019 ◽  
Vol 245 (12) ◽  
pp. 2715-2725 ◽  
Author(s):  
Tomasz Cebulak ◽  
Jan Oszmiański ◽  
Ireneusz Kapusta ◽  
Sabina Lachowicz

Abstract Growing social interest in foods with high biological quality results in the need to look for possibilities of increasing the biological quality of food products. The aim of this research was an attempt to estimate the increase of polyphenolic compounds (by UPLC-PDA-MS/MS) in the flesh and skin of pear under the influence of stress elicitors such as UVC radiation, L-EMF, H-EMF and US with various exposure times. The applied stress factors differentiated the content of phenolic acids, flavan-3-ols and flavonols both in flesh and in skin. In all cases, pear skin demonstrated a decrease in the sum of polyphenolic compounds; however, when it comes to flavan-3-ols and procyanidins, the concentration of the compounds increased in two cases: after a 30-min exposure to L-EMF (+ 18%) and after a 5-min exposure to H-EMF (+ 20%). Following a 30-min flesh exposure to US, the determined sum of polyphenolic compounds was + 28% higher than in the control sample. It was observed that the level of flavan-3-ols and procyanidins in the flesh increased after a 60-min exposure to UVC radiation and low-frequency and high-frequency electromagnetic fields, and after a 20-min and 30-min exposure to ultrasounds. The presence of flavonols was only observed in pear skin. The research results show that it is possible to produce juice with a higher content of polyphenolic compounds, because juice is obtained mainly from the flesh; however, there is a need for further research to confirm the observed tendencies in the changes of polyphenolic compounds in fractions of pears.


Author(s):  
S. R. Rakhmanov

In some cases, the processes of piercing or expanding pipe blanks involve the use of high-frequency active vibrations. However, due to insufficient knowledge, these processes are not widely used in the practice of seamless pipes production. In particular, the problems of increasing the efficiency of the processes of piercing or expanding a pipe blank at a piercing press using high-frequency vibrations are being solved without proper research and, as a rule, by experiments. The elaboration of modern technological processes for the production of seamless pipes using high-frequency vibrations is directly related to the choice of rational modes of metal deformation and the prediction resistance indicators of technological tools and the reliability of equipment operation. The creation of a mathematical model of the process of vibrating piercing (expansion) of an axisymmetric pipe blank at a piercing press of a pipe press facility is an actual task. A calculation scheme for the process of piercing a pipe plank has been elaborated. A dependence was obtained characterizing the speed of front of plastic deformation propagation on the speed of penetration of a vibrated axisymmetric mandrel into the pipe workpiece being pierced. The dynamic characteristics of the occurrence of wave phenomena in the metal being pierced under the influence of a vibrated tool have been determined, which significantly complements the previously known ideas about the stress-strain state of the metal in the deformation zone. The deformation fields in the zones of the disturbed region of the deformation zone were established, taking into account the high-frequency vibrations of the technological tool. It has been established that the choice of rational parameters (amplitude-frequency characteristics) of the vibration piercing process of a pipe blank results in significant increase in the efficiency of the process, the durability of the technological tool and the quality of the pierced blanks.


1998 ◽  
Vol 2 ◽  
pp. 115-122
Author(s):  
Donatas Švitra ◽  
Jolanta Janutėnienė

In the practice of processing of metals by cutting it is necessary to overcome the vibration of the cutting tool, the processed detail and units of the machine tool. These vibrations in many cases are an obstacle to increase the productivity and quality of treatment of details on metal-cutting machine tools. Vibration at cutting of metals is a very diverse phenomenon due to both it’s nature and the form of oscillatory motion. The most general classification of vibrations at cutting is a division them into forced vibration and autovibrations. The most difficult to remove and poorly investigated are the autovibrations, i.e. vibrations arising at the absence of external periodic forces. The autovibrations, stipulated by the process of cutting on metalcutting machine are of two types: the low-frequency autovibrations and high-frequency autovibrations. When the low-frequency autovibration there appear, the cutting process ought to be terminated and the cause of the vibrations eliminated. Otherwise, there is a danger of a break of both machine and tool. In the case of high-frequency vibration the machine operates apparently quiently, but the processed surface feature small-sized roughness. The frequency of autovibrations can reach 5000 Hz and more.


2020 ◽  
Vol 16 (35) ◽  
pp. 2997-3013
Author(s):  
Kentaro Kogushi ◽  
Michael LoPresti ◽  
Shunya Ikeda

Background: Synovial sarcoma (SS) is a rare, aggressive soft tissue sarcoma with a poor prognosis after metastasis. The objective of this study was to conduct a systematic review of the clinical evidence for therapeutic options for adults with metastatic or advanced SS. Materials & methods: Relevant databases were searched with predefined keywords. Results: Thirty-nine publications reported clinical data for systemic treatment and other interventions. Data on survival outcomes varied but were generally poor (progression-free survival: 1.0–7.7 months; overall survival: 6.7–29.2 months) for adults with metastatic and advanced SS. A high frequency of neutropenia with systemic treatment and low quality of life post-progression were reported. Conclusion: Reported evidence suggests poor outcomes in adults with metastatic and advanced SS and the need for the development of new treatment modalities.


Horticulturae ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 80
Author(s):  
Triston Hooks ◽  
Joseph Masabni ◽  
Ling Sun ◽  
Genhua Niu

Blue light and ultra-violet (UV) light have been shown to influence plant growth, morphology, and quality. In this study, we investigated the effects of pre-harvest supplemental lighting using UV-A and blue (UV-A/Blue) light and red and blue (RB) light on growth and nutritional quality of lettuce grown hydroponically in two greenhouse experiments. The RB spectrum was applied pre-harvest for two days or nights, while the UV-A/Blue spectrum was applied pre-harvest for two or four days or nights. All pre-harvest supplemental lighting treatments had a same duration of 12 h with a photon flux density (PFD) of 171 μmol m−2 s−1. Results of both experiments showed that pre-harvest supplemental lighting using UV A/Blue or RB light can increase the growth and nutritional quality of lettuce grown hydroponically. The enhancement of lettuce growth and nutritional quality by the pre-harvest supplemental lighting was more effective under low daily light integral (DLI) compared to a high DLI and tended to be more effective when applied during the night, regardless of spectrum.


2021 ◽  
Vol 9 (5) ◽  
pp. 465
Author(s):  
Angelos Ikonomakis ◽  
Ulrik Dam Nielsen ◽  
Klaus Kähler Holst ◽  
Jesper Dietz ◽  
Roberto Galeazzi

This paper examines the statistical properties and the quality of the speed through water (STW) measurement based on data extracted from almost 200 container ships of Maersk Line’s fleet for 3 years of operation. The analysis uses high-frequency sensor data along with additional data sources derived from external providers. The interest of the study has its background in the accuracy of STW measurement as the most important parameter in the assessment of a ship’s performance analysis. The paper contains a thorough analysis of the measurements assumed to be related with the STW error, along with a descriptive decomposition of the main variables by sea region including sea state, vessel class, vessel IMO number and manufacturer of the speed-log installed in each ship. The paper suggests a semi-empirical method using a threshold to identify potential error in a ship’s STW measurement. The study revealed that the sea region is the most influential factor for the STW accuracy and that 26% of the ships of the dataset’s fleet warrant further investigation.


1989 ◽  
Vol 4 (2) ◽  
pp. 117-122 ◽  
Author(s):  
J.-F. Dreyfus ◽  
D. Cremniter ◽  
J.D. Guelfi

SummaryWe are still confronted by numerous different nosographic models and problems concerning the objective evaluation of patients progress during treatment. It is interesting to consider the consequences of this situation in psychiatry which still involves a relative diversity of practical methods used in clinical trials. The recommendations of the USA Food and Drug Administration, on the one hand, constitute a highly structured and precise reference. The World Health Organization, on the other hand, promulgates general recommendations resulting from a compromise designed to satisfy the greatest number of clinicians.Despite the apparently diverse principles and the different practical methods they propose, both those sets of recommendations have been useful in inspiring clinicians to reflect upon these different methodological approaches. The qualities of the inclusion criteria used in the study of patients and the sensitivity of the different measuring instruments have allowed psychotropic drug users as well as producers to recognize the need for a certain rigour in clinical trials.The FDA and WHO guidelines have certainly improved the quality of clinical trials in psychopharmacology. However, they also represent a source of resistance to innovation.A series of consensus meetings to first reconcile US and European points of view and later to include new techniques in the recognized sets of methods would therefore be helpful.


2020 ◽  
Vol 12 (2) ◽  
pp. 387-398
Author(s):  
Sylvia O. OGOANAH ◽  
Uzoamaka N. NGWOKE ◽  
Edokpolor O. OHANMU ◽  
Pascal C. OKOYE ◽  
Beckley IKHAJIAGBE

The study investigated the enhancement of soil quality of an oil-polluted ultisol using livestock wastes. Top soil (0 - 10 cm) was obtained as a pooled sample and polluted with spent lubricating oil at 10% w/w. The soil was subsequently amended with sun-dried goat (GT), rabbit (RB), and poultry (PG) dung at 10% w/w on dry weight basis both in singles, double-mixed, and triple-mixed combinations. Twelve weeks after treatment application, results showed that there was a 93.9% decrease (p<0.05) in bacterial colony count in the oil-polluted soil compared to the control. Penicillium notatum and Aspergillus niger as well as Bacillus sp. and Proteus sp. were the prominent fungal and bacterial species identified respectively. The most abundant plant in the soil seed bank was Panicum maximum with 10.4% abundance and this showed possible involvement of the plant in remediation of oil-pollution. The total hydrocarbon content of the oil-polluted soil was 9984.0 mg/kg, compared to 3170.6 mg/kg when amended with RB+GT, implying 76.77% remediation efficiency. Among several trials employed in this study, the combination of rabbit and goat wastes proved to be more effective in reducing the total hydrocarbon content of oil-polluted soil and therefore, is recommended as a potential candidate for application in the bioremediation of such soil.


1961 ◽  
Vol 2 (2) ◽  
pp. 204-230 ◽  
Author(s):  
Robin Holliday

1. Many of the Ustilaginales, or smut fungi, appear to have the qualities necessary for the application of modern techniques of microbial genetics.Ustilago maydisis considered the most suitable species.2. Investigations of the mating system confirm reports that the production of diploid brandspores in the host is controlled by alleles at two loci.3. Genetic markers were obtained by inducing mutations in a wild-type strain with ultra-violet light. Of 100 biochemical mutants which were isolated, the growth requirements of 94 were identified. Thirty of these were used in genetic tests.4. The compact growth of colonies on artificial media allowed new techniques to be developed by means of which large samples of progeny could be isolated and identified easily. The analysis of brandspore colonies consisting of the products of single meiotic divisions is the quickest method for detecting linkage, but its accurate measurement appears to be achieved by examining the individual members of tetrads.5. Linkage was detected relatively rarely, but eight markers, including theamating-type locus, were assigned to one or other of two linkage groups. Although recombination values were not always determined accurately owing to irregular basidiospore germination, the auxotrophic markers in each group could be mapped in a linear order. Since no indication of other linkage groups was obtained, the genetic evidence is so far consistent with cytological reports that the basic haploid chromosome number is two in the smut fungi.6. Three linked markers were used to investigate chromatid interference by tetrad analysis. None was detected in a total of eighteen double exchanges.


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