Influence of Intracavity Power on Frequency Characteristics of Iodine-Stabilized He-Ne Laser

Following a shift in the industry to solid-state lasers during the past decade, resonator tubes which can be used in iodine-stabilized helium-neon (He-Ne) lasers are being discontinued by most manufacturers. After installing a replacement tube, it was discovered that its intracavity power was not equal to that of the original tube. The influence of this change on the uncertainty of frequency was determined over the course of several months. Mirrors in the optical cavity were adjusted for optimal intracavity power using short heterodyne beat frequency measurements with a reference laser. Data for stability and absolute value of the reference frequency were well-known and provided in advance by calibration with the comb method. The sensitivity coefficient of the output beam power was estimated from beat frequency deviations measured at several values of power inside the range of the stabile operation of the laser. Finally, a long-term measurement of beat frequency provided data about the stability and frequency offset

Razvoj sustava za interferencijsko umjeravanje etalona duljine metodom faznih pomaka

Prijenos valne duljine primarnog etalona na fizičke etalone predstavlja najvišu razinu u osiguravanju sljedivosti mjerenja duljine; osnovni je cilj ovog rada tu najvišu razinu u osiguravanju sljedivosti ostvariti u \Nacionalnom laboratoriju za duljinu. U radu su predstavljene modifikacije postojećeg interferometra kojima je omogućeno korištenje laserskih izvora svjetla, te dodatne modifikacije kojima su poboljšane mjeriteljske karakteristike i smanjena nesigurnost interferencijskog umjeravanja etalona duljine primjenom postojećeg interferometra. Pri tome je implementirana i metoda faznih pomaka čime je ostvarena rezolucija mjernog sustava ispod jednog nanometra, a mogućnosti unaprijeđenog interferometra potvrđene su međunarodnom usporedbom. Po završetku ove faze istraživanja pokrenut je projekt izrade novog interferometra, kojim se željelo omogućiti dodatna istraživanja. Izrađen je Twyman-Green interferometar koji omogućuje kvalitetniju implementaciju metode faznih pomaka, kao i simultanu primjenu više valnih duljina, čime su izbjegnuti najizraženiji nedostaci do sada korištenog interferometra. Konačno, osmišljena je metoda za direktno mjerenje kontaktnog sloja, što do sada nije bilo moguće, te nova metoda za utvrđivanje fazne korekcije; obje su metode koncipirane tako da budu univerzalno primjenjive, bez obzira na specifičnu vrstu interferometra u kojem se koriste. U radu su prikazani izvodi i rezultati tih metoda, koji potvrđuju njihov doprinos u smanjenju mjerne nesigurnosti

The Impact of Football Training on Motor Development in Male Children

The aim of the study was to determine the effect of football school program and physical education curriculum on changes in the motor abilities of 7- and 8-year-old boys. The study included a sample of 180 boys divided into group 1 (7-year-old boys), subdivided to experimental (n=40) and control (n=50) groups, and group 2 (8-year-old boys), subdivided to experimental (n=40) and control (n=50) groups. Experimental groups included children attending three training units of football training over a 9-month period, in addition to the conventional physical education curriculum. Control groups included children attending only conventional physical education curriculum. All study subjects underwent testing with a battery of 12 motor tests at the beginning and at the end of the study. Results obtained by discriminative canonic analysis showed no statistically significant between-group difference in motor abilities at the beginning of the study. However, significant differences in favor of experimental groups were recorded at the end of the study. Favorable changes in all motor variables were observed in both experimental and control groups of children from the initial through the final state. These changes were more pronounced in experimental groups. Analysis of variance for difference variables (final to initial measurement) indicated programmed education in the form of football training in addition to regular physical education curriculum to predominantly influence the development of aerobic endurance, agility, speed and flexibility in 7-year-old boys, and of explosive strength, aerobic endurance, flexibility and speed in 8-year-old boys. In the latter, football training led to the formation of a motor complex integrating explosiveness, speed, coordination, endurance and flexibility as a general motor factor determining future quality development in football

Dabigatran Use Associated with Hemopericardium and Hemothorax

Concurrent spontaneous hemopericardium and hemothorax due to anticoagulant use are extremely rare in clinical practice. Dabigatran is an oral direct thrombin inhibitor approved to prevent stroke or thromboembolic episodes in patients with nonvalvular atrial fibrillation. We report the case of a 73-year-old man who received dabigatran therapy (150 mg twice a day) for 3 months and developed massive spontaneous hemothorax and hemopericardium associated with fever. Emergency chest computed tomography scan established higher-density pericardial effusion (22HU) and left pleural effusion of heterogeneous density (5–15 HU) which could be hemorrhagic content while the heart ultrasound finding confirmed pericardial effusion 7–9 mm thick, without affecting hemodynamics. Almost 1100 mL of blood was drained by ultrasoundguided thoracentesis. After excluding other possible causes, diagnostic withdrawal was performed for dabigatran and no further pleural or pericardium effusion developed after dabigatran was discontinued. Therefore, practitioners could be aware of hemothorax as well as hemopericardium as a potential complication of dabigatran therapy

Realization of the Highest Level of Traceability in Croatian National Laboratory for Length

Traceability of length measurement to the SI unit meter is realized by means of interferometry, and primary interferometers are used at the highest accuracy levels to perform calibration of national gauge block standards. These devices are expensive, given the fact that they are manufactured on order and used almost exclusively by national measurement institutes. Therefore, The Croatian Metrology Institute/Faculty of Mechanical Engineering and Naval Architecture – Laboratory for Precise Measurements of Length (HMI/FSB-LPMD) decided to retrofit and modify its Zeiss gauge block interferometer. Measurements presented in this paper demonstrate substantial improvements in accuracy and ease of use. These improvements established the highest level of traceability in the Laboratory and enabled it to publish appropriate calibration and measurement capabilities (CMC) value in the BIPM (Bureau International des Poids et Mesures) key comparison database (KCDB) under the Mutual Recognition Arrangement (MRA)

MENTAL HEALTH AND SELF-ESTEEM OF ACTIVE ATHLETES

Introduction: Systematic and continuous physical exercise of certain intensity and volume is irreplaceable in the stages of growth and development and in preventing impairments of the biological, functional and health state of the human organism.Many studies show that physical exercise contributes to development and reinforcement of mental health and increases self-esteem. Examine mental health and self-esteem of active athletes. Subjects and methods: The subjects of the study are active athletes from Herzegovina and students of the Faculty of Health Studies in Mostar. Mental health and self-esteem were measured by a sociodemographic questionnaire, The Symptom Checklist-90 and the Satisfaction With Life Scale. Results: There is a statistically significant difference in the frequency of exercise, active athletes have the highest percentage (100%) and state that they exercise often (almost every day) while university students have a significantly lower percentage (20%).Students scored significantly higher on the subscales for somatization, obsessive - compulsive symptoms, interpersonal vulnerability, depression, anxiety, aggression, phobia, and paranoia than active athletes. Active athletes have statistically higher scores for almost all the claims of the subjective assessment of life satisfaction. Conclusion: Active athletes showed significantly less psychological symptoms and better mental health, greater life satisfaction and higher self-esteem than students of the Faculty of Health Studies in Mostar

Milk yield and composition, body condition, rumen characteristics, and blood metabolites of dairy cows fed diet supplemented with palm oil

Background: An addition of rumen-protected fat to the diet of cows may limit negative energy balance and/or shorten its duration, leading to increased milk production with reduced risk of metabolic disorders in dairy cows. The aim of the study was to test the effect of rumen-inert fat supplement of palm oil on milk production, milk composition, rumen characteristics, and metabolic variables of early lactating dairy cows. For this purpose, 24 Holstein-Friesian cows were divided into two equal groups and fed a corn silage-based diet, without palm oil supplementation (control) or with 300 g palm oil (Palm Fat 99, Noack & Co. GmbH, Vienna, Austria) per cow for 8 weeks starting from day 30 after parturition. Milk, rumen, and blood samples were taken three times during experiment at days 30, 58, and 86 of lactation. Body condition scores of cows were determined in the same time periods. Milk yields were measured at the morning and evening milking (6(00) and 18(00)). Milk samples were analyzed for milk fat and milk protein content. Rumen content was tested for electrochemical reaction. A native slide was prepared for microscopical examination of the rumen protozoa motility that was numerically estimated. Protozoa were counted in whole rumen contents by light microscopy. Blood samples were tested for total protein, albumin, urea, tryglicerides, cholesterol, total bilirubin, beta-hydroxybutyrate, Ca, and P. Results: Compared with the control, palm oil supplementation resulted in an increase of the average milk yield and milk fat content. The loss in body condition was significantly lower in the group fed palm oil than in the control group. Rumen pH, total number, and motility of protozoa in the group fed palm oil were significantly higher than those in the control group. Palm oil supplementation did not influence blood metabolite concentrations except for urea and glucose which were significantly lower and Ca and cholesterol which were significantly higher in the palm oil-supplemented group. Conclusions: Our results indicate that supplementation with palm oil in weeks 4 to 12 postpartum spared postpartum body weight loss, increased milk yield and milk fat content, and had positive effects on rumen characteristics

Influence of fertilization on growth of Thuja occidentalis \u27Smaragd\u27

Danas je još uvijek, nažalost, analiza tla u rasadniku prije sadnje određene ukrasne vrste rijetkost. Isto tako nije uobičajeno da se preporuke za gnojidbu temelje na konkretnim rezultatima stanja hraniva u tlu. Stoga je u rasadniku postavljen pokus na vrsti Thuja occidentalis \u27Smaragd\u27, kako bi se korištenjem dvije razine kompleksnog mineralnog gnojiva (NPK 10-20-30) ispitao utjecaj gnojidbe na rast i razvoj biljaka, uspoređujući ih s negnojenom varijantom. Provedena istraživanja su pokazala da je gnojidba mineralnim gnojivom neovisno o količini utjecala je na porast visine biljaka tuje u odnosu na negnojenu varijantu. Gnojidba od 400 kg/ha NPK 10-20-30 utjecala je na porast visine biljaka za 20,8 cm u jednoj kalendarskoj godini, odnosno za razdoblje pokusa 38,62 cm. Gnojidba od 800 kg/ha NPK 10-20-30 utjecala je na porast visine biljaka za 21,51 cm u jednoj kalendarskoj godini, odnosno za razdoblje pokusa 40,73 cm. Na temelju kemijskih analiza tla utvrđeno je da u tlu nije došlo do značajnih promjena.Even today, the soil used in nursery gardens is still rarely analyzed prior to planting individual horticultural plants. It is not common either, to base fertilization recommendations on actual results of soil analyses. Therefore, an experiment was set up in the nursery garden using the species Thuja occidentalis ‘Smaragd’ (Arbor Vitae) with the objective to check the influence of fertilization to plants growth, comparing fertilized varieties with the non-fertilized one. During the experiment two varieties of a complex fertilizer (NPK 10-20-30) were used. Research results have shown that fertilization using fertilizers, disregarding the quantity used, improved the growth of Arbor Vitae plants in comparison with their non –fertilized variety. Use of 400 kg/ha of NPK 10-20-30 caused the plants to grow 20,8 cm during one calendar year, i.e. 38,62 cm during the experimentation period. Use of 800 kg/ha of NPK 10-20-30 caused the plants to grow 21,51 cm during one calendar year, i.e.40,73 cm during the experimentate period. Chemical analyses showed no significant changes in the soil