An example of spectral phase transition phenomenon in a class of Jacobi matrices with periodically modulated weights

We consider self-adjoint unbounded Jacobi matrices with diagonal q_n=n and weights \lambda_n=c_n n, where c_n is a 2-periodical sequence of real numbers. The parameter space is decomposed into several separate regions, where the spectrum is either purely absolutely continuous or discrete. This constitutes an example of the spectral phase transition of the first order. We study the lines where the spectral phase transition occurs, obtaining the following main result: either the interval (-\infty;1/2) or the interval (1/2;+\infty) is covered by the absolutely continuous spectrum, the remainder of the spectrum being pure point. The proof is based on finding asymptotics of generalized eigenvectors via the Birkhoff-Adams Theorem. We also consider the degenerate case, which constitutes yet another example of the spectral phase transition

Change of support correction in mineral resource estimation

The success of any mining operation greatly, if not entirely, depends on the accuracy of prediction of recoverable mining reserves. However, prior to mining, knowledge about the distribution of the Selective Mining Unit (SMU) is limited. The SMU represents the volume on which extraction of ore takes place and on which recoverable mining reserves are based. Realistic recoverable reserve estimates can be obtained from the grade-tonnage curve that corresponds to the unknown distribution of the SMU rather than to the distribution of exploration sample data. In general, if the reserve calculation, at the given cut-off grade, is based upon exploration drill samples, with much smaller support than the SMU, then there is a high probability of incorrect estimation of the tonnage and the grade of ore, and this can have serious implications for the economic side of the mining project. Various techniques for correction for the change of support of data, in other words change of the volume on which the data are defined, enable more accurate estimates of the distribution of the variable of interest (that is grade of a precious metal). The fact that the volume (support) represented by the variable is taken into account makes the estimates more reliable and, as we will show in the study, closer to reality. The distribution of the SMU is derived from the known distribution of samples by applying a correction model. Among these techniques arc two recent methods these arc a conditional simulation method detailed by I. Glacken and a kriging method due to A. Arik. This study aims to examine these two methods and compare them with the standard techniques. The methods will be applied to real data acquired from the Boddington Gold Mine in the south-west of Western Australia. In addition to accuracy, the practicality and simplicity of implementation of each method will also be discussed

Infeksi Nosokomial Saluran Nafas Bawah (Insnb) di Rumah Sakit Khusus Penyakit Menular, Jakarta

A prospective study to determine the incidence of lower respiratory tract nosocomial infection (LRNI) was conducted at the Infectious Diseases Hospital of Jakarta (IDH) in 1982-1983 for one year duration. Samples were taken randomly from 2 group of hospitalized patients: diarrheal and febrile patients. The criteria for development of lower respiratory infection were based on history, physical examination and chest x-ray examination, which was done only Li some of the patients those with duration of hospitalization >2 days. From 2288 patients hospitalized during that period,723 (31.6%) patients fulfilled the criteria to be included in the nosocomial study, and from this group 34 (4.7%) of them met the criteria for LRNI. The LRNI was observed in almost similar percentage in both sexes of patients (4.5% in males and 4.9% in females). Comparison of different age group of patients showed that 5-11 years old children had highest rate of LRNI (14,5%) and significantly (p<0,01) compare to > 12 years old followed by children 1-4 year old (7,1%), while children <1 year had 5.9%, and the lowest rate was in > 12 years group with 2.7% Febrile patients had significantly higher rate of LRNI compared to diarrhea patients (11.6% vs 1.1%; p< 0,001). Patients who received oxygen and bronchial mucus suction had significantly higher rate of LRNI (27.4%) vs 3.1%; p<0,001) compared to those who did not (3,1%, p< 0,001). Average duration of hospitalization for patients with LRNI was longer than for patients without it (11.1 vs 5.1 days). Case fatality rate in patients with LRNI was also higher 17.7%, compared only 1.2% in patients without LRNI. Factors involved in CFR was mostly due to severity of underlying disease and respiratory failure due to pneumonia in patients who developed LRNI

Pencemaran Kuman di Lingkungan Rumah Sakit Khusus Penyakit Menular, Jakarta

A survey to establish environmental contamination was conducted at the Infectious Diseases Hospital (IDH) of Jakarta by taking swabs from 90 hospital personnels who are directly involved in patients care. These swabs were taken from their hands, nails, throat and rectum. Swabs and cultures were also obtained from 167 equipments, solid and liquid material, food from the hospital, and the air in the hospital wards. From total of 437 specimen obtained, 73.7% showed presence contaminated result. There was 100% positive culture result noted in hands and nails swabs, 94.8% culture positive for any microorganism result was obtained from throat swabs while rectal swab indicated only 4.4% rate of contamination. Results of 167 swabs from material/equipments in the hospital, showed that 85.1% of them were not sterile, this included 59.1% of 54 liquid material, 37.3% from 35 liquid material which were supposed to be sterile, 100% positive culture of 17 liquid material specimen that were supposed to be clean. From solid materials 66.7% of 51 specimen were not sterile. This included 76.2% from 21 specimen that were supposed to be sterile, and 100% from 7 specimen that supposed to be clean. Also 100% non sterility was obtained from 23 other material and 62 equipment. Recovered bacterias consisted of both gram positive and negative bacterias and almost all of them represented normal human flora. Some of them potentially could became pathogen including pathogen for nosocomial infection. From the hospital personnels hand swabs, 25.4% were spore-forming bacteria and from the throat swabs 46.7% yielded Streptococcus ~ hemolyticus, and 4.4% were positive for coliform bacteria from rectal swabs. Results of material and equipment showed majority of aerobic rods (31.5%). Some of the bacteria recovered, including Pseudomonas aeruginosa and Enterobacter aerogenes were resistant to commonly used antibiotics in the hospital (Ampicillin, Tetracycline and Chloramphenicol)

Pencemaran Jarum Infus Intervena (IV) di Rumah Sakit Khusus Penyakit Menular, Jakarta

A prospective survey to evaluate rate of intravenous needle contamination was conducted at Infectious Diseases Hospital of Jakarta among patients whom received intravenous (i.v.) fluid or transfusion during 1 year period in 1982-1983. The survey was conducted through random culture of the distal part of the intravenous needle placed in the patients vein after completion of intravenous treatment. The exact time for the needle placement and extraction, local and systemic reactions observed in patients, were all recorded. From 559 culture of the i.v. needles which fulfilled the survey criteria, 238 were positive, indicating 42.3% contamination rate of the i.v. needles. The rate was higher in febrile patients (47.2%) compared to diarrhea patients (41.5%) Average duration of infusion (the duration of time the needle stayed in the vein) was 38.9 hours, with average of 15.8 hours in diarrhea patients and 104,6 hours in febrile patients. Mean duration of time for local reaction development was 36.8 hours, with 24.3 hours in diarrhea patients and 65.9 hours in febrile patients. Patients with positive culture had higher rate of local reaction (17.6% vs 13.4%), systemic reaction (18.4% vs 11.8%), nosokomial bacteremia (88% vs 4,4%) and community acquired infection (5.9% vs 3.7%) compared to patients with negative cultures. For patients with longer than 48 hours infusion, 58.5% had positive culture from i.v. needles, 21.9% had local reaction, 40.2% had systemic reaction which all were higher compared to patients who had less than 48 hour infusion with p<0.001, p<0.02 and p<0.001 respectively. Isolated bacteria from i.v. needles were 74.6% gram positive bacterias and 25.4% gram negative, with Staphylococcus epidermidis (38%) as the leading positive culture. Isolated bacteria had high rate of resistancy \u27oward commonly used antibiotics in the hospital

Infeksi Nosokomial Saluran Kencing (Insk) di Rumah Sakit Khusus Penyakit Menular, Jakarta

A prospective survey to establish the incidence of urinary tract nosocomial infection (UTNI) was conducted at the Infectious Diseases Hospital of Jakarta for one year duration in 1982-1983. The study was done by taking random samples from patients hospitalized for longer than 2 days through urine cultures on day 1, 3 and 7 and other necessary examination. From 2288 patients hospitalized during that period, 723 patients (aged 2 months-70 years) met the requirement to be included in the study, and 115 (15.9%) of them met the criteria for UTNI. Female patients had higher rate of UTNI compared to male patients (19.8% vs 12.4%). The age group with highest rate of UTNI was children with < 1 year of age and the rate of UTNI decreased as the age of patients increased. Febrile patients had significantly higher rate of UTNI compared to diarrhea patients (33.4% vs 2,4%, p < 0.001). Patients who had catheterization had significantly higher rate of UTNI compared to patients without catheter placement (85.7% vs 12.3% p <0.05). Antibiotics treatment prior to hospitalization was associated with higher rate of UTNI compared to patients without it (22.8% vs 12.6% p < 0.01) as it was also observed with hospitalization for 7 days or longer (15.8% vs 11.9%) of it is compared to shorter duration of hospitalization. Gram negative bacterias were the most commonly recovered from the urine cultures compared to gram positive (89.8% vs 10.2%) with E. coli (24.2%) as the leading organism. Other recovered organism, Proteus spp and Citrobacter bacilli showed high resistancy toward antibiotics commonly used in the hospital. Average duration of hospitalization for patients with UTNI (9.6 days) was longer compared to average duration for patients without UTNI (4.4 days). Six out of 115 patients with UTNI died (5.2%) compared to only 1.3% mortality in patients without UTNI. No single factor was significantly shown to be responsible for higher mortality rate of patients with UTNI, possibly was due to more severe condition of underlying disease of patients with UTNI

Infeksi Komunitas (Ik)/infeksi Luar Rumah Sakit (Ilrs) (Community Acquired Infection) di Rumah Sakit Khusus Penyakit Menular, Jakarta

A one year prospective study was conducted at the Infectious Diseases Hospital (IDH) of Jakarta in 1982-1983 to survey the rate of community acquired infection (CAI). Blood culture, rectal swab, urine culture and in some patients cerebro spinal fluid culture were obtained randomly from hospitalized patient at the time of admission. From 723 patients with age 2 months-70 years, who were examined and fulfilled the study criteria, 504 (69,7%) patients were positive for CAI resulted in total of 611 CAIs. Based on anatomical location, this number consists of 53.5% CAI of GI Tract, 20.9% CAI of Urinary Tract, 9.5% CAI bacteremia and 0.6% CAI involving central nervous system. Incidence rate was significantly higher in female (74.1%) compared to male (65.7%) (p12 years patients (73.9%) compared to children <12 years (p<0,01). Diarrhea patients had significantly higher CAI (77.4%) compared to febrile patients (55.2%) (p<0,01). Patients who had not received antibiotic prior to admission had higher rate of CAI (70.9%) compared to who received it prior to admission (67.1%) Etiologic agents most commonly recovered were gram negative bacterias (94.9%) with Vibrio cholerae (48.6%) as the leading cause, and only 5.1% were gram positive. Some of bacteria found as the etiologic agent of CAI, were Salmonella group D, Salmonella group E4, Proteus vulgaris and ruttgerii, Klebsiella pneumoniae, Mima polymorpha, Alkaligenes sp showed high rate of resistancy to commonly used antibiotics. (Ampicillin, Tetracycline, Chloramphenicol and Trimethoprim + Sulfamethoxazole). Average duration of hospitalization for CAI cases (6,4 days) was longer than in cases without CAI (4,3 days). There were 11 deaths (2.2%) in cases with CAI and 2 deaths (1.4%) in patients without CAI, with death rate was higher in males (2.4%) compared to female (1.9%), and highest was in less than 1 year old age group patient (13.6%), also significantly higher in febrile patients compared to diarrhea patients (7.2% vs 0.3%, p< 0.001). The higher mortality rate in CAI is due to more severe condition of underlying disease of patients who had CAI

Spatio-temporal image correlation (STIC) in evaluation of advanced neuroendocrine tumours

Introduction: 4D Ultrasound technology merging the Power Doppler option called High-Definition Flow (HDF) with Spatio-Temporal Image Correlation (STIC) is used in gynaecology and obstetrics. It seems to be a promising tool in assessing tissue vascularisation. The aim of the paper was to assess whether HDF STIC technique could be a useful tool for the evaluation of gastro-entero-pancreatic neuroendocrine neoplasm (GEP-NEN) advancement. Material and methods: Forty-eight patients [mean age 57.7 ± 10.3 years; male 40.9% (n = 18)] diagnosed with metastatic GEP-NENs were included in the analysis. All subjects were enrolled in the Department of Endocrinology and Neuroendocrine Tumours, Medical University of Silesia, Katowice. We analysed liver metastases. Patients with G3 grading or faintly vascularised lesions were excluded. HDF STIC volumes were acquired during USG examination. 4D indices [volumetric pulsatility index (vPI) and volumetric systolic/diastolic index (vS/D)] were calculated using dedicated software. Results: There were no correlations between vS/D and Ki-67 [p = 0.67; r = –0.19; (–0.28–0.19)], CgA [p = 0.47; r = –0.11; (–0.38–0,19)], 5-HIAA [p = 0.52; r = –0.09 (–0.37–0.2)], serotonin [p = 0.83; r = –0.03 (–0.32–0.26)], and VCAM-1 (p = 0.62; r = 0.09 (–03–0.47)]. The were no correlations between vPI and Ki-67 [p = 0.29; r = –0.16 (–0.45–0.14)], CgA (p = 0.46; r = –0.11 (–0.39–0.19)], 5-HIAA [p = 0.52; r = –0.09 (–0.37–0.2)], serotonin [p = 0.82; r = –0.03 (–0.32–0.26)], and VCAM-1 (p = 0.62; r = –0.09 (–03–0.47)]. There was no significant difference between carcinoid versus non-carcinoid patients if compared by vS/D and vPI (p = 0.62, p = 0.61, respectively). Conclusions: HDF STIC seems not to be an efficient marker to assess advancement of NENs, due to lack of correlation with widely used and approved markers of progression.

High-precision measurement of the half-life of 62^{62}Ga

The beta-decay half-life of 62Ga has been studied with high precision using on-line mass separated samples. The decay of 62Ga which is dominated by a 0+ to 0+ transition to the ground state of 62Zn yields a half-life of T_{1/2} = 116.19(4) ms. This result is more precise than any previous measurement by about a factor of four or more. The present value is in agreement with older literature values, but slightly disagrees with a recent measurement. We determine an error weighted average value of all experimental half-lives of 116.18(4) ms.Comment: 9 pages, 5 figures, accepted for publication in PR