Praktičan primer povećanja energetske efikasnosti malih pumpnih stanica reprojektovanjem

The suction station "Gnjilan", belonging to the "Water-supply" Pirot municipal enterprise, has been used as an example of small pump stations energy efficiency increasing by replacement of existing old pumps with new ones. It has been shown that it was possible to identify the pipeline characteristic and an optimum system operating point, even in the absence of appropriate flow measuring devices. This has been done using an indirect method of flow estimation by measurement of driving induction motor elecrtical parameters. In accordance with the obtained results, the new pump has been chosen. Huge savings in the electrical energy consumption referred to actual situation will be achieved through the application of the new pump.Na primeru Crpne stanice "Gnjilan" u okviru JP "Vodovod" Pirot, prikazan je način za povećanje energetske efikasnosti malih pumpnih stanica zamenom postojećih pumpnih agregata novim. Pokazano je da je, čak i u situaciji kada ne postoje odgovarajući uređaji za merenje protoka, moguće identifikovati karakteristiku cevovoda i optimalnu radnu tačku sistema primenom indirektne metode merenja električnih veličina pogonskog motora. U skladu sa identifikovanim parametrima, izvršen je izbor novog pumpnog agregata čijom primenom se mogu ostvariti znatne uštede u odnosu na postojeće stanje sistema

Long-wavelength photonic circuits

Silicon and germanium are transparent in a broad range of the long-wave IR and therefore can be used as photonics platforms in this wavelength region. Furthermore, the free carrier plasma dispersion effect should be stronger, two photon absorption is reduced, and more robust optical bers are now available at longer wavelengths. In addition, the dimensional tolerances are more relaxed than in the near-IR. Moreover, III-V sources and detectors could be bonded on the silicon wafer, similar to approaches already demonstrated in the near-IR. Finally, silicon photonics, or group IV photonics, long wavelength platform is potentially low-cost and offers a possibility of photonicelectronic integration

Long-wavelength photonic circuits

Silicon and germanium are transparent in a broad range of the long-wave IR and therefore can be used as photonics platforms in this wavelength region. Furthermore, the free carrier plasma dispersion effect should be stronger, two photon absorption is reduced, and more robust optical bers are now available at longer wavelengths. In addition, the dimensional tolerances are more relaxed than in the near-IR. Moreover, III-V sources and detectors could be bonded on the silicon wafer, similar to approaches already demonstrated in the near-IR. Finally, silicon photonics, or group IV photonics, long wavelength platform is potentially low-cost and offers a possibility of photonicelectronic integration

Secondary vs. primary pituitary xanthogranulomas: which yellow is more mellow?

Pituitary xanthogranulomatomas (XG) are a rare pathological entity caused by accumulation of lipid laden macrophages and reactive granuloma formation usually triggered by cystic fluid leakage or hemorrhage. Our aim was to compare clinical characteristics and presenting features of patients with secondary etiology of XG and those with no identifiable founding lesion (primary -“pure” XG) in order to gain new insights into this rare pituitary pathology. In a retrospective review of 714 patients operated for sellar masses, at tertiary center, we identified 16 (2.24%) with histologically confirmed diagnosis of pituitary XG over the period of 7 years (2015–2021). Patients were further analyzed according to XG etiology: “pure”- XG (n = 8) with no identifiable founding lesion were compared to those with histological elements of pituitary tumor or cyst – secondary XG (n = 8). We identified 16 patients (11 male), mean age 44.8 ± 22.3 years, diagnosed with pituitary XG. Secondary forms were associated with Ratke’s cleft cyst (RCC, n = 2) and pituitary adenoma (PA, n = 6). The most common presenting features in both groups were hypopituitarism (75%), headache (68.5%) and visual disturbances (37.5%). Predominance of male sex was noted (males 68.75%, females 31.25%), especially in patients with primary forms. Patients with primary pituitary XG were all males (p = 0.0256) and more frequently affected by panhypopituitarism (87.5% vs. 25%, p = 0.0406) compared to patients with secondary causes. Hyperprolactinemia was noted in pituitary tumor group with secondary etiology only (p = 0.0769). Majority of lesions were solid on magnetic resonance imaging - MRI (81.25%). Distinct clinical phenotype was observed dependent on the etiology of XG

Global economic burden of unmet surgical need for appendicitis

Background There is a substantial gap in provision of adequate surgical care in many low- and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US $92 492 million using approach 1 and$73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was $95 004 million using approach 1 and$75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially

Global economic burden of unmet surgical need for appendicitis

Background There is a substantial gap in provision of adequate surgical care in many low- and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US $92 492 million using approach 1 and$73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was $95 004 million using approach 1 and$75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially