Enhancing Micro-Raman Spectroscopy: A Variable Spectral Resolution Instrument Using Zoom Lens Technology.

Raman spectroscopy is a powerful analytical technique based on the inelastic scattering of photons. Conventional macro-Raman spectrometers are suitable for mass analysis but often lack the spatial resolution required to accurately examine microscopic regions of interest. For this reason, the development of micro-Raman spectrometers has been driven forward. However, even with micro-Raman spectrometers, high resolution is required to gain better insight into materials that provide low-intensity Raman signals. Here, we show the development of a micro-Raman spectrometer with implemented zoom lens technology. We found that by replacing a second collimating mirror in the monochromator with a zoom lens, the spectral resolution could be continuously adjusted at different zoom factors, i.e., high resolution was achieved at a higher zoom factor and lower spectral resolution was achieved at a lower zoom factor. A quantitative analysis of a micro-Raman spectrometer was performed and the spectral resolution was analysed by FWHM using the Gaussian fit. Validation was also performed by comparing the results obtained with those of a high-grade laboratory Raman spectrometer. A quantitative analysis was also performed using the ANOVA method and by assessing the signal-to-noise ratio between the two systems.

Broken Rotor Bar Detection Based on Steady-State Stray Flux Signals Using Triaxial Sensor with Random Positioning.

This paper investigates the detection of broken rotor bar in squirrel cage induction motors using a novel approach of randomly positioning a triaxial sensor over the motor surface. This study is conducted on two motors under laboratory conditions, where one motor is kept in a healthy state, and the other is subjected to a broken rotor bar (BRB) fault. The induced electromotive force of the triaxial coils, recorded over ten days with 100 measurements per day, is statistically analyzed. Normality tests and graphical interpretation methods are used to evaluate the data distribution. Parametric and non-parametric approaches are used to analyze the data. Both approaches show that the measurement method is valid and consistent over time and statistically distinguishes healthy motors from those with BRB defects when a reference or threshold value is specified. While the comparison between healthy motors shows a discrepancy, the quantitative analysis shows a smaller estimated difference in mean values between healthy motors than comparing healthy and BRB motors.

Weakly Hard Real-Time Model for Control Systems: A Survey.

The concept of weakly hard real-time systems can be used to model real-time systems that may tolerate occasional deadline misses in a bounded and predictable manner. This model applies to many practical applications and is particularly interesting in the context of real-time control systems. In practice, applying hard real-time constraints may be too rigid since a certain amount of deadline misses is acceptable in some applications. In order to maintain system stability, limitations on the amount and distribution of violated deadlines need to be imposed. These limitations can be formally expressed as weakly hard real-time constraints. Current research in the field of weakly hard real-time task scheduling is focused on designing scheduling algorithms that guarantee the fulfillment of constraints, while aiming to maximize the total number of timely completed task instances. This paper provides an extensive literature review of the work related to the weakly hard real-time system model and its link to the field of control systems design. The weakly hard real-time system model and the corresponding scheduling problem are described. Furthermore, an overview of system models derived from the generalized weakly hard real-time system model is provided, with an emphasis on models that apply to real-time control systems. The state-of-the-art algorithms for scheduling tasks with weakly hard real-time constraints are described and compared. Finally, an overview of controller design methods that rely on the weakly hard real-time model is given.

THE ROLE OF INTERFERON-GAMMA RELEASE ASSAYS IN DIAGNOSIS OF LATENT TUBERCULOSIS INFECTION IN CHILDREN.

Despite numerous published papers, diagnosis of latent tuberculosis infection (LTBI) in children is still an undefined area. The importance of this topic lies in the fact that one third of the world's population is infected with Mycobacterium (M.) tuberculosis. The majority of infected individuals are LTBI cases which make a reservoir for future active tuberculosis (TB) patients. The gold standard for LTBI detection is still undetermined and this is due to the effect of various confounding factors on existing diagnostic tests. Until a decade or so ago, throughout the last century, tuberculin skin test (TST) was the only diagnostic test for LTBI. Due to scientific advances, new in vitro assays, interferon-gamma release assays (IGRAs) were discovered recently. The sensitivities of IGRAs are a bit better than those of TST, while great progress has been made in increasing the specificity of IGRA relative to TST. Nevertheless, in the diagnosis of LTBI in children, TST still has some advantages. However, generations of IGRAs have brought many diagnostic advantages that are emphasized in this review. In a difficult procedure of diagnosing LTBI in children, performance of IGRA could be the key factor in making decision whether to use preventive therapy or not.

INVASIVE FUNGAL INFECTIONS IN CHILDREN TREATED FOR HEMATOLOGIC MALIGNANCIES - A FIVE-YEAR SINGLE CENTER EXPERIENCE.

Invasive fungal infections (IFI) are life-threatening complications of intensive chemotherapy treatment, with the incidence in pediatric patients ranging from 2% to 21%. In this article, we describe our 5-year experience of IFI in pediatric oncology patients and its clinical manifestations with radiological findings, treatment and outcome. A retrospective and descriptive survey of IFI in children with hematologic neoplasms was conducted at the Department of Oncology and Hematology, Zagreb Children's Hospital. Medical charts of children 0-17 years of age, of both sexes, treated for leukemias and lymphomas from January 2016 to December 2020 were reviewed. In a 5-year period, 60 patients were treated for hematologic malignancy, acute lymphoblastic leukemia (ALL) being the most prevalent diagnosis. IFI was verified in 9 (15%) children, predominantly in patients with ALL (75%). The specific causative agent was detected in one child, whereas other infections were classified as probable pulmonary aspergillosis. All the patients received standard prophylaxis with fluconazole and treatment with liposomal amphotericin B and voriconazole. The majority of our patients achieved recovery. IFI prevention, diagnosis and treatment remain a challenge. Uniform prophylaxis and therapy protocols, as well as environmental control are of vital importance for the development of better strategies in the prevention, early detection and treatment of IFI in pediatric hematology patients.

Raman and Photoluminescence Spectroscopy with a Variable Spectral Resolution.

Raman and photoluminescence (PL) spectroscopy are important analytic tools in materials science that yield information on molecules' and crystals' vibrational and electronic properties. Here, we show results of a novel approach for Raman and PL spectroscopy to exploit variable spectral resolution by using zoom optics in a monochromator in the front of the detector. Our results show that the spectral intervals of interest can be recorded with different zoom factors, significantly reducing the acquisition time and changing the spectral resolution for different zoom factors. The smallest spectral intervals recorded at the maximum zoom factor yield higher spectral resolution suitable for Raman spectra. In contrast, larger spectral intervals recorded at the minimum zoom factor yield the lowest spectral resolution suitable for luminescence spectra. We have demonstrated the change in spectral resolution by zoom objective with a zoom factor of 6, but the perspective of such an approach is up to a zoom factor of 20. We have compared such an approach on the prototype Raman spectrometer with the high quality commercial one. The comparison was made on ZrO2 and TiO2 nanocrystals for Raman scattering and Al2O3 for PL emission recording. Beside demonstrating that Raman spectrometer can be used for PL and Raman spectroscopy without changing of grating, our results show that such a spectrometer could be an efficient and fast tool in searching for Raman and PL bands of unknown materials and, thereafter, spectral recording of the spectral interval of interest at an appropriate spectral resolution.

Combined multichannel intraluminal impedance-pH monitoring should be used to diagnose reflux-related otitis media with effusion in children.

AIM: This study investigated the diagnostic usefulness of combined multichannel intraluminal impedance-pH monitoring (MII-pH) in children with suspected reflux-related otitis media with effusion (OME) as existing data were scarce. METHODS: This was a prospective study that included children up to seven years of age who underwent MII-pH due to OME lasting more than three months. The study was conducted in the Children's Hospital Zagreb, Croatia, from January 2014 to August 2016. RESULTS: The study comprised 63 children (63% male) with a mean age of 4.7 years. Gastroesophageal reflux (GER) disease was detected by impedance in 22 (35%) of the children and by pH-metry in nine (14%). In children with OME, MII-pH found a median number of 24 proximal GER episodes, of which a median of nine was acidic and a median of 11 was weakly acidic. There was a significant positive correlation between the number of GER episodes and the presence of eosinophils in nasal swabs. CONCLUSION: Both acidic and weakly acidic refluxes seemed to play a significant role in the pathogenesis of OME. Localised nasal eosinophilia may serve as a marker of extraoesophageal reflux in children with suspected reflux-related OME.

ACUTE RESPIRATORY DISTRESS SYNDROME IN A FOUR-YEAR-OLD BOY WITH DIABETIC KETOACIDOSIS - CASE REPORT.

- Among many disease states as known initiators of acute respiratory distress syndrome (ARDS), diabetic ketoacidosis (DKA) is the rarest one. We present a 4-year-old boy with DKA as the first manifestation of insulin-dependent diabetes mellitus who developed ARDS, required tracheal intubation and mechanical ventilation, and survived without significant sequels. To improve survival of patients with ARDS as a complication of DKA, physicians should be aware of this rare pulmonary complication and its appropriate management.

[Which tuberculin skin test hyperreactive child should be treated with -our experience]. / KOJIM PPD-HIPERREAKTORIMA TREBA DATI PROFILAKSU - NASA ISKUSTVA.

Since persons with latent tuberculosis infection (LTBI) represent a huge reservoir of potential tuberculosis (TB) disease, accurate diagnosis and treatment of LTBI is essential for TB control and eradication. The aim was to assess the diagnostic value of determination of interferon-gamma release assay in school children with hyperreactive tuberculin skin test (TST) reaction. A total of 120 BCG-vaccinated children were investigated due to a hyperreactive TST results. The QuantiFERON-TB Gold In-Tube test (QFT-GIT) was performed. Fifteen children (12.5%) had positive QFT-GIT and 105 (87.5%) children had negative QFT-GIT. There was no statistically significant difference in TST reaction (21.5 mm u QFT+ vs. 20.9 mm u QFT-group, p=0.458). The children with positive QFT-GIT had a statistically higher level of interferon-gamma (IFN-γ) than children with negative QFT-GIT. There were no statistically significant differences in concentrations of IFN-y either basic or upon stimulation with mitogen phytohemagglutinin. After isoniazid prophylaxis QFT-GIT remained positive in two children (p=0.019). In a difficult procedure for diagnosing LTBI in BCG-vaccinated children determination of IFN-γ could be the key factor in making decision whether to use preventive therapy or not.

The effects of parental smoking on anthropometric parameters, peak expiratory flow rate and physical condition in school children.

Passive smoking in children is a considerable health problem, mainly arising from parental smoking. The objectives of the present cross-sectional study were to assess the impact of passive smoking on 1) anthropometric parameters; 2) peak expiratory flow rate (PEFR); and 3) physical condition in school children. The target population included 177 children attending elementary school 5th to 8th grade. Study subjects were divided into two groups according to parental smoking habits. Body weight and height were determined using a digital weighing scale and digital stadiometer; PEFR was measured between 8 a.m. and 10 a.m. using a Peak Flow Meter; and physical condition was assessed by the 6-minute run test. Sixty-six percent of study children were exposed to passive smoking. The children of smoking parents had higher BMI [18.79 (17.50-21.13) kg/m2] than children of nonsmoking parents [17.90 (16.00-20.00) kg/m2; p = 0.036]. There was no statistically significant difference in body height and weight. The children of smoking parents had statistically lower values of PEFR [M(IQR) = 84 (78-88)%, M(IQR) = 94 (89-101)%, respectively; p < 0.0001] and 6-minute run test than children of nonsmoking parents [M(IQR) = 2(1-3), M(IQR) = 4(3-5); respectively; p < 0.0001]. The results of the present study showed that exposure of school children to passive smoking by their parents resulted in an increase of BMI, impairment of lung function, and impairment of physical condition, especially in children of both smoking parents.

Bronchoalveolar lavage cytology in children with chronic unexplained cough and severely neurologically impaired children.

OBJECTIVE: We aimed to compare the cellular composition of bronchoalveolar lavage (BAL) fluids in children with chronic unexplained cough (group 1) and severely neurologically impaired children with chronic or recurrent respiratory problems (group 2) with the BAL cytology of children without pulmonary or systemic diseases (group 3). METHODS: Bronchoscopy with BAL fluid analysis was performed in all subjects. Children with respiratory symptoms underwent 24-hour multichannel intraluminal impedance monitoring. RESULTS: A significant difference was found between the groups in the total number of cells in BAL fluid cytology (191 [range, 24-12,747], 747 [range, 53-13,000], and 105 [range, 41-233] cells/µL, P = .015), in the percentage of neutrophils (21.2 [SD = 32.4], 49.4 [SD = 36.6], and 3.6 [SD = 2.4], P < .001), and in the percentage of lipid-laden macrophages (10.3 [SD = 11.4], 13.7 [SD = 15.8] and 0.44 [SD = 1.0], P < .001). CONCLUSION: The BAL fluid cytology provides useful data for determining the cause of chronic unexplained cough and chronic or recurrent respiratory problems in severely neurologically impaired children.

Pneumonia With Empyema: A Rare Clinical Presentation of Bartonella henselae Infection in a 10-Year-Old Boy.

BACKGROUND: Cat-scratch disease is a common zoonosis in children. However, atypical clinical presentation of cat-scratch disease is less common, and lung involvement is particularly rare. The usual presentation of lung disease in bartonellosis includes other organ involvement and is more common in immunocompromised patients. CASE REPORT: We present a 10-year-old immunocompetent patient with pneumonia and inoculated empyema caused by Bartonella henselae, without any other organ involvement, which occurred 2 weeks after lymphadenopathy. The definite diagnosis was established using the polymerase chain reaction of the empyema obtained from thoracocentesis. The boy was treated with several antibiotics (ceftriaxone, azithromycin, amoxicillin with clavulanic acid, meropenem and vancomycin) and completely recovered after the 3-month follow-up period. CONCLUSIONS: This is a unique case of the difficult-to-treat pneumonia with inoculated empyema, caused by B. henselae, in an immunocompetent child, without any other organ involvement. The clinical course was favorable. A high level of clinical suspicion is mandatory for the diagnosis.

Secondhand Smoke Exposure and Its Impact on Pediatric Lung Function, Aerobic Fitness, and Body Mass: Evidence from a Cross-Sectional Study.

BACKGROUND: Several studies have documented the detrimental impacts of secondhand smoke (SHS) exposure to a range of pediatric respiratory conditions, including asthma, bronchitis, and reduced lung function. The aim of the study was to investigate the influence of SHS exposure on lung function, physical fitness, and body mass index (BMI) in children aged 10 to 14 years. METHODS: This cross-sectional study included children aged 10 to 14 years at the Elementary School "Trilj" in Trilj, Croatia. Data on SHS exposure were collected using a questionnaire. Antropometric and spirometry measurements were performed. Physical fitness was assessed using the shuttle run (BEEP) test. RESULTS: This study included 157 children, 89 (56.69%) boys and 68 (43.31%) girls. Children exposed to every day SHS in households had significantly lower values of forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC, peak expiratory flow (PEF) (p < 0.001) and higher z-score BMI levels (p = 0.018) in comparison to unexposed children. Logistic regression showed that children unexposed to SHS had higher odds for better results in the BEEP test (OR 62.45, 95% CI 21.26-179.24, p < 0.001). Children with poorer physical fitness, expressed by lower BEEP score levels, had significantly lower FVC, FEV1, FEV1/FVC, and PEF (p < 0.001). CONCLUSIONS: Every day SHS exposure in children was associated with poorer lung function, higher BMI, and poorer physical fitness.

Diagnostic Utility of pH-MII Monitoring in Preschool Children with Recurrent Wheeze and Suspected Gastroesophageal Reflux Disease: A Prospective Study.

BACKGROUND: Recurrent wheezing and gastroesophageal reflux disease (GERD) are common in young children, with a suggested but challenging link between them. This study aimed to investigate the diagnostic value of pH-MII monitoring in preschool children with recurrent wheezing and evaluate GERD-related therapy effects. METHODS: Children under 6 years with recurrent wheeze were eligible. The pH-MII monitoring was conducted in those clinically suspected of GERD's involvement. Flexible bronchoscopy with bronchoalveolar lavage (BAL) was performed in severe cases. The primary outcome was the difference in wheezing episodes between proven GERD and non-GERD groups. Secondary outcomes included GERD therapy impact and predictive factors for wheezing reduction. RESULTS: Of 66 children (mean age 3.9 years), 71% had proven GERD on pH-MII. Compared to the non-GERD group, the GERD group had higher total, liquid, mixed, and gas reflux episodes, as well as more acidic and weakly acidic episodes. GERD treatment significantly reduced wheezing episodes. PPI (proton pump inhibitor) introduction was associated with ≥50% wheezing reduction. Children with GERD showed ≥50% wheezing reduction more frequently than those without GERD. PPI usage, higher total GER episodes, acidic episodes, and liquid and proximal episodes on MII predicted ≥50% wheezing reduction. No significant BAL differences were observed between GERD and non-GERD groups. CONCLUSIONS: The pH-MII monitoring is valuable in diagnosing GERD-related wheezing in preschool children. GERD therapy, particularly PPI usage, was associated with reduced wheezing episodes. The pH-MII parameters correlated with wheezing reduction, suggesting their potential predictive role. BAL did not differentiate between GERD and non-GERD cases.

Influence of passive smoking on functional abilities in children.

Passive smoking has been found to be associated with a large number of disorders of passive smokers. It seems that the children are the most susceptible population for harmful effects of passive smoke exposure. The aim of this study was to evaluate the effect of passive smoking on children's functional abilities. The target population was 199 children who were 13-15 years old at the time of the study. For the assessment of motor skills 6-min run test was used. Children exposed to passive smoking by their mothers had statistically significant lower functional abilities (r =-0.7029; 95% CI -0.7707 to -0.6194; p < 0.0001). We also found statistically significant difference if the both parents are smokers (r =-0.3343; 95% CI -0.4595 to -0.1961; p < 0.0001). The results of our study did not show statistically significant difference if the children are exposed to cigarette smoke by their fathers (r = 0.03139; 95% CI -0.1171 to 0.1785; p = 0.6792). Public health preventive actions should go toward minimizing the exposure of children to passive smoking by counseling the smoking parents that quitting smoking provides enormous health benefits not only to them but also to their children.

Risk factors for acute respiratory tract infections in children.

Acute respiratory tract infections (ARTI) are the most common cause of childhood morbidity and an important public health problem. The aim of this study was to identify the significant risk factors for ARTI in children. The study took place in Ivankovo which is a rural area of Eastern Slavonia and with small socio-economic differences. The study population were 159 children who were 3-5 years old at the time of the study, and who were registrated at doctor's office Ivankovo. The study was conducted retrospectively through a questionnaire from January 2008 to December 2008. The risk factors studied were the gender, breastfeeding history, any atopic manifestation in the form of atopic eczema, rhinoconjuctivitis and/or asthma, the size of the family, parents smoking habits and main form of childcare. The number of ARTI requiring the consultation of a doctor throughout 2007 were measured; and whether ARTI had been treated with antibiotic or there were recommendation for symptomatic treatment only. Results of this research show that the risk factor for consulting a doctor because ofARTI in children was passive exposure to cigarette-smoke. For receiving antibiotics because of ARTI in children, the risk factors were passive exposure to cigarette-smoke and atopic manifestation. By giving the available evidence, parents must be told that ceasing smoking offers a significant opportunity to reduce the risk of ARTI in their children.

Achromobacter xylosoxidans Purulent Bronchitis in a Previously Healthy Child: An Unexpected Consequence of COVID-19 Infection.

Achromobacter xylosoxidans is an aerobic, Gram-negative rod with a broad intrinsic and acquired antimicrobial resistance, usually isolated in patients with cystic fibrosis (CF), immunodeficiencies, or those undergoing invasive procedures. We report a case of a previously healthy 14-year-old girl who was hospitalized in our institution due to a prolonged, progressive cough and exertional dyspnea, which started after a mild viral respiratory tract infection. To elucidate the cause of her symptoms, a bronchoscopy was finally performed, showing bilateral purulent bronchitis caused by A. xylosoxidans, isolated from bronchoalveolar lavage (BAL) sample. Since the patient had positive serological testing for coronavirus disease 2019 (COVID-19), we concluded that it was the initial viral infection, although of a mild clinical course, the one that created favorable conditions for proliferation and further inflammation caused by A. xylosoxidans.

The influence of mother's active smoking during pregnancy on body mass index of newborns.

Many investigations have noted bad influence of smoking during pregnancy. In the present article, the influence of mothers smoking during pregnancy on the body mass index (BMI), birth weight and birth length are examined. This retrospective research included 219 children: Group I: 109 children from rural area of east Slavonia (born in General Hospital-Vinkovci) and group II: 110 children from industrial area (born in Zagreb). The questioned subjects were divided into two groups depending on mothers smoking during pregnancy: newborns of mothers who didn't smoke during pregnancy (subgroup A) and newborns of mother who did smoke 10 or more cigarettes per day during pregnancy (subgroup B). Anthropometric parameters (BMI, birth length and birth weight) in newborns of non-smoking mothers were statistically higher (p < 0.05) than in newborns of smoking mothers. Moderate correlation between birth length and birth weight in newborns of non-smoking and smoking mothers from rural area and from non-smoking mothers in urban area was statistically significant, but correlation in the group in newborns of smoking mothers from Zagreb was not statistically significant. Results of this research show that smoking during pregnancy significantly influences the birth weight and birth length. Further investigation is needed, to investigate the lack of correlation between the birth length and birth weight in newborns of smoking mothers from industrial city.

Neglected tuberculous trochanteric bursitis in an adolescent girl: A case report and literature review.

Tuberculous trochanteric bursitis (TTB) is an extremely rare form of extrapulmonary tuberculosis. Due to a low clinical suspicion and poor collaboration among medical professionals, the diagnosis of TTB can be often delayed. In this report, we describe a case of neglected TTB in an adolescent girl that initially presented with right thigh swelling and fluctuance. The patient underwent repeated unsuccessful surgical treatment; however, dull pain and periodic wound drainage remained for eight years. Complete excision of fistula and trochanteric bursa and one year of oral antituberculous drug therapy led to complete recovery. This case report highlights tuberculosis as a diagnostic challenge, when rare localizations are affected. In addition, this report addresses several diagnostic pitfalls and reviews the literature regarding TTB in adolescent patients. Orthopedic surgeons need to consider TTB, when swelling, fluctuance or repeated wound drainage are present on the thigh.

The Role of Combined Multichannel Intraluminal Impedance-pH Monitoring in Infants with Brief, Resolved, Unexplained Events.

PURPOSE: Data on the relationship between gastroesophageal reflux (GER) and brief resolved unexplained events (BRUE) in infants is scarce. The aim of this study was to identify the characteristics of combined multichannel intraluminal impedance-pH (MII-pH) monitoring in infants who have experienced BRUE. METHODS: We conducted a prospective study of infants who were hospitalized on account of BRUE and required 24-hour MII-pH monitoring. RESULTS: Twenty-one infants (mean age, 4.7 months; range, 0.9-8.9 months; male/female, 11/10) participated in this study. BRUE symptoms associated with GER were found in 10 infants (47.6%). Based on the RI on pH-metry alone, only 7 (33.3%) infants were diagnosed with GERD. More than 100 GER episodes detected by MII were found in 10 (47.6%) infants. Nineteen percent of infants were diagnosed with GERD based on both pH and MII. CONCLUSION: Both acid and non-acid reflux seem to play a significant role in the pathogenesis of GER-related BRUE in infants.