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1.
J Infect Dis ; 229(4): 959-968, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37992117

RESUMO

BACKGROUND: Recent data indicate that non-Plasmodium falciparum species may be more prevalent than thought in sub-Saharan Africa. Although Plasmodium malariae, Plasmodium ovale spp., and Plasmodium vivax are less severe than P. falciparum, treatment and control are more challenging, and their geographic distributions are not well characterized. METHODS: We randomly selected 3284 of 12 845 samples collected from cross-sectional surveys in 100 health facilities across 10 regions of Mainland Tanzania and performed quantitative real-time PCR to determine presence and parasitemia of each malaria species. RESULTS: P. falciparum was most prevalent, but P. malariae and P. ovale were found in all but 1 region, with high levels (>5%) of P. ovale in 7 regions. The highest P. malariae positivity rate was 4.5% in Mara and 8 regions had positivity rates ≥1%. We only detected 3 P. vivax infections, all in Kilimanjaro. While most nonfalciparum malaria-positive samples were coinfected with P. falciparum, 23.6% (n = 13 of 55) of P. malariae and 14.7% (n = 24 of 163) of P. ovale spp. were monoinfections. CONCLUSIONS: P. falciparum remains by far the largest threat, but our data indicate that malaria elimination efforts in Tanzania will require increased surveillance and improved understanding of the biology of nonfalciparum species.


Assuntos
Malária Falciparum , Malária , Humanos , Tanzânia/epidemiologia , Estudos Transversais , Malária/epidemiologia , Malária Falciparum/epidemiologia , Plasmodium malariae/genética
2.
Opt Express ; 32(1): 113-124, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175043

RESUMO

High repetition coherent extreme ultraviolet (XUV) harmonics offer a powerful tool for investigating electron dynamics and understanding the underlying physics in a wide range of systems. We demonstrate the utilization of combined three-color (ω+2ω+3ω) laser fields in the generation of coherent extreme ultraviolet radiation in mixed noble gases. The three-color field results from the combination of fundamental, second-, and third-order harmonics of the near-infrared laser pulses in the nonlinear crystals. Different noble gases were selected as gas targets based on their ionization potentials, which are important parameters for generating higher cut-offs and intensities for the XUV harmonics. Enhanced XUV harmonic intensities were observed in the mixture of He + Kr gases when using three-color laser fields, compared to harmonics generated in the He + Kr mixture under a single-color pump. On the other hand, suppression of XUV harmonic intensity was observed in the mixture of He + Xe under the three-color pump due to the highest ionization level for these two mixed gases at similar laser conditions. Strong harmonic yields in the range of 25 to 80 eV of photon energy were observed.

3.
Malar J ; 23(1): 197, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926854

RESUMO

BACKGROUND: Although Tanzania adopted and has been implementing effective interventions to control and eventually eliminate malaria, the disease is still a leading public health problem, and the country experiences heterogeneous transmission. Recent studies reported the emergence of parasites with artemisinin partial resistance (ART-R) in Kagera region with high prevalence (> 10.0%) in two districts of Karagwe and Kyerwa. This study assessed the prevalence and predictors/risk of malaria infections among asymptomatic individuals living in a hyperendemic area where ART-R has emerged in Kyerwa District of Kagera region, north-western Tanzania. METHODS: This was a community-based cross-sectional survey which was conducted in July and August 2023 and involved individuals aged ≥ 6 months from five villages in Kyerwa district. Demographic, anthropometric, clinical, parasitological, type of house inhabited and socio-economic status (SES) data were collected using electronic capture tools run on Open Data Kit (ODK) software. Predictors/risks of malaria infections were determined by univariate and multivariate logistic regression, and the results were presented as crude (cORs) and adjusted odds ratios (aORs), with 95% confidence intervals (CIs). RESULTS: Overall, 4454 individuals were tested using rapid diagnostic tests (RDTs), and 1979 (44.4%) had positive results. The prevalence of malaria infections ranged from 14.4% to 68.5% and varied significantly among the villages (p < 0.001). The prevalence and odds of infections were significantly higher in males (aOR = 1.28, 95% CI 1.08 -1.51, p = 0.003), school children (aged 5-≤10 years (aOR = 3.88, 95% CI 3.07-4.91, p < 0.001) and 10-≤15 years (aOR = 4.06, 95% CI 3.22-5.13, p < 0.001)) and among individuals who were not using bed nets (aOR = 1.22, 95% CI 1.03-1.46, p = 0.024). The odds of malaria infections were also higher in individuals with lower SES (aOR = 1.42, 95% CI 1.17-1.72, p < 0.001), and living in houses without windows (aOR = 2.08, 95% CI 1.46-2.96, p < 0.001), partially open (aOR = 1.33, 95% CI 1.11-1.58, p = 0.002) or fully open windows (aOR = 1.30, 95%CI 1.05-1.61, p = 0.015). CONCLUSION: The five villages had a high prevalence of malaria infections and heterogeneity at micro-geographic levels. Groups with higher odds of malaria infections included school children, males, and individuals with low SES, living in poorly constructed houses or non-bed net users. These are important baseline data from an area with high prevalence of parasites with ART-R and will be useful in planning interventions for these groups, and in future studies to monitor the trends and potential spread of such parasites, and in designing a response to ART-R.


Assuntos
Antimaláricos , Artemisininas , Tanzânia/epidemiologia , Masculino , Prevalência , Feminino , Humanos , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Estudos Transversais , Criança , Pré-Escolar , Adolescente , Adulto , Adulto Jovem , Antimaláricos/uso terapêutico , Antimaláricos/farmacologia , Pessoa de Meia-Idade , Lactente , Resistência a Medicamentos , Malária/epidemiologia , Idoso , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Fatores de Risco , Plasmodium falciparum/efeitos dos fármacos
4.
Malar J ; 23(1): 79, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491359

RESUMO

BACKGROUND: Tanzania is currently implementing therapeutic efficacy studies (TES) in areas of varying malaria transmission intensities as per the World Health Organization (WHO) recommendations. In TES, distinguishing reinfection from recrudescence is critical for the determination of anti-malarial efficacy. Recently, the WHO recommended genotyping polymorphic coding genes, merozoite surface proteins 1 and 2 (msp1 and msp2), and replacing the glutamate-rich protein (glurp) gene with one of the highly polymorphic microsatellites in Plasmodium falciparum to adjust the efficacy of antimalarials in TES. This study assessed the polymorphisms of six neutral microsatellite markers and their potential use in TES, which is routinely performed in Tanzania. METHODS: Plasmodium falciparum samples were obtained from four TES sentinel sites, Kibaha (Pwani), Mkuzi (Tanga), Mlimba (Morogoro) and Ujiji (Kigoma), between April and September 2016. Parasite genomic DNA was extracted from dried blood spots on filter papers using commercial kits. Genotyping was done using six microsatellites (Poly-α, PfPK2, TA1, C3M69, C2M34 and M2490) by capillary method, and the data were analysed to determine the extent of their polymorphisms and genetic diversity at the four sites. RESULTS: Overall, 83 (88.3%) of the 94 samples were successfully genotyped (with positive results for ≥ 50.0% of the markers), and > 50.0% of the samples (range = 47.6-59.1%) were polyclonal, with a mean multiplicity of infection (MOI) ranging from 1.68 to 1.88 among the four sites. There was high genetic diversity but limited variability among the four sites based on mean allelic richness (RS = 7.48, range = 7.27-8.03, for an adjusted minimum sample size of 18 per site) and mean expected heterozygosity (He = 0.83, range = 0.80-0.85). Cluster analysis of haplotypes using STRUCTURE, principal component analysis, and pairwise genetic differentiation (FST) did not reveal population structure or clustering of parasites according to geographic origin. Of the six markers, Poly-α was the most polymorphic, followed by C2M34, TA1 and C3M69, while M2490 was the least polymorphic. CONCLUSION: Microsatellite genotyping revealed high polyclonality and genetic diversity but no significant population structure. Poly-α, C2M34, TA1 and C3M69 were the most polymorphic markers, and Poly-α alone or with any of the other three markers could be adopted for use in TES in Tanzania.


Assuntos
Antimaláricos , Malária Falciparum , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Proteínas de Protozoários/metabolismo , Malária Falciparum/parasitologia , Variação Genética , Tanzânia , Proteína 1 de Superfície de Merozoito/genética , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Genótipo , Repetições de Microssatélites , Antígenos de Protozoários/genética
5.
Malar J ; 23(1): 71, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461239

RESUMO

BACKGROUND: Therapeutic efficacy studies (TESs) and detection of molecular markers of drug resistance are recommended by the World Health Organization (WHO) to monitor the efficacy of artemisinin-based combination therapy (ACT). This study assessed the trends of molecular markers of artemisinin resistance and/or reduced susceptibility to lumefantrine using samples collected in TES conducted in Mainland Tanzania from 2016 to 2021. METHODS: A total of 2,015 samples were collected during TES of artemether-lumefantrine at eight sentinel sites (in Kigoma, Mbeya, Morogoro, Mtwara, Mwanza, Pwani, Tabora, and Tanga regions) between 2016 and 2021. Photo-induced electron transfer polymerase chain reaction (PET-PCR) was used to confirm presence of malaria parasites before capillary sequencing, which targeted two genes: Plasmodium falciparum kelch 13 propeller domain (k13) and P. falciparum multidrug resistance 1 (pfmdr1). RESULTS: Sequencing success was ≥ 87.8%, and 1,724/1,769 (97.5%) k13 wild-type samples were detected. Thirty-seven (2.1%) samples had synonymous mutations and only eight (0.4%) had non-synonymous mutations in the k13 gene; seven of these were not validated by the WHO as molecular markers of resistance. One sample from Morogoro in 2020 had a k13 R622I mutation, which is a validated marker of artemisinin partial resistance. For pfmdr1, all except two samples carried N86 (wild-type), while mutations at Y184F increased from 33.9% in 2016 to about 60.5% in 2021, and only four samples (0.2%) had D1246Y mutations. pfmdr1 haplotypes were reported in 1,711 samples, with 985 (57.6%) NYD, 720 (42.1%) NFD, and six (0.4%) carrying minor haplotypes (three with NYY, 0.2%; YFD in two, 0.1%; and NFY in one sample, 0.1%). Between 2016 and 2021, NYD decreased from 66.1% to 45.2%, while NFD increased from 38.5% to 54.7%. CONCLUSION: This is the first report of the R622I (k13 validated mutation) in Tanzania. N86 and D1246 were nearly fixed, while increases in Y184F mutations and NFD haplotype were observed between 2016 and 2021. Despite the reports of artemisinin partial resistance in Rwanda and Uganda, this study did not report any other validated mutations in these study sites in Tanzania apart from R622I suggesting that intensified surveillance is urgently needed to monitor trends of drug resistance markers and their impact on the performance of ACT.


Assuntos
Antimaláricos , Artemisininas , Carrubicina/análogos & derivados , Malária Falciparum , Humanos , Lumefantrina/farmacologia , Lumefantrina/uso terapêutico , Plasmodium falciparum/genética , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Tanzânia , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Artemeter/uso terapêutico , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Combinação Arteméter e Lumefantrina/farmacologia , Combinação Arteméter e Lumefantrina/uso terapêutico , Malária Falciparum/epidemiologia , Biomarcadores , Resistência a Medicamentos/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/uso terapêutico
6.
Sleep Breath ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264534

RESUMO

BACKGROUND: In today's modern world, shift working has become an important part of society and industrial work; prolonged wakefulness is a widespread phenomenon due to which the sleep patterns of individuals are getting disturbed, and many sleep disorders are arising. PURPOSE: This study compared the sleep quality and insomnia of the security guards working the day and night shifts. METHODS: This observational study comprised 100 security guards from Delhi and the NCR region. Self-administered questionnaires, i.e., the Pittsburgh sleep quality index (PSQI) and the Athens Insomnia Scale (AIS), were used to assess sleep quality and insomnia. Fifty questionnaires were filled out by the day shift security guards, and the night shift security guards filled out 50. The data underwent analysis, and a comparison was conducted between security workers on night and day shifts using a Mann-Whitney U test, with a significance level set at p < 0.05. RESULTS: The result revealed a significant difference (95% CI; p < 0.05) for the variables, sleep quality and insomnia when compared between night and day shift working security guards. Among night shift workers, 74% reported issues with sleep quality and 48% experienced insomnia. In comparison, among day shift workers, 58% reported concerns about sleep quality, while 32% reported experiencing insomnia. CONCLUSION: The study concluded that night-shift working security guards had poorer sleep quality and a higher prevalence of insomnia compared to their day-shift counterparts. These differences are highly significant, highlighting the potential adverse effects of night shift work on sleep health, urging the need for interventions to improve sleep quality and manage insomnia among night shift workers.

7.
Health Expect ; 27(2): e14038, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38561909

RESUMO

BACKGROUND: More than three-fourths of cervical cancer cases occur in low- and middle-income countries, with sub-Saharan Africa (SSA) accounting for approximately 25% of global mortality. The significant rise in the prevalence of cervical cancer in SSA amplifies the burden on caregivers, contributing to elevated rates of mental illness, particularly among spouses who provide care. Men who assume the role of caregivers for their partners with cervical cancer encounter unique challenges and substantial adjustments across multiple facets of life, impacting both their own quality of life and that of their partners. Despite this, there is a notable lack of extensive research on the experiences of male partners in caregiving roles, particularly within SSA countries like Tanzania. Therefore, this study aimed to explore the experiences of male partners providing care for women with cervical cancer in Dar es Salaam, Tanzania. METHODS: An exploratory qualitative study was undertaken to explore the experiences of 13 male partners, selected purposively and guided by the principle of saturation. Data gathering employed in-depth interviews utilizing a semistructured interview guide, with subsequent analysis conducted via a thematic analysis approach. RESULTS: Five themes and 13 subthemes were generated, encompassing psychosocial distress, attitudes towards cervical cancer, unity in the provision of care, economic burden, and altered sexual relationships. Participants reported experiencing emotional distress, shifts in social responsibilities, financial challenges, and unfulfilled sexual needs. Moreover, they expressed the need for social, psychological, financial, and sexual and reproductive support. CONCLUSION: This study underscores the numerous challenges encountered by male partners caring for women with cervical cancer, encompassing emotional distress, financial strain, and shifts in social and sexual dynamics. The identified themes and subthemes highlight the intricate interplay of these difficulties and stress the necessity for holistic support systems addressing the social, psychological, financial, and sexual aspects of male partners' experiences. The findings emphasize the importance of designing and implementing comprehensive support programmes tailored to the diverse needs of male partners, ultimately enhancing their quality of life and overall well-being. PATIENT OR PUBLIC CONTRIBUTION: Before the study, the nursing manager assisted in selecting three male partners randomly. These partners were involved in the design of the participants' information sheet, the evaluation of the interview schedule and rooms, and the dissemination of information about the study's purpose to the target population. Their valuable input contributed to improving the participant information sheet, refining data collection procedures and addressing ethical considerations. However, these individuals were not considered study participants. Throughout the study, in-charge nurses in the hospital were informed about the study's goals and helped organize appointments with participants and manage the interview schedule.


Assuntos
Neoplasias do Colo do Útero , Humanos , Masculino , Feminino , Tanzânia/epidemiologia , Qualidade de Vida , Comportamento Sexual/psicologia , Pesquisa Qualitativa
8.
J Cardiothorac Vasc Anesth ; 38(4): 895-904, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38307740

RESUMO

OBJECTIVE: To test the correlation of ejection fraction (EF) estimated by a deep-learning-based, automated algorithm (Auto EF) versus an EF estimated by Simpson's method. DESIGN: A prospective observational study. SETTING: A single-center study at the Hospital of the University of Pennsylvania. PARTICIPANTS: Study participants were ≥18 years of age and scheduled to undergo valve, aortic, coronary artery bypass graft, heart, or lung transplant surgery. INTERVENTIONS: This noninterventional study involved acquiring apical 4-chamber transthoracic echocardiographic clips using the Philips hand-held ultrasound device, Lumify. MEASUREMENTS AND MAIN RESULTS: In the primary analysis of 54 clips, compared to Simpson's method for EF estimation, bias was similar for Auto EF (-10.17%) and the experienced reader-estimated EF (-9.82%), but the correlation was lower for Auto EF (r = 0.56) than the experienced reader-estimated EF (r = 0.80). In the secondary analyses, the correlation between EF estimated by Simpson's method and Auto EF increased when applied to 27 acquisitions classified as adequate (r = 0.86), but decreased when applied to 27 acquisitions classified as inadequate (r = 0.46). CONCLUSIONS: Applied to acquisitions of adequate image quality, Auto EF produced a numerical EF estimate equivalent to Simpson's method. However, when applied to acquisitions of inadequate image quality, discrepancies arose between EF estimated by Auto EF and Simpson's method. Visual EF estimates by experienced readers correlated highly with Simpson's method in both variable and inadequate imaging conditions, emphasizing its enduring clinical utility.


Assuntos
Aprendizado Profundo , Salas Cirúrgicas , Humanos , Volume Sistólico , Sistemas Automatizados de Assistência Junto ao Leito , Ecocardiografia/métodos , Algoritmos , Reprodutibilidade dos Testes , Função Ventricular Esquerda
9.
Int J Mol Sci ; 25(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39125674

RESUMO

The molecular laser-induced plasma (LIP) produced during the ablation of silver sulfide (Ag2S) was used as a medium for high-order harmonic generation in the extreme ultraviolet range. The role of LIP formation, the plasma components, and the geometry of plasma in the harmonic conversion efficiency was analyzed. We also analyzed the influence of the driving pulses (chirp, single-color pump, two-color pump, and delay between heating and converting pulses) on the harmonic yield in Ag2S LIP. The application of molecular plasma was compared with the application of atomic plasma, which comprised similar metallic elements (Ag) as well as other metal LIPs. The harmonics from the Ag2S LIP were 4 to 10 times stronger than those from the Ag LIP. The harmonics up to the 59th order were achieved under the optimal conditions for the molecular plasma.


Assuntos
Gases em Plasma , Compostos de Prata , Compostos de Prata/química , Lasers
10.
Khirurgiia (Mosk) ; (10): 121-129, 2024.
Artigo em Russo | MEDLINE | ID: mdl-39422015

RESUMO

We demonstrate the peculiarities of diagnosis and successful multi-stage treatment of a patient with severe combined trauma and heart rupture complicated by extensive ischemic stroke in early postoperative period. A patient with severe combined injury was treated at the trauma center grade 3 (State Clinical Hospital No. 25, Volgograd) in 2023. We should remember Beck's triad and possible sternum fracture as a marker of severe chest injury for timely diagnosis of heart rupture with pericardial tamponade. Successful multi-stage treatment of a patient with severe combined trauma and cardiac rupture complicated by extensive ischemic stroke in early postoperative period was demonstrated.


Assuntos
Ruptura Cardíaca , AVC Isquêmico , Humanos , Masculino , Ruptura Cardíaca/etiologia , Ruptura Cardíaca/diagnóstico , Ruptura Cardíaca/cirurgia , AVC Isquêmico/etiologia , AVC Isquêmico/cirurgia , AVC Isquêmico/diagnóstico , Resultado do Tratamento , Traumatismo Múltiplo/complicações , Traumatismo Múltiplo/cirurgia , Tamponamento Cardíaco/etiologia , Tamponamento Cardíaco/cirurgia , Tamponamento Cardíaco/diagnóstico , Traumatismos Torácicos/complicações , Traumatismos Torácicos/diagnóstico , Traumatismos Torácicos/cirurgia , Procedimentos Cirúrgicos Cardíacos/métodos , Adulto
11.
Malays J Med Sci ; 31(4): 35-49, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39247111

RESUMO

Chemotherapeutic drugs have demonstrated effectiveness in treating various neoplastic conditions; however, they can also have detrimental effects on male gonadal function and fertility. Consequently, interest has grown in identifying novel approaches that can mitigate chemotherapy-induced testicular damage. Thymoquinone (TQ), the chief active component of the volatile oil of Nigella sativa (NS), has a wide range of therapeutic properties, including antioxidant, anti-inflammatory and anti-apoptotic effects. The aim of this systematic review was to identify experimental animal studies that have evaluated the protective effects of TQ against testicular complications associated with chemotherapy. In accordance with the preferred reporting items for systematic review and meta-analyses (PRISMA) guidelines, a thorough search was performed across several databases (PubMed, EBSCOhost, Sage and Scopus) to identify experimental studies published from 2010 to May 2022 that focused on rodent models and compared the effects of TQ versus other chemotherapeutic drugs. Eight studies met the inclusion criteria, comparing TQ with methotrexate (MTX), 6-mercaptopurine (6-MP), cyclophosphamide (CPA), bleomycin (BL), doxorubicin (DOX) or busulfan (BUS). The results of these studies consistently demonstrated that TQ significantly improved sperm parameters, the levels of oxidative stress (OS) markers, apoptosis markers, and hormones and testicular histopathology, indicating that TQ has protective effects against chemotherapy-induced damage. TQ mitigated chemotherapy-induced testicular toxicity by decreasing lipid peroxidation and enhancing the activity of antioxidant enzymes within chemotherapy-treated testes. These findings highlight the potential of TQ as a therapeutic agent that can ameliorate testicular complications associated with chemotherapy, thereby providing a basis for further research and potential therapeutic applications.

12.
J Viral Hepat ; 30(7): 621-629, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37084170

RESUMO

Stigma associated with hepatitis B virus (HBV) is common in endemic countries; however; instruments are lacking to accurately measure HBV-related stigma. We therefore aimed to develop and validate a concise instrument for measuring perceived HBV-related stigma in Sierra Leone. We enrolled 220 people living with HBV (PWHB) aged ≥18 years from August to November 2022. The initial Likert-scale instrument entailed 12 items adapted from Berger's HIV Stigma Scale. We included four additional items adapted from the USAID indicators for enacted stigma. The proposed scale's psychometric properties were assessed. After item reduction, the final HBV Stigma Scale consisted of 10 items and had good internal consistency (overall Cronbach's α = 0.74), discriminant, and construct validity. Exploratory factor analysis produced a three-dimensional structure accounting for 59.3% of variance: personalized stigma driven by public attitudes (six items), negative self-image (two items), and disclosure concerns (two items). Overall, 72.8% of respondents reported perceived HBV-related stigma (mean score 29.11 ± 4.14) and a similar proportion (73.6%) reported at least one instance of enacted stigma. In assessing criterion-related validity, perceived HBV-related stigma correlated strongly with enacted stigma (r = 0.556) and inversely with having family/friends with HBV (r = -0.059). The 10-item HBV Stigma Scale demonstrated good internal consistency and validity and is suitable for screening for HBV-related stigma in Sierra Leone. The psychometric properties of the scale can be optimized with item additions/modifications and confirmatory factor analysis. The scale may help in combating stigma as a barrier to achieving HBV global elimination goals.


Assuntos
Infecções por HIV , Hepatite B , Humanos , Adolescente , Adulto , Vírus da Hepatite B , Serra Leoa , Estigma Social
13.
Opt Express ; 31(26): 43748-43763, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38178464

RESUMO

The resonance-enhanced harmonics in laser-induced arsenic and selenium plasmas are studied at the quasi-phase-matching (QPM) conditions. We demonstrate that the enhancement of these harmonics was significantly smaller than the one of the neighboring harmonics. Though the enhancement factors of the harmonics in the vicinity of resonance-enhanced harmonics were in the range of 5× to 18×, the resonance-enhanced harmonics were almost unenhanced at QPM conditions. The most probable reason for such restriction in the enhancement of specific harmonics at the conditions of QPM was a stronger influence of free electrons on the phase-matching conditions of the resonance-enhanced single harmonic compared to the QPM-enhanced group of harmonics.

14.
Opt Express ; 31(16): 26626-26642, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710519

RESUMO

We demonstrate the generation of high-order harmonics of laser pulses in palladium and cadmium plasmas. We adjusted the wavelength of driving pulses to investigate the resonance enhancement in different ranges of extreme ultraviolet region. The summation of incommensurate waves during the two-color pump of Pd and Cd plasmas allowed the generation of a broader range of harmonics. The theoretical aspects of the two-color pump of the laser-induced plasma are discussed.

15.
Malar J ; 22(1): 304, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37817185

RESUMO

BACKGROUND: Despite significant decline in the past two decades, malaria is still a major public health concern in Tanzania; with over 93% of the population still at risk. Community knowledge, attitudes and practices (KAP), and beliefs are key in enhancing uptake and utilization of malaria control interventions, but there is a lack of information on their contribution to effective control of the disease. This study was undertaken to determine KAP and beliefs of community members and service providers on malaria, and how they might be associated with increased risk and persistence of the disease burden in North-western and Southern regions of Tanzania. METHODS: This was an exploratory study that used qualitative methods including 16 in-depth interviews (IDI) and 32 focus group discussions (FGDs) to collect data from health service providers and community members, respectively. The study was conducted from September to October 2017 and covered 16 villages within eight districts from four regions of mainland Tanzania (Geita, Kigoma, Mtwara and Ruvuma) with persistently high malaria transmission for more than two decades. RESULTS: Most of the participants had good knowledge of malaria and how it is transmitted but some FGD participants did not know the actual cause of malaria, and thought that it is caused by bathing and drinking un-boiled water, or consuming contaminated food that has malaria parasites without warming it. Reported barriers to malaria prevention and control (by FGD and IDI participants) included shortage of qualified health workers, inefficient health financing, low care-seeking behaviour, consulting traditional healers, use of local herbs to treat malaria, poverty, increased breeding sites by socio-economic activities and misconceptions related to the use of bed nets and indoor residual spraying (IRS). Among the misconceptions, some participants believed that bed nets provided for free by the government came with bedbugs while others reported that free bed nets caused impotence among men. CONCLUSION: Despite good knowledge of malaria, several risk factors, such as socio-economic and behavioural issues, and misconceptions related to the use of bed nets and IRS were reported. Other key factors included unavailability or limited access to health services, poor health financing and economic activities that potentially contributed to persistence of malaria burden in these regions. Relevant policies and targeted malaria interventions, focusing on understanding socio-cultural factors, should be implemented to reduce and finally eliminate the disease in the study regions and others with persistent transmission.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Malária , Masculino , Humanos , Tanzânia , Controle de Mosquitos/métodos , Malária/epidemiologia , Fatores de Risco
16.
Clin Radiol ; 78(1): 47-54, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36220736

RESUMO

AIM: To assess qualitative and quantitative magnetic resonance imaging (MRI) factors that can help distinguish leiomyosarcoma (LMS) from benign degenerative leiomyoma (BDL) and leiomyoma variants (LV) and assess the interobserver agreement for the proposed quantitative factors. MATERIALS AND METHODS: Retrospective analysis of all histopathology proven cases of LV, BDL, and LMS with a preoperative MRI was performed. Twenty-seven cases were included (five LMS, three LV, and 19 BDL) with each case independently read by a pair of radiologists. Lesion size, margins, presence or absence of degeneration, necrosis, and haemorrhage were assessed on MRI along with quantitative factors such as mean T2-weighted (W) and T1W signal intensity, T1W signal heterogeneity, diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC) ratios as well as dynamic contrast enhancement (DCE) characteristics along with the presence or absence of lymphadenopathy and extra-uterine and peritoneal spread. Mean and standard deviation for quantitative variables and frequency with percentages for qualitative variables were assessed. RESULTS: Infiltrative margins were seen exclusively in the LMS group (n=1), with the remaining LMS cases showing lobulate or rounded smooth margins similar to BDL or LV. A high T2W signal <25% was seen exclusively in the BDL group (n=8). The presence of concomitant necrosis and haemorrhage was seen exclusively in the LMS group (n=2). Quantitative MRI had good inter-reader correlation but was not significantly different between the LMS, BDL, and LV groups. CONCLUSION: LMS, BDL, and LV may have overlapping features on multiparametric MRI making differentiation difficult.


Assuntos
Leiomioma , Leiomiossarcoma , Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias Pélvicas , Neoplasias Uterinas , Feminino , Humanos , Leiomiossarcoma/diagnóstico por imagem , Leiomiossarcoma/patologia , Estudos Retrospectivos , Diagnóstico Diferencial , Leiomioma/diagnóstico por imagem , Leiomioma/patologia , Neoplasias Uterinas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética , Necrose
17.
Sensors (Basel) ; 23(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36772628

RESUMO

In recent years, the development of wireless technologies has led to fast growth in mobile networks, especially with the rise of 5G New Radio (5G NR). A huge number of base stations (BSs) are mandatory to serve the growth of mobile services, which has led to concerns about the increase in electromagnetic field (EMF) radiation exposure levels. To control the overall power emitted by EMF transmitters, international bodies have set maximum exposure limits. This paper investigates the compliance distances (CDs) of shared sites by a group of Mobile Network Operators (MNO) as multi-operators operating with multi-technology and sharing the same tower. The study investigated the CDs of the most two commonly used types of sharing sites, macro and indoor-Based solution sites (IBS). In addition, the study analyzed the power densities and total exposure ratios for the general public and occupational workers in each sharing scenario. The results showed that, compared with a single MNO, the CD increased by 41% in the case of two MNOs, 73% for three MNOs, and 100% for four MNOs. The EMF site sharing scale-up formula was used to estimate the increase in CDs for N number of MNOs assuming that all MNOs use the same site configuration. In addition, the results showed that 5G has the highest contribution to the total exposure ratio (TER) at the CD in the main direction of the antennae.

18.
Int J Mol Sci ; 24(7)2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37047513

RESUMO

The transition metal dichalcogenides have instigated a lot of interest as harmonic generators due to their exceptional nonlinear optical properties. Here, the molybdenum disulfide (MoS2) molecular structures with dopants being in a plasma state are used to demonstrate the generation of intense high-order harmonics. The MoS2 nanoflakes and nickel-doped MoS2 nanoflakes produced stronger harmonics with higher cut-offs compared with Mo bulk and MoS2 bulk. Conversely, the MoS2 with nickel nanoparticles and carbon nanotubes (MoS2-NiCNT) produced weaker coherent XUV emissions than other materials, which is attributed to the influence of phase mismatch. The influence of heating and driving pulse intensities on the harmonic yield and cut-off energies are investigated in MoS2 molecular structures. The enhanced coherent extreme ultraviolet emission at ~32 nm (38 eV) due to the 4p-4d resonant transitions is obtained from all aforementioned molecular structures, except for MoS2-NiCNT.


Assuntos
Nanotubos de Carbono , Elementos de Transição , Níquel , Molibdênio , Frequência Cardíaca
19.
Med J Malaysia ; 78(5): 566-569, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37775480

RESUMO

INTRODUCTION: The prevalence of cerebral palsy (CP) in Malaysia is estimated at 2.6 per 1000 live births which is comparable to that of Australian and European data with ranges of 2.3- 4.21,2. Surgical intervention for the improvement of gait function and mobility in CP is a common practice, however scarce literature of its outcomes is available in Southeast Asia. This paper aims to address and compare outcomes of surgical interventions in our centre with other countries. MATERIAL AND METHODS: Patients with Spastic CP with Gross Motor Function Classification System (GMFCS) I-III that underwent lower limb surgical intervention in our centre from 2008-2018 were retrospectively reviewed for The Spinal Alignment and Range of Motion Measure ROM subscale (SAROMM) scores and Functional Mobility Scale (FMS) 18 months after surgery. Changes in SAROMM, FMS scores and minimal clinically important difference (MCID) were determined. RESULTS: 19 patients were included in the study with mean age of 12.58. All patients underwent muscle tendon procedures. Box plot analysis of SAROMM showed reduction of median scores at 6(26.3%) and 12(47.4%) months which plateaus at 18 months post-surgery. Repeated measure ANOVA analysis showed there was a statistically significant effect of time on SAROMM scores (p <0.001) with MCID of 13.4. Improvement of FMS scores was the most at 50m with 13 children (p < 0.05), one at 5m and five at 500m. None reported worsening of FMS scores at 18 months. There were no changes of GMFCS levels by the end of 18 months. CONCLUSION: Surgeries performed on GMFCS I-III patients with the aim of gait improvement translates into improved mobility with results comparable to other countries.

20.
Cluster Comput ; 26(1): 575-586, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35602318

RESUMO

In recent times, energy related issues have become challenging with the increasing size of data centers. Energy related issues problems are becoming more and more serious with the growing size of data centers. Green cloud computing (GCC) becomes a recent computing platform which aimed to handle energy utilization in cloud data centers. Load balancing is generally employed to optimize resource usage, throughput, and delay. Aiming at the reduction of energy utilization at the data centers of GCC, this paper designs an energy efficient resource scheduling using Cultural emperor penguin optimizer (CEPO) algorithm, called EERS-CEPO in GCC environment. The proposed model is aimed to distribute work load amongst several data centers or other resources and thereby avoiding overload of individual resources. The CEPO algorithm is designed based on the fusion of cultural algorithm (CA) and emperor penguin optimizer (EPO), which boosts the exploitation capabilities of EPO algorithm using the CA, shows the novelty of the work. The EERS-CEPO algorithm has derived a fitness function to optimally schedule the resources in data centers, minimize the operational and maintenance cost of the GCC, and thereby decrease the energy utilization and heat generation. To ensure the improvised performance of the EERS-CEPO algorithm, a wide range of experiments is performed and the experimental outcomes highlighted the better performance over the recent state of art techniques.

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