RESUMO
PURPOSE: To assess the various patterns of the inter-proximal contact areas of the permanent dentition using the available cone beam computed tomography (CBCT) images. METHODS: A retrospective cross-sectional study was performed on existing CBCT images from a University hospital and teaching department. Three thousand two hundred and fifty inter-proximal contacts were assessed from 125 existing CBCT scans of patients (age range: 14 years 3 months-29 years 9 months) who had matched the eligibility criteria. The types of inter-proximal contacts of the permanent dentition were scored at occlusal, middle, and cervical thirds, according to the OXIS inter-proximal contacts classification. Chi-square test was used to assess the contacts and gender/arches. RESULTS: The most prevalent contact was type I for the posterior teeth contacts, and types S1 and S2 for the anterior teeth contacts. Statistical significance was not observed between the contacts on the left and right sides (P > 0.05), while statistical significance was observed between the inter-proximal contacts of the maxilla and mandible (P < 0.05). CONCLUSION: The CBCT-based three-dimensional assessment of the inter-proximal contact areas of the permanent dentition is representative of the OXIS classification. The occlusal level contact was predominantly representative of the overall type of the contact.
Assuntos
Tomografia Computadorizada de Feixe Cônico , Dentição Permanente , Imageamento Tridimensional , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Adolescente , Estudos Retrospectivos , Feminino , Estudos Transversais , Masculino , Imageamento Tridimensional/métodos , Adulto , Adulto Jovem , Maxila/diagnóstico por imagemRESUMO
Oral submucous fibrosis (OSMF) is a premalignant condition associated with chewing areca nut and tobacco products. We observed increased fluoride levels in some OSMF-endemic regions,and the observation suggested that fluoride exposure may contribute to its pathogenesis. This study aimed to assess the fluoride content of various smokeless tobacco items as a potential influencing source. Fluoride concentration was analysed in commercial areca nut products, including gutkha, pan masala, and raw areca nut, along with tobacco, slaked lime, and catechu samples from Karnataka, India. Fluoride was measured using alkali fusion and the ion selective electrode method. All products showed high fluoride, with catechu having the highest mean concentration at 51.20 mg/kg, followed by tobacco, gutkha, pan masala, processed areca nut, and raw areca nut. Fluoride was also elevated in soil, but not in water. The findings demonstrate substantial fluoride levels in popular types of smokeless tobacco, and highlight an overlooked source of exposure among consumers of gutkha, pan masala and similar oral tobacco-products. The fluoride content warrants an investigation of potential links with the occurrence and severity of OSMF.
Assuntos
Fibrose Oral Submucosa , Tabaco sem Fumaça , Humanos , Fluoretos , Areca , Projetos Piloto , Nozes , ÍndiaRESUMO
Introduction: Undiagnosed hypertension (HTN) increases the risk of severe consequences such as chronic kidney disease (CKD), hypertensive retinopathy, heart failure, and stroke. Population-based screening can be used to expose the hidden diseased mass with active disease. Thus, a screening survey was conducted to estimate the proportion of people with HTN among apparently healthy adults of age ≥30 years residing at the urban field practice area (UHTC) of AIIMS, Raipur, and also determine the predictors of undiagnosed HTN among the study participants. Methodology: This was a community-based cross-sectional study conducted over 2 months duration in the Ramnagar area, which comes under the urban field practice area of AIIMS Raipur using the STEPS tool is an acronym of study tool provided by WHO i.e. STEPwise approach to NCD risk factor surveillance consisting of three steps viz. questionnaire for behavioural risk factors, physical measurements and biochemical measurements. Results: In this study, 24.2% (95%, confidence interval [CI]: 20.1-28.2) of participants screened positive for HTN. The proportion of males who screened positive for HTN was 28.8% (95% CI: 22.6-35), whereas the proportion of females who screened positive for HTN was 19.6% (95% CI: 14.3-25). In this study, elderly (>60 years), male gender, daily tobacco use, greater waist circumference (male >90 cm and female >80 cm), and daily salt intake of more than 5 g were found to have higher odds of having HTN. Conclusion: The prevalence of undiagnosed HTN in the UHTC of AIIMS Raipur was quite high.
RESUMO
Background: As more recent implant biomaterials, Zirconia ceramic and glass or carbon fibre reinforced PEEK composites have been introduced. In this study, bone stress and deformation caused by titanium, carbon fiber-reinforced polyetheretherketone (CFRPEEK), and zirconia ceramic implants were compared. Materials and Methods: In this in vitro finite element analysis study, a geometric model of mandibular molar replaced with implant supported crown was generated. The study used an implant that was 5 mm diameter and 11.5 length. Three implant assemblies made of CFR- polyetheretherketone (PEEK), zirconium, and titanium were created using finite element analysis (FEM). On the implant's long axis, 150 N loads were applied both vertically and obliquely. ANSYS Workbench 18.0 and finite element software were used to compare the Von Mises stresses and deformation produced with a significance level of P < 0.05. Results: With no discernible differences, all three implant assemblies that is CFR-PEEK, titanium, and zirconia demonstrated similar stresses and deformation in bone. Conclusion: It was determined that zirconia and PEEK and reinforced with carban fibres (CFR-PEEK) can be used as titanium-free implant biomaterial substitutes.
RESUMO
Introduction: Acute surge in coronavirus disease-2019 (COVID)-associated mucormycosis (CAM) cases was reported during mid-May 2021, which was later declared an epidemic in various states of India including Bihar. Objective: We carried out a rapid investigation of CAM cases to describe the epidemiological and clinical profiles and find plausible predictors to guide the initiation of public health actions. Methods: A team of public health specialists contacted all the CAM cases reported to our hospital to collect relevant information using a case-investigation-form. In addition, the team visited the Flu Clinic and Ear, Nose, and Throat (ENT) outpatient department (OPD) to capture CAM cases on daily basis during the period of the acute surge of CAM cases. Results: About 88% of 130 CAM cases reported during the period of the acute surge were in the advanced stage of mucormycosis. The majority of the CAM cases were younger (less than 60 years) [76.2%], diabetics [65.4%], un-vaccinated [86.9%], and had used steroids for management of COVID-19 [64.6%]. Other findings of public health importance were summarized and possible public health actions were recommended for the prevention of outbreaks in future. Conclusion: Optimum management of diabetes including screening for each COVID case, rational use of steroids only when necessary, strict adherence to COVID appropriate behavior by health professionals as well as the public, increasing COVID vaccine coverage, CAM awareness, and setting up a CAM surveillance mechanism may be the key to prevent and control CAM outbreaks in future.
RESUMO
A new variant of coronavirus (2019-nCoV) causing acute respiratory distress in humans was identified for the first time in 2019, in Wuhan, China. One of the many complications of infection with this coronavirus is hypercoagulopathy, resulting in acute thrombosis; often leading to acute limb ischaemia. Herein, we report 20 cases of COVID-19 with peripheral arterial thrombosis involving either upper or lower limbs. Some patients underwent vascular procedures and most had to undergo amputation at some level. All the cases (n=20) were referred to us during the 8-month period June 2020 to March 2021. The most common age group was between 51 and 60 years, of whom 80% were males; all the patients had diabetes. The right lower limb was most affected (50%); 15 patients underwent embolectomy. Twenty-five per cent of patients presented with wet gangrene. One patient with upper limb thrombosis recovered after embolectomy and did not require any amputation. Eighty-five per cent of patients underwent some form of amputation and the mortality rate was 10%. Arterial thrombosis is one complication patients may develop during COVID-19 illness, which may affect the outcome. Patients with comorbid conditions like diabetes are at higher risk of developing arterial thrombosis during COVID-19 infection. Susceptibility to coagulopathy may continue even after patient discharge and it is important that both patients and treating physicians are aware of this limb-threatening complication and seek early medical attention.
Assuntos
Arteriopatias Oclusivas , COVID-19 , Doenças Vasculares Periféricas , Trombose , Amputação Cirúrgica , Arteriopatias Oclusivas/complicações , COVID-19/complicações , Feminino , Humanos , Isquemia/complicações , Isquemia/cirurgia , Masculino , Pessoa de Meia-Idade , Trombose/etiologia , Trombose/cirurgia , Resultado do TratamentoRESUMO
Chapati is an unleavened flat baked product and it is prepared using whole wheat flour. One of the problems with chapatis is that they stale rapidly during storage and therefore, they have to be consumed immediately after their preparation. With changing socio-economic conditions and lifestyles, there is an increasing demand for ready to eat chapatis. In the present study, to control staling, chapatis were prepared using whole wheat flours of four different varieties by incorporating additives such as surfactant and fat. The chapatis stored at room temperature for 24 h, 48 h, 72 h and 96 h were evaluated for their quality parameters such as moisture content, chemical properties, sensory attributes, microstructure and amylograph characteristics. The moisture, soluble starch and soluble amylose contents in control chapatis decreased steadily with storage time and at the end of 96 h, the decrease in moisture, soluble starch and soluble amylose contents in chapatis prepared from different varieties were 3-8%, 80-82% and 78-85%, respectively. However, these changes were found to be at a very lesser rate in chapatis prepared from doughs treated with glycerol monostearate (GMS) and fat compared to that of control. Decrease in amylograph paste viscosity was more in control chapatis during storage compared to that of treated chapatis. Scanning electron microscopic studies of chapatis stored up to 96 h revealed that starch granules were uniform in both GMS and fat treated chapatis, when compared to control chapatis. Sensory studies showed that overall quality scores for chapatis prepared from GMS and fat treated doughs did not show any significant differences on storage. Thus, the results suggested that incorporation of surfactant and fat in dough not only improved the overall quality attributes of chapatis but also controlled their staling, during their storage.
RESUMO
The legume pod-borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) (LPB), is an important insect pest of pigeon pea. Chemical pesticides are generally employed to manage this pest, but because of the soil residue issues and other environmental hazards associated with their use, biopesticides are also in demand. Another benign alternative is to use entomopathogenic nematodes (EPNs) to manage this vital pest. In the present study, the infectivity of ten native EPNs was evaluated against LPB by assessing their penetration and production in the LPB. The effectiveness of the promising EPNs against second-, third- and fourth-instar LPB larvae was also studied. Heterorhabditis sp. (Indian Agricultural Research Institute-Entomopathogenic Nematodes Rashid Pervez (IARI-EPN RP) 06) and Oscheius sp. (IARI-EPN RP 08) were found to be most pathogenic to LPB, resulting in about 100% mortality within 72 h, followed by Steinernema sp. (IARI-EPN RP 03 and 09). Oscheius sp. (IARI-EPN RP 04) was found to be the least pathogenic to LPB larva with 67% mortality. Maximum penetration was exhibited by Heterorhabditis sp. (IARI-EPN RP 06) followed by Oscheius sp. (IARI-EPN RP 08), whereas the lowest rate of penetration was exhibited by Oscheius sp. (IARI-EPN RP 01). The highest rate of production was observed with Oscheius sp. (IARI-EPN RP 08), followed by Oscheius sp. (IARI-EPN RP 04 and 10). Among the tested instars of the LPB larvae, second-instar larvae were more susceptible to EPNs, followed by third- and fourth-instar larvae. The results indicate that Heterorhabditis sp. (IARI-EPN RP 06) and Oscheius sp. (IARI-EPN RP 08) have a good potential to the manage LPB.
Assuntos
Cajanus , Mariposas , Controle Biológico de Vetores , Rabditídios , Animais , Mariposas/parasitologia , Mariposas/patogenicidadeRESUMO
Optimal medical infrastructure utilization became a high priority for Governments worldwide during the COVID-19 pandemic. Special attention is drawn to both the import and local manufacture of medical oxygen gas to ensure its uninterrupted supply to designated COVID-hospitals identified by the local administration. The paper apprises on the administrative and regulatory orders to control the supply and transportation of medical oxygen gas by examining its implementation in India in general and the State of Andhra Pradesh in particular. The paper enhances understanding of the working of governmental administrative systems amidst the emergency. The observations and findings from the research work can be vital inputs to Governmental institutions, regulatory bodies, the industry, and various other stakeholders dealing with medical oxygen gas so that policy and process flow can be improvised.
RESUMO
This work investigates the Musa Paradisiaca plant and its tepal extracts. The research findings show that the tepal extracts of M. Paradisiaca contain high phytochemical activity. Hence we can conclude that these plants have a number of beneficial properties. Phytochemical analysis concludes that the plant is rich in flavonoids, phenolic compounds, tannins, terpenoids, and phytosterol. In the current work, silver nanoparticles (AgNPs) have revealed the antioxidant properties of M. Paradisiaca. The results show that the methanolic extracts of these tepals exhibit antioxidant potential and are also sources of natural antioxidant compounds, though comparatively, AgNPs have shown the best antioxidant activity. This work investigates the link between the ethnopharmacological statements and the bioactive constituents found in M. Paradisiaca toward all probable markers for cervical cancer via in vivo studies and molecular docking, to form a pharmacophore setting for the active target. However, most of the mechanisms of action of herbal medicines are not in total agreement, and the information collected from their traditional remedies over the years must not be neglected. Hence, it is sensible to investigate the options available in herbal medicine for cancer progression. Biosynthesised AgNPs are principally spherical and nanosized. It was also found that tepalmediated AgNPs exhibit excellent antimicrobial efficacy against tested human pathogens. This green method can be used as a better alternative source than the chemical fabrication of nanomaterials and the biosynthesised nanoparticles can be used in antibacterial medicines. The methanolictepal extract of M. Paradisiaca with AgNPs displayed proficient antidiabetic properties in the diabetes rat model and so could have a possible development for medical use in the future.
Assuntos
Antibacterianos , Nanopartículas Metálicas , Musa , Extratos Vegetais , Animais , Antibacterianos/farmacologia , Humanos , Hipoglicemiantes/farmacologia , Simulação de Acoplamento Molecular , Musa/química , Extratos Vegetais/farmacologia , Ratos , PrataRESUMO
RESULTS: AMH results were pooled and a table with 2.5 and 97.5 percentiles for each age group constructed. Based on Youden index, the optimal cut off for low responders (0-3 eggs), was 5.5 pmol/l (87% sensitivity, 55% specificity) and for high responders (>15 eggs) 15.6 pmol/l (78% sensitivity, 57% specificity). AMH correlated with number of eggs collected (r = 0.48) and clinical pregnancies (r = 0.14), (p < .0001). CONCLUSIONS: The table of AMH levels measured using the Access 2 fully automated immunoassay system according to age may be used as a reference and cutoff levels for high and poor responders are clearly defined to help tailor controlled ovarian stimulation, maximizing efficiency and ensuring patient safety. The use of a random access automated immunoassay system means that blood sampled on arrival can produce an AMH result in 40 mins by the time the subject enters the doctor's clinic together with other relevant endocrine markers.
Assuntos
Hormônio Antimülleriano/sangue , Análise Química do Sangue , Adulto , Envelhecimento/fisiologia , Hormônio Antimülleriano/análise , Hormônio Antimülleriano/normas , Automação Laboratorial , Análise Química do Sangue/instrumentação , Análise Química do Sangue/métodos , Análise Química do Sangue/normas , Feminino , Fertilização in vitro/métodos , Hormônio Foliculoestimulante/sangue , Humanos , Imunoensaio/instrumentação , Imunoensaio/métodos , Imunoensaio/normas , Pessoa de Meia-Idade , Recuperação de Oócitos/métodos , Recuperação de Oócitos/normas , Reserva Ovariana/fisiologia , Indução da Ovulação/métodos , Indução da Ovulação/normas , Gravidez , Taxa de Gravidez , Valores de Referência , Estudos Retrospectivos , Adulto JovemRESUMO
Statins are potent inhibitors of the mevalonate/cholesterol biosynthetic pathway and are widely prescribed for the prevention of cardiovascular diseases. Here, we carried out a comprehensive analysis of the effects of three statins, simvastatin, atorvastatin, and lovastatin, on six different cancer cell lines that include a P-glycoprotein-expressing, multidrug resistant variant of an ovarian cancer cell line. Incubation of all cancer cell lines with statins resulted in suppression of cell proliferation without inducing apoptotic cell death. The cell proliferation arrest could be reversed upon transfer of cells to statin-free growth media as well as by the supplementation of the growth media with mevalonate. Further analysis suggested that statins induced cell cycle arrest at G0/G1 phase in four cancer cell lines and the loss of c-Myc protein in three cancer cell lines. The c-Myc expression and the progression of cell division cycle were restored upon the addition of mevalonate to the culture media containing statins. Finally, cells incubated with statins contained an increased level of phosphorylated histone H2AX, an observation previously correlated to cellular senescence. Together, these data demonstrate that statins inhibit the mevalonate pathway which is tightly coupled to oxidative branch of the pentose phosphate pathway, c-Myc expression, cell division cycle progression, and cellular senescence. Implications of these observations in the application of statins as cancer therapeutics are discussed.
Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Atorvastatina/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fluvastatina/farmacologia , Humanos , Lovastatina/farmacologia , Ácido Mevalônico/metabolismo , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myc/biossíntese , Sinvastatina/farmacologiaRESUMO
As per the voices in the precision manufacturing industries, the machining of brittle materials such as glass and diamond is intricate owing to their thermo-mechanical properties. Machining of the brittle material with a localized heating method produced softness in the work material during the operation, resulting in microcracks and voids on the finished surface due to thermal stresses. Such pressing issues are solved by dry machining with bulk heating. The objective of the present research is to develop a sophisticated lab-made portable multipurpose heating setup for enabling various potent applications such as machining, elevated temperature scratch and indentation tests, and grinding, among other things, on hard and brittle materials. The mentioned process is done by softening the material with preheating of the samples. The overall dimensions of the developed setup are 105 × 150 × 53 mm3. This setup has been evaluated at different temperatures of the 45S5 bioglass sample surface up to 426 °C and is capable of holding and heating the samples.
RESUMO
Carcinogens play a key role in cancer initiation. Conventional theories support the concept of genetic changes inducing tumorigenesis through proteomics and metabolomics which lead to cancer development. Current research provides evidence that metabolic genes may be altered long before mutation of tumour suppressor genes, strongly suggesting that metabolic changes may be preceding the changes seen at a genetic level. Since cancer has long been known to occur through gene regulation, an impaired cellular respiration without utilizing mitochondrial function has been an area of active interest. We hypothesize the activity of carcinogens as electron acceptors to disrupt the normal glycolysis cycle happening in a cell by acting as positive ligands. The continuous restoration of NAD+ to cytosol by oxidation of NADH with carcinogen as electron acceptor creates a metabolic pathway to assist in the carcinogenic process. This metabolic pathway continues through an adaptive process, supplemented by pyruvate converting to lactate providing a constant pool of NAD+ to continue the glycolytic pathway. We also hypothesize that carcinogenesis occurs as a precursor to metabolic stress which may promote altered genetic and protein expression causing aberrant epigenetic and cell signaling pathways.
Assuntos
Carcinógenos , Elétrons , Carcinogênese , Carcinógenos/toxicidade , Glicólise , Humanos , OxirreduçãoRESUMO
INTRODUCTION: Brassica oleracea var acephala was studied for preliminary phytochemical screening. The results showed that the ethanolic crude extract of the leaf contain high phytochemical activity hence B.oleracea var acephala is rich in flavonoids, phenolic compounds, carbohydrates and phytosterols. MATERIALS AND METHODS: The ethanolic extract was used to synthesise copper nanoparticles. The copper nanoparticles were successfully synthesised from copper sulphate solution which was identified by the colour change from dark green colour of the extract. Thus the B.oleracea var acephala is a good source to synthesis copper nanoparticles. The synthesised copper nanoparticles were characterised using Scanning Electron Microscope (SEM) analysis. The SEM image displayed the high-density nanoparticles synthesised by leaf extracts and that the nanoparticles were crystals in shape. RESULTS: The copper nanoparticles (CNP) bind to the leaf extract. B.oleracea var acephala also has shown the antimicrobial and antioxidant activity. A comparative study was done between ethanolic its crude extract and nanoparticles. Both extracts exhibited zone of inhibition and better antioxidant potential but the CuNPs shows major zone of inhibition and showed more antioxidant activity. Anticancer activity of B.oleracea var acephala against Cervical HeLa cell line was confirmed using ethanolic crude extract and CNP. The results showed that HeLa cells proliferation was inhibited with increasing concentration of ethanolic crude extract and copper nanoparticles. From the results, it was seen that percentage viability of the cancer cells decreased with increased concentration of the samples whereas cytotoxicity against HeLa cell lines increased with the increased concentration of the samples. CONCLUSION: Thus B.oleracea var acephala possesses anticancer activity against HeLa cell lines.
Assuntos
Antibacterianos , Antineoplásicos Fitogênicos/farmacologia , Brassica , Nanopartículas , Extratos Vegetais , Antibacterianos/farmacologia , Brassica/química , Cobre , Células HeLa , Humanos , Extratos Vegetais/farmacologia , Folhas de Planta/químicaAssuntos
COVID-19/complicações , COVID-19/diagnóstico , Catepsinas/metabolismo , Furina/metabolismo , Neoplasias Bucais/complicações , Doenças Periodontais/complicações , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/epidemiologia , Membrana Celular/metabolismo , Biologia Computacional , Humanos , Modelos Teóricos , Neoplasias Bucais/epidemiologia , Doenças Periodontais/epidemiologia , Distanciamento Físico , Ligação Proteica , Domínios Proteicos , Fatores de RiscoRESUMO
INTRODUCTION: Laparoscopic repair is now the treatment of choice for most cases of ventral/incisional hernia. Although the technique has undergone many refinements, there is no standard technique for difficult or complicated hernias. AIM: The aim of this study was to show the different innovative methods used to treat difficult ventral hernia through hybrid techniques. MATERIALS AND METHODS: A total of 75 (n = 75) patients underwent Laparoscopic Ventral Hernia Hybrid Mesh Repair (LVHHMR) by our surgical unit between January 2014 and December 2016. Three different techniques of repairing the defects were used. Mesh fixation time, post-operative pain score (visual analogue score) and follow-up for pain and recurrence (at 6 months, 12 months and 24 months) were recorded and analysed. RESULTS: Out of 75 patients (20 men and 55 women), the median age was 45 years and body mass index of the patients was 25-35. Types of hernias operated were paraumbilical hernias, incisional and recurrent hernias. The techniques used were (1) laparoscopic adhesiolysis, open sac excision with closure of defect and laparoscopic mesh placement, (2) laparoscopic adhesiolysis, omphalectomy with closure of defect and laparoscopic mesh placement and (3) open adhesiolysis, sac excision with closure of defect and laparoscopic mesh placement. Five patients required analgesics for 48 h. No patients complained of pain at follow-ups (1 month, 6 months, 12 months and 24 months). Mean hospital stay postoperatively was 2-3 days. CONCLUSION: LVHHMR is safe and feasible approach for complicated/difficult ventral hernias. However, further larger studies are required to establish these methods as gold standard.
RESUMO
OBJECTIVE: The diversity of tissue structure in histopathological images makes feature extraction for classification a challenging task. Dictionary learning within a sparse representation-based classification (SRC) framework has been shown to be successful for feature discovery. However, there exist stiff practical challenges: 1) computational complexity of SRC can be onerous in the decision stage since it involves solving a sparsity constrained optimization problem and often over a large number of image patches; and 2) images from distinct classes continue to share several geometric features. We propose a novel analysis-synthesis model learning with shared features algorithm (ALSF) for classifying such images more effectively. METHODS: In the ALSF, a joint analysis and synthesis learning model is introduced to learn the classifier and the feature extractor at the same time. Unlike SRC, no explicit optimization is needed in the inference phase leading to much reduced computation. Crucially, we introduce the learning of a low-rank shared dictionary and a shared analysis operator, which more accurately represents both similarities and differences in histopathological images from distinct classes. We also develop an extension of ALSF with a sparsity constraint, whose presence or absence facilitates a cost-performance tradeoff. RESULTS: The ALSF is evaluated on three challenging and well-known datasets: 1) spleen tissue images; 2) brain tumor images; and 3) breast cancer tissue dataset, provided by different organizations. CONCLUSION: Experimental results demonstrate both complexity and performance benefits of the ALSF over state-of-the-art alternatives. SIGNIFICANCE: Modeling shared features with appropriate quantitative constraints lead to significantly improved classification in histopathology.