Rajesh Varma
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Convolutional modelling of epidemics
No full textTraditional deterministic modeling of epidemics is usually based on a linear system of differential equations in which compartment transitions are proportional to their population, implicitly assuming an exponential process for leaving a compartment as happens in radioactive decay. Nonetheless, this assumption is quite unrealistic since it permits a class transition such as the passage from illness to recovery that does not depend on the time an individual got infected. This trouble significantly affects the time evolution of epidemy computed by these models. This paper describes a new deterministic epidemic model in which transitions among different population classes are described by a convolutional law connecting the input and output fluxes of each class. The new model guarantees that class changes always take place according to a realistic timing, which is defined by the impulse response function of that transition, avoiding model output fluxes by the exponential decay typical of previous models. The model contains five population compartments and can take into consideration healthy carriers and recovered-to-susceptible transition. The paper provides a complete mathematical description of the convolutional model and presents three sets of simulations that show its performance. A comparison with predictions of the SIR model is given. Outcomes of simulation of the COVID-19 pandemic are discussed which predicts the truly observed time changes of the dynamic case-fatality rate. The new model foresees the possibility of successive epidemic waves as well as the asymptotic instauration of a quasi-stationary regime of lower infection circulation that prevents a definite stopping of the epidemy. We show the existence of a quadrature function that formally solves the system of equations of the convolutive and the SIR models and whose asymptotic limit roughly matches the epidemic basic reproduction number.</p
Cephalometric evaluation and comparison of upper pharyngeal airway space in cleft lip and cleft palate patients treated with maxillary advancement and camouflage
No full textIntroduction: Pharyngeal airway space has become an important criterion for diagnosis and treatment planning and this has led to a paradigm shift towards soft tissue evaluation for orthodontic diagnosis and treatment planning, The aims and objectives of the study were to evaluate and compare upper pharyngeal airway space in Cleft Lip & Cleft Palate patients who underwent orthodontic treatment under different treatment modalities like Camouflage treatment & Maxillary Advancement.Methods: This is a retrospective cephalometric study in which 20 Pre-treatment Cephalograms and 20 Post-treatment Cephalograms of Cleft Lip and Palate patients were taken. Orthodontic treatment involving Camouflage therapy and Maxillary Advancement were studied in each respective group. The Cephalogram was traced on Matt acetate paper and the pharyngeal airway space was measured using the McNamara analysis method.Results: Statistically significant difference was observed in the Pre-treatment and Post-treatment mean values in both groups, where the Post-treatment mean was higher than the Pre-treatment means in both groups. A highly significant mean was noted in the Cleft Surgical group as compared to the Camouflage (xiii) group, where, the post-treatment upper airway mean was higher in the Cleft Surgical group than the Cleft Camouflage group.Conclusion: There is a significant increase in upper pharyngeal airway space in patients with CLCP treated with Maxillary Advancement and Camouflage modality. The significance is comparatively more in the Maxillary Advancement group than in the Camouflage group.</p
Effect of Water and Soil Contamination by Heavy Metals in Lettuce (Lactuca sativa), Cabbage (Brassica oleracea var. capitate), and Turnip (Brassica napus L.) at Different Stage
No full textEnvironmental pollution with heavy metals is very harmful to the human body and other life forms, even in low concentrations, as there is no effective removal mechanism. Urban agriculture utilizes this contaminated land for the cultivation of vegetable crops to facilitate their food security and entry of toxic heavy metals into the food chain. The objective of this study was to evaluate the impact of contaminated soil and water with heavy metals on the quality of vegetable crops at different growth ages. Microwave Plasma Atomic Emission Spectrometry (MP-AES) was used to determine the concentration of these heavy metals. The concentration of heavy metals (Fe, Mn, Zn, Cu, Co, Ni, Pb, and Cr) in contaminated soil was found to be 39434.9±30.0, 3183.7±43.5, 222.0±10.2, 22.28±2.5, 0.057±0.00, 5.8±0.03, 72.72±0.01, 148.6±15 mg/kg, respectively. In addition, the mean concentration of Fe, Mn, Zn, Cu, Co, Ni, and Cr in wastewater was found to be 5.2±0.5, 0.8±0.08, 0.72±0.01, 1.05±0.03, 0.01±0.00, 0.2±00, 0.72±0.01 and 0.14±0.02, respectively. The relative abundance of heavy metal in soil, water and vegetable samples were in the following order: Fe >Mn >Zn > Cr > Pb> Cu> Ni> Co, Fe > Cu > Mn >Zn =Pb> Ni > Cr > Co and Fe >Mn >Zn > Pb > Cu> Cr > Ni> Co, respectively, and the accumulation of heavy metals in three month growth. All lettuce, cabbage, and turnip vegetables grew faster than two months. Both two and three months of age, the accumulation of heavy metals in turnips > lettuce > cabbage. Most of the soil, water, and vegetable samples exceeded the permissible limit of heavy metals prescribed by the World Health Organization (WHO) standards.</p
Habitats and Characteristics of Sardina pilchardus, off the Moroccan Atlantic coast
No full textThis paper is an overview of the main characteristics of Sardina on the Moroccan Atlantic coast. Sardine occupies an important place in the socio-economic context of Morocco and is the main species exploited on Moroccan coasts. It is the most important species in terms of catches and biomass. The small pelagic stocks in the area are exceptional wealth and as many opportunities in an international context, marked both by the scarcity of the resource and the need to make the sea c contribute more to food security and economic growth. The aim of this work is the study some features of S. pilchardus in the Moroccan waters.</p
The mining of cobalt must meet the highest environmental and health standards
No full textIn an effort to combat climate change there is a major rush to eliminate the use of fossil fuels. However, this must be done in an orderly process to avoid stressing an already overstressed planet. The push for electric cars and lithium batteries requires intensive mining to extract the heavy metals needed to meet increasing global demands. This is in addition to the already staggering increase in the worldwide usage of digital devices and electronics that require the same metals. Heavy metals such as nickel, chromium, iron, zinc, manganese and cobalt, at very low concentrations, are all essential to the growth and development of plants [1-3]. </p
Flowable placental connective tissue matrices for tendon repair: A review
No full textTendon injuries are associated with considerable pain and disability. Owing to the hypovascularity and hypocellularity of the tissue, natural tendon healing is slow and ineffective. Traditional conservative and surgical treatment options fail to address the underlying pathology. As a result, the healed tendon is mechanically incompetent and prone to degeneration and rupture. Therefore, new biological methods have been suggested to enhance tendon repair and regeneration. Flowable Placental Connective Tissue Matrices (FP-CTMs) represent a promising means to promote tendon healing. Like non-flowable placental scaffolds, FP-CTMs possess the innate healing properties of the placenta and provide structural and biochemical extracellular matrix components. Unlike their non-flowable counterparts, FP-CTMs have the added benefits of minimal invasiveness and the capacity to fill irregular spaces. FP-CTMs can enhance tendon repair by providing a three-dimensional extracellular matrix for cellular attachment and proliferation while decreasing inflammation and limiting adhesion formation. The present report reviews tendon biology, pathology, healing, and current treatment modalities, followed by a comprehensive literature review, evaluating the clinical application of FP-CTMs for tendon repair. Recent research suggests that the use of FP-CTMs in tendon repair is safe and efficacious and further indicates that FP-CTMs can modulate the tendon repair environment and improve clinical outcomes. However, the existing clinical evidence is limited to retrospective case series with no control group. Therefore, additional work must be performed to better understand the clinical applications and therapeutic benefits of FP-CTM in tendon repair compared with conventional treatments.</p
Theta-Burst Stimulation over the pre-Supplementary Motor Area in Schizophrenia and comorbid substance use disorder: Preliminary clinical data
No full textSchizophrenia (SZ) is a debilitating disorder, which tremendously impacts the psychological, social, and financial aspects of a patient’s life. Frequently, SZ patients present with poor insight, which can even worsen the symptomatology. Antipsychotic medications frequently result in suboptimal outcomes, especially the ones concerning negative and cognitive symptoms. Accordingly, new therapeutic options are warranted. Transcranial Magnetic Stimulation (TMS) has been adopted in SZ with promising results. Continuous Theta burst stimulation (cTBS) is a particular brief and effective form of TMS. It has been successfully applied in patients with poor cognitive control (e.g., gambling disorder patients) targeting the pre-Supplementary Motor Area (pre-SMA). Given that poor cognitive control has been regarded as a core deficit in SZ, 11 patients with SZ were included in this study and treated with cTBS for a total of 10 sessions during a two-week period. Patients were divided into two groups: patients with a diagnosis of SZ in comorbidity with Substance Use Disorder (SZ + SUD) vs SZ. Patients were evaluated before and after treatment, assessing executive functions, awareness, and nicotine craving. Within-group comparisons showed a significant reduction in the Scale to assess Unawareness in Mental Disorders (SUMD) scores (p < 0.05) and in the test of Fagerstrom (to assess nicotine dependence) scores (p < 0.001) before and after treatment in the SZ + SUD group. These results showed the efficacy of cTBS for craving reduction as well as in improving awareness of the illness and of treatment. This can be considered a remarkable result since better insight has been previously associated with an improved quality of life in SZ. </p
Covid-19 and severe OAT syndrome with dramatic recovery
No full textWe describe a young man of 37 years with a transient but marked Oligoasthenoteratozoospermia (OAT) syndrome due to severe covid infection with the perfect recovery of semen parameters along with recovery of general health. Setting district general hospital: Intervention none.We review the role of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2 virus), the role of Angiotensin-Converting Enzyme 2 (ACE-2), Angiotensin 1-7 (Ang 1-7) and propose that it is potentially involved in a cause and effect mechanism of injury.</p
Erythromelalgia: Definition, clinical contexts, differential diagnosis, and therapy. Single case and literature update
No full textClinical publications on this morbid condition report as many as 16 different Nav1 7 channel substitutions. They also report more than 40 pharmacological treatments, including agents with sodium channel blocking but nonspecific activity (mexiletine, lidocaine, carbamazepine), anti-neuropathic drugs (gabapentinoids and antidepressants), antidepressant drugs with efficacy on migraines (amitriptyline) vasoactive drugs for the management of hypertension, and analgesics (opioids and ketamine). Current research fails to address all patients’ clinical needs, although it recently suggests new genetic hypotheses yet to be tested and the central importance of genetic counseling, to inform patients and their families about the severity, likely course of symptoms, and risk of complications, and in some cases to guide clinical management. Current findings and the significant morbidity associated with the condition, even in light of the single case presented, highlight the need for mechanism-based therapies to improve clinical outcomes.</p
Antimicrobial activities and phytochemical profile of the leaf extracts of Barringtonia racemosa L. (Putat) against selected pathogens: An ethnomedicinal plant species
No full textBarringtonia racemosa L. (Putat) was mostly utilized as a treatment for wound infections and other types of skin diseases locally. The leaves of B. racemosa are traditionally used to treat high blood pressure and as a depurative. This study aimed to assess the antimicrobial activities and phytochemical profile of the leaf extracts of Barringtonia racemosa L. (Putat) against selected pathogens. The ethanolic extracts of the leaves were explicitly prepared and applied to two Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus), whereas the Gram-negative bacteria (Escherichia coli) used the disc diffusion method based on the standard procedure. Moreover, among the test microorganisms, only the Gram-positive bacteria were sensitive to the ethanolic extracts of Barringtonia racemosa L. with the diameter of zone of inhibition ranging from 13.81±0.96 mm to 14.85±0.57 mm. The findings of this study suggested that the tribes could explicitly continue utilizing this ethnomedicinal plant as a source of treatment. Thus, the ethanol extracts of the leaves of B. racemosa were found to be effective against several pathogens used in this study, which certainly highlights the potential extremity of herbal drugs and their possible use as local medicine. Hence, there has been a continuing search for new and more potent antibiotics.</p