A Framework for Estimating Mold Performance Using Experimental and Numerical Analysis of Injection Mold Tooling Prototypes

Additive Manufacturing (AM), 3D printing, rapid prototyping, or rapid tooling refer to a range of technologies that are capable of translating virtual CAD model data into physical model. It is executed in growing number of applications nowadays. A wide range of materials are currently being used to produce consumer products and production tools. AM has brought in revolutionary changes in traditional manufacturing practices. Yet, there are certain drawbacks that hinder its advancement at mass manufacturing. High cost associated with AM is one of them. Using 3D printed tooling can provide long-time cost effectiveness and better product quality. Additively manufactured injection molds can increase the cooling performance, reduce production cycle time, and improve surface finish and part quality of the final plastic product. Yet, manufacturers are still not using the printed molds for industrial mass production. Numerical analysis can provide approximation of such improved performance, but, factual experimental results are necessary to satisfy performance criteria of molds to justify the large investment into tooling for existing industries. In this research work, a desktop injection molding machine is used to evaluate performance of 3D printed molds to develop a cost and performance analysis tool. It serves as a baseline to predict the performance of molds in real-time mass manufacturing of consumer products. The analysis describes how appropriate the estimation can be from any simulation study of molds, how much the scaling down of tool and molding system can affect the prediction of actual performance, what correction factors can be used for better approximation of performance matrices. Several “scaled down” prototypes of injection molds have been used. They have design variations as: with or without cooling system, conformal or straight cooling channels, solid or lattice matrix, and metal or tough resin as the mold material. The molds are printed in in-house printing machines and can also be printed online with limited charges. This also provides an excellent demonstration of using inexpensive material and manufacturing process, such as resin to estimate the performance of highly expensive 3D printed stainless steel molds. The work encompasses a framework to reduce overall cost of implementing AM, by lowering time and monetary expenses during the research and development, and prototyping phases

Tribal Formulations for Treatment of Pain: A Study of the Bede Community Traditional Medicinal Practitioners of Porabari Village in Dhaka District, Bangladesh

The Bedes form one of the largest tribal or indigenous communities in Bangladesh and are popularly known as the boat people or water gypsies because of their preference for living in boats. They travel almost throughout the whole year by boats on the numerous waterways of Bangladesh and earn their livelihood by selling sundry items, performing jugglery acts, catching snakes, and treating village people by the various riversides with their traditional medicinal formulations. Life is hard for the community, and both men and women toil day long. As a result of their strenuous lifestyle, they suffer from various types of pain, and have developed an assortment of formulations for treatment of pain in different parts of the body. Pain is the most common reason for physician consultation in all parts of the world including Bangladesh. Although a number of drugs are available to treat pain, including non-steroidal, steroidal, and narcotic drugs, such drugs usually have side-effects like causing bleeding in the stomach over prolonged use (as in the case of rheumatic pain), or can be addictive. Moreover, pain arising from causes like rheumatism has no proper treatment in allopathic medicine. It was the objective of the present study to document the formulations used by the Bede traditional practitioners for pain treatment, for they claim to have used these formulations over centuries with success. Surveys were conducted among a large Bede community, who reside in boats on the Bangshi River by Porabari village of Savar area in Dhaka district of Bangladesh. Interviews of 30 traditional practitioners were conducted with the help of a semi-structured questionnaire and the guided field-walk method. It was observed that the Bede practitioners used 53 formulations for treatment of various types of pain, the main ingredient of all formulations being medicinal plants. Out of the 53 formulations, 25 were for treatment of rheumatic pain, either exclusively, or along with other types of body pain. A total of 65 plants belonging to 39 families were used in the formulations. The Fabaceae family provided 7 plants followed by the Solanaceae family with 4 plants. 47 out of the 53 formulations were used topically, 5 formulations were orally administered, and 1 formulation had both topical and oral uses. 8 formulations for treatment of rheumatic pain contained Calotropis gigantea, suggesting that the plant has strong potential for further scientific studies leading to discovery of novel efficacious compounds for rheumatic pain treatment

Medicinal formulations of a Kanda tribal healer – a tribe on the verge of disappearance in Bangladesh

The Kanda tribe is one of the lesser known small tribes of Bangladesh with an estimated population of about 1700 people (according to them), and on the verge of extinction as a separate entity. To some extent, they have assimilated with the surrounding mainstream Bengali-speaking population, but they still maintain their cultural practices including traditional medicinal practices, for which they have their own tribal healers. Nothing at all has been documented thus far about their traditional medicinal practices and formulations, which are on the verge of disappearance. The Kanda tribe can be found only in scattered tea gardens of Sreemangal in Sylhet district of Bangladesh; dispersion of the tribe into small separated communities isalso contributing to the fast losing of traditional medicinal practices. The objective of the present study was to conduct an ethnomedicinal survey among the traditional healers of the Kanda tribe (in fact, only one such healer was found after extensive searches). Information was collected from the healer with the help of a semi-structured questionnaire and the guided field-walk method. A total of 24 formulations were obtained from the healer containing 34 plants including two plants, which could not beidentified. Besides medicinal plants, the Kanda healer also used the body hairs of the Asiatic black bear (Ursus thibetanus) and bats (Pteropus giganteus giganteus) in one of his formulation for treatment of fever with shivering. The ailments treated by the Kanda healer were fairly common ailments like cuts and wounds, skin diseases, helminthiasis, fever,  respiratory problems (coughs, asthma), gastrointestinal disorders (stomach pain, constipation, diarrhea), burning sensations during urination, various types of pain (headache, body ache, toothache, ear ache), conjunctivitis, poisonous snake, insect or reptile bites, jaundice, andbone fractures. A number of important drugs in allopathic medicine like quinine, artemisinin, and morphine (to name only a few) have been discovered from observing indigenous medicinal practices. From that view point, the formulations used by the Kanda healer merit scientific studies for their potential in the discovery of cheap and effective new drugs. Scientific validation of the medicinal formulations of the Kanda healer can also be effective for treatment of ailments among this tribe, which does not have or does not want to have any contact with modern medicine

Survey and scientific evaluation of medicinal plants used by the Pahan and Teli tribal communities of Natore district, Bangladesh

The Pahans and the Telis are two of the smallest indigenous communities in Bangladesh. The Pahans, numbering about 14,000 people are widely scattered in several northern districts of the country, while the Telis are such a small community that nothing has been reported on their numbers and lifestyle. Both tribes are on the verge of disappearance. One each of the Pahan and the Teli community was located after much search in two adjoining villages of Natore district, Bangladesh. Since the tribes were found to still depend on their traditional medicinal practitioners for treatment of ailments, it was the objective of the present study to document their traditional usage of medicinal plants and to evaluate such plants against modern research-based pharmacological activity studies on these plants. Interviews were conducted of the practitioners of the Pahan and Teli community of Natore district with the help of a semi-structured questionnaire and using the guided field-walk method. Plant specimens aspointed out by the practitioners were collected and pressed on the field and identification completed at the Bangladesh National Herbarium. The Pahan tribal practitioners used 13 plants distributed into 9 families for treatment of 14 different ailments. The Teli tribal practitioner used 15 plants divided into 14 families for treatment of 17 different ailments. Eight out of the thirteen plants used by the Pahan tribal practitioner (61.5%) had reported relevant pharmacological activities in the scientific literature, while six out of the fifteen plants used by the Teli tribal practitioners (40%) had such relevant pharmacological activities in accordance with their usage. The medicinal plants used by the Pahans and Telis warrant further scientific studies toward discovery of lead compounds and efficacious drugs and the documentation and protection of the traditional medical knowledge held by these tribes

Natural Splice Variant of MHC Class I Cytoplasmic Tail Enhances Dendritic Cell-Induced CD8+ T-Cell Responses and Boosts Anti-Tumor Immunity

Dendritic cell (DC)-mediated presentation of MHC class I (MHC-I)/peptide complexes is a crucial first step in the priming of CTL responses, and the cytoplasmic tail of MHC-I plays an important role in modulating this process. Several species express a splice variant of the MHC-I tail that deletes exon 7-encoding amino acids (Δ7), including a conserved serine phosphorylation site. Previously, it has been shown that Δ7 MHC-I molecules demonstrate extended DC surface half-lives, and that mice expressing Δ7-Kb generate significantly augmented CTL responses to viral challenge. Herein, we show that Δ7-Db-expressing DCs stimulated significantly more proliferation and much higher cytokine secretion by melanoma antigen-specific (Pmel-1) T cells. Moreover, in combination with adoptive Pmel-1 T-cell transfer, Δ7-Db DCs were superior to WT-Db DCs at stimulating anti-tumor responses against established B16 melanoma tumors, significantly extending mouse survival. Human DCs engineered to express Δ7-HLA-A*0201 showed similarly enhanced CTL stimulatory capacity. Further studies demonstrated impaired lateral membrane movement and clustering of human Δ7-MHC-I/peptide complexes, resulting in significantly increased bioavailability of MHC-I/peptide complexes for specific CD8+ T cells. Collectively, these data suggest that targeting exon 7-encoded MHC-I cytoplasmic determinants in DC vaccines has the potential to increase CD8+ T-cell stimulatory capacity and substantially improve their clinical efficacy

Molecular epidemiology of hcv among health care workers of khyber pakhtunkhwa

<p>Abstract</p> <p>Background</p> <p>Studies of the molecular epidemiology and risk factors for hepatitis C virus (HCV) in health care workers (HCWs) of Peshawar, Khyber Pakhtunkhwa region are scarce. Lack of awareness about the transmission of HCV and regular blood screening is contributing a great deal towards the spread of hepatitis C. This study is an attempt to investigate the prevalence of HCV and its possible association with both occupational and non-occupational risk factors among the HCWs of Peshawar.</p> <p>Results</p> <p>Blood samples of 824 HCWs, aged between 20-59 years were analysed for anti-HCV antibodies, HCV RNA and HCV genotypes by Immunochromatographic tests and PCR. All relevant information was obtained from the HCWs with the help of a questionnaire. The study revealed that 4.13% of the HCWs were positive for HCV antibodies, while HCV RNA was detected in 2.79% of the individuals. The most predominant HCV genotype was 3a and 2a.</p> <p>Conclusion</p> <p>A program for education about occupational risk factors and regular blood screening must be implemented in all healthcare setups of Khyber Pakhtunkhwa province in order to help reduce the burden of HCV infection.</p

Using trained dogs and organic semi-conducting sensors to identify asymptomatic and mild SARS-CoV-2 infections: an observational study

BACKGROUND: A rapid, accurate, non-invasive diagnostic screen is needed to identify people with SARS-CoV-2 infection. We investigated whether organic semi-conducting (OSC) sensors and trained dogs could distinguish between people infected with asymptomatic or mild symptoms, and uninfected individuals, and the impact of screening at ports-of-entry. METHODS: Odour samples were collected from adults, and SARS-CoV-2 infection status confirmed using RT-PCR. OSC sensors captured the volatile organic compound (VOC) profile of odour samples. Trained dogs were tested in a double-blind trial to determine their ability to detect differences in VOCs between infected and uninfected individuals, with sensitivity and specificity as the primary outcome. Mathematical modelling was used to investigate the impact of bio-detection dogs for screening. RESULTS: About, 3921 adults were enrolled in the study and odour samples collected from 1097 SARS-CoV-2 infected and 2031 uninfected individuals. OSC sensors were able to distinguish between SARS-CoV-2 infected individuals and uninfected, with sensitivity from 98% (95% CI 95–100) to 100% and specificity from 99% (95% CI 97–100) to 100%. Six dogs were able to distinguish between samples with sensitivity ranging from 82% (95% CI 76–87) to 94% (95% CI 89–98) and specificity ranging from 76% (95% CI 70–82) to 92% (95% CI 88–96). Mathematical modelling suggests that dog screening plus a confirmatory PCR test could detect up to 89% of SARS-CoV-2 infections, averting up to 2.2 times as much transmission compared to isolation of symptomatic individuals only. CONCLUSIONS: People infected with SARS-CoV-2, with asymptomatic or mild symptoms, have a distinct odour that can be identified by sensors and trained dogs with a high degree of accuracy. Odour-based diagnostics using sensors and/or dogs may prove a rapid and effective tool for screening large numbers of people. Trial Registration NCT04509713 (clinicaltrials.gov)

Hepatitis C virus to hepatocellular carcinoma

Hepatitis C virus causes acute and chronic hepatitis and can lead to permanent liver damage and hepatocellular carcinoma (HCC) in a significant number of patients via oxidative stress, insulin resistance (IR), fibrosis, liver cirrhosis and HCV induced steatosis. HCV induced steatosis and oxidative stress causes steato-hepatitis and these pathways lead to liver injury or HCC in chronic HCV infection. Steatosis and oxidative stress crosstalk play an important role in liver damage in HCV infection. This Review illustrates viral and host factors which induce Oxidative stress, steatosis and leads toward HCC. It also expresses Molecular cascade which leads oxidative stress and steatosis to HCC