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Topic Review
Surgical Management of Rectal Cancer
Successful oncologic resection in rectal cancer relies on the surgical tenants of wide local excision of the disease to establish clear margin status and resection of adequate lymph nodes for staging. The introduction of, and adherence to, complete total mesorectal excision, which is the resection of the total mesorectal envelope containing the local lymphatic drainage of the rectum, has contributed a large part to the improved operative outcomes and long-term survival for rectal cancer patients. Notably, total mesorectal excision has produced a notable reduction in rectal cancer recurrence by 30 to 40%.
  • 1.6K
  • 06 Apr 2022
Topic Review
Drug Delivery to Posterior Segment of Eye
The posterior segment of the eye comprises the back two-thirds of the eye, including the vitreous humor, the retina, the choroid and the optic nerve. Posterior Segment Eye Diseases (PSEDs) are then defined as the disorders that affect these tissues with the common main outcome of varying degrees of visual impartment and blindness. The most prevalent diseases are glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy (DR). This specialized organ is composed of various static and dynamic barriers that restrict drug delivery into the target site of action. Despite numerous efforts, effective intraocular drug delivery remains unresolved and, therefore, it is highly desirable to improve the current treatments of diseases affecting the posterior cavity. 
  • 1.6K
  • 06 Apr 2022
Topic Review
Synthesis of Ferrocenyl Phosphorhydrazone Dendrimers
The discovery of ferrocene is often associated with the rapid growth of organometallic chemistry. Dendrimers are highly branched macromolecules that can be functionalized at will at all levels of their structure. The functionalization of dendrimers with ferrocene derivatives can be carried out easily as terminal functions on the surface, but also at the core, or at one or several layers inside the structure. Depending on the desired location of the ferrocenes in the structure of phosphorhydrazone dendrimers, the ferrocenes should be functionalized differently. For the grafting to the surface, the ferrocene should bear a phenol group, suitable to react in substitution reactions with the P(S)Cl2 terminal groups of the dendrimers. To be used as core, the ferrocene should have two aldehyde functions, from which the synthesis of the dendrimer will be carried out. To be introduced in the branches, at all layers or within a single layer, the ferrocene should replace hydroxybenzaldehyde; thus, it should bear both a phenol and an aldehyde.
  • 1.6K
  • 06 Jun 2022
Topic Review
Aspiration Pneumonia and Dysphagia in the Elderly
Pneumonia in the elderly has been increasing on an annual basis. To a greater or lesser extent, aspiration is a major contributor to the development of pneumonia in the elderly. Antimicrobials alone are not sufficient for the treatment of pneumonia, and the condition may become intractable or even recur repeatedly. In addition, some patients with pneumonia may have no problems with eating, while others are unable to receive the necessary nutrition due to severe dysphagia. It has been found that pneumonia decreases both the muscle mass and strength of the swallowing and respiratory muscles, a condition named pneumonia-associated sarcopenia. This contributes to a pathophysiological time-axis of aspiration pneumonia and dysphagia in the elderly, in which silent aspiration leads to the development of pneumonia, and further to dysphagia, malnutrition, and low immunity. 
  • 1.6K
  • 09 Oct 2022
Topic Review
Non-Invasive Micro-Test Technology
Non-invasive micro-test technology (NMT) is a scientific research technology used for measuring physiological events of intact biological samples. NMT is used for research in many biological areas such as gene function, plant physiology, biomedical research, and environmental science. Most living things experience a constant exchange of ions and molecules with their surroundings as a result of biological processes. NMT uses specialized flux sensors, derived from microelectrodes, to measure this dynamic ion/molecule activity called flux around an intact sample. These fluxes reveal information about physiological phenomena. Each NMT flux sensor is selective or specific for a particular ion/molecule of choice. Some of the more commonly published ion/molecule flux sensors are those that are commercially available, such as Ca2+, H+, K+, Na+, Cl−, Mg2+, Cd2+, NH4+, NO3−, Pb2+, Cu2+, O2, H2O2, and IAA (indole-3-acetic acid). Some other flux sensors include glutamate, glucose, Zn2+, Hg2+, and more that have been designed by individual laboratories. NMT measures how much, how fast, and in what direction the chosen ions/molecules are moving. This is defined as diffusion flux, which is the amount of substance per unit area per unit time. The principle of how NMT measures flux was described in the 1990s by a few different laboratories; Lionel Jaffe at the Marine Biological Laboratory described the Vibrating Probe technique, and Ian Newman at the University of Tasmania described the MIFE™ technique. There are also technologies SERIS and SIET that use this principle.
  • 1.6K
  • 18 Oct 2022
Topic Review
Electrostatic Fluid Accelerator
An electrostatic fluid accelerator (EFA) is a device which pumps a fluid such as air without any moving parts. Instead of using rotating blades, as in a conventional propeller or in the turbine of an airbreathing jet engine, an EFA uses the Coulomb force from a high voltage electric field to accelerate electrically charged air molecules, a phenomenon studied in the academic discipline called electrohydrodynamics (EHD). Because air molecules are normally electrically neutral, not charged, the EFA has to create some charged molecules, or ions, first. Thus there are three basic steps in the fluid acceleration process: ionize air molecules, accelerate those charge carriers and, through ion-ion and ion-neutral collisions, push many more neutral molecules in a desired direction, and finally neutralize ions again to eliminate any net charge in the downstream flow. This principle is used for spacecraft propulsion in ion thrusters. The basic working principle has been understood for some time but only in recent years have seen developments in the design and manufacture of EFA devices that may allow them to find practical and economical applications, such as in micro-cooling of electronics components.
  • 1.6K
  • 31 Oct 2022
Topic Review
List of Minerals Approved by IMA (I)
This list includes those recognised minerals beginning with the letter I. The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go through the official naming procedure, although some minerals published previously have been either confirmed or discredited since that date. This list contains a mixture of mineral names that have been approved since 1959 and those mineral names believed to still refer to valid mineral species (these are called "grandfathered" species). The list is divided into groups: The data was exported from mindat.org on 29 April 2005; updated up to 'IMA2018'. The minerals are sorted by name, followed by the structural group (rruff.info/ima and ima-cnmnc by mineralienatlas.de, mainly) or chemical class (mindat.org and basics), the year of publication (if it's before of an IMA approval procedure), the IMA approval and the Nickel–Strunz code. The first link is to mindat.org, the second link is to webmineral.com, and the third is to the Handbook of Mineralogy (Mineralogical Society of America).
  • 1.6K
  • 07 Nov 2022
Topic Review
Ground Deicing of Aircraft
Ground deicing of aircraft is commonly performed in both commercial and general aviation. The fluids used in this operation are called deicing or anti-icing fluids. The initials ADF (Aircraft Deicing Fluid), ADAF (Aircraft Deicer and Anti-icer Fluid) or AAF (Aircraft Anti-icing Fluid) are commonly used.
  • 1.6K
  • 23 Nov 2022
Biography
Alfred Korzybski
Alfred Habdank Skarbek Korzybski (/kɔːrˈzɪbski, -ˈzɪp-, -ˈʒɪp-, kəˈʒɪpski/,[1][2] Polish: [ˈalfrɛt kɔˈʐɨpskʲi]; July 3, 1879 – March 1, 1950) was a Polish-American independent scholar who developed a field called general semantics, which he viewed as both distinct from, and more encompassing than, the field of semantics. He argued that human knowledge of the world is limit
  • 1.6K
  • 05 Dec 2022
Biography
Elise Harmon
Elise Frances Harmon (née Harmon; 3 September 1909 in Mount Enterprise, Texas – 6 March 1985 in Santa Clara County, California)[1] was an United States physicist, chemist, and influential contributor to the miniaturization of computers.[2][3][4][5][6][7][8][9][10][11] Research During World War II, she worked in the United States Naval Research Laboratory's Aircraft and Electrical Divi
  • 1.6K
  • 29 Dec 2022
Topic Review
The Orchids of Wetland Vegetation in Central Balkans
The orchid family (Orchidaceae) is one of the largest and most diverse families in the plant kingdom, with approximately 28,000 species and 880 genera. Because of their germination limitation, mycorrhizal specificity and pollinator specialization, orchids are particularly vulnerable to changes in ecosystem balance, especially changes in moisture content, light regime, nutrient availability and competition levels. Habitat changes or their complete destruction have led to the extinction or decline in abundance and distribution of many orchids and, consequently, many species are protected by laws and/or are included in Red Data Books. Therefore, knowledge of the habitats and ecological preferences of orchids is a prerequisite for their appropriate conservation.
  • 1.6K
  • 05 Jan 2023
Topic Review
Nanocellulose Functional Material
Nanocellulose is generally defined as cellulose particles or fibers with dimensions in the nanometer range. It can be derived from different cellulose sources, such as wood pulp, agricultural residues, or bacterial cultures, using various methods including mechanical treatment, enzymatic hydrolysis, or chemical processes.
  • 1.6K
  • 28 Jul 2023
Topic Review
The Effects of Dietary on Tumor Metabolism
The remodeled cancer cell metabolism affects the tumor microenvironment and promotes an immunosuppressive state by changing the levels of macro- and micronutrients and by releasing hormones and cytokines that recruit immunosuppressive immune cells. Novel dietary interventions such as amino acid restriction and periodic fasting mimicking diets can prevent or dampen the formation of an immunosuppressive microenvironment by acting systemically on the release of hormones and growth factors, inhibiting the release of proinflammatory cytokines, and remodeling the tumor vasculature and extracellular matrix.
  • 1.6K
  • 10 Aug 2023
Topic Review
Hot-Melt Adhesive Composition
Hot-melt adhesives (HMAs) are thermoplastic materials that can bond various substrates by solidifying rapidly upon cooling from the molten state, and their modification with organosilicon compounds can result in crosslinking behavior, characteristic of gels. Organosilicon compounds are hybrid molecules that have both inorganic and organic components and can enhance the properties and performance of HMAs.
  • 1.6K
  • 20 Sep 2023
Topic Review
Amazon Natural Fibers
The Amazon rainforest, spanning multiple countries in South America, is the world’s largest equatorial expanse, housing a vast array of relatively unknown plant and animal species. Encompassing the planet’s greatest flora, the Amazon offers a tremendous variety of plants from which natural lignocellulosic fibers (NLFs) can be extracted. In this century, NLFs, which have long been utilized by indigenous populations of the Amazon, have garnered interest as potential reinforcements for composites, whether polymer- or cement-based, in various technical applications such as packaging, construction, automotive products, and ballistic armor. A comparison with synthetic materials like glass, carbon, and aramid fibers, as well as other established NLFs, highlights the cost and specific property advantages of Amazon natural fibers (ANFs). 
  • 1.6K
  • 25 Jan 2024
Topic Review
Endocannabinoid System Present in the Glioblastoma Tumour Microenvironment
The highly aggressive and invasive glioblastoma (GBM) tumour is the most malignant lesion among adult-type diffuse gliomas, representing the most common primary brain tumour in the neuro-oncology practice of adults. With a poor overall prognosis and strong resistance to treatment, this nervous system tumour requires new, innovative treatment. GBM is a polymorphic tumour consisting of an array of stromal cells and various malignant cells contributing to tumour initiation, progression, and treatment response. Cannabinoids possess anti-cancer potencies against glioma cell lines and in animal models. To improve existing treatment, cannabinoids as functionalised ligands on nanocarriers were investigated as potential anti-cancer agents. The GBM tumour microenvironment is a multifaceted system consisting of resident or recruited immune cells, extracellular matrix components, tissue-resident cells, and soluble factors. 
  • 1.6K
  • 31 Jan 2024
Topic Review
Alzheimer's disease
Alzheimer's disease (AD) is a multifactorial disease and the most common neurodegenerative disorder affecting the elderly population world-wide.The used medications treat the symptoms of AD, but without any delay on the progression of the disease. Curcumin presented favorable effects on AD. In the last decade curcumin analogues and derivatives have been synthesized in an attempt to optimize the beneficial properties of curcumin and improve its absorbance and  distribution per os as a therapeutic agent. Reviewing the bibliographical data of the last decade, information on the structures and / or chemical groups that are associated with specific action against AD, was gathered, derived from docking studies, (Q)SAR from vitro and in vivo tests. Phenolic hydroxyl groups might contribute to the anti-amyloidogenic activity. Phenyl methoxy groups seems to contribute to the suppression of Aβ42 and to the suppression of APP. Hydrophobic interactions revealed to be important. The presence of flexible moieties at the linker are crucial for the inhibition of Aβ aggregation. The inhibitory activity of derivatives is increased with the expansion of the aromatic rings. The keto-enol tautomer form offers as a new modification for the design of amyloid-binding agents. Taking the above under consideration  innovative design  and synthesis will lead to more potent and specific curcumin analogues and derivatives against AD.
  • 1.6K
  • 30 Oct 2020
Topic Review
Capillary-Driven Flow Device
The capillary flow device works on the principle of capillary-driven flow microfluidics and allows detection by multiple microchannels in a single microchip via smartphone imaging/portable detectors. Compared to other types of devices such as dipsticks and paper microfluidic devices, this device is fabricated with cheaper materials, coated with minute amounts of reagents and offers multiplexity on a single microchip. The sample is loaded into the microchannels via capillary force, which eliminates the requirement of external/internal fluidic mechanisms or controls. A capillary-driven flow device was developed in this study which is simple to operate and allows loading multiple samples in a single device.
  • 1.6K
  • 30 Oct 2020
Topic Review
Dengue and Chikungunya
Dengue and chikungunya are the vector-borne diseases, that are transmitted to humans by the mosquitoes Aedes aegypti and Aedes albopictus. This study aimed to show the spatial and temporal distribution of those diseases in the Hindu Kush Himalayan region.   
  • 1.6K
  • 27 Oct 2020
Topic Review
Chitin- and Chitosan-Based Derivatives
This review deals with the utilization of chitin and chitosan derivatives in agriculture. In particular it summarizes recent results concerning the utilization of these compounds to face biotic and abiotic stresses. In addition the review summarizes recent results about the utilization of chitin- and chitosan-based materials for the recovery of waste water and soil contaminaded by different chemicals
  • 1.6K
  • 27 Oct 2020
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