Single Plastic Research Articles

‘Tabs versus Jabs’ time and motion study involving experiential learning student pharmacists: how long to prepare intravenous versus oral antibiotics?

Abstract Introduction Approximately one-third of inpatients in Scotland are prescribed antibiotics1. Patients prescribed IV antibiotics should be reviewed regularly and switched to oral therapy when clinically appropriate. Optimising IV to oral switch (IVOST) is often perceived as challenging2 and risks associated with IV access and patient comfort benefits to IVOST are well known. Workforce time required to administer IV medicines compared to oral equivalents is rarely considered in the risk-benefit assessment to IVOST2. To quantify this difference, a medicines administration time and motion study was undertaken. Aim To conduct a time and motion study to explore antibiotic administration in NHS Lanarkshire (NHSL) district general hospitals: University Hospitals Hairmyres, Wishaw, and Monklands. Objectives To measure time taken by nursing staff to prepare and administer IV/oral antibiotics. To explore potential nursing time saved if IVOST. To make recommendations to NHSL’s Antimicrobial Management Committee on inpatient antibiotic use. To involve final year Student Pharmacists in a multidisciplinary (MDT) project during placement. Methods Data were collected by Student Pharmacists on Antimicrobial/Surgical Experiential Learning (EL) placements as a novel approach to specialist EL. Data were collected during midday medication rounds in a surgical ward at each hospital. Nurses were observed administering antibiotics and the time taken recorded included medicine preparation; patient identification; assessment of peripheral venous catheter; and gathering IV equipment. The timer stopped when medication was administered to the patient. IV infusion duration was not included. Data were recorded in an Excel spreadsheet in HH:MM:SS. This study did not require review by an NHS Research Ethics Committee under the updated Governance Arrangements for Research Ethics Committees (GAfREC) 2020 Edition; although local permission was sought from service leads. Results Mean nursing time to prepare IV antibiotic administration was 11 minutes 55 seconds (n=20). Mean nursing time for oral administration was 1 minute 59 seconds (n=10). Nursing staff take 6 times longer to prepare IV compared to oral antibiotics for patient administration. Potential nursing time saved per individual IVOST is approximately 10 minutes. Discussion/Conclusion Results suggest IVOST would reduce nursing time involved in medicines administration, with IVOST for one patient taking antibiotics three times daily potentially saving 30 minutes of nursing time alone. Some antibiotics have excellent oral bioavailability and this project highlights the need to educate clinical teams on selecting oral route for high bioavailability antibiotics when safe and clinically appropriate. Student pharmacists observed that nurses managed multiple interruptions and spent time looking for IV equipment, commenting that IV antibiotics produced more waste (single use plastics, syringes, packaging). Student pharmacists had a better understanding of medicines administration and nursing roles following involvement in the study. Limitations Small sample size, time constraints, data did not include infusion durations or administrations outside drug rounds. Benefits of IVOST are well known and the results of this study are comparable to similar studies in the UK. NHSL’s Antimicrobial Team are disseminating key information from this study in line with local and national guidelines. Student Pharmacists effectively contributed to a novel EL placement project and this improved their understanding of nursing roles within the MDT.

The effect of single pigtail bile duct stents without lateral wings bile duct drainage after removal of common bile duct stones in endoscopic retrograde cholangiopancreatography

Objective: To analyze the effect of single pigtail bile duct stents without lateral wings bile duct drainage after removal of common bile duct stones in endoscopic retrograde cholangiopancreatography (ERCP). Methods: Patients who underwent ERCP and implantation of a single pigtail bile duct stent for choledocholithiasis in Cholelithic Center of East Hospital Affiliated to Tongji University from January 2019 to September 2023 were retrospectively selected and divided into lateral wingless group (without the lateral wing) and lateral wing group(with the lateral wing) according to whether the lateral wings of the single pigtail bile plastic stents were preserved. The patients were followed up for 1 to 3 months. The stent detachment rate at 2 days, 1 week and 1 month, as well as the incidence of postoperative complications at 1 week and 1 month after ERCP were compared between the two groups. Results: A total of 402 patients were included, including 177 males and 225 females, aged 32-83 (58±12) years. There were 215 cases in the lateral wingless group and 187 cases in the lateral wing group. The stent detachment rate in the lateral wingless group was higher than that in the lateral wing group at 2 days after ERCP [12.6% (27/215) vs 5.9% (11/187), P=0.022]. The stent detachment rate in the lateral wingless was higher than that in the lateral wing group at 1 week after ERCP [87.0% (187/215) vs 25.1% (47/187), P<0.001]. The stent detachment rate in the lateral wing group was higher than that in the lateral wing group at 1 month after ERCP [97.2% (206/215) vs 67.3% (126/187), P<0.001]. The incidence of postoperative complications at 1 week after ERCP revealed no statistical significance between the two groups[(10.7% (23/215) vs 8.6% (16/187), P>0.05]. The incidence of postoperative complications at 1 month after ERCP in the lateral wingless group was lower than that in the lateral wing group [0.9% (2/215) vs 9.6% (18/187), P=0.001]. Conclusion: After the removal of choledocholithiasis with ERCP, bile is drained by a single pigtail bile duct stent with lateral removal, which has a high rate of natural shedding and a low incidence of complications.

Development and validation of hydrophobic molded pulp nursery pots made of hemp hurd

Biodegradable nursery pots (BNPs) composed of 50 % hemp hurd and 50 % recycled cardboard fibers (w/w dry basis) were produced using a custom-built handheld molded pulp device. Milling followed by sequential peracetic acid and sodium hydroxide delignification treatment reduced lignin content of hemp hurd from 23.76 % to 2.39 %, liberating cellulose and hemicellulose fibers for enabling the formation of interfiber interactions in molded pulp formulations. Beeswax and precipitated calcium carbonate based hydrophobic coating at ~10 μm thickness significantly enhanced hydrophobicity of the BNPs, as indicated by the surface contact and sliding angle of 116.25° and 34.82°, respectively. Anaerobic biodegradability of BNP was confirmed via carbon dioxide and methane gas accumulation measurements. Developed BNPs were successfully validated through an eleven week greenhouse planting trial. This study introduced a new biodegradable molded pulp formulation made from hemp hurd and validated its application as an alternative to single use plastic nursery pots for growing seedlings.

Identifying the distribution and source of riverine plastic waste contamination: case study of Brantas River in Malang city

Brantas River experiences significant pollution due to domestic and industrial wastes. This condition also causes natural disasters such as floods. Single use plastics generally made up a large portion of local wastes. However, previous studies mostly investigated plastic waste pollution and local waste management habits as separate topics. Therefore, the objects of this study are the plastic wastes in Brantas River, as microplastic particles, and the identification of its source. The assessments were based on microplastic counts, macroinvertebrate bioassessment with SIGNAL-2 index, and the quantitative data of local domestic waste management at three Stations in Malang City area. Riverine microplastic pollutant concentrations and its sources were both successfully identified and solved. The results showed that the highest riverine microplastic particles were found in Station 3. This station only had four macroinvertebrate taxa with a SIGNAL-2 score of 4.42, indicating severe degradation. Quantitative data showed that 80 % of Station 3 residents threw plastic wastes directly to Brantas River. The low macroinvertebrate counts possibly caused by ingestion of microplastic from households and small-scale enterprises which heavily utilized single use plastics to trade their goods. The first distinctive feature of this study is the comparability of the microplastic, and macroinvertebrate counts with the river degradation status. Secondly, the quantitative data can serve as complementary evidence. Practically, the obtained results can be developed into an integrated plastic waste management plan for the residents surrounding the rivers, particularly in developing countries with similar socio-cultural conditions as elaborated in this study, to maintain the ecosystem quality

Eco-Sustainability in Hospital Pharmacy: A Pilot Survey on 'Going Green'.

Purpose: Between 2009 and 2015, the Canadian health care system was estimated to be responsible for 4.6% of national carbon emissions. Determine awareness of and describe eco-initiatives that the department of pharmacy can implement to aim to reduce the carbon footprint in hospital pharmacy in an effort to 'go green'. Methods: In a quality improvement initiative, pharmacy employees (i.e. pharmacists and pharmacy technicians) completed a cross-sectional survey designed to gauge willingness to 'go green' at work, to identify actionable areas of waste, and to assess commuting practices. Results: A total of 15 respondents completed the survey conducted March 14th -April 7th, 2022. Most respondents (73%) were willing to engage in more sustainable practices at work. The main barriers to implementing green practices at work were 'too time consuming' (20%), 'adds too much complexity' (20%), and 'cost' (16%). For commuting, 60% indicated the primary mode of transportation as 'personal vehicle', where 'subsidized transit' and was listed as the greatest incentive that could encourage a greener commute. The three largest areas of waste cited were 'single use plastic' (36%), 'limited of awareness of green practices' (15%), and 'lights left on in empty rooms' (12%). Conclusions: Pharmacy staff shared willingness to engage in more sustainable 'go green' practices but raised challenges to do so. With the knowledge that Canada has the second most climate intensive health system, there is a need for future research to describe how hospital pharmacies can contribute strategically to 'go green', advancing with implementing low carbon sustainable pharmacy practices.

Multimodal Pilot Evaluation of a Hyaluronic Acid Infraorbital Filler Using Precise, Multi-Positional, 3D Imaging Quantification, Patient Reported Outcomes, and Anatomic Cadaveric Assessments

Abstract Background Despite the high demand of filler in the infraorbital area, there remains debate on injection practices, precise anatomical placement, and hyaluronic acid (HA) filler behavior. Objectives We aimed to contribute to the clinical and anatomic understanding of infraorbital HA injection via a prospective patient injection study in combination with a cadaveric analysis. Methods Patients were injected with Volbella XC into the tear trough region by a single experienced aesthetic plastic surgeon. Over a 90-day period, precise undereye volumetric measurements using 3D photogrammetry (VECTRA-M3) and patient reported outcomes (FACE-Q) were collected and analyzed relative to two pretreatment severity scales. Juvéderm Vycross and Restylane NASHA products were injected into the infraorbital and malar region in six cephalus specimens and evaluated with regards to the anatomic injection location with and without common clinical physical manipulations. Results Eleven patients participated with a 100% retention rate. Infraorbital HA volume maintenance was 70-81% at 30 days and 50-70% at 90 days. Significant improvement was noted in the eyes, overall facial appearance, and cheekbones (p&amp;lt;0.05) with FACE-Q outcomes, irrespective of pretreatment severity. In the cadaver examination, we observed differences in the anatomic locations occupied by Juvéderm and Restylane products as well as in behavior after physical manipulation between gel types. Conclusions Volbella XC effectively augments undereye volume to diminish infraorbital hollowing as measured over a 90-day period with significantly improved PROs. Enhanced knowledge of the behavior of Volbella XC and other HA fillers in this sensitive anatomic region will lead to improved patient outcomes.

Reusable glassware for routine cell culture—a sterile, sustainable and affordable alternative to single-use plastics

Cell culture is a cornerstone of in vitro biological research. Whilst glassware was once commonplace in tissue culture facilities, in recent decades laboratories have moved towards a heavy reliance on single use plastics for routine procedures. Single use plastics allow for accessible, sterile, and often affordable equipment that comes at a high environmental cost. We developed a glassware preparation and cleaning process that allowed the comparison of “traditional” plastic-heavy, and adapted “sustainable,” cell culture practices, to empirically compare the sterility, viability, and proliferative capacity of cells cultured with differing techniques, by observing IL-6 production, morphology, and proliferation rate of cultured human pulmonary fibroblast cells. During which, we calculated the carbon footprint of traditional versus sustainable methods. We additionally endeavored to provide a realistic overview of the steps required to transition to more sustainable cell culture practices and make suggestions to ease the cost, labor, and time required to uptake similar practices in other laboratories. Cells cultured using reusable glassware did not show signs of contamination or stress compared to cells grown solely with plasticware, and glassware baked at 180°C for 120 min was sufficiently decontaminated and depyrogenated for culturing these cells. An individual researcher adopting the same methodology could reduce their carbon footprint by 105.92 kg of Carbon dioxide equivalent (CO2e) whilst also saving money (£408.78) over a 10-year period. We predict that these benefits would be greater if more researchers were to uptake these adapted practices. We intend for this paper to reassure researchers that viable, sterile, and sustainable routine cell culture can be achieved with little upfront cost to the researcher, with the prospective benefit of greatly reducing the cost to the environment. We additionally hope that increased uptake, and thus demand of more sustainable practices, encourages suppliers, policy makers, and funding bodies to make sustainable practices more accessible to individual researchers and institutions worldwide.

Risk factors and a prediction model for pain recurrence after pancreatic stent removal in painful chronic pancreatitis.

Endoscopic pancreatic stenting (EPS) is an effective treatment modality for painful chronic pancreatitis. However, little is known about the factors that cause pain recurrence after stent removal, and there are no clear criteria for stent removal. We aimed to develop a prediction model for pain recurrence by identifying its risk factors. We retrospectively reviewed 95 patients who underwent EPS due to pain for the first time using a single plastic stent between January 2007 and July 2022 at our institute. Univariate and multivariate stepwise Cox proportional hazards models were used to identify the risk factors for pain recurrence, and a prediction model was developed based on the identified factors. Of the 95 enrolled patients, 89 (93.7%) achieved pain relief and 73 (76.8%) did stent removal. Of the 69 patients with a follow-up period ≥6 months after stent removal, 29 (42.0%) had pain recurrence during the median follow-up period of 59 months. Serum lipase level (p = 0.034) and pancreatic parenchymal thickness (p = 0.022) on computed tomography or magnetic resonance imaging were identified as independent risk factors for pain recurrence. The prediction model based on the identified factors had good discrimination ability, with a concordance index of 0.74, and could stratify pain recurrence rates. We identified the risk factors and developed a new prediction model for pain recurrence following stent removal. This model might be useful for decision-making in pancreatic stent management, such as deciding whether to remove a pancreatic stent, continue EPS, or convert to surgery.

Strategically shifting paradigms: the new era of DIEP flaps with minimally invasive mastectomy: a retrospective cross-sectional study

BackgroundThe free deep inferior epigastric artery perforator (DIEP) flap is the gold standard in autologous breast reconstruction. Asian patients often present with a smaller body mass index with relatively insufficient tissue. To restore appropriate symmetry, a larger flap inset ratio must be transferred. Supercharging of the second vein or inclusion of bilateral pedicle is commonly required. Current paradigm shifts in mastectomy has also resulted in more minimally invasive surgeries (MIS) espousing smaller lateral incisions, leading to a significant change in available recipient vessels. This study aimed to demonstrate our experience in changing strategies of DIEP flaps following the evolution of mastectomy techniques.MethodsBetween October 2008 and March 2022, retrospective data was gathered for 278 patients who underwent breast reconstruction surgery utilizing DIEP flaps by a single plastic surgeon. These patients were divided into two distinct groups based on their operation dates, with November 2018 marking a pivotal moment when the first MIS, including endoscopic-assisted and robot-assisted mastectomy, was introduced.ResultsA total of 278 patients were included. Bipedicle vessel utilization for flap supercharge saw a significant increase (15.9% vs. 7%, p < 0.001), while the use of the superior inferior epigastric vein (SIEV) decreased (5.1% vs. 17.1%, p = 0.01). Preceding MIS, SIEV was the primary choice for flap supercharge (96.0%, p < 0.001), whereas post-introduction, the contralateral DIEP pedicle gained prominence (75.9%, p < 0.001). There was also an increased utilization of thoracodorsal artery and lateral thoracic artery following MIS.ConclusionThese findings underscore the profound impact of MIS on the strategic choices made in DIEP flap-based breast reconstruction.Trial registrationThis study is retrospectively registered on ClinicalTrials.gov (NCT06321549).

Appraisal of awareness about single use plastic bags (supbs) among consumers and shopkeepers of Lanka market, Varanasi, Uttar Pradesh, India

Abstract The awareness level of humans varies depending upon various known and unknown factors. Environmental awareness of an individual is the reflection of his/her thoughts, feelings and sensitivities towards the environment and its associated problems like degradation. It is the most important parameter for the measurement of implementation of government’s policies designed for the safeguard of environment and other related issues. The Indian Government decision for the complete ban on the Single-Use Plastic Bags (SUPBs) has been implemented in the whole country since 01 July 2022. Single-use plastic bags pose serious concerns for the environment and the economy of the country. The consumption as well as the disposal of plastic-related products is increasing day by day in India. Around 3.5 million tonnes of plastic waste are generated every year (CPCB 2020). The present paper is about the appraisal of the awareness level of consumers and shopkeepers about the use of plastic bags. In the present study, the primary survey is conducted to understand the awareness of consumers and shopkeepers regarding Single-Use Plastic Bags (SUPBs) in Lanka market, Varanasi, Uttar Pradesh. The study tries to relate the level of literacy, economic status, hesitation to carry own bags and demand for the plastic bags with the environment awareness level. Study reflects, there is a strong relationship between uses of plastic bags with economic, social, cultural, political status of the people. It also reflects the lack of enforcement of policies about the Single-Use Plastic Bags (SUPBs).

Controllable preparation of carbon nanofiber membranes for enhanced flexibility and permeability

The electrospinning-produced carbon nanofiber membranes (CNFM) have been applied in many fields for their three-dimensional porous networks, however, the natural fragility impedes their practical applications. Introducing plasticizers into carbon fibers has been proven an efficient way to increase the flexibility of CNFM but the extent is limited. This work explored dual plasticizers strategy to improve the flexibility of CNFM. The addition of zinc acetate and tetraethyl orthosilicate leads to bigger carbon nanofibers and higher mean pore diameters. They can be transformed into SiO2 and ZnO nanoparticles that embed in the carbon fibers, and act as plasticizers to inhibit stress diffusion. The Young's modulus of the optimal SZCNFM-2.0-1.5-700 is 31.0 MPa, which is lower than single plasticizer can reduce. The mechanism of dual plasticizers collaboratively improving the flexibility of SZCNFM was proved based on the characterization results. The SZCNFM-2.0-1.5-700 with well flexibility also revealed high permeability, for instance, the gravity-induced cyclohexane flux is 486.67 L m−2 h−1. Furthermore, the SZCNFM-2.0-1.5-700 requires only half the time compared to the commercial filter membrane when separating the same amount of Pd@CN suspension in the suction filter.

Extent of Compliance of Ordinance Prohibiting the Use of Styrofoam Containers and Regulating the Use of Single Use Plastics in Cabugao Public Market

Extent of Compliance of Ordinance Prohibiting the Use of Styrofoam Containers and Regulating the Use of Single Use Plastics in Cabugao Public Market

Assessing the Effectiveness of the Plastic Ban in the City of Bangalore in Addressing the Market Failure Associated with It

The Bruhat Bengaluru Mahanagara Palike Solid Waste Management (BBMP-SWM) Bye-laws, 2019 was passed by the BBMP in 2019 to ensure proper waste management in the city alongside new rules on the consumption of plastic. According to the Karnataka state plastic board, every citizen, on an average, consumes 16kgs of plastic every month. The extended essay aims towards answering the question “To what extent has the Bruhat Bengaluru Mahanagara Palike Solid Waste Management (BBMP-SWM) Bye-laws, 2019 helped in reducing the negative externalities caused by the overconsumption of single-use plastic.” This study will be examining the effects of this law on the production and consumption of single-use plastics. Through this policy, the BBMP aims to revise the 2016 Karnataka State plastic Ban and enforce it in a stricter manner. This topic is significant as an estimated 20% of the 4000-tonne waste produced by the city consists of plastic. Plastics are not biodegradable, which increases pollution. Through this ban, the Bruhat Bengaluru Mahanagara Palike aims to reduce the external cost caused by reducing plastic consumption. Even if the plastic is marked as “recyclable” over 90% of the plastic is never actually recycled. India has been generating over 3.5 million tonnes of plastic every year. In 2017, plastic resulted in over 2.3 million premature deaths in India because of this, India made it onto the top 10 list along with China and The United States. Hence, the topic is of significant investigation. Over the years, there have been a lot of plastic bans implemented by the government. The most recent one is the Central plastic ban of 2021. Single use plastic does not biodegrade, it breaks down into smaller microplastics which continue polluting the environment.

Application of single surface isotropic damage plasticity model in nonlinear dynamic analysis of the Koyna Dam

PurposeIn the present study, the application of a recent damage plasticity model is presented for nonlinear dynamic analysis of the Koyna gravity dam. This is a single surface isotropic damage plasticity concrete model, which is based on the decomposition of stresses and was proposed in a previous study. The theoretical aspects of the model are initially reviewed, and a few preliminary verification examples are illustrated. Thereafter, the HHT-α (i.e. Hilber–Hughes–Taylor) algorithm is presented for nonlinear dynamic analysis of concrete gravity dams.Design/methodology/approachBased on the prepared tools, nonlinear behavior of the Koyna Dam is studied by applying the invoked damage plasticity model. For this purpose, three cases are considered for the present study. Case A, which is based on the linear model, is mainly used for comparative purposes. The other two cases (B and C) correspond to the nonlinear (i.e. damage plasticity) model. The basic data for these two cases are similar. However, the employed damping algorithms are different and correspond to constant and variable damping algorithms, respectively. This means that the damping matrix is either kept constant or updated for all iterations of different time increments through the course of analysis.FindingsThe time histories of horizontal displacement at the dam crest were initially compared for the three cases: the linear Case A, and two nonlinear Cases B and C. It was observed that nonlinear cases’ responses begin to deviate from the corresponding linear case after the time of about 4.3 s. However, the amount of change for Case C (i.e. variable damping) was much greater than for Case B (i.e. constant damping). This was manifested initially in the peaks of response. It was also noticed that the period of response changed slightly for Case B in comparison with the linear Case A, while this change was significant for Case C. The obtained tensile and compressive damages were subsequently compared for the two nonlinear cases. For constant damping Case B, it was noticed that tensile damage occurred in the D/S face kink and on the U/S face slightly at a lower elevation. Moreover, it had a scattered nature. However, in variable damping Case C, it was noticed that tensile damage was much more localized and acted similar to a discrete crack. Of course, both cases also show tensile damages at the dam’s heel. In regard to compressive damages, it is observed that low values are occurring for both nonlinear cases as expected.Originality/valueThe application of a recent single surface isotropic damage plasticity concrete model is presented for nonlinear dynamic analysis of the Koyna gravity dam. The nonlinear response of the dam is investigated for two different damping algorithms. Moreover, the influence of variable characteristic length is also investigated in the latter part of this study.

The impact of self-directed learning on reducing single use plastic in back-of-house restaurant operations

ABSTRACT The purpose of the study was to determine the barriers to single-use plastic (SUP) reduction, specifically in the back-of-house (BOH) of restaurants, based on preexisting attitudes and perceived barriers. The associated psychological barriers were reflected upon in the context of adult learning theory and self-directed learning, as a novel setting in which to apply these theories. This study assessed the barriers to SUP reduction in restaurants by conducting fourteen qualitative interviews with small- to medium-sized restaurant operators in Canada which were digitally transcribed verbatim and analyzed using thematic content analysis. The study found that the most common barriers to reducing SUPs in the BOH are: cost, lack of time, and suppliers. The study also finds that there is a disconnect between the participants’ attitudes toward SUPs and their perceived barriers, and that there is a lack of access to resources for learning as a barrier. This study adds to self-directed learnings theory’s influence and limitations on sustainability behaviors and the application of self-directed learning to a unique setting. It also concludes that the restaurant BOH environment is akin to a self-directed learning environment. This study has implications for restaurant owners and operators attempting to reduce their SUP consumption.

Biodegradation of Plastic Wastes in Soil: A Review on Testing and Evaluation Procedures

The recalcitrant behaviour of plastic creates an acute pollution on soil and aquatic biota. The plastic polymer synthesised from petroleum takes several hundred years to degrade. During excavation activities on the lands within or at the outskirts of urban limits, single use plastic wrappers and bags that were buried long ago, can be found in large quantities. Researchers have already identified the potentiality of microorganisms to biodegrade the plastic polymers. These microorganisms utilise plastic as a sole source of carbon and mineralise them into carbon dioxide under optimum environmental conditions. This paper provides a brief review on the biodegradation studies carried out by various researchers, spectra of microorganisms identified with the potential to degrade various polymeric substances, methods of testing and evaluations in order to quantify the effectiveness of degradation, their shortfalls and risks involved in implementing bioremediation technique in the field. A review on other related aspects that are deemed to be relevant to this topic are also discussed.

Breaking the plastic mould: rethinking single use plastics at medical school

Breaking the plastic mould: rethinking single use plastics at medical school

Enhancing sustainable waste management: Hydrothermal carbonization of polyethylene terephthalate and polystyrene plastics for energy recovery

Hydrothermal carbonization (HTC) of single plastic polymers such as polyethylene terephthalate (PET) and polystyrene (PS) has not yet been explored on a large scale, particularly their thermal behavior, chemical transformations under subcritical conditions, and the energy properties of the resultant hydrochar. This study investigated these aspects by employing techniques, such as thermogravimetric analysis (TGA), Fourier transformed infrared spectroscopy (FTIR), elemental and calorific analysis. The results show that PET hydrochar has a superior energy densification (1.37) and energy yield (89 %) compared to PS hydrochar (1.13, 54 %). Hydrothermal carbonization modifies the chemical structure of the polymers by increasing the number of carbonyl groups (CO) in PET and forming new ones in PS, and by enhancing hydroxyl groups (OH) in PET while retaining them in PS. Both materials preserve their aromatic and aliphatic structures, with the introduction of alkenes groups (CC) in the PET hydrochar. PET hydrochar begins to decompose at lower temperatures (150–270 °C) than PS hydrochar (242–283 °C) but reaches higher peak temperatures (420–585 °C vs. 390–470 °C), with both types achieving similar burnout temperatures (650–800 °C). PET hydrochar recorded a higher activation energy (121–126 kJ/mol) than PS hydrochar (67–74 kJ/mol) with the Mampel first-order reaction model as the best fit.

Synapse-type-specific competitive Hebbian learning forms functional recurrent networks

Cortical networks exhibit complex stimulus-response patterns that are based on specific recurrent interactions between neurons. For example, the balance between excitatory and inhibitory currents has been identified as a central component of cortical computations. However, it remains unclear how the required synaptic connectivity can emerge in developing circuits where synapses between excitatory and inhibitory neurons are simultaneously plastic. Using theory and modeling, we propose that a wide range of cortical response properties can arise from a single plasticity paradigm that acts simultaneously at all excitatory and inhibitory connections-Hebbian learning that is stabilized by the synapse-type-specific competition for a limited supply of synaptic resources. In plastic recurrent circuits, this competition enables the formation and decorrelation of inhibition-balanced receptive fields. Networks develop an assembly structure with stronger synaptic connections between similarly tuned excitatory and inhibitory neurons and exhibit response normalization and orientation-specific center-surround suppression, reflecting the stimulus statistics during training. These results demonstrate how neurons can self-organize into functional networks and suggest an essential role for synapse-type-specific competitive learning in the development of cortical circuits.

Solid Waste Generation and Management Practices at Sherubtse College

The enduring challenge of waste management poses a significant and ongoing global concern, demanding urgent and concerted efforts for sustainable solutions. Waste-related issues, ranging from inadequate disposal to the overwhelming volume of single use plastics, have consistently plagued communities worldwide. In light of these challenges, this study seeks to contribute valuable insights toward the development of effective strategies on both local and global fronts. The study sampled student hostels and staff quarters to understand the waste generation and management practices at Sherubtse College. Dry wastes were collected over a period of 9 weeks. Through the segregation and quantification carried out weekly, it is known that, about 0.07 kilogram(kg) of dry waste was generated by each student and 0.34 kg per staff household in a day. Among the dry waste collected, papers weighed the most. A survey was also conducted on wet waste generated on campus. It was found that per day about 0.64 kg of wet waste was generated by each staff household and 1.41 kg per hostel. In our quest to minimize waste, the analysis of quantified waste serves as a foundational starting point, providing a crucial understanding of production patterns and guiding targeted efforts toward effective waste reduction.