Optimal Level Research Articles

The Evolution of the U.S. Military Presence in Europe (2017–2023)

The article examines the evolution of the U.S. military presence in Europe as the whole and in key NATO member states between 2017 and 2023. The author employs the theory of armed forces development. The paper compares the size of the U.S. military presence in Europe at the end of the Cold War with that during the contemporary confrontation with Russia. By the mid-2020s, the size of the U.S. military presence, nearing 100 thousand troops can be considered close to its upper limit. The optimal level, taking into account capabilities and objectives, was estimated at 80 thousand troops. The dynamics of U.S. Army brigades’ deployments in Europe are explored. The article also traces the evolution of U.S. contingents in Italy and Germany, where military units were no longer predominant, having been largely replaced by various support forces, and their role as sources for reinforcing the U.S. forces in Eastern Europe. Also, the forms of U.S. military presence in Northern Norway are discussed. The author explores the U.S. approach to the rotational deployment of the Armored Brigade Combat Team (ABCT) in Poland (since 2017) and the Infantry Brigade Combat Team (IBCT) in Romania (since 2022), along with the establishment of division and corps headquarters in both countries. The noticeable increase in U.S. military presence in Europe between February and June 2022 set the framework for the New NATO Force Model (NNFM), approved at Madrid summit, and underscored the significant contributions made by European member states.

INNOVATIVE BLENDS OF GGBFS, METAKAOLIN, AND ALCCOFINE FOR ENHANCED MECHANICAL PROPERTIES IN GREEN CONCRETE

This research aims to improve the sustainability and mechanical properties of concrete by using partial replacement of cement with Ground Granulated Blast Furnace Slag (GGBFS), Alccofine (AL), and Metakaolin (MK). The study compares the effects of different proportions of GGBFS (0-50%), Alccofine (0-20%), and Metakaolin (0-15%) on the compressive, tensile, and flexural strength and at curing ages of 7th, 28th, 56th, and 90th days. The effective proportions of the replacements were determined to be 30% GGBFS, 15 % Alccofine, and 10% Metakaolin in ratios, which considerably improved the structural characteristics of conventional concrete. A ternary blend of these optimal levels was subsequently studied to determine its synergistic effect on the mechanical properties and microstructure. The ternary blend of these optimal levels demonstrated a 67.1% increase in compressive strength at 28 days and a 51.2% increase at 90 days compared to the control mix. Scanning Electron Microscopy (SEM) analysis suggested that increased pozzolanic activities, an increase in densities of the microstructure, and packing densities of the particles were the key factors for the improved performance. The results highlight that through the application of supplemental cementitious materials (SCMs), there exist promising opportunities in attaining high performance at the same time as a low environmental footprint that could help in concrete innovation for more sustainable solutions.

Analysis of engineering performance of concrete comprising recycled crushed plastic waste and fly ash

This study investigated the attributes of blending of recycled crushed polypropylene plastic coarse aggregates (PPCA) and fly ash (FA) towards the fresh and hardened properties of concrete. Natural coarse aggregate was partially replaced with PPCA at volumetric replacement levels up to 30% and cement was replaced with FA up to 20%. Initially, the performance of PPCA and FA in concrete was investigated distinctly. The incorporation of 30% of PPCA in concrete rather impaired the workability (from 95 mm – 50 mm: 47%) and the compressive strength (from 44.6 MPa to 31.4 MPa: 29.7%). By appropriate using of a superplasticizer, the loss in the workability could be recovered. Microstructural investigation was conducted employing scanning electron microscope analysis; it showed that the formation of a weak interfacial transition zone between PPCA and cement paste to be the reason for strength reduction in PPCA concrete. In contrast, the addition of 10 – 20% of FA in concrete improved the workability by 63.2% – 100%, but yet again, the 28-day compressive strength reduced by 15.8 – 35.6%. Meanwhile, thermal conductivity results and constitutive relationships proved that the use of PPCA enhanced the thermal insulation property and ductility of PPCA concrete, respectively. Eventually, a total of six concrete batches with binary blended PPCA and FA were cast to find the optimum replacement levels. The optimum binary combination with reasonable strength and workability at a minimal cost was achieved to be 10% PPCA and 20% FA.

Methylthio Substituent in SAM Constructing Regulatory Bridge with Photovoltaic Perovskites.

Inverted (p-i-n) perovskite solar cells (PSCs) have experienced remarkable advancements in recent years, which is largely attributed to the development of novel hole-transport layer (HTL) self-assembled monolayer (SAM) materials. Methoxy (MeO-) groups are typically introduced into SAM materials to enhance their wettability and effectively passivate the perovskite buried interface. However, MeO-based SAM materials exhibit a mismatch in highest occupied molecular orbital (HOMO) levels with perovskite layer due to the strong electron-donating capability of methoxy group. In this work, we introduced a methylthio (MeS-) substituent that is superior to methoxy as a highly versatile self-assembled molecular design strategy. As a soft base, sulfur atom forms a stronger Pb-S bond than oxygen. Additionally, within the CbzPh series of SAM materials, MeS-CbzPh demonstrates a more optimal HOMO level and enhanced hole transport properties. Consequently, the MeS-CbzPh HTL based device achieved an impressive power conversion efficiency (PCE) of 26.01 % and demonstrated high stability, retaining 93.3 % efficiency after 1000 hours of maximum power point tracking (MPPT). Moreover, in comparison with the commonly used 4PACz-based SAM molecular series, MeS-4PACz also exhibited the best performance among its peers. Our work provides valuable insights for the molecular design of SAM materials, offering a highly versatile functional substituent group.

Experimental design for testing Local Lorentz Invariance violation in gravity

Abstract Local Lorentz invariance is an important foundation of General Relativity, and
its high-precision testing can help to explore the unified theories. In this work, we focus on the local Lorentz violating effect in pure gravity with mass dimension $d$=6, and study the experimental design for testing local Lorentz violation with precision torsion pendulum experiments. By designing the striped test and source masses, and setting the appropriate azimuth angles of the experimental setup, we found the constraint accuracy of the local Lorentz violation coefficients is expected to be improved by one to two orders of magnitude compared with the international optimal level. Moreover, considering the difficulty level of changing the azimuth angle of the experimental setup in practical experiments, we proposed two experimental strategies and separately studied the azimuth-angle configurations corresponding to the optimal constraint of the local Lorentz violating coefficients, which can guide the development of the later experiments.

The Role of Dispositional Optimism in Psychological Well-Being and Social Anxiety Among University Students

Objectives: The primary goal of this study was to investigate the association between dispositional optimism psychological well-being and social anxiety in university students.Method: The correlational research design was used, and the sample was recruited employing the non-probability purposive sampling technique. The life Orientation Scale developed by Scheier et al., in 1994, the Psychological Well-being scale by Ryff & Keyes (1995), Social Anxiety Scale developed by Ejaz et al., (2020) along with the demographic sheet were utilized for the data collection. Results: The sample constituted 350 participants (165 males and 185 females), with ages ranging from 20-30 years (M=23.46, SD=3.22). Results revealed a significant association between dispositional optimism and all subscales of social anxiety and psychological well-being (p<.05). Similarly, significant differences among both genders were observed in levels of dispositional optimism, psychological well-being, and social anxiety (p<.01). Dispositional optimism and psychological wellbeing were also observed as the significant predictors of social anxiety in university students (p<.001). Likewise, the results proved that dispositional optimism was a significant moderator between psychological well-being and social anxiety (p<.01).Conclusion: the study concluded that dispositional optimism moderates the association between psychological well-being and a level of social anxiety.

The Biomechanics of Spinal Orthoses for Adolescent Idiopathic Scoliosis: A Systematic Review of the Controlling Forces

Background: Orthotic treatment is a well-acknowledged conservative treatment for moderate adolescent idiopathic scoliosis (AIS). The efficacy of this treatment is significantly determined by the forces applied to the bodies of patients. However, there is uncertainty regarding the optimal force levels that should be applied to the patient’s torso by spinal orthosis. This study aims to identify reference values for the controlling forces in AIS management. Methods: A comprehensive literature search was performed in five databases (PubMed, Scopus, Cochrane Library, CINAHL, and Web of Science). Only studies written in English and covering the force/pressure measurements of spinal orthosis for the treatment of AIS were included, without publication date restrictions. The methodological index for non-randomized studies (MINORS) was employed for the methodological quality assessment, and force measurements were standardized to pressure in kilopascals (kPa) for comparison. Results: From the initial 10,452 records, 10 studies were admitted for the final analysis. All the included studies reported the interface pressure between the thoracic (T) pad and patient’s trunk, and seven studies evaluated the pressure from the thoracolumbar/lumbar (TL/L) pad. These studies used different pressure sensors or transducers with the range from 5.6 to 82.5 kPa for the T pads, and 4.8 to 85.1 kPa for the TL/L pads. Four studies reported strap tensions of 26.8 to 60.4 N. Higher strap tension was correlated with increased interface pressure (r = 0.84). Conclusion: The mean strap tension was 42.5 N, the median interface pressure of the T pads was 8.75 kPa, and the median pressure of TL/L regions was 7.11 kPa without the outliers. The findings provide a baseline value for designing adjustable straps and strategically distributing pressure in orthoses.

Response of Microbiological Properties to Short-term Nitrogen Addition in Perennial Alpine Cultivated Grassland

Removing nitrogen limitation is necessary to increase plant productivity in alpine grasslands. A short-term nitrogen addition experiment was conducted to understand the effects of nitrogen addition on the soil physicochemical properties and microbial community structure of perennial alpine cultivated grassland in the region around Qinghai Lake. From June to August 2022, four N application gradients （T0： 0 kg·hm-2·a-1, T1： 22.5 kg·hm-2·a-1, T2： 45 kg·hm-2·a-1, T3： 67.5 kg·hm-2·a-1） were set up in a four-age perennial cultivated grassland, and soil samples were collected from the 0-20 cm soil layer. The soil physical and chemical properties and microbial community structure were determined under the different treatments. The results showed that soil water content （SWC）, soil organic carbon （SOC）, ammonium nitrogen （NH4+-N）, nitrate nitrogen （NO3--N）, available nitrogen （AN）, available phosphorus （AP）, total phosphorus （TP）, total nitrogen （TN）, and total carbon （TC） tended to increase with the increase in nitrogen application level and the T3 treatment significantly decreased the soil pH. Nitrogen addition did not significantly alter the Alpha diversity of soil microbial communities and different levels of nitrogen application affected the structure of soil microbial communities to different degrees. The T1 and T2 treatments increased the number of soil bacteria and fungi and T3 treatment decreased the number of soil bacteria and fungi. Nitrogen addition increased the relative abundance of the dominant flora of Actinobacteriota, Zygomycota, Blastococcus, and Gibberella and decreased the relative abundance of the dominant flora of Proteobacteria, Bacteroidota, Sphingomonas, and Claroideoglomus. RDA analysis showed that SOC and soil electrical conductivity （EC） were the key soil physicochemical factors affecting changes in soil bacterial communities, and soil pH was the main factor affecting the distribution of soil fungal communities. Collectively, 67.5 kg·hm-2·a-1 may be the optimal level of N application to improve the soil environment of perennial alpine cultivated grasslands.

Prediction and Optimization of Surface Roughness and Cutting Forces in Turning Process Using ANN, SHAP Analysis, and Hybrid MCDM Method

As manufacturing technologies advance, the integration of artificial neural networks in machining high-hardness materials and optimization of multi-objective parameters is becoming increasingly prevalent. By employing modeling and optimization strategies during the machining of such materials, manufacturers can improve surface roughness and tool life while minimizing cutting time, tool vibrations, and cutting forces. In this paper, the aim was to analyze the impact of input parameters (cutting speed, feed rate, depth of cut, and insert radius) on surface roughness and cutting forces during the machining of 90MnCrV7 using feed-forward neural network models and SHAP analysis. Afterward, multi-criteria optimization was applied to determine the optimal parameter levels to achieve minimum surface roughness and cutting forces using the modified PSI-TOPSIS method. According to the SHAP analysis, the insert radius has the most significant impact on the surface roughness and passive force, while in the multi-criteria analysis, according to ANOVA results, the insert radius has the most significant impact on all considered outputs. The results show that an insert radius of 0.8 mm, a cutting speed of 260 m/min, a feed rate of 0.08 mm, and a depth of cut of 0.5 mm are the optimal combination of input parameters.

Cortex kidney tissue partial oxygen pressure depends on percentage of active oxygenation during oxygenated hypothermic machine perfusion.

Preclinical and clinical studies have demonstrated the advantages of oxygenated hypothermic machine perfusion (HMPO2) during kidney preservation. However, the optimal oxygenation levels during HMPO2 remain undetermined. The aim of this study was to compare different levels of oxygenation (0%, 21%, 50%, and 100%) during 22 h of active oxygenated HMP (HMPO2) using oxygen preloading by bubbling oxygenation in the preservation solution and continuous surface oxygenation during MP in a porcine DCD model. After 60 min of warm ischemia time, both kidneys of an 80 kg pig were procured and randomized to one of the following groups: (1) 22-h static cold storage (n = 6), (2) 22-h HMP without active oxygenation (n = 6), (3) 22-h HMPO2 21% O2 (n = 6), (4) 22-h HMPO2 50% O2 (n = 6), and (5) 22-h HMPO2 100% O2 (n = 6). The primary outcome measure was to compare the different oxygen levels among the different groups assessed by cortex kidney tissue oxygen partial pressures (tpO2). Continuous HMPO2 resulted in a significant modification of cortex kidney tpO2. In addition, tpO2 was dependent on the percentage of oxygenation. One hundred percent oxygen resulted in a significantly higher tpO2 compared to all other study groups. In line with that, ATP resynthesis was significantly higher in the HMPO2 100% group. This study demonstrates that continuous HMPO2 results in a significant modification of tpO2 compared with SCS, and the degree of tpO2 is positively correlated with the percentage of active oxygenation during HMP. Metabolic profile analyses (ATP resynthesis) suggest that the aerobic mechanism is better supported with higher oxygen levels (50% and 100% oxygenation).

PENINGKATAN KENYAMANAN TERMAL TAMAN KOTA MELALUI MODEL TAMAN AIR BERARSITEKTUR TRADISONAL BALI

Thermal comfort is a crucial aspect in designing outdoor spaces such as urban parks. Traditional Balinese water gardens have the potential to enhance thermal comfort through the application of water elements and traditional architectural concepts. Previous research by Wirya et al. (2017) identified three models of traditional Balinese water gardens with optimal thermal comfort levels. However, the application of these models in modern urban parks has not been extensively studied. This research aims to develop an optimal urban park design concept in terms of thermal comfort by applying traditional Balinese water garden models. The method used is experimental, employing simulation techniques using Envi-met software. The research objects are three urban parks in Bali: Taman Kota Alit in Tabanan Regency, Lapangan Astina in Gianyar Regency, and Lapangan Kapten Mudita in Bangli Regency. The results show that the application of traditional Balinese water garden models can improve thermal comfort in urban parks. The distribution patterns of air temperature and humidity are more evenly spread with the presence of water elements and vegetation arranged according to traditional Balinese concepts. Wind speed is also better controlled, creating a more comfortable microclimate. The resulting design concept can serve as a recommendation for designing urban parks that are optimal in terms of thermal comfort while maintaining local architectural values.

Investigation of Microstructure and Mechanical Properties of Al Alloys Lap Joints by Friction Stir Welding

An experimental investigation on effect of friction stir lap welding (FSLW) process parameters on mechanical and microstructure of AA6082-O welds is presented. Three process parameters namely tool rotational speed (1000,1400 & 2000 rpm), tool shoulder diameter (18, 20 & 22 mm) and tool traverse speed (28, 56 & 80 mm/min) are considered. Experiments are planned as per L9 Taguchi array. Data are analyzed in terms of S/N ratio and Analysis of Variance (ANOVA). Tensile shear strength is observed in the range of 11.79 MPa to 29.23 MPa. It is observed that tool diameter and tool rotational speed are most significant factors affecting tensile shear strength. Optimum levels of process parameters (28 mm/min tool traverse speed, 18 mm tool diameter and 1400 rpm tool rotational speed) is decided based on analysis of experimental data. Using optimum process parameters for friction stir lap welding of Al alloys improved quality of welded joints can be made. Use of optimized parameters will improve the performance of the products in terms of durability and load carrying capacity.

Determination of the Optimal Level of the Span of a Management and its Influence on the Formation of the Organizational Structure

Determination of the Optimal Level of the Span of a Management and its Influence on the Formation of the Organizational Structure

Pathobiochemistry of Aging and Neurodegeneration: Deregulation of NAD+ Metabolism in Brain Cells

NAD+ plays a pivotal role in energy metabolism and adaptation to external stimuli and stressful conditions. A significant reduction in intracellular NAD+ levels is associated with aging and contributes to the development of chronic cardiovascular, neurodegenerative, and metabolic diseases. It is of particular importance to maintain optimal levels of NAD+ in cells with high energy consumption, particularly in the brain. Maintaining the tissue level of NAD+ with pharmacological tools has the potential to slow down the aging process, to prevent the development of age-related diseases. This review covers key aspects of NAD+ metabolism in terms of brain metabolic plasticity, including NAD+ biosynthesis and degradation in different types of brain cells, as well as its contribution to the development of neurodegeneration and aging, and highlights up-to-date approaches to modulate NAD+ levels in brain cells.

Use of Immunoglobulin Replacement Therapy in Clinical Practice: A Review

ABSTRACT Immunoglobulins (Igs) are produced by B lymphocytes and play a key role in humoral immunity. Igs are classified into five isotypes (IgG, IgA, IgM, IgE, and IgD). Their primary function is to recognize and bind to foreign antigens. When Igs bind to antigens, they facilitate phagocytosis and promote clearance mediated by other immune cells. It is an essential component in protecting the host from outside pathogens. Hypogammaglobulinemia predisposes an individual to severe and recurrent infections. Therefore, replacement therapy is recommended to maintain optimal Ig level. In addition, Igs can modulate immune responses by to neutralizing proteins such as endotoxins or receptor-binding antibodies. They can be used to manage excessive immune reactions and autoimmune-related diseases. In this review, we aimed to summarize the clinical indications for Ig therapy for practicing oncologists.

Optimization of high-throughput marker systems for genomic prediction in alfalfa family bulks.

Alfalfa (Medicago sativa L.) is a perennial forage legume esteemed for its exceptional quality and dry matter yield (DMY); however, alfalfa has historically exhibited low genetic gain for DMY. Advances in genotyping platforms paved the way for a cost-effective application of genomic prediction in alfalfa family bulks. In this context, the optimization of marker density holds potential to reallocate resources within genomic prediction pipelines. This study aimed to (i) test two genotyping platforms for population structure discrimination and predictive ability (PA) of genomic prediction models (G-BLUP) for DMY, and (ii) explore optimal levels of marker density to predict DMY in family bulks. For this, 160 nondormant alfalfa families were phenotyped for DMY across 11 harvests and genotyped via targeted sequencing using Capture-seq with 17K probes and the DArTag 3K panel. Both platforms discriminated similarly against the population structure and resulted in comparable PA for DMY. For genotyping optimization, different levels of marker density were randomly extracted from each platform. In both cases, a plateau was achieved around 500 markers, yielding similar PA as the full set of markers. For phenotyping optimization, models with 500 markers built with data from five harvests resulted in similar PA compared to the full set of 11 harvests and full set of markers. Altogether, genotyping and phenotyping efforts were optimized in terms of number of markers and harvests. Capture-seq and DArTag yielded similar results and have the flexibility to adjust their panels to meet breeders' needs in terms of marker density.

Hypertension awareness, treatment, control, and prognosis: insights from the sub-cohort of China PEACE million persons project.

It is unclear whether and to what extent hypertension (HTN) awareness, treatment, and control affect prognosis in real-world settings. This study utilized data from the sub-cohort of the China Patient-Centered Evaluative Assessment of Cardiac Events Million Persons Project. A total of 102,358 adults aged 35-75 years were enrolled from Guangdong Province between January 2016 and December 2020. The primary outcomes were hospitalizations for major adverse cardiovascular events (MACEs) (a composite of myocardial infarction, coronary heart disease, stroke, heart failure, and cardiovascular mortality) and all-cause mortality. The secondary outcomes were the individual components of MACEs. Among the HTN patients, the proportions of HTN awareness and treatment were 58.6% and 48.7%, respectively. Only 22.0% and 7.9% of the population had their blood pressure (BP) controlled at <140/90 and <130/80 mmHg. Older age, female sex, higher socioeconomic status, elevated body mass index and waist circumference, as well as a history of DM, dyslipidemia, and cardiovascular disease, were associated with increased HTN awareness, treatment, and control. Current smokers and drinkers experienced lower chances of HTN care cascade. Hypertensive individuals with BP controlled at <130/80 mmHg faced similar risks of MACEs and mortality compared to normotensive individuals, while hypertensive subjects with uncontrolled BP or unawareness of HTN exhibited nearly double the risk of adverse cardiovascular outcomes. In conclusion, several factors were significantly associated with the performance of HTN awareness, treatment, and control. Hypertensive individuals with BP controlled at an optimal level shared a similar risk for MACEs and mortality compared to their normotensive counterparts.

A randomized trial investigating the impact of response expectancy on the counting blessings intervention: the role of optimism as a moderator

IntroductionThis randomized controlled trial aimed to address a knowledge gap concerning the mechanisms responsible for the efficacy of gratitude interventions. Specifically, we investigated how various response expectancies (positive, ambiguous + negative, and no expectancy) impact the efficacy of the “counting blessings” intervention in influencing positive and negative emotions. Additionally, the study explores how optimism levels (high, medium, low) interact with these expectancies to influence intervention efficacy.MethodA total of 529 adult volunteers were recruited through social media and randomly assigned to one of three experimental conditions, Positive Condition (PC), Ambiguous + Negative Condition (ANC), No Expectancy Condition (NEC), using a Random Sequence Generator. Of these, 142 participants completed the seven-day counting blessings intervention, and 111 participated in a follow-up assessment 1 month later. Missing data were addressed using multiple imputation. The main outcomes were changes in positive and negative emotions, with moderation analysis assessing the interaction between optimism levels and response expectancies. The study adhered to the CONSORT guidelines.ResultsWhile no significant interaction was found between experimental conditions and time regarding emotional outcomes (p ˃ 0.05), moderation analysis revealed differential interactions between optimism levels and expectancies, particularly influencing positive emotions (p &amp;lt; 0.009). For participants with low optimism, positive emotions significantly increased from post-intervention to follow-up in the PC (t = −2.42, p &amp;lt; 0.016) and from pre-intervention to post-intervention in the ANC (t = 2.41, p &amp;lt; 0.018). Participants with medium optimism experienced an increase in positive emotions across all conditions from pre-intervention to follow-up and from post-intervention to follow-up (ps &amp;lt; 0.05). High optimism participants showed an increase in positive emotions from pre-intervention to follow-up and post-intervention to follow-up in the PC (t = 2.09, p &amp;lt; 0.038 and t = 3.06, p &amp;lt; 0.003) and NEC c (t = −2.76, p &amp;lt; 0.006 and t = 2.74, p &amp;lt; 0.007).ConclusionOur findings emphasize the effectiveness of a brief gratitude journal and underscore the nuanced role of response expectancy, especially in interaction with the initial level of optimism, in enhancing positive emotions. These results hold significance for both theoretical understanding and clinical applications.

White Grape Pomace Effect on Laying Hens’ Productivity, Egg Quality Traits, and Antioxidant Capacity Under Normal, Heat, and Cold Thermal Conditions

This study investigated the effect of white grape pomace (WGP) via a 6% level dietary supplementation on laying hens exposed to varying thermal stress conditions. The experiment was designed as a 2 × 3 factorial study, incorporating two dietary treatments (C and E) and three different thermal conditions: normal (NT: 22 °C), high stress (HST: 35 °C), and low stress (LST: 10 °C). Feed and water were provided ad libitum throughout the experiment. Results showed that the inclusion of 6% WGP in laying hens’ diet did not demonstrate beneficial effects under HST conditions, but under LST conditions, the WGP showed higher final body weight (1849.38 g) compared to both groups from the HST conditions (C 1599.40 g and WGP 1592.59 g), and the AEW (average egg weight) was highly significantly higher (p = 0.0001) compared to the C or NT groups (both groups, 2nd week), and the HST conditions (both groups, 2nd, 4th, and 6th weeks). HDEP (hen-day egg production) registered highly significant values (p = 0.0001) for the WGP group under HST conditions compared to HST conditions (both groups, 4th and 6th weeks). The whole egg weight was highly significant (p = 0.0001) for the WGP group under LTS conditions compared to the C group and to HST conditions (both groups, 2nd week and 6th week). The yolk weight parameter registered highly significant (p = 0.0001) values for the WGP group under LTS conditions compared to the C group and HST conditions (both groups, 2nd week; C group, 4th week; both groups 6th week) and the NT conditions (C group, 2nd week). Our study indicates that dietary supplementation with 6% white grape pomace (WGP) has potential benefits in LST conditions but limited efficacy under HST conditions. Further research is needed to explore the mechanisms and optimal inclusion levels of WGP in diets for laying hens exposed to different temperatures, especially in HST conditions.

Variation of Some Agro-Physiological and Biochemical Parameters of Wheat (Triticum aestivum L.) Varieties in Response to Nitrogen Fertilizer Rates at Djirataoua in Southern Niger Republic

Nitrogen is the most limiting plant nutrient element of soils in Niger. Farmers apply nitrogen to increase yield of cereal crops. A survey conducted at Djirataoua in southern Niger, revealed that wheat growers applied nitrogen fertilizer with less technical knowledge resulting in low response on growth and yield. To produce suitable recommendations to farmers, a field experiment was conducted during two dry seasons (2016/2017 and 2017/2018) at Djirataoua (13°25’59’’N, 7°8’12’’E). The aim of the study was to determine the optimum level of Nitrogen for highest yield and agro-physiological parameters of wheat varieties. Four Nitrogen levels (0, 100, 150 and 200 kg N ha-1) and four wheat varieties were evaluated in this study. The experiment was laid out in a split plot design with three replications. Data collected on grain yield, chlorophyll, Nitrogen uptake and protein content were subjected to the analysis of variance and mean comparison. The results showed that application of 150 kg N ha-1 Nitrogen resulted in highest grain yield (3202 kg ha-1), chlorophyll content (50.9 SPAD) N uptake (72.63 kg ha-1), and protein content (135.5 g kg-1). The wheat varieties were significantly different in these parameters. Reyna-28 and Sokoll/3/ produced higher grain yield and Nitrogen uptake. Higher protein content was observed in Norman and Sokoll/3/. Significant interactions were observed between Nitrogen rates and variety on yield characters, Nitrogen uptake and protein content. The highest grain yield, Nitrogen uptake and chlorophyll content were achieved by interaction of Reyna-28 and Sokoll/3/ with 150 kg N ha-1. Therefore, application of 150 kg N ha-1 and using varieties Reyna-28 or Sokoll/3/ is recommended to farmers for maximum grain yield and high protein content.